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7 


THE 

CAMBRIDGE   NATURAL   HISTORY 


EDITED    BY 


S.  F.  HARMER,  Sc.D.,  F.R.S.,  Fellow  of  King's  College,  Cambridge; 
Superintendent  of  the  University  Museum  of  Zoology 


AND 


A.    E.    SHIPLEY,    M.A.,    Fellow    of   Christ's    College,    Cambridge; 
University  Lecturer  on  the  Morphology  of  Invertebrates 


VOLUME  VI 


JUL  1  -  1P«1 


,9- 


INSECTS 


PART  II.  Hymenoptera  continued  (Tubulifera  and  Aculeata),  Coleoptera, 
Strepsiptera,  Lepidoptera,  Diptera,  Aphaniptera,  Thysanoptera, 
Hemiptera,  Anoplura. 


By  DAVID  SHARP,  M.A.  (Cantab.),  M.B.  (Edinb.),  F.R.S. 


MACMILLAN    AND    CO.,  LIMITED 

NEW  YORK:   THE    MACMILLAN    COMPANY 
I  9O  I 


All  rights  resen.<ed 


"Men  are  poor  things;   I  don't  know  why  the  world  thinks  so 
much  of  them." — Mrs.  Bee,  by  L.  &  M.  Wintle. 


First  Edition  1899 
Reprinted  1901 


CONTENTS 


PAGE 

SCHEME  OF  THE  CLASSIFICATION  ADOPTED  IN  THIS  BOOK  .      vii 


CHAPTER    I 

HYMENOPTERA  PETIOLATA  COXTINUED— SERIES  2.  TCBULIFERA  on  CHRYSI- 
DIDAE. — SERIES  3.  ACULEATA — GENERAL — CLASSIFICATION — DIVISION  I. 
ANTHOPHILA  OR  BEES  .  1 


CHAPTER    II 

HYMENOPTERA  ACULEATA  CONTINUED — DIVISION  II.  DIPLOPTERA  OR  WASPS 
— EUMENIDAE,  SOLITARY  TRUE  WASPS  —  VKSPIDAE,  SOCIAL  WASPS — 
MASARIDAE 


CHAPTER    III 

HYMENOPTERA  ACULEATA  CONTINUED  —  DIVISION  III.  FOSSORES  OR 
FOSSORIAL  SOLITARY  WASPS — FAMILY  SCOLIIDAE  OR  SUBTERRANEAN 
FOSSORES — FAMILY  POMPILIDAE  OR  R.UNNERS — FAMILY  SPHEGIDAE  OR 
PERFECT-STINGERS  90 


CHAPTER    IV 

HYMENOPTERA    ACULEATA    CONTINUED  —  DIVISION    IV.     FOKMICIDAE    OR 

ANTS  131 


CHAPTER    V 

COLEOPTERA  OR  BEETLES — STREPSIPTERA    .  ...   184 

CHAPTER    VI 
LEPIDOPTERA,  OR  BUTTERFLIES  AND  MOTHS  .  .     304 


VI  CONTENTS 


CHAPTEI!    VIT 

PAGE 

DIPTEKA,  on  FLIES — APHANIPTERA,  OR  FLEAS— THYSANOPTERA,  OR  THRIPS    438 


CHAPTER    VIII 

HEMIPTEUA,  OK  BUGS — ANOPLTJRA  .        .  .     532 


NOTES     .  •     602 

INDEX  *        °     603 


SCHEME  OF  THE  CLASSIFICATION  ADOPTED 
IN  THIS  BOOK 


Order. 


Sub-order,  Division, 
or  Series. 


Family. 


Sub-Family  or 
Tribe. 


Group. 


HYMENOPTERA  (  Petiolata. 

(continued from  -      (continued 
F).  (from  Vol.  V). 

Tubulifera  |  CHRYSIDIDAE  (p. 


Vol. 


HYMENOPTERA 

(continued) 


Aculeata 

(P-  4) 


AXTHOPHILA 

(p.  10) 
APIDAE  (p. 


FOSSORES  (p.  90) 

SCOLIIDAE 

(p.  94) 


-: 


IArcliiapides  (p.  21). 
Obtusilingues  (p.  22). 
Andrenides  (p.  23). 
•   Denudatae  (p.  29). 
10)      Scopulipedes  (p.  32). 
Dasygastres  (p.  35). 
s  Sociales  (p.  53). 

DlPLOPTERA 

(P-  71) 

(  EUMENIDAE  (p.  72). 
|  VESPIDAE  (p.  78). 
I  MASAIUDAE  (p.  88). 

Mutillides  (p.  94). 

Thynnides  (p.  96). 

Scoliides  (p.  97). 

Sapygides  (p.  99). 

Rhopalosomides  (p.  100). 
POMPILIDAE  (p.  101). 

'  Sphegides  (p.  107). 

Ampulicides  (p.  114). 

Larrides  (p.  116). 

Trypoxylonides  (p.  118). 
SPHEGIDAE         I  Astatides  (p.  119). 
(p.  107)         ]  Bembecides  (p.  119). 

Nyssonides  (p.  123). 

Philaiithides  (p.  124). 

Mimesides  (p.  127). 

Crabronides  (p.  128). 

'Camponotides  (p.  144). 
Dolichoderides  (p.  157). 

Myrmicini 

(p.  159). 
Attini  (p.  165). 

ilvrmicides  •   Pseud  oniyrmini 

(p.  158)  (p.  168)._ 

Cryptocerini 
"  (p.  169). 
Ponerides  (p.  170). 

I  Ecitonini 

Doiylides  (p.  174)]  D  J/^ 

(p.  177). 
Amblyoponides  (p.  180). 


HETEROGYXA 
(p.  131) 

FOBMICIDAE 

(p.  131) 


VI 11 


SCHEME  OF  CLASSIFICATION 


Order. 


Sub-Order,  Division 
or  Series. 


Sub-Family  or 
Tribe. 


COLEOPTERA 

(p.  184) 


Lamelli- 
cornia 

(p.  190) 


Adephaga  or 
Caraboidea 

(p.  200) 


Polymorpha 

(p.  213) 


I 
(Continued  on  the  nextp<i<f>. 


Family. 

'PASSALIDAE  (p.  192). 
LUCANIDAE  p.  193). 

j'Coprides  (p.  195). 
SC-ARABAEIIKVE  I  ^elolonthides  (p.  198). 


(p.  194) 


-  Rutelides  (p.  198). 

Dynastides  (p.  199). 
^  Cetoniidi 


Cetoniides  (p.  199). 

ClCINDELIPAE  (p.   201). 

fCarabides  (p.  206). 
CARABIDAE         |  Harpalides  (p.  206). 

(p.  204)        "I  Pseudomorphides  (p.  206). 
I.  Morraolycides  (p.  206). 

AMPHIZOIDAE  (p.  207). 

PKLOBUDAE  (p.    207). 

HALIPLIDAE  (p.  209). 
DYTISCIDAE  (p.  210). 

(  PAUSSIDAE  (p.  213). 
GYRINIDAK  (p.  215). 
HYDROPHILIDAK  (p.  216). 
PLATYPSYLLIDAE  (p.  219). 
LEPTINIDAE  (p.  220). 
SILPHIDAE  (p.  221). 

Sc'YDMAENIDAE  (p.    223). 
(iXn.STIDAE  (p.   223). 
PSKLAI'HIDAE  (p.   223). 

STAPHYLINIDAE  (p.  224). 
SPHAERIIDAE  (p.  227). 
TRICHOPTERYGIDAE  (p.  227). 
HYDROSCAI-HIDAE  (p.  228). 

CoRYLOPHIDAE  (p.   228). 
Sl'APHimiDAE  (p.   229). 

SYKTELIIDAE  (p.  229). 

HlSTERIDAE  (p.   230). 

PHALACKIHAE  (p.  231). 
NITIDULIDAE  (p.  231). 
TROGOSITIDAE  (p.  232). 

(Jnl.YDIIDAE  (p.   233). 
l!ll  YSODIDAE  (p.   234). 

CrcrjiDAE  (p.  234). 
CRYPTOPHAGIDAE  (p.  235). 
HELOTIDAE  (p.  235). 
THORICTIDAE  (p.  236). 

KlIiiTYLIDAE  (p.   236). 
M  YCF.TiiPHACIKAK  (p.   237). 
CiiCCIXELLIDAE  (p.   237). 
KXDOMYCHIPAE  (p.   239). 

MYCKTAKIHAK  (p.  239). 
l,\Ti:ii)iii>AK  (p.  240). 
AIUMERIDAK,  (p.  240). 
DKUMESTIDAK  (ji.  241). 
P,VI;KHIDAE  (p.  242). 
CYATHOCEUIDAE  (]i.  243). 

(  1  I  ui;\  ssl  DAK  i  p.    2  l:>). 
HETEUni'llUlliAK  'p.    213). 

I'AKMD  \i:    |>.  243  . 
LDERODONTJDAE  (p.  21 


SCHEME  OF  CLASSIFICATION 


IX 


Order. 


Sub  Order,  Division, 
or  Series. 


COLEOPTERA 

(continued) 


Polymorpha 

(continued] 


Heteromera 

(p.  262) 


Phytophaga 

(p.  276) 


Rhyncho- 
phora(p.  288) 


Strepsiptera 

(p.  298) 


Family. 


ClOIDAE  (p.  245). 

SPHINDIDAE  (p.  245). 

BOSTRICHIDAE  (p.   246). 


Sub- Family  or 
Tribe. 


Jf  Ptinides  (p.  246). 
Anobiides  (p.  246). 
(P-  248) 


Lampyrides  (p.  248). 
Telephorides  (p.  248). 


TINIDAE 

(p.  246) 

MALACODEK- 

MID4E 

»    948^ 

MELYRIDAE  (p.  252). 
CLERIDAE  (p.  253) 
LYMEXYLONIDAE  (p.  254). 
DASCILLIDAE  (p.  255). 
RHIPICERIDAE  (p.  256). 

'  '  Throscides  (p.  260). 

Eucnemides  (p.  260). 

Elaterides  (p.  260). 

Cebrionides  (p.  260). 

Perothopides  (p.  260). 
.  Cerophytides  (p.  260). 

.  BUPRESTIDAE  (p.   261). 


ELATERIDAE 
(p.  256). 


TEXEBRIOXIDAE  (p.  263). 
CISTELIDAE  (p.  264). 
LAGRIIDAE  (p."  264). 
OTHXIIDAE  (p.  265). 
AEGIALITIDAE  (p.  265). 

MONOMMIDAE  (p.    265). 

NILIOXIDAE  (p.  265). 
MELANDKYIDAE  (p.  265). 
PYTHIDAE  (p.  265). 
PYROCHROIDAE  (p.  266). 
AXTHICIDAE  (p.  266). 
OEDEMERIDAE  (p.  266). 

MORDELLIDAE  (p.   267). 

CAXTHARIDAE  (p.  269). 
TRICTEXOTOMIDAE  (p.  275). 

BRUCHIDAE  (p.  276) 


(  Eupoda  (p.  280). 
| 


CHRYSOMEL-       |  Camptosomes  (p.  281). 
IDAE  (p.  278)1  Cyclica  (p.  282). 

Cryptostomes  (p.  282). 


CERAMBYCIDAE  f  . 

-  Cerambycides  (p. 


-  . 

(  Lamiides  (p.  287). 


/'  ANTHRIBIPAE  (p.  290). 

|   CURCULIONIDAE  (p.  290). 
SCOLYTIDAE  (p.   294). 

BRENTHIDAE  (p.  295). 
f  AGLYCYDERIDAE  (p.  297). 
\  PROTERHINIDAE  (p.  298). 


STYLOPIDAE  (p.  298). 


SCHEME  OF  CLASSIFICATION 


Order. 


LEPIDOPTERA 

(p.  304) 


lib-Order,  Division,               FT  mil  \-                    Sub-Family  or 

or  Series.                                                                Tribe.' 

r 

[  Danaides  (p.  344). 

Ithomiides  (p.  346). 

Satyrides  (p.  347). 

XYMPHALIDAE  ,   Morphides  (p.  348). 

(p.  343)          "   Brassclides  (p.  349). 

Acraeides  (p.  350). 

Rhopalocera 

Heliconiides  (p.  351. 

(p.  341)       " 

v  Xyinphalides  (p.  352). 

ERYCIXIDAE        f  Eryciiiides  (p.  355). 

(p.  354)          \  Libytheides  (p.  355). 

LYCAEXIDAE  (p.  356). 

PIERIDAE  (p.  357). 

PAPILIOXIUAE  (p.  359). 

^HESPERIIDAE  (p.  363. 

CASTXIIDAE  (p.  371). 

XEOCASTXIIDAE  (p.  372). 

SATURXIIDAE  (p.  372). 

BRAHMAEIDAE  (p.  374). 

CERATOCAMPIDAE  (p.  375), 

BOMBYCIDAE  (p.  375). 

EUPTEROTIDAE  (p.  376). 

PEUOPHORIDAE  (p.  377^. 

SPHIXGIDAE  (p.  380). 

CUCYTIIDAE  (p.  382). 

XOTODOXTIDAE  (p.  383). 

CYMATOPHORIDAE  (p.  386). 

SESIIDAE  (p.  386). 

TlXAEGERIIDAE  (p.  387). 

SYXTOMIDAE  (p.  388,. 

ZYGAEXIDAE  (p.  390). 

< 

HlMAXTOPTERIDAE  (p.   392). 

HETEROGYXIDAE  (p.  392). 

PSYCHIDAE  (p.  392). 

COSSIDAE  (p.  395). 

ARBELIDAE  (p.  396). 

CHRYSOPOLOMIDAE  (p.  396). 

Heterocera 

(p.  366) 

HEPIALIDAE  (p.  396). 
CALLIDULIDAE  (p.  400). 
DREPAXIDAE  (p.  400). 

LlMACODIDAE  (p.   401). 

MEGALOPYGIDAE  (p.  404). 

THYRIDIDAE  (p.  404). 

LASIOCAMPIDAE  (p.  405). 

EXDIMIMIDAE  (p.  406). 

PTEROTHYSAXIDAE  (p.  406). 

LYMAXTRIIDAE  (p.  406). 

HYP.SIDAE  (p.  408). 

ARCTIIDAE  (p.  408). 

AHARISTIDAE  (p.  410). 

GEOMETRIDAE  (p.  411). 

XoCTl'IDAE  (p.   414). 

EPICOPEIIDAE  (p.  418). 

UUAXIIDAE  (p.  419). 

Kl'iri.KMIHAE  (p.    420). 

PYRALIDAE  (p.  420). 

I'l  1   Hi'l'lliiKIIiAE  (p.    426). 

A  1,1  ii  i  in  \i;    p.    126). 

TORTRICIDAK  (p.    427). 

TIXKIDAE  (p.  428). 

I 

EllIOCEPHALIDAE  (p.   'I:;.'!   . 

I 

.  MlCRdl'TERYGIDAE  (p.    K!.~> 

SCHEME  OF  CLASSIFICATION 


XI 


Order. 


Sub-Order,  Division, 
or  Series. 


Family. 


DIPTERA 

(p.  438) 


Sub-Family  or 
Tribe. 


Orthorrha- 
pha  Nemo- 
cera 

(p.  455) 


Orthorrha- 
pha  Bra 

chycera 
(pp.  455, 

478) 


Cyclorrha- 
pha  As- 
chiza 

(pp.  455, 

494) 


Cyclorrha- 
pha  Schi- 
zophora 

(pp.  456, 
503) 


I 


'  CECIDOMYIIDAE  (p.  458). 
MYCETOPHILIDAE  (p.  462). 
BLEPHAROCERIDAK  (p.  464). 
CULICIDAE.  (p.  466). 
CHIRONOMIDAE  (p.  468). 
ORPHXEPHILIDAE  (p.  470). 
PSYOHODIDAE  (p.  470). 
DIXIDAE  (p.  471). 

TiPULiDAF          (  ptych°I'terinae  (P-  4"2)- 
T^jS          \  Limnohiinae  (p.  473). 

(  Tipulinae  (p.  475). 

BlBIONIDAE  (p.   475). 
SlMULlIDAK  (p.    477). 

(p.  478). 


STRATIOMYIDAE  (p.  478). 
LEPTIDAE  (p.  479). 
TABANIDAE  (p.  481). 
ACANTHOMERIDAE  (p.  483). 
THEREYIDAE  (p.  484). 
SCEXOPIXIDAE  (p.  484). 
NEMESTRINIDAE  (p.  484). 

BOMBYLIIDAE  (p.  485). 
ACROCERIDAE  (p.  489). 
LOXCHOPTERIDAE  (p.  490). 

MYDAIDAE  (p.  491). 
ASILIDAE  (p.  491). 
APIOCERIDAE  (p.  492). 
EMPIDAE  (p.  492). 
_  DOLICHOPIDAE  (p.  493). 

'  PHORIDAE  (p.  494). 

PLATYPEZIDAE  (p.  496). 
•   PIPUXCULIDAE  (p.  496). 

CONOPIDAE  (p.  497). 
I  SYRPHIDAE  (p.  498). 

MtTSCIDAE   ACALYPTRATAE  (p.    503). 
AXTHOMYIIDAE  (p.  5*06). 

TACHIXIDAE  (p.  507). 
DEXIIDAE  (p.  510). 
SARCOPHAGIDAE  (p.  510). 

MUSCIDAE  (p.   511). 

OESTRIDAE  (p.  514). 


Pupipara         ( 

(pp.  456,   - 
517) 


HIPPOP,OSCIDAE  (p.  518). 
BRAULIDAE  (p.  520). 


j  STKEBLIDAE  (p.  521). 
I  XYCTERIBIIDAE  (p. 


521). 


APHANIPTERA    |       PULICID,E  (  , 

d<l<.  456,  522)  \ 


THYSANO-  f  Terebrantia  (p.  531). 

PTERA  (p.  526)  \  Tubulifera  (p.  531). 


XII 


SCHEME    OF    CLASSIFICATION 


Order. 


Sub-Order. 


Series. 


HEMIPTERA 

(p.  532) 


Heteroptera 

(pp.  543, 
544) 


GYMNOCER- 

ATA        (p. 

544) 


Homoptera 

(Pp.  543, 


'  Anoplura 
(p.  599.) 


CRYPTOCER- 

ATA         (p. 

562) 


Family. 
f  PENTATOMIDAE  (p.  545). 

COREIDAE  (p.   546). 

BERYTIDAE  (p.  548). 
LYGAEIDAE  (p.  548). 
PYRRHOCORIDAE  (p.  549). 
TINGIDAE  (p.  549). 
ARADIDAE  (p.  550). 
HEBRIDAE  (p.  551). 
HYDROMETRIDAE  (p.  551). 
HENICOCEPHALIDAE  (p.  554). 
PHYMATIDAE  (p.  554). 
REDUVIIDAE  (p.  555). 
AEPOPHILIDAE  (p.  -559). 
CERATOCOMBIDAE  (p.  559). 
CIMICIDAE  (p.  559). 
ANTHOCORIDAE  (p.  560). 

POLYCTENIDAE  (p.   560). 

CAPSIDAE  (p.  561). 
',  SALDIDAE  (p.  562). 

(GALGULIDAE  (p.  562). 
NEPIDAE  (p.  563). 
NAUCORIDAE  (p.  565). 
BELOSTOMIDAE  (p.  565). 
NOTONECTIDAE  (p.  567). 
CORIXIDAE  (p.  567). 


ClCATMDAE  (p.   568). 
m  I    FULGOP.IUAE  (ll.    574). 

TRIMERA   (p.  |  MEMBKACIDA^(p.  5f6). 

CERCOPIDAE  (p.  577). 
I,  JASSIDAE  (p.  578). 


f  PSYLLIDAE  (i).  578). 

DlMEKA       (P-l   ApHIDAE(p:1581). 

[  ALEURODIDAE  (p.  591). 


PEDICULIDAE  (p.  599). 


CHAPTEE   I 


HYMENOPTERA    PETIOLATA    COXTIXL'ED 

SERIES    2.    TUBULIFERA    OH    CHRYSIDIDAE SERIES    3.    ACULEATA- 

GENERAL CLASSIFICATION DIVISION  I.   ANTHOPHILA  OR  BEES 

THE  First  Series — Parasitica — ;of  the  Sub-Order  Hymenoptera 
Petiolata  was  discussed  in  the  previous  volume.  We  now  pass 
to  the  Second  Series. 

Series  2.  Hymenoptera  Tubulifera. 

T/'ochanters  undivided;  the  hind-body  consisting  of  from  three 
t<>  Jive  visible  segments;  the  female  with  an  ovipositor, 
usually  retracted,  transversely  segmented,  enveloping  a  Jine, 
pointed  style.  The  larvae  usually  live  in  the  cells  of  other 
Hijinenoptera. 

The  Tubulifera  form  but  a  small  group  in  comparison  with 
Parasitica  and  Aculeata,  the  other  two  Series  of  the  Sub-Order. 
Though  of  parasitic  habits,  they  do  not  appear  to  be  closely  allied 
to  any  of  the  families  of  Hymenoptera  Parasitica,  though  M.  du 
Buysson  suggests  that  they  have  some  affinity  with  Proctotrypidae  ; 
their  morphology  and  classification  have  been,  however,  but  little 
discussed,  and  have  not  been  the  subject  of  any  profound  investi- 
gation. At  present  it  is  only  necessary  to  recognise  one  family, 
viz.  Chrysididae  or  Ruby-wasps.1  These  Insects  are  usually  of 
glowing,  metallic  colours,  with  a  very  hard,  coarsely-sculptured 
integument.  Their  antennae  are  abruptly  elbowed,  the  joints 
not  being  numerous,  usually  about  thirteen,  and  frequently  so 

1  Systematic  monograph,  Mocsary,  Budapest,  1889.     Account  of  the  European 
Chrysididae,  R.  da  Buysson  in  Andre,  Sjiec.  gen.  Hym.  vol.  vi.  1896. 

VOL.  VI  IE  B 


HV.MEXOPTERA 


CHAP. 


connected  that  it  is  not  easy  to  count  them.  The  abdomen  is, 
in  the  great  majority,  of  very  peculiar  construction,  and  allows 
the  Insect  to  curl  it  completely  under  the  anterior  parts,  so  as  to 
roll  up  into  a,  little  ball ;  the  dorsal  plates  are  very  strongly 
arched,  and  seen  from  beneath  form  a  free  edge,  while  the  ventral 
plates  are  of  less  hard  consistence,  and  are  connected  with  the 
dorsal  plates  at  some  distance  from  the  free  edge,  so  that  the 
abdomen  appears  concave  beneath.  In  the  anomalous  genus 

Cleptcs  the  abdomen 
is,  however,  similar 
in  form  to  that  of 
the  Aculeate  Hynien- 
optera,  and  has  four 
or  five  visible  seg- 
\  ments,  instead  of  the 
three  or  four  that 
are  all  that  can  be 
seen  in  the  normal 
Chrysididae.  The 

larvae  of  the  Euby- 
iiies  have  the  same 
number  of  segments 
as  other  Hymenoptera  Petiolata.  The  difference  in  this  re- 
sprct  of  the  perfect  Chrysididae  from  other  Petiolata  is  due 
to  a  greater  number  of  the  terminal  segments  being  indrawn 
so  as  to  form  the  tube,  or  telescope-like  structure  from  which 
the  series  obtains  its  name.  This  tube  is  shown  partially 
extruded  in  Fig.  1  ;  when  fully  thrust  out  it  is  seen  to  lie 
segmented,  and  three  or  four  segments  may  be  distinguished. 
The  ovipositor  proper  is  concealed  within  this  tube  ;  it  appears 
to  be  of  the  nature  of  an  imperfect  sting ;  there  being  a  very 
sharply  pointed  style,  and  a  pair  of  enveloping  sheaths  ;  the  style 
really  consists  of  a  trough-like  plate  and  two  tine  rods  or  spiculae. 
There  are  no  poison  glands,  except  in  t'leptes,  which  form  appears 
to  come  very  near  to  the  Aculeate  series.  Some  of  the  Cbrysi- 

didii i  occasions  use  the  ovipositor  as  a  sting,  though  it  is  only 

capaldc,  of  iiillid.ing  a  very  minute  and  almost  innocuous  wound. 
Although  none  of  the  Huby-flies  attain  a  large   size,  they   arc 
usually  very   conspicuous   on   account  of  their  gaudy  or   brilliant 
colours.      They  are  amongst  the  most  restless  and  rapid  of  Insects  ; 


FIG.  1. —  Clirysis  -iyiiita,  ?. 


England. 


CHRYSIDIDAE 


they  love  the  hot  sunshine,  and  are  difficult  of  capture.  Though 
not  anywhere  numerous  in  species,  they  are  found  in  most  parts 
of  the  world.  In  Britain  we  have  about  twenty  species.  They 
usually  frequent  old  wood  or  masonry,  in  which  the  nests  of 
Aculeate  Hymenoptera  exist,  or  fly  rapidly  to  and  fro  about  the 
banks  of  earth  where  bees  nest.  Dr.  Chapman  has  observed  the 
habits  of  some  of  our  British  species.1  He  noticed  Clirysis 
iijiiita  nying  about  the  cell  of  Odynerus  parietum,  a  solitary 
wasp  that  provisions  its  nest  with  caterpillars;  in  this  cell  the 
(. '//  i't/sis  deposited  an  egg,  and  in  less  than  an  hour  the  wasp  had 
sealed  the  cell.  Two  days  afterwards  this  was  opened  and  was 
found  to  contain  a  larva  of  Clirysis  a  quarter  of  an  inch  long,  as 
well  as  the  Lepidopterous  larvae  stored  up  by  the  wasp,  but  there 
was  no  trace  of  egg  or  young  of  the  wasp.  Six  days  after  the 
egg  was  laid  the  Chrysis  had  eaten  all  the  food  and  was  full- 
grown,  having  moulted  three  or  four  times.  Afterwards  it  formed 
a  cocoon  in  which  to  complete  its  metamorphosis.  It  is,  however, 
more  usual  for  the  species  of  Chrysis  to  live  on  the  larva  of  the 
wasp  and  not  on  the  food ;  indeed,  it  has  recently  been  positively 
stated  that  Chrysis  never  eats  the  food  in  the  wasp's  cell,  but 
there  is  no  ground  whatever  for  rejecting  the  evidence  of  so  care- 
ful an  observer  as  Dr.  Chapman.  According  to  M.  du  Buys- 
son  the  larva  of  Clirysis  will  not  eat  the  lepidopterous  larvae, 
but  will  die  in  their  midst  .if  the  Odynerus  larva  does  not  de- 
velop ;  but  this  observation  probably  relates  only  to  such  species 
as  habitually  live  on  Odynerus  itself.  The  mother-wasp  of 
Chrysis  bidentata  searches  for  a  cell  of  Odynerus  spinipes  that  has 
not  been  properly  closed,  and  that  contains  a  full-grown  larva  of 
that  wasp  enclosed  in  its  cocoon.  Having  succeeded  in  its  search 
the  Chrysis  deposits  several  eggs — from  six  to  ten  ;  for  some 
reason  that  is  not  apparent  all  but  one  of  these  eggs  fail  to  pro- 
duce young ;  in  two  or  three  days  this  one  hatches,  the  others 
shrivelling  up.  The  young  Chrysis  larva  seizes  with  its  mouth 
a  fold  of  the  skin  of  the  helpless  larva  of  the  Odynerus,  and 
sucks  it  without  inflicting  any  visible  wound.  In  about  eleven 
days  the  Clirysis  has  changed  its  skin  four  times,  has  consumed 
all  the  larva  and  is  full-fed  ;  it  spins  its  own  cocoon  inside  that 
of  its  victim,  and  remains  therein  till  the  following  spring, 
when  it  changes  to  a  pupa,  and  in  less  than  three  weeks  there- 

1  Enf.  Mag.  vi.  1869,  p.  153. 


HYMENOl'TERA  CHAP. 


after  emerges  a  perfect  Chrysis  of  the  most  brilliant  colour,  and 
if  it  be  a  female  indefatigable  in  activity.  It  is  remarkable 

O  V 

that  the  larva  of  Chrysis  is  so  much  like  that  of  Odynerus  that 
the  two  can  only  be  distinguished  externally  by  the  colour,  the 
Odynerus  being  yellow  and  the  (.'/trysts  white  ;  but  this  is  only 
one  of  the  many  cases  in  which  host  and  parasite  are  extremely 
similar  to  the  eye.  Chrysis  shanghaiensis  has  been  reared  from 
the  cocoons  of  a  Lepidopterous  Insect — Monema  flavescens,  family 
Limacodidae— and  it  has  been  presumed  that  it  eats  the  larva 
therein  contained.  All  other  Chrysids,  so  far  as  known,  live  at 
the  expense  of  Hymenoptera  (usually,  as  we  have  seen,  actually 
consuming  their  bodies),  and  it  is  not  impossible  that  C.  shamj- 
haiensis  really  lives  on  a  Hymenopterous  parasite  in  the  cocoon 
of  the  Lepidopteron. 

Parnopcs  car  tic  a  frequents  the  nests  of  Benibex  rostra ta,  a 
solitary  wasp  that  has  the  unusual  habit  of  bringing  from  time 
to  time  a  supply  of  food  to  its  young  larva ;  for  this  purpose  it 
has  to  open  the  nest  in  which  its  young  is  enclosed,  and  the 
Pa  mopes  takes  advantage  of  this  habit  by  entering  the  cell  and 
depositing  there  an  egg  which  produces  a  larva  that  devours  that 
of  the  L'emlex.  The  species  of  the  anomalous  genus  Cleptes  live, 
it  is  believed,  at  the  expense  of  Tenthredinidae,  and  in  all  prob- 
ability oviposit  in  their  cocoons  which  are  placed  in  the  earth. 

Series  3.  Hymenoptera  Aculeata. 

The  females  (whether  workers  or  true  females)  provided  with  a 
sting:  trochanters  usually  'undivided-  (monotrochous).  Usual/// 
the  antennae  of  the  males  with  thirteen,  of  the  females  with 
twelve,  joints  (exceptions  in  ants  numerous^. 

These  characters  only  define  this  series  in  a  very  unsatisfac- 
tory manner,  as  no  means  of  distinguishing  the  "sting"  from  the 
homologous  structures  found  in  Tubulifera,  and  in  the  Procto- 
trypid  division  of  Hymenoptera  Parasitica,  have  been  pointed 
out.  As  the  structure  of  the  trochanters  is  subject  to  numerous 
exceptions,  the  classification  at  present  existing  is  an  arbitrary 
one.  It  would  probably  be  more  satisfactory  to  separate  the 
Proctotrypidae  (or  a  considerable  part  thereof)  from  the  Para- 
sitica,  and  unite  them  with  the  Tubulifera  and  Aculeata  in 
a  <_;ival  scries,  characterised  by  the  fact  that  the  ovipositor  is 


ACULEATA 


withdrawn  into  the  body  in  a  direct  manner  so  as  to  be  entirely 
internal,  whereas  in  the  Parasitica  it  is  not  withdrawn  in  this 
manner,  but  remains  truly  an  external  organ,  though  in  numerous 
cases  concealed  by  a  process  of  torsion  of  the  terminal  seg- 
ments. If  this  were  done  it  might  be  found  possible  to  divide 
the  great  group  thus  formed  into  t\vo  divisions  characterised  by 
the  fact  that  the  ovipositor  in  one  retains  its  function,  the  egg 


FIG.  2. — Diagram  of  upper  sur- 
face of  Priocnemis  affi-iiis  9, 
Pompilidae.  o,  ocelli  ;  7J1, 
pronotuni  ;  Rz,  mesonotum  ; 
B3,  scutellum  of  mesonotnm  ; 
B4,  post-scutelluni  or  middle 
part  of  metanotum  ;  B5,  propo- 
deuni  or  median  segment  (see 
vol.  v.  p.  491)  ;  If',  combing 
hairs,  pecten,  of  front  loot :  C1, 
first  segment  of  abdomen,  here 
not  forming  a  pedicel  or  stalk  : 
Z)1, coxa;  JL>'2,  trochauter;  Lt3, 
femur  ;  />6,  calcaria  or  spurs 
of  bind  leg  :  1  to  15,  iierv- 
ures  of  wings,  viz.  1,  costal  ; 
2,  post -costal  ;  3,  median  ; 
4,  posterior  ;  5,  stigma  ; 
6,  marginal  ;  7,  upper 
basal  ;  8,  lower  basal  ;  9,  9, 
cubital  ;  10,  the  three  sub- 
marginal  ;  11,  first  recurrent  ; 
12,  second  recurrent;  }?,, 
anterior  of  hind,  wing;  1J, 
median  ;  15,  posterior  :  I  to 
XI,  the  cells,  viz.  I.  upper 
basal  ;  II,  lower  basal  ;  III, 
marginal  :  IV,  V.  VI,  first, 
second  and  third  sub-mar- 
ginal ;  VII,  first  discoidal  ; 
VIII,  third  discoidal  ;  IX, 
second  discoidal  ;  X,  first 
apical  ;  XI,  second  apical. 


passing  through  it  (Proctotrypidae  and  Tubulifera),  while  in  the 
other   the   organ   in   question   serves  as  a  weapon   of  offence  and 
defence,  and  does   not   act  as  a  true  ovipositor,  the  egg  escaping 
at  its  base.      It  would,  however,  be  premature  to  adopt  so  revolu- 
tionary a  course   until   the  comparative  anatomy  of  the   organs 
concerned  shall  have  received  a  much  greater  share  of  attention.1 
We  have  dealt  with  the  external  anatomy  of  Hymenoptera  in 
1  For  new  views  on  this  subject  see  note  on  p.  602. 


HYMENOPTERA 


CHAl'. 


Vol.  V. ;  so  that  here  it  is  only  necessary  to  give  a  diagram  to 
explain  the  terms  used  in  the  descriptions  of  the  families  and 
sub-families  of  Aculeata,  and  to  discuss  briefly  their  characteristic 
structures. 

The  Sting  of  the  bee  has  been  described  in  detail  by  Kraepelin. 
Sollmann,  Carlet l  and  others.  It  is  an  extremely  perfect  me- 
chanical arrangement.  The  sting  itself  —  independent  of  the 
sheaths  and  adjuncts — consists  of  three  elongate  pieces,  one  of 
them  a  gouge-like  director,  the  other  two  pointed  and  barbed 
needles  ;  the  director  is  provided  with  a  bead  for  each  of  the 
needles  to  run  on,  these  latter  having  a  corresponding  groove  ; 
the  entrance  to  the  groove  is  narrower  than  its  subsequent 
diameter,  so  that  the  needles  play  up  and  down  on  the  director 

with  facility,  but  cannot  be 
dragged  away  from  it;  each 
needle  is  provided  with  an 
arm  at  the  base  to  which 
are  attached  the  muscles  for 
its  movement.  This  simple 
manner  of  describing  the 
mechanical  arrangement  is, 
however,  incomplete,  inas- 
much as  it  includes  no 
account  of  the  means  by 
which  the  poison  is  conveyed. 
This  is  done  by  a  very  com- 
plex set  of  modifications  of 
all  the  parts;  firstly,  the 
director  is  enlarged  at  the 
anterior  part  to  form  a 

PIG.  3.-Stingofhee.     A,  One  of  the  needles    chamber,    through    which     the 
separated  ;  a,  the  barbed  point ;  6,  piston  ;    needles  play  ;   the    needles    are 

f  1  I'l  i  i  T?  '  I"  »"ii»  t.'  i'ij  fijfi          Oi'n  i\-\  r\-\~t  r\*F         -flii. 


a 


B 


arm. 


B,     Tr;uis\  cisc     section     of    tic  •  i 

sting:    dd,  the  two   needles;    e,   bead   for  each     Provided     With     a     pro- 

the     needles;    /,     director;     g,  jectillg     piece,    wllicll,     aS     the 

f  poison.      (After  Carlet.) 


channel  of  pois 


needle    moves,   plays    in    the 


chamber  of  the,  director,  and  forces  downwards  any  liquid  that 
may  be  therein  ;  the  poison-glands  open  into  the  chamber,  and 
the  project  ions  on  the  needles,  acting  after  the  manner  of  a  piston, 
carry  the  poison  before  them.  The  needles  are  so  arranged  on 

1  Ann.  Sd.  Nat.  (7}  ix.  1890,  p.  1. 


ACULEATA— STING LARVA 


the  director  that  they  enclose  between  themselves  and  it  a  space 
that  forms  the  channel  along  which  the  poison  flows,  as  it  is 
carried  forwards  by  the  movement  of  the  pistons  attached  to 
the  needles.  If  the  needles  be  thrust  into  an  object  quite  as 
far  as,  or  beyond,  the  point  of  the  director  much  poison  may  be 
introduced  into  a  wound,  as  the  barbs  are  provided  with  small 
orifices  placed  one  above  the  other,  while  if  this  be  not  the  case 
much  of  the  liquid  will  flow  on  the  outside  of  the  object. 

According  to  Carlet  the  poison  of  the  bee  is  formed  by  the 
mixture  of  the  secretions  of  two  glands,  one  of  which  is  acid  and 
the  other  alkaline ;  it  is  very  deadly  in  its  effects  on  other 
Insects.  We  shall  see,  however,  that  the  Fossorial  Hymenoptera, 
which  catch  and  sting  living  prey  for  their  young,  frequently 
do  not  kill  but  only  stupefy  it,  and  Carlet  states  that  in  this  group 
the  alkaline  gland  is  absent  or  atrophied,  so  that  the  poison  con- 
sists only  of  the  acid  ;  it  is  thus,  he  thinks,  deprived  of  its  lethal 
power.  Moreover,  in  the  Fossoria  the  needles  are  destitute  of  barbs, 
so  that  the  sting  does  not  remain  in  the  wound.  Bordas,  however, 
states  l  that  in  all  the  numerous  Hymenoptera  he  has  examined, 
both  acid  and  alkaline  glands  exist,  but  exhibit  considerable  differ- 
ences of  form  in  the  various  groups.  He  gives  no  explanation 
of  the  variety  of  effects  of  the  poison  of  different  Aculeata. 

The  larvae  (for  figure  of  larva  of  Bombus,  see  Vol.  V.  p.  488) 
are,  without  known  exception,  legless  grubs,  of  soft  consistence, 
living  entirely  under  cover,  being  protected  either  in  cells,  or, 
in  the  case  of  social  Hymenoptera,  in  the  abodes  of  the  parents. 
The  larvae  of  Ants  and  fossorial  Hymenoptera  have  the  anterior 
parts  of  the  body  long  and  narrow  and  abruptly  flexed,  so  that 
their  heads  hang  down  in  a  helpless  manner.  All  the  larvae  of 
Aculeates,  so  far  as  known,  are  remarkable  from  the  fact  that  the 
posterior  part  of  the  alimentary  canal  does  not  connect  with  the 
stomach  till  the  larval  instar  is  more  or  less  advanced ;  hence  the 
food  amongst  which  they  live  cannot  be  sullied  by  faecal  matter. 
The  pupa  is  invariably  soft,  and  assumes  gradually  the  colour 
of  the  perfect  Insect.  Almost  nothing  is  known  as  to  the 
intimate  details  of  the  metamorphosis,  and  very  little  as  to  the 
changes  of  external  form.  According  to  Packard  "a  period  inter- 
venes between  the  stadium  of  the  full-grown  larva  and  that  of 
the  pupa,  in  which  a  series  of  changes  he  speaks  of  as  semi-pupal 

1   C.  £.  Ac.  Paris,  cxviii.  1894,  p.  873. 


8  HYMENOPTERA 


CHAP. 


are  passed  through  ;  these,  however,  have  not  been  followed  out 
in  the  case  of  any  individual,  and  it  is  not  possible  to  form  any 
final  idea  about  them,  but  it  seems  probable  that  they  are  largely 
changes  of  external  shape,  in  conformity  with  the  great  changes 
going  on  in  the  internal  organs.  Owing  to  the  fragmentary 
nature  of  observations,  much  obscurity  and  difference  of  opinion 
have  existed  as  to  the  metamorphosis  of  Aculeate  Hynienoptera. 
Sir  S.  Saunders  gives  the  following  statement  as  to  the  larva  of 
a  wasp  of  the  genus  Psiliglossa,1  just  before  it  assumes  the  pupal 
form  :  "  The  respective  segments,  which  are  very  distinctly  indi- 
cated, may  be  defined  as  follows : — The  five  anterior,  including 
the  head,  are  compactly  welded  together,  and  incapable  of  separate 
action  in  the  pseudo-pupa  state ;  the  third,  fourth,  and  fifth 
bearing  a  spiracle  on  either  side.  The  thoracical  region  termi- 
nating here,  the  two  anterior  segments  are  assignable  to  the 
development  of  the  imago  head,  as  pointed  out  by  Katzeburg." 
This  inference  is  not,  however,  correct.  We  have  seen  that  in 
the  perfect  Insect  of  Petiolate  Hymenoptera  the  first  abdominal 
segment  is  fixed  to  the  thorax,  and  Saunders'  statement  is  in- 
teresting as  showing  that  this  assignment  of  parts  already  exists 
in  the  larva,  but  it  in  no  way  proves  that  the  head  of  the  imago 
is  formed  from  the  thorax  of  the  larva.  It  has  been  stated 
that  the  larvae  of  the  Aculeata  have  a  different  number  of  seg- 
ments according  to  the  sex,  but  this  also  is  incorrect.  The 
difference  that  exists  in  the  perfect  Insects  in  this  respect  is  due 
to  the  withdrawal  of  the  terminal  three  segments  to  the  interior 
in  the  female,  and  of  two  only  in  the  male.  The  larva  consists 
of  fourteen  segments,  and  we  find  this  number  distributed  in  the 
female  perfect  Insect  as  follows :  one  constitutes  the  head,  four 
segments  the  thorax  and  propodeum,  followed  by  six  external  seg- 
ments of  the  restricted  abdomen,  and  three  for  the  internal  structures 
of  the  abdomen.  This  agrees  with  Corel's  statement  that  in  the 
ants  the  sting  is  placed  in  a  chamber  formed  by  three  segments. 
The  development  of  the  sting  of  the  common  bee  has  been 
studied  by  Dewitz.2  It  takes  place  in  the  last  larval  stage. 
Although  nothing  of  the  organ  is  visible  externally  in  the  adult 
larva,  yet  if  such  a  larva  be  placed  in  spirit,  there  can  be  seen 
within  the  skin  certain  small  appendages  on  the  ventral  surface 
of  the  penultimate  and  antepenultimate  abdominal  segments 
Trans,  cut.  Sac.  London,  1873,  p.  408.  -  Zcitschr.  iviss.  Zool.  xxv.  1875,  p.  184. 


ACULEATAy — DEVELOPMENT 


( Fig.  4,  A)  placed  two  on  the  one,  four  on  the  other  ;   these  are  the 

rudiments   of    the    sting.      In    the    course    of    development    the 

terminal  three  segments  are  taken  into  the  body,  and  the  external 

pair  of  the  appendages   of  the  twelfth 

!«>dy    segment    (the    ninth    abdominal) 

become  the   sheaths   of  the  sting,  and 

the  middle   pair   become    the   director ; 

the  pair  of  appendages  on   the   eleventh 

segment    give    rise    to    the    needles    or 

spiculae.      The   sting -rudiments  at    an 

earlier  stage  (Fig.  4,  C)    are  masses   of 

hypodermis    connected  with    tracheae ; 

there    is    then    but    one    pair    on    the 

twelfth  segment,  and  this   pair  coalesce 

to  form  a  single   mass ;   the  rudiments  G 

of  the  pair  that  form  the   director  are   FlG.  4.— Development  of  sting  of 

differentiated      secondarily     from     the        the  bee :  A  and  C,  ventral ;  B, 

side  view.     A,  End  of  abdomen 

primary  pair  ot  these  masses  01  hypo- 
dermis.  A  good  deal  of  discussion 
has  taken  place  as  to  whether  the 
component  parts  of  the  sting— 
gonapophyses — are  to  be  considered  as 
modifications  of  abdominal  extremities 
(i.e.  abdominal  legs  such  as  exist  in 
Myriapods).  Heymons  is  of  opinion 
that  this  is  not  the  case,  but  that  the 
leg-rudiments  and  gonapophysal  rudi- 
ments are  quite  distinct.1  The  origin 
of  the  sting  of  Hymenoptera  (and  of  the  ovipositor  of  parasitic 
Hymenoptera)  is  very  similar  to  that  of  the  ovipositor  of  Locusta 
(Vol.  V.  p.  315  of  this  work),  but  there  is  much  difference  in  the 
history  of  the  development  of  the  rudiments. 

Dewitz  has  also  traced  the  development  of  the  thoracic 
appendages  in  Hymenoptera.2  Although  no  legs  are  visible  in 
the  adult  larva,  they  really  arise  very  early  in  the  larval  life  from 
masses  of  hypodermis,  and  grow  in  the  interior  of  the  body,  so 
that  when  the  larva  is  adult  the  legs  exist  in  a  segmented  though 
rudimentary  condition  in  the  interior  of  the  body.  Dewitz's 
study  of  the  wing-development  is  less  complete. 

i.  Jahrb.  xxiv.  1896,  p.  192.       -  Zeitscltr.  iciss.  Zool.  xxx.  1878,  p.  78. 


of  adult  larva :  a,  b,  c,  d,  the 
last  four  segments,  c  being  the 
eleventh  body  segment,  11  ; 
b  bearing  two  pairs,  and  c  one 
pair,  of  rudiments.  B,  Tip  of 
abdomen  of  adult  bee  :  9,  the 
ninth,  d,  the  tenth  body  seg- 
ment. C,  Rudiments  in  the 
early  condition  as  seen  within 
the  body  :  c,  first  pair  ;  b,  the 
second  pair  not  yet  divided  into 
two  pairs  ;  b",  c',  commence- 
ment of  external  growths  from  . 
the  internal  projections.  (After 
Dewitz.) 


I O  HYMENOPTERA  CHAP. 

Four  primary  divisions  of  Aculeates  are  generally  recognised, 
viz.  Anthophila  (Bees),  Diploptera  (Wasps),  Fossores  (Solitary 
Wasps),  Heterogyna  (Ants).  Though  apparently  they  are  natural, 
it  is  impossible  to  define  them  by  characters  that  are  without 
some  exceptions,  especially  in  the  case  of  the  males.  Ashmead 
has  recently  proposed  l  to  divide  the  Fossores  ;  thus  making  five 
divisions  as  follows  :— 

Body  with  more  or  less  of  the  hairs  on  it  plumose  1.   Anthophila. 

Hairs  of  body  not  plumose. 

Pronotum  not  reaching  hack  to  tegulae      .  2.   Entomophila 

[  =  Fossores  part] 
Pronotum  reaching  hack  to  tegulae. 

Petiole  (articulating    segment  of  abdomen)  simple   without   scales  or 

nodes. 
Front  wings  in  repose  with  a  fold  making  them  narrow 

3.  Diploptera. 

Front  wings  not  folded  4.  Fossores  [part]. 

Petiole  with  a  scale  or  node  (an  irregular  elevation  on  the  upper  side) 

5.  Heterogyna. 

We  shall  here  follow  the  usual  method  of  treating  all  the 
fossorial  wasps  as  forming  a  single  group,  uniting  Ashmend's 
Entomophila  and  Fossores,  as  we  think  their  separation  is  only 
valid  for  the  purposes  of  a  table  ;  the  Pompilidae  placed  by  the 
American  savant  in  Fossores  being  as  much  allied  to  Entomo- 
phila as  they  are  to  the  other  Fossores  with  which  Ashmead 
associates  them. 

Division  I.  Anthophila  or  Apidae — Bees. 

Some  of  the  hairs  of  the  body  'plumose  ;  parts  of  the  mouth  elon- 
gated, sometimes  to  a  great  extent,  so  as  to  form  a  protrusible 
apparatus,  usual  I;/  tubular  with  a  very  flexible  tip.  Basal 
joint  of  hind  foot  elongate.  No  wingless  adult  forms ;  in 
some  cases  societies  are  formed,  and  then  barren  females  called 
workers  exist  in,  gr<'<//  numbers,  and  carry  on  the  industrial 
operations  of  the  community.  Food  always  derived  from  the 
vegetable  kingdom,  or  from  other  Bees. 

There  are  about  150  genera  and  1500  species  of  bees  at 
present  known.  Some  call  the  division  Mellifera  instead  of 
Anthophila.  The  term  Apidae  is  used  by  some  authorities  to  de- 
note all  the  bees,  while  others  limit  this  term  to  one  of  the  families 

1  Proc.  ent.  Soc.   jr<is/i//iit/nn,  iii.  1896,  p.  334. 


ANTHOPHILA BEES 


I  I 


or  sub-divisions.  The  bees  are,  as  a  rule,  distinguished  from 
other  Hymenoptera  by  the  hairs,  by  the  great  development  of  the 
mouth  parts  to  form  a  proboscis  (usually,  but  not  correctly,  called 
tongue),  and  by  the  modification  of  the  hind-legs ;  but  these 
distinctive  characters  are  in  some  of  the  species  exhibited  in  so 
minor  a  degree  of  perfection  that  it  is  not  easy  to  recognise  these 
primitive  forms  as  Anthophila.  A  few  general  remarks  on  the 
three  points  mentioned  will  enable  the  student  to  better  appreciate 
the  importance  of  certain  points  we  shall  subsequently  deal  with. 
The  bees  are,  as  a  rule,  much  more  covered  with  hair  than 
any  other  of  the  Hymenoptera.  Saunders  l  states  that  he  has 
examined  the  structure  of  the. 
hairs  in  all  the  genera  of  British 
Aculeata,  and  that  in  none  but 
the  Anthophila  do  branched  and 
plumose  hairs  occur.  The  func- 
tion of  this  kind  of  hairs  is 
unknown;  Saunders  suggests1  that 
they  may  be  instrumental  in  the 
gathering  of  pollen,  but  they 
occur  in  the  parasitic  bees  as 
well  as  in  the  males,  neither  of 
which  gather  pollen.  The  variety 
of  the  positions  they  occupy  on 
the  body  seems  to  offer  but  little 
support  to  the  suggestion.  Not 
all  the  hairs  of  the  bee's  body 

are      r>lm  IOSP      some     are      simule     FIG.  5.— Hairs  of  Bees :  A,  simple  hair 

from   abdomen   of  Osmia;   B,  spiral 

as  shown  in  Fig.  5,  A,  and  this  is 
specially  the  case  with  the  hairs 
that  are  placed  at  the  edges  of 
the  dilated  plates  for  carrying 

pollen.  In  some  forms  there  is  an  extensive  system  of  simple 
hairs  all  over  the  body,  and  the  "  feathers "  are  distributed 
between  these ;  and  we  do  not  see  any  reason  for  assuming  that 
the  feathered  are  superior  to  the  simple  hairs  for  gathering  and 
carrying  pollen.  Some  bees,  e.g.  Prosopis,  Ceratina,  have  very 
little  hair  on  the  body,  but  nevertheless  some  plumose  hairs 
are  always  present  even  though  they  be  very  short. 

1   Trans,  cnt.  Soc.  1878,  p.  169. 


1 

f 

\ 

\ 

\ 

\ 

\ 

, 

\ 

\ 

o 

'/ 

\l 

v 

v 

V 

v> 

y 

\ 

/ 

C\ 

\ 

hair  from  abdomen  of  Jlegacfiile  ;  C, 
plumose  hair  from  thorax  of  Mega- 
chile  ;  D,  from  thorax  of  Andrena 
dorsata  ;  E,  from  thorax  of  Prosopis. 


I  2 


HYMENOPTERA 


CHAP. 


The  hind-legs  of  bees  are  very  largely  used  in  the  industrial 
occupations  of  these  indefatigable  creatures;  one  of  their  chief 
functions  in  the  female  being  to  act  as  receptacles  for  carrying 
pollen  to  the  nest  :  they  exhibit,  however,  considerable  diversity. 
The  parts  most  modified  are  the  tibia  and  the  first  joint  of  the 
hind-foot.  Pollen  is  carried  by  other  parts  of  the  body  in  many 
bees,  and  even  the  hind-leg  itself  is  used  in  different  ways  for  the 

purpose  :  sometimes  the  outer  face 
of  the  tibia  is  highly  polished  and 
its  margins  surrounded  by  hair,  in 
which  case  pollen  plates  are  said  to 
exist  (Fig.  6,  A)  ;  sometimes  the  first 
joint  of  the  tarsus  is  analogous  to 
the  tibia  both  in  structure  and 
function  ;  in  other  cases  the  hind- 
legs  are  thick  and  densely  covered 
with  hair  that  retains  the  pollen 
between  the  separate  hairs.  In  this 
case  the  pollen  is  carried  home  in  a 
dry  state,  while,  in  the  species  with 
pollen  plates,  the  pollen  is  made 
into  a  mass  of  a  clay-like  consist- 
ence.1 The  legs  also  assist  in  arrang- 
ing the  pollen  on  the  other  parts  of 
the  body.  The  males  do  not  carry 

Fir,.  6.—  A.  Worker  of  the  honey-bee    pollen     aml    though     their    hind-legS 
(Aixsmellijim),  with  pollen  plates    -  -,•£-, 

la.i.-n  ;  B,  basal  portions   of  a  are    also    highly    modified,    yet    the 
middle-leg  (trochanter  with  part  of  modifications    do    not    agree    with 

coxa  and  ot  femur)  with  plumose 

hairs  and  grains  of  pollen  ;  c,  one  those  of  the  female,  and  their   fiuic- 
hair  bearing  pollen-grams. 


ftre    in    ^    probability    sexu.,l. 

The  parasitic  bees  also  do  not  carry  pollen,  and  exhibit  another 
series  of  structures.  The  most  interesting  case  in  this  series  of 
modifications  is  that  found  in  the  genus  Apis,Vfhere  the  hind-leg 
of  male,  female,  and  worker  are  all  different  (Fig.  25);  the  limb 
in  the  worker  being  highly  modified  for  industrial  purposes. 
This  case  has  been  frequently  referred  to,  in  consequence  of  the 
difficulty  that  exists  in  connection  with  its  heredity,  for  the 

1  The  mode  of  wetting  the  pollen  is  nut  clear.  Woltl'  says  it  is  done  1))-  an  i-xn- 
dation  from  the  tibia;  11.  M  idler  by  ;idmi,\t  lire  of  nectar  from  tin.'  bee's  mouth. 
The,  latter  view  is  more  probably  correct. 


BEES PROBOSCIS  I  3 


structure  exists  in  neither  of  the  parents.  It  is,  in  fact,  a  case 
of  a  very  special  adaptation  appearing  in  the  majority  of  the 
individuals  of  each  generation,  though  nothing  of  the  sort  occurs 
in  either  parent. 

The  proboscis  of  the  bee  l  is  a  very  complex  organ,  and  in  its 
extremely  developed  forms  exhibits  a  complication  of  details  and 
a  delicacy  of  structure  that  elicit  the  admiration  of  all  who  study 
it.  In  the  lower  bees,  howrever,  especially  in  Prosopis,  it  exists 
in  a  comparatively  simple  form  (Fig.  9,  B,  C),  that  differs  but  little 
from  what  is  seen  in  some  Vespidae  or  Fossores.  The  upper  lip 
and  the  mandibles  do  not  take  any  part  in  the  formation  of  the 
bee's  proboscis,  which  is  consequently  entirely  made  up  from  the 
lower  lip  and  the  maxillae,  the  former  of  these  two  organs  ex- 
hibiting the  greatest  modifications.  The  proboscis  is  situate  on 
the  lower  part  of  the  head,  and  in  repose  is  not  visible  ;  a  portion, 
and  that  by  no  means  an  inconsiderable  one,  of  its  modifications 
being  for  the  purpose  of  its  withdrawal  and  protection  when  not 
in  use.  For  this  object  the  under  side  of  the  head  is  provided 
with  a  very  deep  groove,  in  which  the  whole  organ  is,  in  bees 
with  a  short  proboscis,  withdrawn  ;  in  the  Apidae  with  a  long  pro- 
boscis this  groove  also  exists,  and  the  basal  part  of  the  proboscis 
is  buried  in  it  during  repose,  while  the  other  parts  of  the  elon- 
gate organ  are  doubled  on  the  basal  part,  so  that  they  extend 
backwards  under  the  body,  and  the  front  end  or  tip  of  the  tongue 
is,  when  in  repose,  its  most  posterior  part. 

For  the  extrusion  of  the  proboscis  there  exists  a  special 
apparatus  that  comes  into  play  after  the  mandibles  are  unlocked 
and  the  labrum  lifted.  This  extensive  apparatus  cannot  be  satis- 
factorily illustrated  by  a  drawing,  as  the  parts  composing  it  are 
placed  in  different  planes  ;  but  it  may  lie  described  by  saying 
that  the  cardo,  or  basal  hinge  of  the  maxilla,  changes  from  an 
oblique  to  a  vertical  position,  and  thrusts  the  base  of  the  pro- 
boscis out  of  the  groove.  The  maxillae  form  the  outer  sheath  of  the 
proboscis,  the  lower  lip  its  medial  part  (see  Figs.  7  and  9 ) ;  the 
base  of  the  lower  lip  is  attached  to  the  submentum,  which  rises 
with  the  cardo  so  tha.t  labium  and  maxillae  are  lifted  together  : 
the  co-operation  of  these  two  parts  is  effected  by  an  angular  piece 
called  the  lorum,  in  which  the  base  of  the  submentum  rests  ;  the 

1  In  studying  the  proboscis  the  student  will  do  well  to  take  a  Bombus  as  an 
example  ;  its  anatomy  being  more  easily  deciphered  than  that  of  the  honey-bee. 


HYMEN  OPT  ERA 


CHAP. 


submentum  is  articulated  with  the  mentuui  iu  such  a  manner  that 
the  two  can  either  be  placed  in  planes  at  a  right  angle  to  one 
another,  or  can  be  brought  into  one  continuous  plane,  and  by  this 
change  of  plane  the  basal  part  of  the  tongue  can  also  be  thrust 
forwards.  There  is  considerable  variety  in  the  lengths  of  these 
parts  in  different  genera,  and  the  lorum  varies  in  shape  in  accord- 
ance with  the  length  of  the  subinentuin.  The  lorum  is  a 

o 

peculiar  piece,  and  its  mechanical  adaptations  are  very  remark- 
able ;  usually  the  base  of  the  submentum  rests  in  the  angle 
formed  by  the  junction  of  the  two  sides  of  the  lorum,  but  in  A'ylu- 
copa,  where  the  submentum  is  unusually  short,  this  part  reposes 


7. 


FIG.  7.— Side  view  of  basal  portions  of  proboscis  of  Bombiis.  a,  Epipharyugeal  sclerites  ; 
6,  arrow  indicating  the  position  of  the  entrance  to  pharynx,  which  is  concealed  by 
the  epipharynx,  c  ;  d,  hypopharyugeal  sclerites  ;  e,  vacant  space  between  the  scales 
of  the  maxillae  through  which  the  nectar  comes  :  /,  lobe  ;  /',  stipes  ;  </,  cardo  of 
maxilla  :  h,  encephalic  pillar  on  which  the  cardo  swings  ;  i,  angle  of  junction  of  lores 
and  submentum  lorum  ;  k,  mentum  ;  I,  base  of  labial  palp  ;  m,  maxillary  palp. 

in  a  groove  on  the  back  of  the  lorum,  this  latter  having  a  very 
broad  truncated  apex  instead  of  an  angular  one;  in  the  condition 
of  repose  the  apex  of  the  lorum  rests  in  a  notch  on  the  middle  of 
the  back  of  the  oral  groove,  and  in  some  of  the  forms  with  elon- 
gate submentum,  this  depression  is  transformed  into  a  deep  hole, 
or  even  a  sort  of  tunnel,  so  as  to  permit  the  complete  stowing 
away  of  the  base  of  the  tongue,  which  would  otherwise  be  pre- 
vented by  the  long  submentum;  another  function  of  the  lorum 
appears  to  be  that,  as  it  extends,  its  arms  have  an  outward  thrust, 
and  so  separate  the  maxillae  from  the  labium.  In  addition  to 
these  parts  then-  are  also  four  elongate,  slender  sclerites  that  are 
only  brought  into  view  on  dissection,  and  that  no  doubt  assist  in 
correlating  the  movements  of  the  parts  of  the  mouth  and  hypo- 


BEES PROBOSCIS  I  5 


pharynx  ;  one  pair  of  these  strap-like  pieces  extends  backwards 
from  the  two  sides  of  the  base  of  the  epipharynx ;  Huxley  called 
them  selerites  of  the  oesophagus ;  a  better  name  would  be 
epipharyngeal  selerites  (Fig.  7,  «.) :  the  other  pair  pass  from  the 
terminations  of  the  epipharyngeal  selerites,  along  the  front  face  of 
the  hypopharynx,  down  to  the  mentum,  their  lower  parts  being 
concealed  by  the  stipites  of  the  maxillae  ;  these  are  the  hypo- 
pharyngeal  selerites,  and  we  believe  it  will  prove  that  they  play 
a  highly  important  part  in  deglutition.  When  the  labrum  of  a 
bee  is  raised  and  the  proboscis  depressed,  the  epipharynx  is  seen 
hanging  like  a  curtain  from  the  roof  of  the  head  ;  this  structure 
plays  an  important  part  in  the  act  of  deglutition.  The  entrance 
to  the  pharynx,  or  commencement  of  the  alimentary  canal,  is 
placed  below  the  base  of  the  epipharynx.  As  we  are  not  aware 
of  any  good  delineations  of  the  basal  parts  of  the  proboscis  we 
give  a  figure  thereof  (Fig.  7).  The  maxillae  in  the  higher  bees 
are  extremely  modified  so  as  to  form  a  sheath,  and  their  palpi 
are  minute  ;  in  the  lower  bees  the  palpi  have  the  structure  usual 
in  mandibulate  Insects. 

Eeturning  to  the  consideration  of  the  lower  lip,  we  find  that 
there  is  attached  to  the  mentum  a  pair  of  elongate  organs  that 
extend  forwards  and  form  a  tube  or  sheath,  enclosed  by  the 
maxillary  sheath  we  have  previously  mentioned ;  these  are  the 
greatly  modified  labial  palpi,  their  distal  parts  still  retaining  the 
palpar  form  ;  and  in  the  lower  bees  the  labial  palpi  are,  like  the 
maxillary,  of  the  form  usual  in  mandibulate  Insects.  Between 
the  labial  palps  and  the  central  organ  of  the  lip  there  is  attached 
a  pair  of  delicate  organs,  the  paraglossae. 

There  remains  for  consideration  the  most  remarkable  part  of 
the  proboscis,  the  long,  delicate,  hairy  organ  which  the  bee 
thrusts  out  from  the  tip  of  the  shining  tube  formed  by  the  labial 
palps  and  the  maxillae,  described  above,  and  which  looks  like 
a  prolongation  of  the  mentum.  This  organ  is  variously  called 
ligula,  lingua,  or  tongue.1  We  prefer  the  first  of  these  names. 

According  to  Breithaupt  and  Cheshire  the  structure  of  the 
ligula  is  highly  remarkable  ;  it  is  a  tube  (filled  with  fluid  from 
the  body  cavity),  and  with  a  groove  underneath  caused  by  a  large 
part  of  the  circumference  of  the  tube  being  invagiiiated ;  the 

1  Leuckart  proposed  the  term  lingula  ;  but  the  word  gives  rise  to  the  impression  that 
it  is  a  mistake  for  either  lingua  or  ligula.     Packard  calls  the  part  "  hypopharynx." 


i6 


IIVMENOPTERA 


CHAP. 


invaginated  part  can  be  thrust  out  by  increase  of  the  pressure  of 

the  fluid  in  the  tube.  A  portion 
of  the  wall  of  the  invaginate  part 
is  thickened  so  as  to  form  a  chiti- 
nous  rod. 

This  description  vail  suffice  for 
present  purposes,  as  the  other  parts 
of  the  mouth  will  be  readily  re- 
cognised by  the  aid  of  figure  9,  A, 
B,  C.  In  the  exquisitely  endowed 
South  American  genus  Euylossa  (Fig. 
18),  the  proboscis  is  somewhat  longer 
than  the  whole  of  the  body,  so  that 
its  tip  in  repose  projects  behind 
the  body  like  a  sting. 

The  correct  nomenclature  of  the 
parts  connected  with  the  lower  lip 
is  not  definitely  settled,  authorities 
not  being  agreed  on  several  points. 

FIG.  8. -Transverse  section  of  ligula  Tlle  wll°le  °f  the  P^OScis  is  USUally 

of    honey-bee,     diagram  atie.      A,  called    the   tongue  :    this,    however,    is 
With  the  long  sac  invaginate.    B.  . .,  •,.      ,. 

evagh.ate :  a,  chitinous  envelope  admittedly  an  erroneous  application 

with  the  bases  of  the  hairs ;  h,   of   ^1^    term.      The    terminal    deli- 
rod  ;  i;  groove  of  rod  ;  d,  lumen  .       . 

due  in  A  to  invagiuation  of  the  cate,   elongate,  flexible   organ    is    by 

rod,  iii  B  to  its  evagination  ;  u,    gome     canecj    the     tongue  ;     but     this 
nerve ;  tr,  trachea.  .  ... 

again     is     wrong :    the     lingua     in 

Insects  is  the  hypopharynx  ;  this  part  is  developed  in  a  peculiar 
manner  in  bees,  but  as  it  is  not  tongue-like  in  shape,  the  term 
lingua  is  not  suitable  for  it,  and  should  be  dismissed  altogether 
from  the  nomenclature  of  the  bee's  trophi ;  it  is  used  at  present 
in  two  different  senses,  both  of  which  are  erroneous.  We  see  no 
objection  to  describing  the  flexible  apical  portion  of  the  proboscis 
as  the  ligula.  The  lorum  is  probably  a  special  part  peculiar  to 
the  higher  bees ;  according  to  Saunders  it  is  not  present  as  a 
specialised  part  in  some  of  the  primitive  forms.1  The  application 
of  the  terms  mentuin,  submentum  and  hypoglottis  is  open  to  tin- 
same  doubts  that  exist  with  regard  to  them  in  so  many  other 


1  For  figures  and  descriptions  of  the  proboscides  of  British  bees,  refer  to  E.  Saun- 
ders, Jour.  Linn.  Xoe.  xxiii.  1890,  pp.  410-432,  plates  III.-X.  :  and  for  details  of 
the  minute  structure  ami  function  to  Cheshire,  /lees  and  Bee-keepiny,  vol.  i. 


BEES PROBOSCIS 


Insects,  and  we   have   omitted   the   term   hypogiottis  altogether, 
though  some  may  think  the  mentum  entitled  to  that  name. 

The  way  in  which  the  proboscis  of  the  bee  acts  has  been  very 
largely  discussed,  with 
special  reference  to  the 
question  as  to  whether  it  is 
a  sucking  or  a  licking  action. 
It  is  impossible  to  consider 
either  of  these  terms  as 
applicable.  The  foundation 
of  the  action  is  capillary 
attraction,  by  which,  and  by 
slight  movements  of  increase 
and  contraction  of  the 
capacity  of  various  parts,  the 
fluid  travels  to  the  cavity 
in  front  of  the  hypopharynx  : 
here  the  scales  of  the 
maxillae  leave  a  vacant 
space,  (Fig.  7,  e)  so  that  a 
cup  or  cavity  is  formed,  the 
fluid  in  which  is  within 
reach  of  the  tip  of  the  depen- 
dent epipharynx  (c),  which 
hangs  down  over  the  front 
of  the  hypopharynx  (and  is 
so  shaped  that  its  tip  covers 
the  cup) ;  it  is  between 
these  two  parts  that  the 
fluid  passes  to  reach  the 
pharynx.  It  is  no  doubt 
to  slight  movements  of  the 
membranous  parts  of  the 
hypopharynx  and  of  the 
epipharynx  that  the  further  progress  of  the  nectar  is  due,  aided 
by  contraction  and  expansion  of  the  pharynx,  induced  by  muscles 
attached  to  it.  It  should  be  recollected  that  in  addition  to  the 
movements  of  the  head  itself,  the  hypopharynx  is  constantly 
changing  its  dimensions  slightly  by  the  impulses  of  the  fluid  of 
the  general  body  cavity;  also  that  the  head  changes  its  position, 
VOL.  vi  c 


a- 


FIG.  9. — A,  Proboscis  of  a  "long-tongued  "  bee, 
Anthophora  pilipes ;  B,  lower,  C,  upper  view 

of   proboscis    of   an    "  obtuse-tougued "    bee 
Prosopis  pubescent,     u,   Labruni  ;  b,   stipes 
r,    palpiger  ;    d,    scale  :  f,   lobe  ;  g,   palpus 
h,  cardo,  of  maxilla :  i,  lorum  ;  k,  submentum 
/,  mentum  ;   m,   labial  palp  ;  •//,  paraglossa 
o,  ligula  ;  p.  tip  of  ligula  (with  "spoon  "  at  tip 
and  some  of  the  hairs  more  magnified)  ;  q, 
hypopharyngeal  sclerites. 


1 8  HYMENOPTERA 


CHAP. 


and  that  the  proboscis  is  directed  downwards  as  well  as  forwards. 
Those  who  wish  to  pursue  this  subject  should  refer  to  the  works 
of  Breithaupt l  and  Cheshire. 

The  other  external  characters  of  the  Bees  call  for  little  re- 
mark. The  pronotum  is  never  very  large  or  much  prolonged  in 
front,  and  its  hind  angles  never  repose  on  the  tegulae  as  they  do 
in  the  wasps,2  but  extend  backwards  below  the  tegulae.  The  hind 
body  is  never  narrowed  at  the  base  into  an  elongate  pedicel,  as  it 
so  frequently  is  in  the  Wasps  and  in  the  Fossors ;  and  the  pro- 
podeum  (the  posterior  part  of  the  thorax)  is  more  perpendicular 
and  rarely  so  largely  developed  as  it  is  in  the  Fossors  ;  this  last 
character  will  as  a  rule  permit  a  bee  to  be  recognised  at  a  glance 
from  the  fossorial  Hymenoptera. 

Bees,  as  every  one  knows,  frequent  flowers,  and  it  is  usually 
incorrectly  said  that  they  extract  honey.  They  really  gather 
nectar,  swallow  it,  so  that  it  goes  as  far  as  the  crop  of  their  ali- 
mentary canal,  called  in  English  the  honey-sac,  and  is  regurgi- 
tated as  honey.  Bertrand  states  that  the  nectar  when  gathered 
is  almost  entirely  pure  saccharose,  and  that  when  regurgitated  it 
is  found  to  consist  of  dextrose  and  levulose  : 3  this  change  appears 
to  be  practically  the  conversion  of  cane-  into  grape-sugar.  A 
small  quantity  of  the  products  of  the  salivary  glands  is  added, 
and  this  probably  causes  the  change  alluded  to ;  so  that  honey 
and  nectar  are  by  no  means  synonymous.  According  to  Cheshire 
the  glandular  matter  is  added  while  the  nectar  is  being  sucked, 
and  is  passing  over  the  middle  parts  of  the  lower  lip,  so  that 
the  nectar  may  be  honey  when  swallowed  by  the  bee.  In 
addition  to  gathering  nectar  the  female  bees  are  largely  occupied 
in  collecting  pollen,  which,  mixed  with  honey,  is  to  serve  as 
food  for  the  colony.  Many,  if  not  all,  bees  eat  pollen  while 
collecting  it.  The  mode  in  which  they  accumulate  the  pollen, 
and  the  mechanism  of  its  conveyance  from  hair  to  hair  till  it 
reaches  the  part  of  the  body  it  must  attain  in  order  to  be  removed 
for  packing  in  the  cells,  is  not  fully  understood,  but  it  appears 
to  be  accomplished  by  complex  correlative  actions  of  various  parts  ; 
the  head  and  the  front  legs  scratch  up  the  pollen,  the  legs  move 
with  great  rapidity,  and  the  pollen  ultimately  reaches  its  desti- 
nation. The  workers  of  the  genus  Apis,  and  of  some  other  social 

1    I'.rritli.'iiipt,  Arch.  Natunjrs.  lii.   I><1.  i.  ISSt!,  \>.  -17. 
2  See  Fig.  2fi.  p.  71.  3  Bull.  Mas.  Paris,  i.  1895,  p.  38. 


BEES HABITS  1,9 


bees,  have  the  basal  joint  of  the  hind  foot  specially  adapted  to 
deal  with  pollen  (Fig.  25,  2).  We  have  already  mentioned  the 
modifications  of  the  legs  used  for  its  conveyance,  and  need  here 
only  add  that  numerous  bees — the  Dasygastres — carry  the  pollen 
by  aid  of  a  special  and  dense  clothing  of  hairs  on  the  underside 
of  the  abdomen. 

The  buzzing  of  bees  (and  other  Insects)  has  been  for  long  a 
subject  of  controversy :  some  having  maintained  that  it  is  parti- 
ally or  wholly  due  to  the  vibration  of  parts  connected  with  the 
spiracles,  while  others  have  found  its  cause  in  the  vibrations  of 
the  wings.  According  to  the  observations  of  Perez  and  Bellesme,1 
two  distinct  sounds  are  to  be  distinguished.  One,  a  deep  noise, 
is  due  to  the  vibration  of  the  wings,  and  is  produced  whenever  a 
certain  rapidity  is  attained ;  the  other  is  an  acute  sound,  and  is 
said  to  be  produced  by  the  vibrations  of  the  walls  of  the  thorax, 
to  which  muscles  are  attached ;  this  sound  is  specially  evident 
in  Diptera  and  Hymeuoptera,  because  the  integument  is  of  the 
right  consistence  for  vibration.  Both  of  these  observers  agree  that 
the  spiracles  are  not  concerned  in  the  matter. 

The  young  of  bees  are  invariably  reared  in  cells.  These 
(except  in  the  case  of  the  parasitical  bees)  are  constructed  by 
the  mothers,  or  by  the  transformed  females  called  workers. 
The  solitary  bees  store  the  cells  with  food,  and  close  up  each  cell 
after  having  laid  an  egg  in  it,  so  that  in  these  cases  each  larva 
consumes  a  special  store  previously  provided  for  it.  The  social 
bees  do  not  close  the  cells  in  which  the  larvae  are  placed,  and 
the  workers  act  as  foster-mothers,  feeding  the  young  larvae  after 
the  same  fashion  as  birds  feed  their  nestling  young.  The  food  is 
a  mixture  of  honey  and  pollen,  the  mixing  being  effected  in  various 
ways  and  proportions  according  to  the  species  ;  the  honey  seems 
to  be  particularly  suitable  to  the  digestive  organs  of  the  young 
larvae,  and  those  bees  that  make  closed  cells,  place  on  the  outside 
f  the  mass  of  food  a  layer  more  thickly  saturated  with  honey, 
and  this  layer  the  young  grub  consumes  before  attacking  the 
drier  parts  of  the  provisions.  The  active  life  of  the  larva  is 
quite  short,  but  after  the  larva  is  full-grown  it  usually  passes  a 
more  or  less  prolonged  period  in  a  state  of  quiescence  before 
assuming  the  pupal  form.  The  pupa  shows  the  limbs  and  other 
parts  of  the  perfect  Insect  in  a  very  distinct  manner,  and  the 
1  C.R.  Ac.  Paris,  Ixxxvii.  1878,  pp.  378  and  535. 


o 


20  HYMENOPTERA  CHAP. 

development  of  the  imago  takes  place  gradually  though  quickly. 
Some  larvae  spin  cocoons,  others  do  not. 

A  very  large  number  of  bees  are  parasitic  in  their  habits, 
laying  an  egg,  or  sometimes  more  than  one,  in  the  cell  of  a  work- 
ing bee  of  some  species  other  than  their  own  ;  in  such  cases  the 
resulting  larvae  eat  and  grow  more  quickly  than  the  progeny  of 
the  host  bee,  and  so  cause  it  to  die  of  starvation.  It  has  been 
observed  that  some  of  these  parasitic  larvae,  after  eating  all  the 
store  of  food,  then  devour  the  larva  they  have  robbed.  In 
other  cases  it  is  possible  that  the  first  care  of  the  parasitic  larva, 
after  hatching,  is  to  eat  the  rival  egg. 

The  taxonomy  of  bees  is  in  a  very  unsatisfactory  state.  The 
earlier  Hyinenopterists  were  divided  into  two  schools,  one  of 
which  proposed  to  classify  the  bees  according  to  their  habits, 
while  the  other  adopted  an  arrangement  depending  on  the  length 
of  the  parts  of  the  mouth,  the  development  of  the  palpi,  and  the 
form  and  positions  of  the  organs  for  carrying  pollen.  Neither 
of  these  arrangements  was  at  all  satisfactory,  and  some  ento- 
mologists endeavoured  to  combine  them,  the  result  being  a 
classification  founded  partly  on  habits  and  partly  on  certain 
minor  structural  characters.  This  course  has  also  proved  unsatis- 
factory ;  this  is  especially  the  case  with  exotic  bees,  which  have 
been  placed  in  groups  that  are  defined  by  habits,  although  very 
little  observation  has  actually  been  made  on  this  point. 
Efforts  have  recently  been  made  to  establish  an  improved  classifi- 
cation, but  as  they  relate  solely  to  the  European  bees  they  are 
insufficient  for  general  purposes. 

The  more  important  of  the  groups  that  have  been  recognised 
are — (1)  the  Obtusilingues,  short-tongued  bees,  with  the  tip  of  the 
lingua  bifid  or  broad;  (2)  Acutilingues,  short-tongued  bees,  with 
acute  tip  to  the  tongue  ;  these  two  groups  being  frequently  treated 
of  as  forming  the  Andrenidae.  Coming  to  the  Apidae,  or  the 
bees  with  long  and  folded  tongues,  there  have  been  distinguished 
(3)  Scopulipedes,  bees  carrying  pollen  with  their  feet,  and  (4) 
I>asygastres,  those  that  carry  it  under  the  abdomen;  some  of  the 
p;irasitie  and  other  forms  have  been  separated  as  (5)  Denudatae 
(or  ( 'iietilinae) :  the  l>ombi  and  the  more  perfectly  social  bees 
forming  another  group,  viz.  (G)  Sociales.  A  group  Andrenoides, 
or  Pan  urg  ides,  was  also  proposed  for  certain  bees  considered  to 
belong  to  the  Apidae  though  exhibiting  many  points  of  resent- 


i  BEES — ARCHIAPIDES  21 

blance  with  the  Andrenidae.  This  arrangement  is  by  no  means 
satisfactory,  but  as  the  tropical  bees  have  been  but  little  collected, 
and  are  only  very  imperfectly  known,  it  is  clear  that  we  cannot 
hope  for  a  better  classification  till  collections  have  been  very 
much  increased  and  improved.  The  arrangement  adopted  in 
Dalla  Torre's  recent  valuable  catalogue  of  bees1  recognises  no  less 
than  fourteen  primary  divisions,  but  is  far  from  satisfactory. 

The  two  genera  Prosopis  and  Spliecodcs  have  been  recently 
formed  into  a  special  family,  AKCHIAPIDAE,  by  Friese,2  who,  how- 
ever, admits  that  the  association  is  not  a  natural  one.  The 
term  should  be  limited  to  Prosopis  and  the  genera  into  which  it 
has  been,  or  shortly  will  be,  divided.  The  primitive  nature  of 
the  members  of  this  genus  is  exhibited  in  all  the  external 
characters  that  are  most  distinctive 
of  bees;  the  proboscis  (Fig.  9,  B,  C),  is 
quite  short,  its  ligula  being  very  short, 
and  instead  of  being  pointed  having 
a  concave  front  margin.  The  body 
is  almost  bare,  though  there  is  some 
very  short  feathered  plumage.  The 
hind  legs  are  destitute  of  modifica- 
tions for  industrial  purposes.  Owing 
to  these  peculiarities  it  was  for 

long     assumed    that     the    species     Of   FIG.     10.  —  Prosopis   signata.      Cam- 

PfOSOpis    must    be    parasites.         This          bridp     A,   Female;   B    front  of 

head  of  female  ;  C,  of  male. 

is,  however,  known   not   to  be  the 

case  so  far  as  many  of  the  species  are  concerned.  They  form 
cells  lined  with  a  silken  membrane  in  the  stems  of  brambles 
and  other  plants  that  are  suitable,  or  in  burrows  in  the 
earth,  or  in  the  mortar  of  walls ;  individuals  of  the  same  species 
varying  much  as  to  the  nidus  they  select.  The  food  they  store 
in  these  cells  is  much  more  liquid  than  usual,  and  has  been 
supposed  to  be  entirely  honey,  since  they  have  no  apparatus  for 
carrying  pollen.  Mr.  E,  C.  L.  Perkins  has,  however,  observed 
that  they  swallow  both  pollen  and  nectar,  brushing  the  first- 
named  substance  to  the  mouth  by  aid  of  the  front  legs.  He 

1   Catalogus  Hymcnoptcrorum,  Leipzig,  10  vols.  1892-96  ;  Bees,  vol.  x. 

-  Zool.  Jahrb.  Syst.  iv.  1891,  p.  779.  This  paper  is  a  most  valuable  summary 
of  what  is  known  as  to  the  habits  of  European  solitary  bees,  but  is  less  satisfactory 
from  a  systematic  point  of  view. 


22  IIYMENOPTERA  CHAP. 

has  ascertained  that  a  few  of  the  very  numerous  Hawaiian  species 
of  the  genus  are  really  parasitic  on  their  congeners  :  these  parasites 
are  destitute  of  a  peculiar  arrangement  of  hairs  on  the  front 
legs  of  the  female,  the  possession  of  which,  Ly  some  of  the  non- 
parasitic  forms,  enables  the  bee  to  sweep  the  pollen  towards  its 
mouth.  These  observations  show  that  the  structural  peculiarities 
of  I'rosojtis  are  correlative  with  the  habits  of  forming  a  peculiar 
lining  to  the  cell,  and  of  gathering  pollen  by  the  mouth  and 
conveying  it  by  the  alimentary  canal  instead  of  by  external  parts 
of  the  body.  Prosopis  is  a  very  widely  distributed  genus,  and 
very  numerous  in  species.  We  have  ten  in  Britain  ;  several  of 
them  occur  in  the  grounds  of  our  Museum  at  Cambridge. 

The  species  of  the  genus  Colletes  are  hairy  bees  of  moderate 
size,  with  a  good  development  of  hair  on  the  middle  and  posterior 
femora  for  carrying  pollen.  They  have  a  short,  bilobed  ligula 
like  that  of  wasps,  and  therein  differ  from  the  Andrenae,  which 
they  much  resemble.  With  Prosopis  they  form  the  group  Obtusi- 
lingues  of  some  taxonomists.  They  have  a  manner  of  nesting 
peculiar  to  themselves ;  they  dig  cylindrical  burrows  in  the 
earth,  line  them  with  a  sort  of  slime,  that  dries  to  a  substance 
like  gold-beater's  skin,  and  then  by  partitions  arrange  the 
burrow  as  six  to  ten  separate  cells,  each  of  which  is  filled 
with  food  that  is  more  liquid  than  usual  in  bees.  Except  in 
regard  to  the  ligula  and  the  nature  of  the  cell-lining,  Colletes  has 
but  little  resemblance  to  Prosopis;  but  the  term  Obtusilingurs 
may  be  applied  to  Colletes  if  Prosopis  be  separated  as  Archiapidae. 
We  have  six  species  of  Colletes  in  Britain. 

Sphecodes  is  a  genus  that  has  been  the  subject  of  prolonged 
< inference  of  opinion.  The  species  are  rather  small  shining 
bees,  with  a  red,  or  red  and  black,  abdomen,  almost  with- 
out pollen-collecting  apparatus,  and  with  a  short  but  pointed 
ligula.  These  characters  led  to  the  belief  that  the  Insects  are 
parasitic,  or,  as  they  are  sometimes  called,  cuckoo-bees.  But 
evidence  could  not  be  obtained  of  the  fact,  and  as  they  were  seen 
to  make  burrows  it  was  decided  that  we  have  in  Spheco</<x 
examples  of  industrial  bees  extremely  ill  endowed  for  their  work. 
Recent  observations  tend,  however,  to  prove  that  fyrfiecodes  are  to 
a  large  extent  parasitic  at  the  expense  of  bees  of  the  genera 
I  ful  id  us  and  A  ml  re  mi.  Breitenbach  has  taken  S.  rubicundus  out 
of  the  brood-cells  of  Halictus  quadricinctus  ;  and  on  one  of  the  few 


BEES ANDRENIDES  23 


occasions  on  which  this  bee  has  been   found  in  Britain  it  was   in 
circumstances  that  left  little  doubt  as  to  its  being  a  parasite  of 
Andrcna   niyroaenca.      Marchal l  has   seen  S.  subquadratus    fight 
with     Halietas    malachurus, 
and  kill  it  previous  to  taking 
possession    of    its    burrows ; 
and      similar      observations 
have   been   made  by  Ferton. 
As  the  older  observations  of 
Smith,    Sichel,    and     Friese 
leave  little  doubt  that  Sphe- 
codes  are    sometimes   indus- 
trial bees,  it  is  highly  prob- 
able that  we    have   in    this 

FIG.  11. — Sphecodes  gibbus  9-  Britain. 
genus  the  interesting  con- 
dition of  bees  that  are  sometimes  parasitic,  at  other  times 
not ;  but  so  much  obscurity  still  prevails  as  to  the  habits  of 
Sphecodes  that  we  should  do  well  to  delay  accepting  the  theories 
that  have  been  already  based  on  this  strange  state  of  matters.2 
Friese  states  that  in  Sphecodes  the  first  traces  of  collecting- 
apparatus  exist ;  and,  accepting  the  condition  of  affairs  as  being 
that  mentioned  above,  it  is  by  no  means  clear  whether  we  have 
in  Sphecodes  bees  that  are  abandoning  the  parasitic  habit  or  com- 
mencing it ;  or,  indeed,  whether  the  condition  of  uncertainty 
may  not  be  a  permanent  one.  It  is  difficult  to  decide  as  to 
what  forms  are  species  in  Sphecodes  owing  to  the  great  variation. 
The  Hymenopterist  Forster  considered  that  600  specimens  sub- 
mitted to  him  by  Sichel  represented  no  less  than  140  species, 
though  Sichel  was  convinced  that  nearly  the  whole  of  them 
were  one  species,  S.  gibbus.  It  has  recently  been  found  that  the 
male  sexual  organs  afford  a  satisfactory  criterion.  The  position 
of  Sphecodes  in  classification  is  doubtful. 

The  great  majority  of  the  species  of  short-tongued  bees  found  in 
Britain  belong  to  the  genera  Andrena  and  Halictus,  and  with  some 
others  constitute  the  ANDRENIDES  of  many  writers.  Halictus 
includes  our  smallest  British  bees.  Their  economy  escaped  the 
earlier  observers,  but  has  recently  been  to  some  extent  unravelled 
by  Smith,  Fabre,  Nicolas,  Verhoeff,  and  others,  and  proves  to  be 

1  Bull.  Soc.  ent.  France,  1894,  p.  cxv. 
-  Marchal,  Rev.  Sci.  15th  February  1890,  and  Ferton,  t.c.  19th  April. 


24  HYMENOFTKRA  CHAP. 

of  great  interest  and  variety.  Fabre  observed  H.  lineolatus  and 
H.  sexcinctus  1  under  circumstances  that  enabled  him  to  give  them 
continuous  attention,  whenever  requisite,  throughout  a  whole  year. 
These  bees  are  to  a  certain  extent  social ;  they  are  gregarious  ;  each 
bee  works  for  its  own  progeny,  but  there  is  collaboration  between 
members  of  a  colony,  inasmuch  as  a  piece  of  general  work  is 
undertaken  from  which  more  families  than  one  derive  benefit. 
This  common  work  is  a  gallery,  that,  ramifying  in  the  earth, 
gives  access  to  various  groups  of  cells,  each  group  the  production 
of  a  single  Halictus  ;  in  this  way  one  entrance  and  one  corridor 
serve  for  several  distinct  dwellings.  The  work  of  excavation  is 
carried  on  at  night.  The  cells  are  oval,  and  are  covered  on  the 
interior  with  a  delicate  waterproof  varnish  ;  Fabre  considers  this 
to  be  a  product  of  the  salivary  glands,  like  the  membrane  we 
noticed  when  speaking  of  Colletes.  In  the  south  of  France  both 
sexes  of  these  species  are  produced  from  the  nests  in  September, 
and  then  the  males  are  much  more  numerous  than  the  females ; 
when  the  cold  weather  sets  in  the  males  die,  but  the  females 
continue  to  live  on  in  the  cells  underground.  In  the  following 
spring  the  females  come  out  and  recommence  working  at  the 
burrows,  and  also  provision  the  cells  for  the  young ;  the  new 
generation,  consisting  entirely  of  females,  appears  in  July,  and 
from  these  there  proceeds  a  parthenogenetic  generation,  which 
assumes  the  perfect  form  in  September,  and  consists,  as  we  have 
above  remarked,  in  greater  part  of  males.  Perez,2  however, 
considers  that  Fabre's  observations  as  to  the  parthenogenetic 
generation  were  incomplete,  and  that  males  might  have  been 
found  a  little  earlier,  and  he  consequently  rejects  altogether 
the  occurrence  of  parthenogenesis  in  Halictus.  Nicolas  con- 
firms Fabre's  observations,  so  far  as  the  interesting  point  of  the 
work  done  for  common  benefit  is  concerned ;  and  adds  that  the 
common  corridor  being  too  narrow  to  permit  of  two  bees  passing, 
there  is  a  dilatation  or  vestibule  near  the  entrance  that  facilitates 
passage,  and  also  that  a  sentinel  is  stationed  at  this  point. 

Smith's  observations  on  Halictus  morio  in  England  lead  one 
to  infer  that  there  is  but  one  generation,  the  appearance  of  which 
extends  over  a  very  long  period.  He  says,  "  Early  in  April  the 
females  appeared,  and  continued  in  numbers  iip  to  the  end  of 

1   C.R.  Ac.  Paris,  Ixxxix.  1879,  p.  1079,  and  Ann.  Set.  Nut.  ((>),  ix.  1879,  Xo.  4. 
2  Act.  8uc.  Bordeaux,  xlviii.  1895,  p.  145. 


BEES ANDRENIDES 


June  "  ;  then  there  was  an  interval,  and  in  the  middle  of  August 
males  began  to  appear,   followed   in   ten 
or  twelve  days  by  females.     Hence  it  is      \/ 
probable  that  in  different  countries   the 
times  of  appearance  and  the  number  of  .;-.\% :--.f^~'V'~r^f 

generations  of  the  same  species  may  vary.  /^ 7  | 

Yerhoeff  has  described  the  burrows  of 
Halictus  quadricinctus  with  some  detail. 
The  cells,  instead  of  being  distributed 
as  usual  throughout  the  length  of  the 
burrow  one  by  one,  are  accumulated 
into  a  mass  placed  in  a  vault  communi- 
cating with  the  shaft.  This  shaft  is 
continued  downwards  to  a  depth  of  10 
cm.,  and  forms  a  retreat  for  the  bees 
when  engaged  in  construction.  Several 
advantages  are  secured  by  this  method, 
especially  better  ventilation,  and  pro- 
tection from  any  water  that  may  enter  FIG.  12.— Nesting  of 
the  shaft.  The  larvae  that  are  present  ^T^h  ^±Tl 
in  the  brood-chambers  at  any  one 
moment  differ  much  in  their  ages,  a 
fact  that  throws  some  doubt  011  the 
supposed  parthenogenetic  generation. 
No  cocoons  are  formed  by  these  Halictus, 

the  polished  interior  of  the  cell  being  a  sufficiently  refined  resting 
place  for  metamorphosis.  Yerhoeff  states  that  many  of  the 
larvae  are  destroyed  by  mouldiness ;  this  indeed,  he  considers  to 
lie  the  most  deadly  of  the  enemies  of  Aculeate  Hymenoptera. 
The  nest  of  Halictus  maculatus  has  also  been  briefly  described 
by  Yerhoeff,  and  is  a  very  poor  construction  in  comparison  with 
that  of  H.  quadricinctus. 

The  genus  Andrena  includes  a  great  number  of  species, 
Britain  possessing  about  fifty.  They  may  be  described  in  a 
general  manner  as  Insects  much  resembling  the  honey-bee— 
for  which,  indeed,  they  are  frequently  mistaken — but  usually  a 
little  smaller  in  size.  Many  of  the  bees  we  see  in  spring,  in 
March  or  April,  are  of  this  genus.  They  live  in  burrows  in  the 
ground,  preferring  sandy  places,  but  frequently  selecting  a  gravel 
path  as  the  locality  for  their  operations ;  they  nearly  always  live 


thereto  ;  n,  retreat  or  con- 
tinuation of  the  burrow  ;  w, 
the  vaults  ;  s,  the  accumula- 
tion of  cells.  (After  Ver- 
hoeff, Verh.  Ver.  Rheinl.  xlviii. 
1891  ;  scale  not  mentioned.) 


26 


HYMENOPTERA 


CHAP. 


in  colonies.  Great  difficulties  attend  their  study  on  account  of 
several  points  in  their  economy,  such  as,  that  the  sexes  are 
different,  and  frequently  not  found  together ;  also  that  there  may 
be  two  generations  of  a  species  in  one  year,  these  being  more  or 
less  different  from  one  another.  Another  considerable  difficulty 
arises  from  the  fact  that  these  bees  are  subject  to  the  attacks  of 
the  parasite  Sti/lops,  by  which  their  form  is  more  or  less  altered. 

1  i/         -L        '          v 

These  Insects  feed  in  the  body  of  the  bee  in  such  a  way  as  to 
affect  its  nutrition  without  destroying  its  life  ;  hence  they  offer  a 
means  of  making  experiments  that  may  throw  valuable  light  on 
obscure  physiological  questions.  Among  the  effects  they  produce 
in  the  condition  of  the  imago  bee  we  may  mention  the  enfeeble- 
ment  of  the  sexual  distinction,  so  that  a  stylopised  male  bee 
becomes  less  different  than  it  usually  is  from  the  female,  and  a 
stylopised  female  may  be  ill  developed  and  less  different  than 
usual  from  the  male.  The  colours  and  hair  are  sometimes  altered, 
and  distortion  of  portions  of  the  abdominal  region  of  the  bee  are 
very  common.  Further  particulars  as  to  these  parasites  will  be 
found  at  the  end  of  our  account  of  Coleoptera  (p.  298).  We  may 
here  remark  that  these  Stylops  are  not  the  only  parasitic  Insects 
that  live  in  the  bodies  of  Andrenidae  without  killing  their  hosts, 
or  even  interrupting  their  metamorphoses.  Mr.  E.  C.  L.  Perkins 

recently  captured  a  specimen  of  Halictus 
rul)icundus,fcom  which  he,  judging  from  the 
appearance  of  the  example,  anticipated  that 
a  Stylops  would  emerge  ;  but  instead  of  this 
a  Dipterous  Insect  of  the  family  Chloropidae 
appeared.  Dufour  in  1837  called  attention 
to  a  remarkable  relation  existing  between 
Andrena  aterrimaand  a  parasitic  Dipterous 
larva.  The  larva  takes  up  a  position  in 
the  interior  of  the  bee's  body  so  as  to  be 
partly  included  in  one  of  the  great  tracheal 
FIG.  13.— Parasitic  Dipterous  vesicles  at  the  base  of  the  abdomen ;  and 
larva  in  connection  with  the  bee  then  maintams  the  parasite  in  its 

tracheal    system    of    An-  _ r 

Arena   aterrima.      (After  position,  and  at  the  same  time  supplies  it 

with  air  by  causing  two  tracheae  to  grow 

into  its  body.  Dufour  states  that  he  demonstrated  the  continuity 
of  the  tracheae  of  the  two  organisms,  but  it  is  by  no  means  clear 
that  the  continuity  was  initially  due  to  the  bee's  organisation. 


BEES ANDRENIDES 


Dasypoda  hirtipes  appears  to  be  the  most  highly  endowed  of 
the  European  Andrenides.  The 
Insects  of  the  genus  Dasypoda 
are  very  like  Andrena,  but 
have  only  two  in  place  of  three 
submarginal  cells  (just  beneath 
the  stigma)  on  the  front  wing. 
The  female  of  D.  hirtipes  has  a 
very  dense  and  elongate  pubes- 
cence on  the  posterior  legs,  and 


FIG.  14. — D.  hirtipes  9.     Britain. 


carries  loads  of  pollen, each  about 
half  its  own  weight,  to  its  nest. 
The  habits  of  this  insect  have  been  described  by  Hermann 
Mtiller.1  It  forms  burrows  in  the  ground  after  the  fashion  of 
Andrena ;  this  task  is  accomplished  by  excavating  with  the 
mandibles  ;  when  it  has  detached  a  certain  quantity  of  the  earth 
it  brings  this  to  the  surface  by  moving  backwards,  and  then  dis- 
tributes the  loose  soil  over  a  considerable  area.  It  accomplishes 
this  in  a  most  beautiful  manner  by  means  of  the  combined  action 
of  all  the  legs,  each  pair  of  these  limbs  performing  its  share  of 
the  function  in  a  different  manner ;  the  front  legs  acting  with 
great  rapidity — making  four  movements  in  a  second — push  the 
sand  backwards  under  the  body,  the  bee  moving  itself  at  the 
same  time  in  this  direction  by  means  of  the  middle  pair  of  legs ; 
simultaneously,  but  with  a  much  slower  movement,  the  hind  legs 
are  stretched  and  moved  outwards,  in  oar-like  fashion,  from  the 
body,  and  thus  sweep  away  the  earth  and  distribute  it  towards 
each  side.  This  being  done  the  bee  returns  quickly  into  the  hole, 
excavates  some  more  earth,  brings  it  up  and  distributes  it.  Each 
operation  of  excavation  takes  a  minute  or  two,  the  distribution 
on  the  surface  only  about  fifteen  seconds.  The  burrow  extends 
to  the  length  of  one  or  two  feet,  so  that  a  considerable  amount  of 
earth  has  to  be  brought  up  ;  and  when  the  Insect  has  covered  one 
part  of  the  circumference  of  the  mouth  of  the  hole  with  loose 
earth,  it  makes  another  patch,  or  walk,  by  the  side  of  the  first. 
The  main  burrow  being  completed,  the  Insect  then  commences 
the  formation  of  brood-chambers  in  connection  with  it.  Three  to 
six  such  chambers  are  formed  in  connection  with  a  burrow  ;  the 
lower  one  is  first  made  and  is  provisioned  by  the  bee  :  for  this 

1   J'crh.  Vcr.  Eheinland,  xli.  1884,  p.  1. 


28  HYMENOPTERA  CHAP. 

purpose  five  or  six  loads  of  pollen  are  brought   to  the  cell,  each 
load  being,  as  we  have   already  remarked,  about  half  the  weight 
of  the  Insect.      This  material  is  then  formed  into  a  ball  and  made 
damp  with  honey  ;   then  another  load  of  pollen  is  brought,  is 
mixed  with  honey  and  added  as  an  outer  layer  to  the  ball,  which 
is  now  remodelled  and  provided  on  one  side  with  three  short  feet, 
after  which  an  egg  is  placed  on   the  top   of  the   mass  ;  the  bin- 
then   sets    to   work   to    make    a   second   chamber,  and    uses   the 
material  resulting  from  the  excavation  of  this  to  close  completely 
the  first  chamber.      The  other  chambers  are  subsequently  formed 
in   a   similar    manner,  and   then   the   burrow  itself  is   filled  up. 
While   engaged  in   ascertaining    these   facts,    Miiller    also    made 
some    observations    on    the    way   the   bee   acts   when   disturbed 
in    its    operations,    and    his    observations    on  this    point    show 
a    very    similar    instinct    to    that    displayed    by    Ckalicodoma, 
referred  to  on  a  subsequent  page.      If  interrupted  while  storing  a 
chamber    the   Insect  will   not  attempt  to  make  a  fresh  one,  but 
will    carry   its   stock   of    provisions   to   the   nest   of   some   other 
individual.      The  result  of  this  proceeding  is  a  struggle  between 
the   two   bees,  from   which   it   is   satisfactory  to    learn   that   the 
rightful  proprietor  always  comes  out  victorious.      The  egg  placed 
on  the  pollen-ball  in  the  chamber  hatches   in  a  few  days,  giving 
birth   to  a  delicate  white  larva  of  curved   form.      This  creature 
embraces  the  pollen-ball  so  far  as  its  small  size  will  enable  it  to 
do  so,    and  eats  the  food   layer  by  layer   so  as   to  preserve  its 
circular    form.      The    larva    when    hatched    has    no    anal    orifice 
and  voids    no    excrement,  so    that  its   food  is  not  polluted  ;    a 
proper   moulting   apparently  does   not   take   place,  for   though   a 
new  delicate  skin  may  be  found  beneath  the  old  one  this  latter  is 
nut  definitely  cast  off.      When  the  food,  which  was  at  first  100 
to  140  times  larger  than  the  egg  or  young  larva,  is  all  consumed 
the  creature  then  for  the  first  time  voids  its  refuse.      During 
its  orowth  the  larva  becomes  red  and  increases  in  weight  from  '0025 

O  <J 

grains  to  '26  or  '35  grains,  but  during  the  subsequent  period  of 
excretion  it  diminishes  to  '09  or  '15  grains,  and  in  the  course  of 
doing  so  becomes  a  grub  without  power  of  movement,  and  of  a 
white  instead  of  a  red  colour.  After  this  the  larva  reposes 
motionless  for  many  months — in  fact,  until  the  next  summer,  when 
it  throws  off  the  larval  skin  and  appears  as  a  pupa.  The  larval 
skin  thus  cast  off  contrasts  greatly  with  the  previous  delicate  coiuli- 


BEES DENUDATAE  29 


tion  of  the  integument,  for  this  last  exuvium  is  thick  and  ri<dd. 

o  o 

Although  it  voids  no  excrement  till  much  later  the  union  of  the 
stomach  and  hind-intestine  is  accomplished  when  the  larva  is 
half-grown.  A  larva,  from  which  Miiller  took  away  a  portion  of 
its  unconsumed  food -store,  began  directly  afterwards  to  emit 
excrement.  The  pupa  has  greater  power  of  movement  than 
the  resting  larva ;  when  it  has  completed  its  metamorphosis 
and  become  a  perfect  Insect,  it,  if  it  be  a  female,  commences 
almost  immediately  after  its  emergence  to  form  burrows  by  the 
complex  and  perfect  series  of  actions  we  have  described. 

Parasitic  Bees  (DENUDATAE). — This  group  of  parasitic  bees 
includes  fourteen  European  genera,  of  which  six  are  British. 
They  form  a  group  taxonomically  most  unsatisfactory,  the 
members  having  little  in  common  except  the  negative  characters 
of  the  absence  of  pollen-carrying  apparatus.  Although  there 
is  a  great  dearth  of  information  as  to  the  life -histories  of 
parasitic  bees,  yet  some  highly  interesting  facts  and  generalisa- 
tions about  their  relations  with  their  hosts  have  already  been 

t/ 

obtained.  Verhoeff  has  recently  given  the  following  account  of 
the  relations  between  the  parasitic  bee  Stelis  minuta  and  its 
host  Osmia  leucomelana : — The  Osmia  forms  cells  in  blackberry 
stems,  provisions  them  in  the  usual  manner,  and  deposits  an 
egg  in  each.  But  the  Stelis  lays  an  egg  in  the  store  of  pro- 
visions before  the  Osmia  does,  and  thus  its  egg  is  placed  lower 
down  in  the  mass  of  food  than  that  of  the  legitimate  owner, 
which  is  in  fact  at  the  top.  The  Stelis  larva  emerges  from  the 
egg  somewhat  earlier  than  the  Osmia  larva  does.  For  a  con- 
siderable time  the  two  larvae  so  disclosed  consume  together  the 
stock  of  provisions,  the  Osmia  at  the  upper,  the  Stelis  at  the  lower, 
end  thereof.  By  the  consumption  of  the  provisions  the  two  larvae 
are  brought  into  proximity,  and  by  this  time  the  Stelis  larva,  being 
about  twice  the  size  of  the  Osmia  larva,  kills  and  eats  it.  Verhoeff 
witnessed  the  struggle  between  the  two  larvae,  and  states  further 
that  the  operation  of  eating  '  the  Osmia  larva  after  it  has  been 
killed  lasts  one  or  two  days.  He  adds  that  parasitic  larvae  are 
less  numerous  than  the  host  larvae,  it  being  well  known  that 
parasitic  bees  produce  fewer  offspring  than  host  bees.  Verhoeff 
further  states  that  he  has  observed  similar  relations  to  obtain 
between  the  larvae  of  other  parasitic  bees'and  their  hosts,  but  warns 
us  against  concluding  that  the  facts  are  analogous  in  all  cases. 


10 


HYMENOPTERA 


CHAP. 


FIG.  15. — Nbmada  sex-fasriata  9- 

Britain. 


Fabre  has  made  as  acquainted  with  some  points  in  the  history  of 
another  species  of  the  same  genus,  viz.  Stelis  nasuta,  that  show  a 
decided  departure  from  the  habits  of  S.  minuta.  The  first-named 
Insect  accomplishes  the  very  difficult  task  of  breaking  open  the  cells 
of  the  mason-bee,  Chalicodoma  muraria,  after  they  have  been  sealed 
up,  and  then,  being  an  Insect  of  much  smaller  size  than  the  Chali- 
codoma, places  several  eggs  in  one  cell  of  that  bee.  Friese  informs 
us  that  parasitic  bees  and  their  hosts,  in  a  great  number  of  cases, 
not  only  have  in  the  perfect  state  the  tongue  similarly  formed, 

but  also  frequent  the  same  species 
of  flower  ;  thus  Colletcs  davicsanus 
and  its  parasite  Epeolus  variegatus 
both  specially  affect  the  flowers  of 
Tanacetum  vulyare.  Some  of  the 
parasitic  bees  have  a  great  resem- 
blance to  their  hosts  ;  Stelis  signata, 
for  instance,  is  said  to  be  so  like 
Antliidiiim  strigatum  that  for  many 
years  it  was  considered  to  be  a 
species  of  the  genus  Anthidium. 
In  other  cases  not  the  least  resemblance  exists  between  the 
parasites  and  hosts.  Thus  the  species  of  Nomada  that  live  at 
the  expense  of  species  of  the  genus  Andre  no,  have  110  resemblance 
thereto.  Friese  further  tells  us  that  the  Andrena  and  Nomada 
are  on  the  most  friendly  terms.  Andrena,  as  is  well  known, 
forms  populous  colonies  in  banks,  paths,  etc.,  and  in  these  colonies 
the  destroying  Nomada  flies  about  unmolested  ;  indeed,  according 
to  Friese,  it  is  treated  as  a  welcome  guest.  He  says  he  has  often 
seen,  and  in  several  localities,  Nomada  lathburiana  and  Andrena 
ovina  flying  peacefully  together.  The  Nome  da  would  enter  a 
burrow,  and  if  it  found  the  Andrena  therein,  would  come  out  and 
try  another  burrow  ;  if  when  a  marauding  Nomada  was  in  a 
burrow,  and  the  rightful  owner,  returning  laden  with  pollen, 
found  on  entering  its  home  that  an  uninvited  guest  was  therein, 
the  Andrena  would  go  out  in  order  to  permit  the  exit  of  the 
Nomada,  and  then  would  again  enter  and  add  the  pollen  to  the 
store.  Strange  as  this  may  seem  at  first  sight,  it  is  really  not 
so,  for,  as  we  have  before  had  occasion  to  observe,  there  is  not  the 
slightest  reason  for  believing  that  host  Insects  have  any  idea 
whatever  that  the  parasites  or  iiiquilines  are  injurious  to  their 


i  PARASITIC  BEES DENUDATAE  31 

race.  Why  then  should  they  attack  the  creatures  ?  Provided  the 
parasites  do  not  interfere  in  any  unmannerly  way  with  the  hosts 
and  their  work,  there  is  no  reason  why  the  latter  should  resent 
their  presence.  The  wild  bee  that  seals  up  its  cell  when  it  has 
laid  an  egg  therein,  and  then  leaves  it  for  ever,  has  no  conception 
of  the  form  of  its  progeny  ;  never  in  the  history  of  the  race  of  the 
Andrena  has  a  larva  seen  a  perfect  insect  and  survived  thereafter, 
never  has  a  perfect  Insect  seen  a  larva.  There  is  no  reason  what- 
ever for  believing  that  these  Insects  have  the  least  conception  of 
their  own  metamorphosis,  and  how  then  should  they  have  any 
idea  of  the  metamorphosis  of  the  parasite  ?  If  the  Andrena  found 
in  the  pollen  the  egg  of  a  parasitic  Nomada,  it  could  of  course 
easily  remove  the  egg ;  but  the  Andrena  has  no  conception 
that  the  presence  of  the  egg  ensures  the  death  of  its  own 
offspring  and  though  the  egg  be  that  of  an  enemy  to  its  race, 
why  should  it  resent  the  fact  ?  Is  it  not  clear  that  the  race  has 
always  maintained  itself  notwithstanding  the  enemy  ?  Nature  has 
brought  about  that  both  host  and  parasite  should  successfully 
co-exist ;  and  each  individual  of  each  species  lives,  not  for  itself, 
but  for  the  continuance  of  the  species ;  that  continuance  is  pro- 
vided for  by  the  relative  fecundities  of  host  and  guest.  Why 
then  should  the  Andrena  feel 
alarm  ?  If  the  species  of  Nomada 
attack  the  species  of  Andrena  too 
much  it  brings  about  the  de- 
struction of  its  own  species 
more  certainly  than  that  of  the 
Andrena. 

Such  extremely  friendly  rela- 
tions do  not,  however,  exist  be- 
tween all  the  parasitic  bees  and 

FIG.  16. — Melecta  luctuosa  ?.     Britain. 

their  hosts.      Friese  says  that,  so 

far  as  he  has  been  able  to  observe,  the  relations  between  the  two 
are  not  in  general  friendly.  He  states  that  marauders  of  the 
genera  Melecta  and  Coelioxys  seek  to  get  out  of  the  way  when 
they  see  the  pollen-laden  host  coming  home.  But  he  does  not 
appear  to  have  noted  any  other  evidence  of  mistrust  between  the 
two,  and  it  is  somewhat  doubtful  whether  this  act  can  properly 
be  interpreted  as  indicating  fear,  for  bees,  as  well  as  other 
animals,  when  engaged  in  work  find  it  annoying  to  be  interfered 


32  HYMENOPTERA  CHAP. 

with  ;  it  is  the  interest  of  the  parasite  to  avoid  annoyance  and  to 
be  well-mannered  in  its  approaches.  Shuckard,  however,  says  that 
battles  ensue  between  the  parasite  Melecta  and  its  host  Anthopliora, 
when  the  two  bees  meet  in  the  burrows  of  the  Anthophora.1 

We  shall  have  occasion  to  remark  on  some  of  the  habits  of 
Dioxys  cincta  when  considering  the  history  of  the  mason -bee 
(Chalicodoma),  but  one  very  curious  point  in  its  economy  must 
here  be  noticed.  The  Dioxys,  which  is  a  much  smaller  bee  than 
the  Chalicodoma,  lays  an  egg  in  a  cell  of  the  latter,  and  the 
resulting  larva  frequently  has  more  food  in  the  cell  than  it  can 
consume  ;  there  is,  however,  another  bee,  Osmia  cyanoxantlia,  that 
frequently  takes  advantage  of  an  unoccupied  cell  in  the  nest 
of  the  Chalicodoma,  and  establishes  its  own  offspring  therein. 
The  Dioxys,  it  seems,  cannot,  or  at  any  rate  does  not,  distinguish 
whether  a  cell  is  occupied  by  Chalicodoma  or  by  Osmia,  and  some- 
times lays  its  egg  in  the  nest  of  the  Osmia,  though  this  bee  is 
small,  and  therefore  provides  very  little  food  for  its  young.  It 
might  be  supposed  that  under  these  conditions  the  Dioxys  larva 
would  be  starved  to  death ;  but  this  is  not  so  ;  it  has  the  power 
of  accommodating  its  appetite,  or  its  capacity  for  metamorphosis, 
to  the  quantity  of  food  it  finds  at  its  disposal,  and  the  egg  laid  in 
the  Osmia  cell  actually  produces  a  tiny  specimen  of  Dioxys,  only 
about  half  the  natural  size.  Both  sexes  of  these  dwarf  Dioxys  are 
produced,  offering  another  example  of  the  fact  that  the  quantity 
of  food  ingested  during  the  lifetime  of  the  larva  does  not  influ- 
ence the  sex  of  the  resulting  imago. 

The  highly  endowed  bees  that  remain  to  be  considered  are 
by  some  writers  united  in  a  group  called  Apidae,  in  distinction 
from  Andrenidae.  For  the  purposes  of  this  work  we  shall  adopt 
three  divisions,  Scopulipedes,  Dasygastres,  Sociales. 

The  group  SCOPULIPEDES  includes  such  long-tongued,  solitary 
bees  as  are  not  parasitic,  and  do  not  belong  to  the  Dasygastres. 
It  is  not,  however,  a  natural  group,  for  the  carpenter-bees 
(Xylocopa)  are  very  different  from  Anthopliora.  It  has 
recently  been  merged  by  Friese  with  Andrenides  into  a  single 
group  called  Podilegidae.  Four  British  genera,  Ceratina,  AnfJio- 
pliora,  Eucera  and  Saropoda  (including,  however,  only  seven 

1  It  is  impossible  for  us  here  to  deal  with  the  question  of  the  origin  of  tin-  para- 
sitic habit  in  bees.  The  reader  wishing  for  information  as  to  this  may  refer  to 
Prof.  Perez's  paper,  Act.  Sue.  Bordeaux,  xlvii.  1895.  p.  300. 


i  SCOPULIPEDES CARPENTER-BEES  33 

species),  are  referred  to  the  Scopulipedes  ;  in  some  forms  a  con- 
siderable resemblance  to  the  Bonibi  is  exhibited,  indeed  the 
female  of  one  of  our  species  of  Anthopkora  is  so  very  like  the 
worker  of  Uomlns  hortorum  var.  harrisellus,  that  it  would  puzzle 
any  one  to  distinguish  them  by  a  superficial  inspection,  the 
colour  of  the  hair  on  the  hind  legs  being  the  only  obvious  differ- 
ence. Anthophora  is  one  of  the  most  extensive  and  widely 
distributed  of  the  genera  of  bees.  Some  of  the  species  make 
burrows  in  cliffs  and  form  large  colonies  which  are  continued  for 
many  years  in  the  same  locality.  Friese  has  published  many 
details  of  the  industry  and  metamorphoses  of  some  of  the  species 
of  this  genus  ;  the  most  remarkable  point  he  has  discovered  being 
that  A.  per  sonata  at  Strasburg  takes  two  years  to  accomplish  the 
life-cycle  of  one  generation.  Some  of  the  European  species  of  the 
genus  have  been  found  to  be  very  subject  to  the  attacks  of  para- 
sites. An  anomalous  beetle,  Sitaris,  has  been  found  in  the  nests 
of  A.  pilipes ;  and  this  same  Anthophora  is  also  parasitised  by 
another  beetle,  Meloe,  as  well  as  by  a  bee  of  the  genus  Melecta. 

The  genus  Xylocopa  l  contains  many  of  the  largest  and  most 
powerful  of  the  bees,  and  is  very  widely  distributed  over  the 
earth.  In  Europe  only  four  or  five  species  have  been  found,  and 
none  of  them  extend  far  northwards,  X.  riolacea  being  the  only 
one  that  comes  so  far  as  Paris.  They  are  usually  black  or  blue- 
black  in  colour,  of  broad,  robust  build,  with  shining  integuments 
more  or  less  covered  with  hair.  X.  molacea  is  known  as  the 
carpenter-bee  from  its  habit  of  working  in  dry  wood  ;  it  does  not 
touch  living  timber,  but  will  form  its  nest  in  all  sorts  of  dried 
wood.  It  makes  a  cylindrical  hole,  and  this  gives  access  to  three 
or  four  parallel  galleries  in  which  the  broad  cells  are  placed ;  the 
cells  are  always  isolated  by  a  partition  ;  the  bee  forms  this  by 
cementing  together  with  the  products  of  its  salivary  glands  the 
fragments  of  wood  it  cuts  out.  Its  habits  have  been  described 
at  length  by  Reaumur,  who  alludes  to  it  under  the  name  of 
"  abeille  perce-bois."  This  bee  hibernates  in  the  imago  condition, 
both  sexes  reappearing  in  the  spring.  Possibly  there  is  more  than 
one  generation  in  the  year,  as  Reaumur  states  that  specimens 
that  were  tiny  larvae  on  the  12th  of  June  had  by  the  2nd  of  July 
consumed  all  their  stock  of  provisions  ;  they  then  fasted  for  a  few 
days,  and  on  the  7th  or  8th  of  July  became  pupae,  and  in  the  first 

1  Refer  to  p.  70  iwstea,  note,  as  to  a  recent  discovery  about  Xylocopa. 
VOL.  VI  D 


34 


HYMENOPTERA 


CHAP. 


days  of  August  were  ready  to  emerge  as  perfect  Insects.  Thus 
the  whole  cycle  of  metamorphoses  is  passed  through  in  about 
eight  weeks.  This  species,  though  very  clever  in  drilling  holes, 
does  not  hesitate  to  appropriate  old  burrows  should  they  be  at 
hand.  Fabre  observed  that  it  was  also  quite  willing  to  save 
itself  labour  by  forming  its  cells  in  hollow  reeds  of  sufficient 
calibre.  AVe  have  figured  the  larva,  and  pupa  of  this  species  in 
the  previous  volume  (p.  170). 

Xylocopa  chloroptera  in  E.  India  selects  a  hollow  bamboo  for 
its  nidus ;   it  cements  together  the  pieces  obtained  in  clearing 


FIG.  17. — Xylocopa  (Koptorthosoma),  $2).  uear.//<nv)///V//r.*ceHs,  <J.     Sarawak. 

out  the  bamboo,  and  uses  them  as  horizontal  partitions  to  separate 
the  tube  into  cells.  The  species  is  much  infested  with  a  small 
Chalcid  of  the  genus  £/u-//rtus :  300  specimens  of  the  parasite 
have  been  reared  from  a  single  larva  of  the  bee ;  two-thirds  of 
the  larvae  of  this  bee  that  Home  endeavoured  to  rear  were 
destroyed  by  the  little  Chalcid. 

The  most  beautiful  and  remarkable  of  all  the  bees  are 
the  species  of  Euglossa.  This  genus  is  peculiar  to  Tropical 
America,  and  derives  its  name  from  the  great  length  of  the 
proboscis,  which  in  some  species  surpasses  that  of  the  body.  The 
colours  in  Et/ylossa  proper  are  violet,  purple,  golden,  and  metallic 
green,  and  two  of  these  are  frequently  combined  in  the  most  har- 
monious manner:  the  hind  tibia  is  greatly  developed  and  forms 
a  plate,  the  outer  surface  of  which  is  highly  polished,  while  the 
margins  are  furnished  with  rigid  hairs.  Very  little  is  known  as 
to  the  habits  of  these  bees;  they  were  formerly  supposed  to  be 


DASYGASTRES MASON-BEES 


35 


a 


f 


social ;  but  this  is  doubtful,  Bates  having  recorded  that  E.  sur- 
inamensis  forms  a  "  solitary  nest."  Lucas  concluded  that  E. 
cordata  is  social,  011  the  authority  of  a  nest  containing 
dozen  individuals."  No  workers 
are  known.  The  species  of 
Eulema  have  a  shorter  tongue 
than  Euglossa,  and  in  form 
and  colour  a  good  deal  re- 
semble our  species  of  Bonibus 
and  Apathus. 

The  group  DASYGASTRES  in- 
cludes seven  European  genera, 
four  being  British  (Ghelostoma 
being  included  in  Heriacles). 
The  ventral  surface  of  the  hind 
body  is  densely  set  in  the 
females  with  regularly  arranged 
hairs,  by  means  of  which  the 
pollen  is  carried.  In  many  of 
the  Dasygastres  (Megacliile, 
e.g.}  the  labrum  is  very  large, 
and  in  repose  is  inflected  on 
to  the  lower  side  of  the  head, 
and  closely  applied  to  the 
doubled -in  tongue,  which  it  - 

FIG.  18.  —  Euglossa  cordata,    &.     Amazons. 
Serves     to     protect  ;     the     man-          A,  The  Insect  with  extended  proboscis  ; 

dibles  then  lock  together  out- 
side the  labrum,  which  is  thus  completely  concealed.      This  group 
includes  some  of  the  most  interesting  of  the  solitary  bees. 

The  genus  Clicdicodoma  is  not  found  in  our  own  country,  but 
in  the  South  of  France  there  exist  three  or  four  species.  Their 
habits  have  given  rise  to  much  discussion,  having  been  described 
by  various  naturalists,  among  whom  are  included  Reaumur  and 
Fabre.  These  Insects  are  called  mason-bees,  and  construct  nests  of 
very  solid  masonry.  C.  muraria  is  in  appearance  somewhat  inter- 
mediate between  a  honey-bee  and  a  JSomb-us ;  it  is  densely  hairy, 
and  the  sexes  are  very  different  in  colour.  It  is  solitary  in  its 
habits,  and  usually  chooses  a  large  stone  as  a  solid  basis  for  its 
habitation.  On  this  a  cell  is  formed,  the  material  used  being 
a  kind  of  cement  made  by  the  Insect  from  the  mixture  of  a 


HYMENOPTERA 


CHAP. 


suitable  sort  of  earth  with  the  material  secreted  by  its  own 
salivary  glands  ;  the  amount  of  cement  used  is  reduced  1  >y  the 
artifice  of  building  small  stones  into  the  walls  of  the  cell ;  the 
stones  are  selected  with  great  care.  When  a  cell  about  an  inch 

in  depth  has  been  formed  in 
this  manner,  the  bee  commences 
to  fill  it  with  food,  consisting 
of  honey  and  pollen ;  a  little 
honey  is  brought  and  is  dis- 
charged into  the  cell,  then  some 
pollen  is  added.  This  bee,  like 
other  Dasygastres,  carries  the 
pollen  by  means  of  hairs  on 
the  under  surface  of  the  body  ; 
to  place  this  pollen  in  the  cell 
the  Insect  therefore  enters  back- 
wards, and  then  with  the  pair 
of  hind  legs  brushes  and  scrapes 
the  under  surface  of  the  body 
so  as  to  make  the  pollen  fall  off 
into  the  cell ;  it  then  starts  for 
Greece,  a  fresh  cargo ;  after  a  few  loads 
have  been  placed  in  the  recep- 
tacle, the  Insect  mixes  the  honey  and  pollen  into  a  paste 
with  the  mandibles,  and  again  continues  its  foraging  until  it 
has  about  half  filled  the  cell ;  then  an  egg  is  laid,  and  the 
apartment  is  at  once  closed  with  cement.  This  work  is  all 
accomplished,  if  the  weather  be  favourable,  in  about  two  clays, 
after  which  the  Insect  commences  the  formation  of  a  second 
cell,  joined  to  the  first,  and  so  on  till  eight  or  nine  of  these 
receptacles  have  been  constructed  ;  then  comes  the  final  operation 
of  adding  an  additional  protection  in  the  shape  of  a  thick  layer  of 
mortar  placed  over  the  whole  ;  the  construction,  when  thus  com- 
pleted, forms  a  sort  of  dome  of  cement  about  the  size  of  half  an 
orange.  In  this  receptacle  the  larvae  pass  many  months,  exposed 
to  the  extreme  heat  of  summer  as  well  as  to  the  cold  of  winter. 
The  larvae,  however,  are  exposed  to  numerous  other  perils  ;  and  we 
have  already  related  (vol.  v,  p.  540)  how  Lfitcospis  gigas  succeeds 
in  perforating  the  masonry  and  depositing  therein  an  egg,  so  that 
a  Leucospis  is  reared  in  the  cell  instead  of  a  Chalicodoma. 


FlG.  19. — ChalicoiliniKi   ninri>riii. 
A,  Male  ;  B,  female. 


i  DASYGASTRES — MASON-BEES  37 

This  Insect  has  been  the  object  of  some  of  J.  H.  Fabre's 
most  instructive  studies  on  instinct.1  Although  it  is  impossible 
for  us  here  to  consider  in  a  thorough  manner  the  various  points 
he  has  discussed,  yet  some  of  them  are  of  such  interest  and  im- 
portance as  to  demand  something  more  than  a  passing  allusion. 

We  have  mentioned  that  the  nest  of  Clialicodoma  is  roofed 
with  a  layer  of  solid  cement  in  addition  to  the  first  covering 
with  which  the  bee  seals  up  each  cell.  When  the  metamorphoses 
of  the  imprisoned  larva  have  been  passed  through,  and  the  moment 
for  its  emergence  as  a  perfect  Insect  has  arrived,  the  prisoner  has 
to  make  its  way  through  the  solid  wall  by  which  it  is  encom- 
passed. Usually  it  finds  no  difficulty  in  accomplishing  the  task 
of  breaking  through  the  roof,  so  that  the  powers  of  its  mandibles 
must  be  very  great.  Reaumur  has,  however,  recorded  that  a  nest 
of  this  mason-bee  was  placed  under  a  glass  funnel,  the  orifice  of 
which  was  covered  with  gauze,  and  that  the  Insects  when  they 
emerged  from  the  nest  were  unable  to  make  their  way  through 
the  gauze,  and  consequently  perished  under  the  glass  cover ;  and 
he  concluded  that  such  insects  are  only  able  to  accomplish  the 
tasks  that  naturally  fall  to  their  lot.  By  some  fresh  experiments 
Fabre,  however,  has  put  the  facts  in  a  different  light.  He 
remarks  that  when  the  Insects  have,  in  the  ordinary  course  of 
emergence,  perforated  the  walls  of  their  dark  prison,  they  find 
themselves  in  the  daylight,  and  at  liberty  to  walk  a\vay ;  when 
they  have  made  their  escape  from  a  nest  placed  under  a  glass 
cover,  they,  having  no  knowledge  of  glass,  find  themselves  in 
daylight  and  imprisoned  by  the  glass,  which,  to  their  inexperience, 
does  not  appear  to  be  an  obstacle,  and  they  therefore,  he  thought, 
might  perhaps  exhaust  themselves  in  vain  efforts  to  pass  through 
this  invisible  obstacle.  He  therefore  took  some  cocoons  contain- 
ing pupae  from  a  nest,  placed  each  one  of  them  in  a  tube  of  reed, 
and  stopped  the  ends  of  the  reeds  with  various  substances,  in 
one  case  earth,  in  another  pith,  in  a  third  brown  paper  ;  the 
reeds  were  then  so  arranged  that  the  Insects  in  them  were  in  a 
natural  position  ;  in  due  course  all  the  Insects  emerged,  none  of 
them  apparently  having  found  the  novel  nature  of  the  obstacle  a 
serious  impediment.  Some  complete  nests  were  then  taken  with 
their  inmates,  and  to  the  exterior  of  one  of  them  a  sheet  of 
opaque  paper  was  closely  fastened,  while  to  another  the  same 

1  Souvenirs  entomoloyiqucs.     4  vols.  Paris,  1879  to  1891. 


38  HYMENOPTERA  CHAP. 

sort  of  paper  was  applied  in  the  form  of  a  dome,  leaving  thus  a 
considerable  space  between  the  true  cover  of  the  nest  and  the 
covering  of  paper.  From  the  first  nest  the  Insects  made  their 
escape  in  the  usual  manner,  thus  again  proving  that  paper  can 
be  easily  pierced  by  them.  From  the  second  nest  they  also 
liberated  themselves,  but  failed  to  make  their  way  out  through 
the  dome  of  paper,  and  perished  beneath  it ;  thus  showing  that 
paper  added  to  the  natural  wall  caused  them  no  difficulty,  but 
that  paper  separated  therefrom  by  a  space  was  an  insuperable 
obstacle.  Professor  Perez  has  pointed  out  that  this  is  no  doubt 
due  to  the  large  space  offered  to  the  bee,  which  consequently 
moves  about,  and  does  not  concentrate  its  efforts  on  a  single 
spot,  as  it  of  course  is  compelled  to  du  when  confined  in  its 
natural  cell. 

The  power  of  the  mason -bee  to  find  its  nest  again  when 
removed  to  a  distance  from  it  is  another  point  that  was  tested 
by  Du  Hamel  and  recounted  by  Reaumur.  As  regards  this 
Fabre  has  also  made  some  very  valuable  observations.  He  marked 
some  specimens  of  the  bee,  and  under  cover  removed  them  to 
a  distance  of  four  kilometres,  and  then  liberated  them ;  the 
result  proved  that  the  bees  easily  found  their  way  back  again, 
and  indeed  were  so  little  discomposed  by  the  removal  that  they 
reached  their  nests  laden  with  pollen  as  if  they  had  merely  been 
out  on  an  ordinary  journey.  On  one  of  these  occasions  he 
observed  that  a  Chalicodoma,  on  returning,  found  that  another 
bee  had  during  her  absence  taken  possession  of  her  partially 
completed  cell,  and  was  unwilling  to  relinquish  it ;  whereupon 
a  battle  between  the  two  took  place.  The  account  of  this  is 
specially  interesting,  because  it  would  appear  that  the  two  com- 
batants did  not  seek  to  injure  one  another,  but  were  merely 
eno-ag-ed  in  testing,  as  it  were,  which  was  the  more  serious  in  its 

C>     O  O> 

claims  to  the  proprietorship  of  the  cell  in  dispute.  The  matter 
ended  by  the  original  constructor  regaining  and  retaining  posses- 
sion. Fabre  says  that  in  the  case  of  Chalicodoma  it  is  quite  a 
common  thing  for  an  uncompleted  cell  to  be  thus  appropriated 
by  a  stranger  during  the  absence  of  the  rightful  owner,  and  that 
after  a  scene  of  the  kind  described  above,  the  latter  of  the  two 
claimants  ;il\\;iys  regains  possession,  thus  leading  one  to  suppose 
that  some  sense  of  rightful  ownership  exists  in  these  bees;  the 
usurper  expressing,  as  it  were,  by  its  actions  the  idea — Before  I 


i  DASYGASTRES MASON-BEES FINDING  THE  NEST         39 

resign  my  claims  I  must  require  you  to  go  through  the  exertions 
that  will  prove  you  to  be  really  the  lawful  owner. 

Another  experiment  was  made  with  forty  specimens  of  Chali- 
codoma  pyrenaica,  which  were  removed  to  a  distance  of  four 
kilometres  and  then  liberated.  About  twenty  of  the  individuals 
had  been  somewhat  injured  by  the  processes  of  capturing,  mark- 
ing, and  transferring,  and  proved  unable  to  make  a  proper  start. 
The  others  went  off  well  when  released,  and  in  forty  minutes  the 
arrivals  at  the  nest  had  already  commenced.  The  next  morning 
he  was  able  to  ascertain  that  fifteen  at  least  had  found  their  way 
back,  and  that  it  was  probable  that  most  of  the  uninjured  bees 
had  reached  home ;  and  this  although,  as  Fabre  believed,  they 
had  never  before  seen  the  spot  where  he  liberated  them. 

These  observations  on  the  power  of  Chalicodoma  to  regain 
its  nest  attracted  the  attention  of  Charles  Darwin,  who  wrote  to 
M.  Fabre,  and  suggested  that  further  observations  should  be 
made  with  the  view  of  ascertaining  by  means  of  what  sense  these 
bees  were  able  to  accomplish  their  return.  For  it  must  be  borne 
in  mind  that  this  bee  is  very  different  from  the  domestic  bee, 
inasmuch  as  it  enjoys  but  a  brief  life  in  the  winged  state,  and  it 
is  therefore  to  be  presumed  that  an  individual  has  no  knowledge 
of  such  comparatively  distant  localities  as  those  to  which  Fabre 
transported  it.  Further  observations  made  by  the  Frenchman 
have  unfortunately  failed  to  throw  any  light  on  this  point. 
Darwin  thought  it  might  possibly  be  some  sensitiveness  to 
magnetic  conditions  that  enabled  the  bees  to  return  home, 
and  suggested  that  they  should  be  tested  as  to  this.  Fabre 
accordingly  made  some  minute  magnets,  and  fixed  one  to  each 
bee  previous  to  letting  them  loose  for  a  return  journey.  This 
had  the  effect  of  completely  deranging  the  bees ;  and  it  was  there- 
fore at  first  thought  that  the  requisite  clue  was  obtained.  It 
occurred  to  the  experimenter,  however,  to  try  the  plan  of  affixing 
small  pieces  of  straw  to  the  bees  instead  of  magnets,  and  on  this 
being  done  it  was  found  that  the  little  creatures  were  just  as 
much  deranged  by  the  straws  as  they  were  by  the  magnets :  thus 
it  became  evident  that  no  good  grounds  exist  for  considering 
that  the  bees  are  guided  by  magnetic  influences. 

One  of  the  species  *   of  Chalicodoma  observed  by  Fabre  fixes 

1  The  "  ChaUcodome  des  galcts"  or  C.  "  dcs  murailles"  of  the  French  writer  ;  in 
some  places  he  speaks  of  the  species  as  being  C.  mumrin,  in  others  as  C.  parietina. 


40  HYMENOPTERA  CHAP. 

its  nests  to  the  small  boulders  brought  down  and  left  by  the 
Khone  on  the  waste  places  of  its  banks.  This  habit  afforded 
Fabre  an  opportunity  of  removing  the  nests  during  the  process 
of  construction,  and  of  observing  the  effect  this  produced  on  the 
architects.  While  a  bee  that  had  a  nest  partially  constructed 
was  absent,  he  removed  the  stone  and  the  nest  attached  to  it  from 
one  situation  to  another  near  at  hand  and  visible  from  the 
original  site.  In  a  few  minutes  the  bee  returned  and  went 
straight  to  the  spot  where  the  nest  had  been  ;  finding  its  home 
absent  it  hovered  for  a  little  while  around  the  place,  and  then 
alighted  on  the  vacated  position,  and  walked  about  thereon  in 
search  of  the  nest ;  being  after  some  time  convinced  that  this 
was  no  longer  there,  it  took  wing,  but  speedily  returned  again  to 
the  place  and  went  through  the  same  operations.  This  series  of 
manoeuvres  was  several  times  repeated,  the  return  always  being 
made  to  the  exact  spot  where  the  nest  had  been  originally  located ; 
and  although  the  bee  in  the  course  of  its  journeys  would  pass 
over  the  nest  at  a  distance  of  perhaps  only  a  few  inches,  it  did 
not  recognise  the  object  it  was  in  search  of.  If  the  nest 
were  placed  very  near  to  the  spot  it  had  been  removed  from- 
say  at  a  distance  of  about  a  yard — it  might  happen  that  the  bee 
would  actually  come  to  the  stone  to  which  the  nest  was  fixed, 
would  visit  the  nest,  would  even  enter  into  the  cell  it  had  left 
partially  completed,  would  examine  circumspectly  the  boulder, 
but  would  always  leave  it,  and  again  return  to  the  spot  where 
the  nest  was  originally  situated,  and,  on  finding  that  the  nest 
was  not  there,  would  take  its  departure  altogether  from  the 
locality.  The  home  must  be,  for  the  bee,  in  the  proper  situation, 
or  it  is  not  recognised  as  the  desired  object.  Thus  we  are  con- 
fronted with  the  strange  fact  that  the  very  bee  that  is  able  to 
return  to  its  nest  from  a  distance  of  four  kilometres  can  no 
longer  recognise  it  when  removed  only  a  yard  from  the  original 
position.  This  extraordinary  condition  of  the  memory  of  the 
Insect  is  almost  inconceivable  by  us.  That  the  bee  should 
accurately  recognise  the  spot,  but  that  it  should  not  recognise 
the  cell  it  had  itself  just  formed  and  half-filled  with  honey-paste, 
seems  to  us  almost  incredible  ;  nevertheless,  the  fact  is  quite  con- 
sistent with  what  we  shall  subsequently  relate  in  the  case  of  the 
solitary  wasp  BeTiibex.  A  cross  experiment  was  made  by  taking 
away  the  stone  with  the  attached  nest  of  the  bee  while  the  latter 


i  DASYGASTRES MASON-BEES INSTINCT  41 

was  absent,  and  putting  in  its  place  the  nest  of  another  indi- 
vidual in  about  the  same  stage  of  construction  ;  this  nest  was 
at  once  adopted  by  the  bee,  which  indeed  was  apparently  in  no 
way  deranged  by  the  fact  that  the  edifice  was  the  work  of  another. 
A  further  experiment  was  made  by  transposing  the  positions  of 
two  nests  that  were  very  near  together,  so  that  each  bee  when 
returning  might  be  supposed  to  have  a  free  choice  as  to  which 
nest  it  would  go  to.  Unhesitatingly  each  bee  selected  the  nest 
that,  though  not  its  own,  was  in  the  position  where  its  own  had 
been.  This  series  of  experiments  seems  to  prove  that  the  Chalci- 
doma  has  very  little  sense  as  to  what  is  its  own  property,  but,  on 
the  other  hand,  has  a  most  keen  appreciation  of  locality.  As, 
however,  it  might  be  supposed  that  the  bees  were  deceived  by  the 
similarity  between  the  substituted  nests,  Fabre  transposed  two 
nests  that  were  extremely  different,  one  consisting  of  many  cells, 
the  other  of  a  single  incomplete  cell ;  it  was,  of  course,  a  necessary 
condition  of  this  experiment  that  each  of  the  two  nests,  however 
different  in  other  respects,  should  possess  one  cell  each  in  similar 
stages  of  construction ;  and  when  that  was  the  case  each  bee 
cheerfully  adopted  the  nest  that,  though  very  different  to  its 
own,  was  in  the  right  place.  This  transposition  of  nests  can  be 
rapidly  repeated,  and  thus  the  same  bee  may  be  made  to  go  on 
working  at  two  different  nests. 

Suppose,  however,  that  another  sort  of  change  be  made.  Let 
a  nest,  consisting  of  a  cell  that  is  in  an  early  stage  of  construc- 
tion, be  taken  away,  and  let  there  be  substituted  for  it  a  cell 
built  and  partially  stored  with  food.  It  might  be  supposed  that 
the  bee  would  gladly  welcome  this  change,  for  the  adoption  of 
the  substituted  cell  would  save  it  a  great  deal  of  work.  Not  so, 
however ;  the  bee  in  such  a  case  will  take  to  the  substituted  cell, 
but  will  go  on  building  at  it  although  it  is  already  of  the  full 
height,  and  will  continue  building  at  it  until  the  cell  is  made  as 
much  as  a  third  more  than  the  regulation  height.  In  fact  the 
bee,  being  in  the  building  stage  of  its  operations,  goes  on  build- 
ing, although  in  so  doing  it  is  carrying  on  a  useless,  if  not  an 
injurious,  work.  A  similar  state  ensues  when  the  Insect  ceases 
to  build  and  begins  to  bring  provisions  to  the  nest ;  although  a 
substituted  cell  may  contain  a  sufficient  store  of  food,  the  bee  goes 
on  adding  to  this,  though  it  is  wasting  its  labours  in  so  doing. 
It  should  be  noted  that  though  the  bee  must  go  through  the 


42  HYMENOPTERA  CHAP. 

appropriate  stages  of  its  labours  whether  the  result  of  so  doing 
be  beneficial  or  injurious,  yet  it  is  nevertheless  to  some  extent 
controlled  by  the  circumstances,  for  it  does  not  in  such  cases 
complete  what  should  have  been  the  full  measure  of  its  own 
individual  work  ;  it  does  not,  for  instance,  raise  the  cell  to  twice 
the  natural  height,  but  stops  building  when  the  cell  is  about 
one-third  larger  than  usual,  as  if  at  that  stage  the  absurdity  of 
the  situation  became  manifest  to  it. 

Fabre's  experiments  with  the  Chalicodoma  are  so  extremely 
instructive  as  regards  the  nature  of  instinct  in  some  of  the 
highest  Insects,  that  we  must  briefly  allude  to  some  other  of  his 
observations  even  at  the  risk  of  wearying  the  reader  who  feels 
but  little  interest  in  the  subject  of  Insect  intelligence. 

Having  discovered  that  a  mason-bee  that  was  engaged  in  the 
process  of  construction  would  go  on  building  to  an  useless  or 
even  injurious  extent,  Fabre  tried  another  experiment  to  ascer- 
tain whether  a  bee  that  was  engaged  in  the  process  of  provision- 
ing the  nest,  would  do  so  in  conditions  that  rendered  its  work 
futile.  Taking  away  a  nest  with  completely  built  cell  that  a  bee 
was  storing  with  food,  he  substituted  for  it  one  in  which  the  cell 
was  only  commenced,  and  therefore  incapable  of  containing  food  ; 
when  the  bee  with  its  store  of  provisions  reached  this  should-be 
receptacle  it  appeared  to  be  very  perplexed,  tested  the  im- 
perfect cell  with  its  antennae,  left  the  spot  and  returned  again  ; 
repeating  this  several  times  it  finally  went  to  the  cell  of 
some  stranger  to  deposit  its  treasure.  In  other  cases  the  bee 
broke  open  a  completed  cell,  and  having  done  so  went  on  bringing 
provisions  to  it;  although  it  was  already  fully  provisioned  and  an 
egg  laid  therein :  finally,  the  little  creature  having  completed 
the  bringing  of  this  superfluous  tale  of  provisions,  deposited 
a  second  egg,  and  again  sealed  up  the  cell.  But  in  no  case 
does  the  bee  go  back  from  the  provisioning  stage  to  the  build- 
ing stage  until  the  cycle  for  one  cell  of  building,  provisioning, 
and  egg-laying  is  completed :  but  when  this  is  the  case,  the 
building  of  a  fresh  cell  may  be  again  undertaken.  This  is  a 
good  example  of  the  kind  of  consecutive  necessity  that  seems 
to  be  one  of  the  chief  features  of  the  instinct  of  these  industrious 
little  animals.  Another  equally  striking  illustration  of  these 
peculiarities  of  instinct  is  offered  by  interfering  with  the  act  of 
putting  the  provisions  into  the  cell.  It  will  be  recollected  that 


i  DASYGASTRES- — MASON-BEES — PARASITES  43 

when  the  bee  brings  provisions  to  add  to  the  stock,  it  carries 
both  honey  and  pollen  ;  in  order  to  deliver  these  it  begins  by 
entering  head  first  into  the  cell  and  disgorging  the  honey,  then 
emerging  it  turns  round,  enters  backwards  and  scrapes  off  the 
pollen  from  its  body.  If  after  the  honey  has  been  discharged, 
the  bee  be  interfered  with  and  gently  removed  to  a  slight  dis- 
tance with  a  straw,  it  returns  to  complete  its  task,  but  instead  of 
going  on  with  the  actions  at  the  point  at  which  the  interruption 
took  place,  it  begins  the  series  over  again,  going  in — at  any  rate 
partially — head  first,  although  it  has  no  honey  to  discharge,  and 
having  performed  this  useless  ceremony  it  then  emerges,  turns 
round  and  adds  the  pollen.  This  illustration  is  in  some  respects 
the  reverse  of  what  might  have  been  expected,  for  the  Insect 
here  does  not  continue  the  act  at  the  interrupted  point,  but  begins 
the  series  of  actions  afresh. 

It  would  be  reasonable  to  suppose  that  an  Insect  that  takes 
the  pains  to  provide  for  the  safety  of  its  progeny  by  constructing 
a  complex  edifice  of  cement,  secures  thereby  the  advantage  of 
protection  for  its  young.  But  this  is  far  from  being  the  case. 
Notwithstanding  the  cement  and  the  thick  dome  of  mortar,  the 
Chalicodoma  is  extremely  subject  to  the  attacks  of  parasites. 
The  work  performed  by  the  creature  in  constructing  its  mass  of 
masonry  is  truly  astounding ;  Fabre  calculated  from  measure- 
ments he  made  that  for  the  construction  and  provisioning  of  a 
single  cell,  the  goings  and  comings  of  the  bee  amounted  to  15 
kilometres,  and  it  makes  for  each  nest  sometimes  as  many  as 
fifteen  cells.  Notwithstanding  all  this  labour,  it  would  appear 
that  no  real  safety  for  the  larvae  is  obtained  by  the  work.  Some 
sixteen — possibly  more — other  species  of  Insects  get  their  living 
off  this  industrious  creature.  Another  bee,  Stelis  nasuta,  breaks 
open  the  cells  after  they  have  been  completely  closed  and  places 
its  o\vn  eggs  in  them,  and  then  again  closes  the  cells  with 
mortar.  The  larvae  of  this  Stelis  develop  more  rapidly  than  do 
those  of  the  Chalicodoma,  so  that  the  result  of  this  shameless 
proceeding  is  that  the  young  one  of  the  legitimate  proprietor— 
as  we  human  beings  think  it — is  starved  to  death,  or  is  possibly 
eaten  up  as  a  dessert  by  the  Stelis  larvae,  after  they  have 
appropriated  all  the  pudding. 

Another  bee,  Dioxys  cincta,  is  even   more   audacious ;  it  flies 
about    in    a    careless  manner    among    the   Chalicodoma   at   their 


44  HYMENOPTERA  CHAP. 

work,  and  they  do  not  seem  to  object  to  its  presence  unless  it 
interferes  with  them  in  too  unmannerly  a  fashion,  when  they 
brush  it  aside.  The  Dioxys,  when  the  proprietor  leaves  the  cell, 
will  enter  it  and  taste  the  contents  ;  after  having  taken  a  few 
mouthfuls  the  impudent  creature  then  deposits  an  egg  in  the 
cell,  and,  it  is  pretty  certain,  places  it  at  or  near  the  bottom  of 
the  mass  of  pollen,  so  that  it  is  not  conspicuously  evident  to  the 
Chalicodoma  when  the  bee  again  returns  to  add  to  or  complete 
the  stock  of  provisions.  Afterwards  the  constructor  deposits  its 
own  egg  in  the  cell  and  closes  it.  The  final  result  is  much  the 
same  as  in  the  case  of  the  Stelis,  that  is  to  say,  the  Chalicodoma 
has  provided  food  for  an  usurper  ;  but  it  appears  probable  that 
the  consummation  is  reached  in  a  somewhat  different  manner, 
namely,  by  the  Dioxi/s  larva  eating  the  egg  of  the  Chali- 
codoma, instead  of  slaughtering  the  larva.  Two  of  the  Hymenop- 
tera  Parasitica  are  very  destructive  to  the  Chalicodoma,  viz. 
Leiicospis gigas  and  Mo nodontomcrus  nitidus ;  the  habits  of  which 
-ve  have  already  discussed  (vol.  v.  p.  54:!)  under  Chalcididae. 
Lainpert  has  given  a  list  of  the  Insects  attacking  the  mason-bee 
or  found  in  its  nests ;  altogether  it  would  appear  that  about 
sixteen  species  have  been  recognised,  most  of  which  destroy  the 
bee  larva,  though  some  possibly  destroy  tlje  bee's  destroyers,  and 
two  or  three  perhaps  merely  devour  dead  examples  of  the  bee,  or 
take  the  food  from  cells,  the  inhabitants  of  which  have  been 
destroyed  by  some  untoward  event.  This  author  thinks  that 
one  half  of  the  bees'  progeny  are  made  away  with  by  these 
destroyers,  while  Fabre  places  the  destruction  in  the  South  of 
France  at  a  still  higher  ratio,  telling  us  that  in  one  nest  of  nine 
cells,  the  inhabitants  of  three  were  destroyed  by  the  Dipterous 
Insect,  Anthrax  trifasciata,  of  two  by  Leucospis,  of  two  by  Stelis,  and 
of  one  by  the  smaller  Chalcid  ;  there  being  thus  only  a  single 
example  of  the  bee  that  had  not  succumbed  to  one  or  other  of 
the  enemies.  He  has  sometimes  examined  a  large  number  of 
nests  without  finding  a  single  one  that  had  not  been  attacked  by 
one  or  other  of  the  parasites,  and  more  often  than  not  several  of 
the  marauders  had  attacked  the  nest. 

It  is  said  by  Lampert  and  others  that  there  is  a  passage  in 
Pliny  relating  to  one  of  the  mason-bees,  that  the  Roman  author 
had  noticed  in  the  act  of  carrying  off  stones  to  build  into  its 
nest ;  being  unacquainted  with  the  special  habits  of  the  bee,  he 


DASYGASTRES CARDER-BEE 


45 


seems  to  have  supposed  that  the  insect  was  carrying  the  stone 
as  ballast  to  keep  itself  from  being  blown  away. 

The  bees  of  the  genus  Anthidium  are  known  to  possess  the 
habit   of  making  nests  of  wool  or  cotton,  that  they  obtain  from 
plants  growing  at  hand.      We 
have  one  species  of  this  genus 
of   bees  in   Britain ;    it   some- 
times may  be  seen  at  work  in 
the   grounds   of   our    Museum 
at    Cambridge :   it    is    referred 
to    by    Gilbert    White,     who 
says     of    it,    in    his    History 
of  Selborne :  "  There  is  a  sort 
of  wild    bee    frequenting    the 
garden-campion   for    the   sake 
of  its  tomentum,  which   prob- 
ably it  turns  to   some  purpose 
in  the  business  of  nidincation. 
It  is  very  pleasant  to  see  with 
what  address  it   strips  off  the 
pubes,   running    from   the  top 
to   the    bottom    of    a    branch, 
and  shaving  it  bare  with  the 
dexterity    of    a    hoop -shaver. 
When   it    has    got    a    bundle, 
almost  as  large  as  itself,  it  flies 
away,  holding    it    secure    between    its    chin    and    its    fore   legs." 
The  species  of   this    genus    are    remarkable    as    forming    a    con- 
spicuous   exception    to    the    rule    that    in    bees    the    female    is 
larger  than   the  male.      The   species   of  Anthidium  do   not  form 
burrows  for    themselves,  but   either   take   advantage   of  suitable 
cavities  formed  by  other   Insects  in  wood,  or  take  possession  of 
deserted   nests  of  other  bees   or    even   empty   snail-shells.      The 
workers  in  cotton,  of  which  our  British  species  A.  manic atum  is 
one,    line   the   selected    receptacle   with    a    beautiful   network   of 
cotton  or  wool,  and  inside  this  place  a  finer  layer  of  the  material, 
to  which  is  added  some  sort  of  cement  that  prevents  the  honied 
mass  stored  by  the  bees  in  this  receptacle  from  passing  out  of  it. 
A.  diadema,  one  of  the   species  that  form  nests  in  hollow  steins, 
has  been  specially  observed  by  Fabre ;  it  will  take  the  cotton  for 


FIG.  20. — Anthidium  manicatum,  Carder- 
bee.     A,  Male  ;  B,  female. 


46  IIYMENOPTERA  CHAP. 

its  work  from  any  suitable  plant  growing  near  its  nest,  and  does  not 
confine  itself  to  any  particular  natural  order  of  plants,  or  even  to 
those  that  are  indigenous  to  the  South  of  France.  When  it  has 
brought  a  ball  of  cotton  to  the  nest,  the  bee  spreads  out  and 
arranges  the  material  with  its  front  legs  and  mandibles,  and 
presses  it  down  with  its  forehead  on  to  the  cotton  previously 
deposited ;  in  this  way  a  tube  of  cotton  is  constructed  inside  the 
reed  ;  when  withdrawn,  the  tube  proved  to  be  composed  of  about 
ten  distinct  cells  arranged  in  linear  fashion,  and  connected  firmly 
together  by  means  of  the  outer  layer  of  cotton ;  the  transverse 
divisions  between  the  chambers  are  also  formed  of  cotton,  and 
each  chamber  is  stored  with  a  mixture  of  honey  and  pollen. 
The  series  of  chambers  does  not  extend  quite  to  the  end  of  the 
reed,  and  in  the  unoccupied  space  the  Insect  accumulates  small 
stones,  little  pieces  of  earth,  fragments  of  wood  or  other  similar 
small  objects,  so  as  to  form  a  sort  of  barricade  in  the  vestibule, 
and  then  closes  the  tube  by  a  barrier  of  coarser  cotton  taken 
frequently  from  some  other  plant,  the  mullein  by  preference. 
This  barricade  would  appear  to  be  an  ingenious  attempt  to  keep 
out  parasites,  but  if  so,  it  is  a  failure,  at  any  rate  as  against 
Leticospis,  which  insinuates  its  eggs  through  the  sides,  and 
frequently  destroys  to  the  last  one  the  inhabitants  of  the 
fortress.  Fabre  states  that  these  Anthidium.,  as  well  as  J\fcf/»cJ/ i/c, 
will  continue  to  construct  cells  when  they  have  no  eggs  to  place 
in  them  ;  in  such  a  case  it  would  appear  from  his  remarks  that 
the  cells  are  made  in  due  form  and  the  extremity  of  the  reed 
closed,  but  no  provisions  are  stored  in  the  chambers. 

The  larva  of  the  Anthidium  forms  a  most  singular  cocoon. 
We  have  already  noticed  the  difficulty  that  arises,  in  the  case 
of  these  Hymenopterous  larvae  shut  up  in  small  chambers,  as 
to  the  disposal  of  the  matters  resulting  from  the  incomplete 
assimilation  of  the  aliment  ingested.  To  allow  the  once-used 
food  to  mingle  with  that  still  remaining  unconsumed  would  be 
not  only  disagreeable  but  possibly  fatal  to  the  life  of  the  larva. 
Hence  some  species  retain  the  whole  of  the  excrement  until 
the  food  is  entirely  consumed,  it  being,  according  to  Adlerz,  stored 
in  a  special  pouch  at  the  end  of  the  stomach  ;  other  Hymen- 
optera,  amongst  which  we  may  mention  the  species  of  Osmici, 
place  the  excreta  in  a  vacant  space.  The  Anthidium  adopts, 
however,  a  most  remarkable  system:  about  the  middle  of  its 


i  DASYGASTRES ANTHIDIUM  47 

larval  life  it  commences  the  expulsion  of  "  frass  "  in  the  shape  of 
small  pellets,  which  it  fastens  together  with  silk,  as  the}7  are 
voided,  and  suspends  round  the  walls  of  the  chamber.  This 
curious  arrangement  not  only  results  in  keeping  the  embarrassing 
material  from  contact  with  the  food  and  with  the  larva  itself, 
but  serves,  when  the  growth  of  the  latter  is  accomplished,  as  the 
outline  or  foundations  of  the  cocoon  in  which  the  metamorphosis 
is  completed.  This  cocoon  is  of  a  very  elaborate  character ;  it 
has,  so  says  Fabre,  a  beautiful  appearance,  and  is  provided  with 
a  very  peculiar  structure  in  the  form  of  a  small  conical  pro- 
tuberance at  one  extremity  pierced  by  a  canal.  This  canal  is 
formed  with  great  care  by  the  larva,  which  from  time  to  time 
places  its  head  in  the  orifice  in  process  of  construction,  and 
stretches  the  calibre  by  opening  the  mandibles.  The  object  of 
this  peculiarity  in  the  fabrication  of  the  elaborate  cocoon  is  not 
clear,  but  Fabre  inclines  to  the  opinion  that  it  is  for  respiratory 
purposes. 

Other  species  of  this  genus  use  resin  in  place  of  cotton  as  their 
working  material.  Among  these  are  Anthidium  septemdentatum  and 
A.  bcllicosum.  The  former  species  chooses  an  old  snail-shell  as  its 
nidus,  and  constructs  in  it  near  the  top  a  barrier  of  resin,  so  as  to 
shut  off  the  part  where  the  whorl  is  too  small ;  then  beneath  the 
shelter  of  this  barrier  it  accumulates  a  store  of  honey-pollen,  de- 
posits an  egg,  and  completes  the  cell  by  another  transverse  barrier  of 
resin  ;  two  such  cells  are  usually  constructed  in  one  snail-shell,  and 
below  them  is  placed  a  barricade  of  small  miscellaneous  articles, 
similar  to  what  we  have  described  in  speaking  of  the  cotton- 
working  species  of  the  genus.  This  bee  completes  its  metamor- 
phosis, and  is  ready  to  leave  the  cell  in  early  spring.  Its  con- 
gener, A.  liellicosum,  has  the  same  habits,  with  the  exception 
that  it  works  later  in  the  year,  and  is  thus  exposed  to  a  great 
danger,  that  very  frequently  proves  fatal  to  it.  This  bee  does 
not  completely  occupy  the  snail- shell  with  its  cells,  but  leaves 
the  lower  and  larger  portion  of  the  shell  vacant.  Now,  there,  is 
another  bee,  a  species  of  Osmia,  that  is  also  fond  of  snail-shells 
as  a  nesting-place,  and  that  affects  the  same  localities  as  the 
A.  septemdentatum;  very  often  the  Osmia  selects  for  its  nest 
the  vacant  part  of  a  shell,  the  other  part  of  which  is  occupied  by 
the  Anthidium  ;  the  result  of  this  is  that  when  the  metamorphoses 
are  completed,  the  latter  bee  is  unable  to  effect  its  escape,  and 


48 


HYMENOPTERA 


CHAP. 


thus  perishes  in  the  cell.  Fabre  further  states  with  regard  to 
these  interesting  bees,  that  no  structural  differences  of  the  feet 
or  mandibles  can  be  detected  between  the  workers  in  cotton  and 
the  workers  in  resin ;  and  he  also  says  that  in  the  case  where 
two  cells  are  constructed  in  one  snail-shell,  a  male  individual  is 
produced  from  the  cell  of  the  greater  capacity,  and  a  female  from 
the  other. 

Osmia  is  one  of  the  most  important  of  the  genera  of  bees 
found  in  Europe,  and  is  remarkable  for  the  diversity  of  instinct 
displayed  in  the  formation  of  the  nests  of  the  various  species. 
As  a  rule  they  avail  themselves  for  nidification  of  hollow 
places  already  existing ;  choosing  excavations  in  wood,  in  the 

mortar  of  walls,  and  even  in 
sandbanks ;  in  several  cases 
the  same  species  is  found  to 
be  able  to  adapt  itself  to 
more  than  one  kind  of  these 
very  different  substances.  This 
variety  of  habit  will  render 
it  impossible  for  us  to  do 
justice  to  this  interesting 
genus  within  the  space  at 


FIG.  21. — Osmia  tricornis,  ?.     Algeria. 


our  disposal,  and  we  must 
content  ourselves  with  a  con- 
sideration of  one  or  two  of  the  more  instructive  of  the  traits 
of  Ositiia  life.  0.  tridentata  forms  its  nest  in  the  steins  of 
brambles,  of  which  it  excavates  the  pith  ;  its  mode  of  working 
and  some  other  details  of  its  life  have  been  well  depicted  by 
Fabre.  The  Insect  having  selected  a  suitable  bramble-stalk  with 
a  cut  extremity,  forms  a  cylindrical  burrow  in  the  pith  thereof, 
extending  the  tunnel  as  far  as  will  be  required  to  allow  the 
construction  of  ten  or  more  "cells  placed  one  after  the  other  in 
the  axis  of  the  cylinder ;  the  bee  does  not  at  first  clear  out  quite 
all  the  pith,  but  merely  forms  a  tunnel  through  it,  and  then 
commences  the  construction  of  the  first  cell,  which  is  placed  at 
the  end  of  the  tunnel  that  is  most  remote  from  the  entrance. 
This  cavity  is  to  be  of  oval  form,  and  the  Insect  therefore  cuts 
away  more  of  the  pith  so  as  to  make  an  oval  space,  but  somewhat 
truncate,  as  it  were,  at  each  end,  the  plane  of  truncation  at  the 
proximal  extremity  being  of  course  an  orifice.  The  first  cell 


i  DASYGASTRES OSMIA  49 

thus  made  is  stored  with  pollen  and  honey,  and  an  egg  is 
deposited.  Then  a  barrier  has  to  lie  constructed  to  close  this 
chamber ;  the  material  used  for  the  barrier  is  the  pith  of  the 
stem,  and  the  Insect  cuts  the  material  required  for  the  purpose 
from  the  walls  of  the  second  chamber ;  the  excavation  of  the 
second  chamber  is,  in  fact,  made  to  furnish  the  material  for  clos- 
ing up  the  first  cell.  In  this  way  a  chain  of  cells  is  constructed, 
their  number  being  sometimes  as  many  as  fifteen.  The  mode 
in  which  the  bees,  when  the  transformations  of  the  larvae  and 
pupae  have  been  completed,  escape  from  the  chain  of  cells,  has 
been  the  subject  of  much  discussion,  and  errors  have  arisen  from 
inference  being  allowed  to  take  the  place  of  observation.  Thus 
Dufour,  who  noted  this  same  mode  of  construction  and  arrange- 
ment in  another  Hymenopteron  (Odyncrus  nidulator},  perceived 
that  there  was  only  one  orifice  of  exit,  and  also  that  the  Insect 
that  was  placed  at  the  greatest  distance  from  this  was  the 
one  that,  being  the  oldest  of  the  series,  might  be  expected  to 
be  the  first  ready  to  emerge  ;  and  as  the  other  cocoons  would 
necessarily  be  in  the  way  of  its  getting  out,  he  concluded  that 
the  egg  that  \vas  last  laid  produced  the  first  Insect  ready  for 
emergence.  Fabre  tested  this  by  some  ingenious  experiments, 
and  found  that  this  was  not  the  case,  but  that  the  Insects  became 
ready  to  leave  their  place  of  imprisonment  without  any  reference 
to  the  order  in  which  the  eggs  were  laid,  and  he  further  noticed 
some  very  curious  facts  with  reference  to  the  mode  of  emergence 
of  Osmia  tridentata.  Each  Insect,  when  it  desires  to  leave  the 
bramble  stem,  tears  open  the  cocoon  in  which  it  is  enclosed,  and  also 
bites  through  the  barrier  placed  by  the  mother  between  it  and 
the  Insect  that  is  next  it,  and  that  separates  it  from  the  orifice 
of  exit.  Of  course,  if  it  happen  to  be  the  outside  one  of  the 
series  it  can  then  escape  at  once  ;  but  if  it  should  lie  one  farther 
down  in  the  Indian  file  it  will  not  touch  the  cocoon  beyond,  but 
waits  patiently,  possibly  for  days  ;  if  it  then  still  find  itself  con- 
fined it  endeavours  to  escape  by  squeezing  past  the  cocoon  that 
intervenes  between  it  and  liberty,  and  by  biting  away  the  material 
at  the  sides  so  as  to  enlarge  the  passage ;  it  may  succeed  in  doing 
this,  and  so  get  out,  but  if  it  fail  to  make  a  side  passage  it  will 
not  touch  the  cocoons  that  are  in  its  way.  In  the  ordinary 
course  of  events,  supposing  all  to  go  well  with  the  family,  all 
the  cocoons  produce  their  inmates  in  a  state  for  emergence  within 

VOL.   VI  E 


50  HYMENOPTERA  CHAP. 

a  week  or  two,  and  so  all  get  out.  Frequently,  however,  the 
emergence  is  prevented  by  something  having  gone  wrong  with 
one  of  the  outer  Insects,  in  which  case  all  beyond  it  perish  unless 
they  are  strong  enough  to  bite  a  hole  through  the  sides  of  the 
bramble-stem.  Thus  it  appears  that  whether  a  particular  Osmia 
shall  be  able  to  emerge  or  not  depends  on  two  things — (1)  whether 
all  goes  well  with  all  the  other  Insects  between  it  and  the  orifice, 
and  (2)  whether  the  Insect  can  bite  a  lateral  hole  or  not;  this 
latter  point  also  largely  depends  on  the  thickness  of  the  outer 
part  of  the  stem  of  the  bramble.  Fabre's  experiments  on 
these  points  have  been  repeated,  and  his  results  confirmed  by 
Nicolas. 

The  fact  that  an  Osmia  would  itself  perish  rather  than  attack 
the  cocoon  of  its  brother  or  sister  is  certainly  very  remarkable, 
and  it  induced  Fabre  to  make  some  further  experiments.  He 
took  some  cocoons  containing  dead  specimens  of  Osmia,  and  placed 
them  in  the  road  of  an  Osmia  ready  for  exit,  and  found  that  in 
such  case  the  bee  made  its  way  out  by  demolishing  without  any 
scruple  the  cocoons  and  dead  larvae  that  intervened  between  it 
and  liberty.  He  then  took  some  other  reeds,  and  blocked  the 
way  of  exit  with  cocoons  containing  living  larvae,  but  of  another 
species  of  Hymenoptera.  Solcnius  vagus  and  Osmia  detrita  were 
the  species  experimented  on  in  this  case,  and  he  found  that  the 
Osmia  destroyed  the  cocoon  and  living  larvae  of  the  Solenius, 
and  so  made  its  way  out.  Thus  it  appears  that  Osmia  will 
respect  the  life  of  its  own  species,  and  die  rather  than  destroy  it, 
but  has  no  similar  respect  for  the  life  of  another  species. 

Some  of  Fabre's  most  instructive  chapters  are  devoted  to  the 
habits  and  instincts  of  various  species  of  the  genus  Osmia.  It 
is  impossible  here  to  find  space  even  to  summarise  them,  still 
more  impossible  to  do  them  justice ;  but  we  have  selected  the 
history  just  recounted,  because  it  is  rare  to  find  in  the  insect 
world  instances  of  such  self-sacrifice  by  an  individual  for  one  of 
the  same  generation.  It  would  be  quite  improper  to  generalise 
from  this  case,  however,  and  conclude  that  such  respect  for  its 
own  species  is  common  even  amongst  the  Osmia.  Fabre,  indeed, 
relates  a  case  that  offers  a  sad  contrast  to  the  scene  of  self- 
sacrifice  and  respect  for  the  rights  of  others  that  we  have  roughly 
portrayed.  He  was  able  to  induce  a  colony  of  Osmia  tricornis 
(another  species  of  the  genus,  be  it  noted)  to  establish  itself  and 


i  DASYGASTRES LEAF-CUTTING  BEES  5  I 

work  in  a  series  of  glass  tubes  that  he  placed  on  a  table  in  his 
laboratory.  He  marked  various  individuals,  so  that  he  was  able 
to  recognise  them  and  note  the  progress  of  their  industrial  works. 
Quite  a  large  number  of  specimens  thus  established  themselves 
and  concluded  their  work  before  his  very  eyes.  Some  individuals, 
however,  when  they  had  completed  the  formation  of  a  series  of 
cells  in  a  glass  tube  or  in  a  reed,  had  still  not  entirely  completed 
their  tale  of  work.  It  would  be  supposed  that  in  such  a  case 
the  individual  would  commence  the  formation  of  another  series 
of  cells  in  an  unoccupied  tube.  This  was  not,  however,  the  case. 
The  bee  preferred  tearing  open  one  or  more  cells  already  completed 
—in  some  cases,  even  by  itself — scattering  the  contents,  and  de- 
vouring the  egg  ;  then  again  provisioning  the  cell,  it  would  deposit 
a  fresh  egg,  and  close  the  chamber.  These  brief  remarks  will 
perhaps  suffice  to  give  some  idea  of  the  variety  of  instinct  and 
habit  that  prevails  in  this  very  interesting  genus.  Friese  observes 
that  the  variety  of  habits  in  this  genus  is  accompanied  as  a  rule 
by  paucity  of  individuals  of  a  species,  so  that  in  central  Europe 
a  collector  must  be  prepared  to  give  some  twenty  years  or  so  of 
attention  to  the  genus  before  he  can  consider  he  has  obtained  all 
the  species  of  Osmia  that  inhabit  his  district. 

As  a  prelude  to  the  remarks  we  are  about  to  make  on  the 
leaf-cutting  bees  of  the  genus  Meyachile  it  is  well  to  state  that 
the  bee,  the  habits  of  which  were  described  by  Eeaumur  under 
the  name  of  "  1'abeille  tapissiere,"  and  that  uses  portions  of  the 
leaves  of  the  scarlet  poppy  to  line  its  nest,  is  now  assigned  to 
the  genus  Osmia,  although  Latreille,  in  the  interval  that  has 
elapsed  since  the  publication  of  Reaumur's  work,  founded  the 
genus  Antliocopa  for  the  bee  in  question.  Megacliile  is  one  of 
the  most  important  of  the  genera  of  the  Dasygastres,  being 
found  in  most  parts  of  the  world,  even  in  the  Sandwich 
Islands ;  it  consists  of  bees  averaging  about  the  size  of 
the  honey-bee  (though  some  are  considerably  larger,  others 
smaller),  and  having  the  labrum  largely  developed  ;  this  organ  is 
capable  of  complete  inflection  to  the  under  side  of  the  head,  and 
when  in  the  condition  of  repose  it  is  thus  infolded,  it  underlaps 
and  protects  the  larger  part  of  the  lower  lip  ;  the  mandibles 
close  over  the  infolded  labrum,  so  that,  when  the  Insect  is  at  rest, 
this  appears  to  be  altogether  absent.  These  bees  are  called 
leaf-cutters,  from  their  habit  of  forming  the  cells  for  their  nest 


HYMENOPTERA 


CHAP. 


out  of  pieces  of  the  leaves  of  plants.  We  have  several  species  in 
Britain  ;  they  are  very  like  the  common  honey-bee  in  general 
appearance,  though  rather  more  robustly  formed.  These  Insects, 
like  the  Osmiae,  avail  themselves  of  existing  hollow  places  as 
receptacles  in  which  to  place  their  nests.  M.  alljocincta  frequently 
takes  possession  of  a  deserted  worm-burrow  in  the  ground.  The 
burrow  being  longer  than  necessary  the  bee  commences  by  cutting 
off  the  more  distant  part  by  means  of  a  barricade  of  foliage  ;  this 
being  done,  it  proceeds  to  form  a  series  of  cells,  each  shaped  like 
a  thimble  with  a  lid  at  the  open  end  (Fig.  22,  A).  The  body  of 
the  thimble  is  formed  of  large  oval  pieces  of  leaf,  the  lid  of 
smaller  round  pieces  ;  the  fragments  are  cut  with  great  skill  from 
the  leaves  of  growing1  plants  by  the  Insect,  which  seems  to  have 
an  idea  of  the  form  and  size  of  the  piece  of  foliage  necessary  for 
each  particular  stage  of  its  work. 

Home  has  given  particulars  as  to  the  nest  of  MegacTiile  a  utltm- 
cina  (fascieulata),  an  East  Indian  species.1     The  material  employed 

was  either  the  leaves  of  the  Indian 
pulse  or  of  the  rose.  Long  pieces 
are  cut  by  the  Insect  from  the 
leaf,  and  with  these  a  cell  is  formed  ; 
a  circular  piece  is  next  cut,  and 
with  this  a  lid  is  made  for  the 
receptacle.  The  cells  are  about 
the  size  and  shape  of  a  common 
thimble  ;  in  one  specimen  that 
Home  examined  no  less  than 
thirty-two  pieces  of  leaf  disposed 
in  seven  layers  wTere  used  for  one 
cell,  in  addition  to  three  pieces  for 
the  round  top.  The  cells  are 
carefully  prepared,  and  some  kind 
of  matter  of  a  gummy  nature  is 
believed  to  be  used  to  keep  in 

FIG.    22. — Nidification    o(    leaf -cutting 

bee,  Megachile  anthracina.  A,  ..m-  place  the  pieces  forming  the  ill- 
cell  separated  with  lid  open;  the  terior  *  The  ceR  ,  d 
larva  (a)  reposing  on  the  foocl  ;  B, 

p;ut  of  a  string  of  the  cells.    (After  end  to  end,  as  shown  in  Fig.  22,  B  ; 

five   to   seven   cells   form   a    series, 
and  four  or  six  series  are  believed  to  be  constructed  by  one  pair 

1    Trims.  Zool.  ,SW.  London,  vii.  1870,  p.  178. 


i  BEES DASYGASTRES SOCIALES  5  3 

of  this  bee,  the  mass  being  located  in  a  hollow  in  masonry  or 
some  similar  position.  Each  cell  when  completed  is  half  filled 
with  pollen  in  the  usual  manner,  and  an  egg  is  then  laid  in  it. 
This  bee  is  much  infested  by  parasites,  and  is  eaten  by  the  Grey 
Hornbill  (Meniceros  Mcornis*). 

Megachile  lanata  is  one  of  the  Hymenoptera  that  in  East 
India  enter  houses  to  build  their  own  habitations.  According 
to  Home  both  sexes  take  part  in  the  work  of  construction,  and 
the  spots  chosen  are  frequently  of  a  very  odd  nature.  The 
material  used  is  some  kind  of  clay,  and  the  natural  situation 
may  be  considered  to  be  the  interior  of  a  hollow  tube,  such  as 
the  stem  of  a  bamboo  ;  but  the  barrel  of  a  gun,  and  the  hollow 
in  the  back  of  a  book  that  has  been  left  lying  open,  have  been 
occasionally  selected  by  the  Insect  as  suitable.  Smith  states 
that  the  individuals  developed  in  the  lower  part  of  a  tubular 
series  of  this  species  were  females,  "  which  sex  takes  longer  to 
develop,  and  thus  an  exit  is  not  required  for  them  so  soon  as  for 
the  occupants  of  the  upper  cells  which  are  males."  J/.  proxima,  a 
species  almost  exactly  similar  in  appearance  to  M.  lanata,  makes 
its  cells  of  leaf-cuttings,  however,  and  places  them  in  soft  soil. 

Eabre  states  that  M.  albocincta,  which  commences  the 
formation  of  its  nest  in  a  worm -burrow  by  means  of  a  barricade, 
frequently  makes  the  barricade,  but  no  nest  ;  sometimes  it  will 
indeed  make  the  barricade  more  than  twice  the  proper  size,  and 
thus  completely  fill  up  the  worm  burrow.  Fabre  considers  that 
these  eccentric  proceedings  are  due  to  individuals  that  have  already 
formed  proper  nests  elsewhere,  and  that  after  completing  these 
have  still  some  strength  remaining,  which  they  use  up  in  this 
fruitless  manner. 

The  Social  bees  (SOCIALES)  include,  so  far  as  is  yet  known, 
only  a  very  small  number  of  genera,  and  are  so  diverse,  both  in 
habits  and  structure,  that  the  propriety  of  associating  them  in 
one  group  is  more  than  doubtful ;  the  genera  are  Bomlms  (Fig. 
.'!.">1,  vol.  v.),  with  its  commensal  genus  or  section,  Ps//A///-//.s 
(Fig.  23);  Melipona  (Fig.  24),  in  which  Trigona  and  Tetragona 
may  at  present  be  included,  and  Apis  (Fig.  6) ;  this  latter  genus 
comprising  the  various  honey-bees  that  are  more  or  less  com- 
pletely domesticated  in  different  parts  of  the  world. 

In  the  genus  Boml'us  the  phenomena  connected  with  the 
social  life  are  more  similar  to  what  we  find  among  wasps 


54  HYMENOPTERA  CHAP. 

than  to  what  they  are  in  the  genus  Apis.  The  societies  come  to 
an  end  at  the  close  of  the  season,  a  few  females  live  through  the 
winter,  and  each  of  these  starts  a  new  colony  in  the  following 
spring.  Males,  females  and  workers  exist,  but  the  latter  are 
not  distinguished  by  any  good  characters  from  the  females,  and 
are,  in  fact,  nothing  but  more  or  less  imperfect  forms  thereof; 
whereas  in  Apis  the  workers  are  distinguished  by  structural 
characters  not  found  in  either  of  the  true  sexes. 

Hotter  has  given  a  description  of  the  commencement  of  a 
society  of  Bonibus  lapidarius.1  A  large  female,  at  the  end  of  May, 
collected  together  a  small  mass  of  moss,  then  made  an  expedition 
and  returned  laden  with  pollen  ;  under  cover  of  the  moss  a  cell 
was  formed  of  wax  taken  from  the  hind-body  and  mixed  with 
the  pollen  the  bee  had  brought  in ;  this  cell  was  fastened  to  a 
piece  of  wood ;  when  completed  it  formed  a  subspherical  recep- 
tacle, the  outer  wall  of  which  consisted  of  wax,  and  whose  interior 
wras  lined  with  honey-saturated  pollen  ;  then  several  eggs  were 
laid  in  this  receptacle,  and  it  was  entirely  closed.  Hotter  took 
the  completed  cell  away  to  use  it  for  museum  purposes,  and  the 
following  day  the  poor  bee  that  had  formed  it  died.  From 
observations  made  on  Bomb  us  agronun  he  was  able  to  describe 
the  subsequent  operations  ;  these  are  somewhat  as  follows  : — The 
tirst  cell  being  constructed,  stored,  and  closed,  the  industrious 
architect,  clinging  to  the  cell,  takes  a  few  days'  rest,  and  after 
this  interval  commences  the  formation  of  a  second  cell ;  this  is 
placed  by  the  side  of  the  first,  to  which  it  is  connected  by  a 
mixture  of  wax  and  pollen  ;  the  second  cell  being  completed  a 
third  may  be  formed  ;  but  the  labours  of  the  constructor  about 
this  time  are  augmented  by  the  hatching  of  the  eggs  deposited 
a  few  days  previously  ;  for  the  young  larvae,  having  soon  disposed 
of  the  small  quantity  of  food  in  the  interior  of  the  waxen  cell, 
require  feeding.  This  operation  is  carried  on  by  forming  a  small 
opening  in  the  upper  part  of  the  cell,  through  which  the  bee 
conveys  food  to  the  interior  by  ejecting  it  from  her  mouth 
through  the  hole ;  whether  the  food  is  conveyed  directly  to 
the  mouths  of  the  larvae  or  not,  Hotter  was  unable  to  observe ; 
it  being  much  more  difficult  to  approach  this  royal  founder 
without  disturbing  her  than  it  is  the  worker-bees  that  carry  on 
similar  occupations  at  a  subsequent  period  in  the  history  of  the 
1  Mt.  Ver.  Steiermark,  xxxi.  1882,  p.  69. 


SOCIALES BUMBLE-BEES  5  5 


society.  The  larvae  in  the  first  cell,  as  they  increase  in  size, 
apparently  distend  the  cell  in  an  irregular  manner,  so  that  it 
becomes  a  knobbed  and  rugged,  truffle-like  mass.  The  same 
thing  happens  with  the  other  cells  formed  by  the  queen.  Each 
of  these  larval  masses  contains,  it  should  be  noticed,  sister-larvae 
all  of  one  age ;  when  full  grown  they  pupate  in  the  mass,  and 
it  is  worthy  of  remark  that  although  all  the  eggs  in  one  larval 
mass  were  laid  at  the  same  time,  yet  the  larvae  do  not  all  pupate 
simultaneously,  neither  do  all  the  perfect  Insects  appear  at 
once,  even  if  all  are  of  one  sex.  The  pupation  takes  place 
in  a  cocoon  that  each  larva  forms  for  itself  of  excessively 
fine  silk.  The  first  broods  hatched  are  formed  chiefly,  if  not 
entirely,  of  workers,  but  small  females  may  be  produced  before 
the  end  of  the  season.  Huber  and  Schmiedeknecht  state  that 
though  the  queen  provides  the  \vorker-cells  with  food  before  the 
eggs  are  placed  therein,  yet  no  food  is  put  in  the  cells  in  which 
males  and  females  are  produced.  The  queen,  at  the  time  of 
pupation  of  the  larvae,  scrapes  away  the  wax  by  which  the 
cocoons  are  covered,  thus  facilitating  the  escape  of  the  per- 
fect Insect,  and,  it  may  also  be,  aiding  the  access  of  air  to  the 
pupa.  The  colony  at  first  grows  very  slowly,  as  the  queen  can, 
unaided,  feed  only  a  small  number  of  larvae.  But  after  she 
receives  the  assistance  of  the  first  batch  of  workers  much  more 
rapid  progress  is  made,  the  queen  greatly  restricting  her  labours, 
and  occupying  herself  with  the  laying  of  eggs;  a  process  that 
now  proceeds  more  and  more  rapidly,  the  queen  in  some  cases 
scarcely  ever  leaving  the  nest,  and  in  others  even  becoming 
incapable  of  flight.  The  females  produced  during  the  inter- 
mediate period  of  the  colony  are  smaller  than  the  mother,  but 
supplement  her  in  the  process  of  egg  -  laying,  as  also  do  the 
workers  to  a  greater  or  less  extent.  The  conditions  that  deter- 
mine the  egg-laying  powers  of  these  small  females  and  workers 
are  apparently  unknown,  but  it  is  ascertained  that  these  powers 
vary  greatly  in  different  cases,  so  that  if  the  true  queen  die  the 
continuation  of  the  colony  is  sometimes  effectively  carried  on  by 
these  her  former  subordinates.  In  other  cases,  however,  the 
reverse  happens,  and  none  of  the  inhabitants  may  be  capable  of 
producing  eggs :  in  this  event  two  conditions  may  be  present ; 
either  larvae  may  exist  in  the  nest,  or  they  may  be  absent.  In 
the  former  case  the  workers  provide  them  with  food,  and  the 


56  HYMENOPTERA  CHAP. 

colony  may  thus  still  be  continued ;  but  in  the  latter  case, 
there  being  no  profitable  occupation  for  the  bees  to  follow, 
they  spend  the  greater  part  of  the  time  sitting  at  home  in  the 
nest. 

Supposing  all  to  go  well  with  the  colony  it  increases  very 
greatly,  but  its  prosperity  is  checked  in  the  autumn ;  at  this 
period  large  numbers  of  males  are  produced  as  well  as  new 
queens,  and  thereafter  the  colony  comes  to  an  end,  only  a  few 
fertilised  females  surviving  the  winter,  each  one  to  commence  for 
herself  a  new  colony  in  the  ensuing  spring. 

The  interior  of  the  nest  of  a  bumble-bee  (Boinbus)  frequently 
presents  a  very  irregular  appearance ;  this  is  largely  owing  to  the 
fact  that  these  bees  do  not  use  the  cells  as  cradles  twice,  but  form 
others  as  they  may  be  required,  on  the  old  remains.  The  cells, 
moreover,  are  of  different  sizes,  those  that  produce  workers  being 
the  smallest,  those  that  cradle  females  being  the  largest,  while 
those  in  which  males  are  reared  are  intermediate  in  size. 
Although  the  old  cells  are  not  used  a  second  time  for  rearing 
brood  they  are  nevertheless  frequently  adapted  to  the  purposes 
of  receptacles  for  pollen  and  for  honey,  and  for  these  objects  they 
may  be  increased  in  size  and  altered  in  form. 

It  may  be  gathered  from  various  records  that  the  period 
required  to  complete  the  development  of  the  individual  Bombus 
about  midsummer  is  four  weeks  from  the  deposition  of  the  egg 
to  the  emergence  of  the  perfect  Insect,  but  exact  details  and 
information  as  to  whether  this  period  varies  with  the  sex  of  the 
Insect  developed  are  not  to  be  found.  The  records  do  not 
afford  any  reason  for  supposing  that  such  distinction  will  be 
found  to  exist :  the  size  of  the  cells  appears  the  only  correlation, 
suggested  by  the  facts  yet  known,  between  the  sex  of  the  in- 
dividual and  the  circumstances  of  development. 

The  colonies  of  Bombus  vary  greatly  in  prosperity,  if  W7e  take 
as  the  test  of  this  the  number  of  individuals  produced  in  a 
colony.  They  never,  however,  attain  anything  at  all  approach- 
ing to  the  vast  number  of  individuals  that  compose  a  large  colony 
of  wasps,  or  that  exist  in  the  crowded  societies  of  the  more 
perfectly  social  bees.  A  populous  colony  of  a  subterranean 
Bombus  may  attain  the  number  of  oOO  or  400  individuals. 
Those  that  dwell  on  the  surface  are  as  a  rule  much  less  populous, 
as  they  are  less  protected,  so  that  changes  of  weather  are  more 


i  SOCIALES NESTS  OF  BOMBUS  57 

prejudicial  to  them.  According  to  Smith,  the  average  number 
of  a  colony  of  B.  muscorum  in  the  autumn  in  this  country  is 
about  120 — viz.  25  females,  36  males,  59  workers.  No  mode 
of  increasing  the  nests  in  a  systematic  manner  exists  in  this 
genus ;  they  do  not  place  the  cells  in  stories  as  the  wasps  do  ; 
and  this  is  the  case  notwithstanding  the  fact  that  a  cell  is  not 
twice  used  for  the  rearing  of  young.  When  the  ground-space 
available  for  cell-building  is  filled  the  Bombus  begins  another 
series  of  cells  on  the  ruins  of  the  first  one.  From  this  reason 
old  nests  have  a  very  irregular  appearance,  and  this  condition  of 
seeming  disorder  is  greatly  increased  by  the  very  different  sizes 
of  the  cells  themselves.  We  have  already  alluded  to  some  of 
these  cells,  more  particularly  to  those  of  different  capacities  to 
suit  the  sexes  of  the  individuals  to  be  reared  in  them.  In 
addition  to  these  there  are  honey  -  tubs,  pollen-tubs,  and 
the  cells  of  the  Psithyrus  (Fig.  23),  the  parasitic  but  friendly 
inmates  of  the  Bombus- nests.  A  nest  of  Bombus,  exhibiting 
the  various  pots  projecting  from  the  remains  of  empty  and 
partially  destroyed  cells,  presents,  as  may  well  be  imagined,  a  very 
curious  appearance.  Some  of  the  old  cells  apparently  are  partly 
destroyed  for  the  sake  of  the  material  they  are  composed  of. 
Others  are  formed  into  honey- tubs,  of  a  make-shift  nature.  It 
must  be  recollected  that,  as  a  colony  increases,  stores  of  pro- 
visions become  absolutely  necessary,  otherwise  in  bad  weather 
the  larvae  could  not  be  fed.  In  good  weather,  and  when  flowers 
abound,  these  bees  collect  and  store  honey  in  abundance ;  in 
addition  to  placing  it  in  the  empty  pupa-cells,  they  also  form 
for  it  special  receptacles ;  these  are  delicate  cells  made  entirely 
of  wax  filled  with  honey,  and  are  always  left  open  for  the  benefit 
of  the  community.  The  existence  of  these  honey  -  tubs  in 
1  tumble-bees'  nests  has  become  known  to  our  country  urchins, 
whose  love  for  honey  and  for  the  sport  of  bee-baiting  leads  to 
wholesale  destruction  of  the  nests.  According  to  Hoffer,  special 
tubs  for  the  storing  of  pollen  are  sometimes  formed ;  these  are 
much  taller  than  the  other  cells.  The  Psithyrus  that  live  in  the 
nests  with  the  Bombus  are  generally  somewhat  larger  than  the 
latter,  and  consequently  their  cells  may  be  distinguished  in  the 
nests  by  their  larger  size.  A  bumble-bees'  nest,  composed  of  all 
these  heterogenous  chambers  rising  out  of  the  ruins  of  former 
layers  of  cells,  presents  a  scene  of  such  apparent  disorder  that 


58  HYMENOPTERA  CHAP. 

many  have  declared  that  the  bumble-bees  do  not  know  how  to 
build. 

Although  the  species  of  Bombus  are  not  comparable  with  the 
hive-bee  in  respect  of  the  perfection  and  intelligent  nature  of 
their  work,  jet  they  are  very  industrious  Insects,  and  the  con- 
struction of  the  dwelling-places  of  the  subterranean  species  is 
said  to  be  carried  out  in  some  cases  with  considerable  skill,  a 
dome  of  wax  being  formed  as  a  sort  of  roof  over  the  brood  cells. 
Some  work  even  at  night.  Tea  has  recorded  the  capture  of  a 
species  in  Upper  Burmah  working  by  moonlight,  and  the  same 
industry  may  be  observed  in  this  country  if  there  be  sufficient 
heat  as  well  as  light.  Godart,  about  200  years  ago,  stated  that 
a  trumpeter-bee  is  kept  in  some  nests  to  rouse  the  denizens  to 
work  in  the  morning :  this  has  been  treated  as  a  fable  by 
subsequent  writers,  but  is  confirmed  in  a  circumstantial  manner 
by  Hoffer,  who  observed  the  performance  in  a  nest  of  B.  ruderatus 
in  his  laboratory.  On  the  trumpeter  being  taken  away  its  office 
was  the  following  morning  filled  by  another  individual.  The 
trumpeting  was  done  as  early  as  three  or  four  o'clock  in  the 
morning,  and  it  is  by  no  means  impossible  that  the  earliness  of 
the  hour  may  have  had  something  to  do  with  the  fact  that  for 
200  years  no  one  confirmed  the  old  naturalist's  observation. 

One  of  the  most  curious  facts  in  connection  with  Bomlnis  is 
the  excessive  variation  that  many  of  the  species  display  in  the 
colour  of  the  beautiful  hair  with  which  they  are  so  abundantly 
provided.  There  is  not  only  usually  a  difference  between  the 
sexes  in  this  respect,  but  also  extreme  variation  within  the 
limits  of  the  same  sex,  more  especially  in  the  case  of  the  males 
and  workers ;  there  is  also  an  astonishing  difference  in  the  size 
of  individuals.  These  variations  are  carried  to  such  an  extent 
that  it  is  almost  impossible  to  discriminate  all  the  varieties  of  a 
species  by  inspection  of  the  superficial  characters.  The  struc- 
tures peculiar  to  the  male,  as  well  as  the  sting  of  the  female, 
enable  the  species  to  be  determined  with  tolerable  certainty. 
Cholodkovsky,1  on  whose  authority  this  statement  as  to  the  sting 
is  n uide,  has  not  examined  it  iu  the  workers,  so  that  we  do  not 
know  whether  it  is  as  invariable  in  them  as  he  states  it  to  be 
in  queens  of  the  same  species.  According  to  Handlirsch,'  each 

1   Zont.  An;,  vii.  1884,  p.  312. 
2  SJ3.  Gcs.  Wien.  xxxviii.  1888,  p.  34. 


SOCIALES PSITHYRUS  59 


species  of  Bombus  has  the  capacity  of  variation,  and  many  of  the 
varieties  are  found  in  one  nest,  that  is,  among  the  offspring  of  a 
single  pair  of  the  species,  but  many  of  the  variations  are  restricted 
to  certain  localities.  Some  of  the  forms  can  be  considered  as 
actual  ("  fertige  ")  species,  intermediate  forms  not  being  found,  and 
even  the  characters  by  which  species  are  recognised  being  some- 
what modified.  As  examples  of  this  he  mentions  Bombus  silvarum 
and  B.  arenicula,  B.pratorum  and  B.  scrim  sJtiranus.  In  other  cases, 
however,  the  varieties  are  not  so  discontinuous,  intermediate  forms 
being  numerous ;  this  condition  is  more  common  than  the  one  we 
have  previously  described  ;  B.  terrestris,  B.  horturum,  B.  lapidarius 
and  B.  pomorum  are  examples  of  these  variable  species.  The 
variation  runs  to  a  considerable  extent  in  parallel  lines  in  the 
different  species,  there  being  a  dark  and  a  light  form  of  each  ;  also 
each  species  that  has  a  white  termination  to  the  body  appears  in 
a  form  with  a  red  termination,  and  vice  versd.  In  the  Caucasus 
many  species  that  have  everywhere  else  yellow  bands  possess 
them  white ;  and  in  Corsica  there  are  species  that  are  entirely 
black,  with  a  red  termination  to  the  body,  though  in  continental 
Europe  the  same  species  exhibit  yellow  bands  and  a  white  ter- 
mination to  the  body.  AVith  so  much  variation  it  will  be  readily 
believed  that  much  remains  to  be  done  in  the  study  of  this 
fascinating  genus.  It  is  rich  in  species  in  the  Northern  hemi- 
sphere, but  poor  in  the  Southern  one,  and  in  both  the  Ethiopian 
and  Australian  regions  it  is  thought  to  be  entirely  wanting. 

The  species  of  the  genus  Psithyrus  (Apatkus  of  many  authors) 
inhabit  the  nests  of  Bombus;  although  less  numerous  than  the 
species  of  the  latter  genus,  they  also  are  widely  distributed.  They 
are  so  like  Bombus  in  appearance  that  they  were  not  distinguished 
from  them  by  the  earlier  entomologists  ;  and  what  is  still  more 
remarkable,  each  species  of  Psithyrus  resembles  the  Bombus  with 
which  it  usually  lives.  There  appear,  however,  to  be  occasional 
exceptions  to  this  rule,  Smith  having  seen  one  of  the  yellow- 
banded  Psithyrus  in  the  nest  of  a  red-tailed  Bombus.  Psitliyrus 
is  chiefly  distinguished  from  Bombus  by  the  absence  of  certain 
characters  that  fit  the  latter  Insects  for  their  industrial  life ;  the 
hind  tibiae  have  no  smooth  space  for  the  conveyance  of  pollen, 
and,  so  far  as  is  known,  there  are  only  two  sexes,  males  and  per- 
fect females.  The  Bombus  and  Psithyrus  live  together  on  the 
best  terms,  and  it  appears  probable  that  the  latter  do  the  former 


6o 


HYMENOPTERA 


CHAP. 


no  harm  beyond  appropriating  a  portion  of  their  food  supplies. 
Schmiedeknecht  says  they  are  commensals,  not  parasites  ;  Lut  it 
must  be  admitted  that  singularly  few  descriptions  of  the  habits 
and  life-histories  of  these  interesting  Insects  have  been  recorded. 

Hoffer  has,  however, 
made  a  few  direct 
observations  which 
confirm,  and  at  the 
same  time  make 
UK  ire  definite,  the 
vague  ideas  that 
have  been  generally 
prevalent  among 
He 
took 


entomologists. 


FIG.  23. — Psitliyrus  restalix,  Britain.     A.  Female,    x  :]  ; 
B.    outer  side  of  hind  lee. 


found  and 
home  a  nest 
bus  variabilis,  which 
contained  also  a 
female  of  Psitliyrus 

ccinipestris,  so  that  he  was  able  to  make  observations  on  the  two. 
The  PsitJiyrus  was  much  less  industrious  than  the  Bombus,  and 
only  left  the  nest  somewhat  before  noon,  returning  home  again 
towards  evening  ;  after  about  a  month  this  specimen  became  still 
more  inactive,  and  passed  entire  days  in  the  nest,  occupying  itself 
in  consuming  the  stores  of  honey  of  its  hosts,  of  which  very  large 
quantities  were  absorbed,  the  Psitliyrus  being  much  larger  than  the 
host-bee.  The  cells  in  which  the  young  of  the  Psithyrus  are  hatched 
are  very  much  larger  than  those  of  the  Bombus,  and,  it  may  therefore 
be  presumed,  are  formed  by  the  Psitliyrus  itself,  for  it  can  scarcely 
be  supposed  that  the  Bv  minis  carries  its  complaisance  so  far  as 
to  construct  a  cell  specially  adapted  to  the  superior  stature  of  its 
uninvited  boarder.  When  a  Psitkyrus  has  been  for  some  time  a 
regular  inhabitant  of  a  nest,  the  Bombus  take  its  return  home  from 
time  to  time  as  a  matter  of  course,  displaying  no  emotion  what- 
ever at  its  entry.  Occasionally  Hoffer  tried  the  introduction  of 
a  Psitliyrus  to  a  nest  that  had  not  previously  had  one  as  an  in- 
mate. The  new  arrival  caused  a  great  hubbub  among  the  Bombus, 
which  rushed  to  it  as  if  to  attack  it,  but  did  not  do  so,  and  the 
alarm  soon  subsided,  the  Psitliyrus  taking  up  the  position  in 
the  nest  usually  affected  by  the  individuals  of  the  species.  On 


i  SOCIALES STINGLESS  BEES  6  I 

introducing  a  female  Psitliyrus  to  a  nest  of  Bombus  in  which  a 
Psitliyrus  was  already  present  as  an  established  guest,  the  latter 
asserted  its  rights  and  drove  away  the  new  comer.  Hoffer  also 
tried  the  experiment  of  placing  a  Psitliyrus  campestris  in  the  nest 
of  Bombus  lapidarius — a  species  to  which  it  was  a  stranger ;  not- 
withstanding its  haste  to  fly  away,  it  was  at  once  attacked  by 
the  Bombus,  who  pulled  it  about  but  did  not  attempt  to  sting  it. 

When  Psitliyrus  is  present  in  a  nest  of  Bombus  it  apparently 
affects  the  inhabitants  only  by  diminishing  their  stores  of  food  to 
so  great  an  extent  that  the  colony  remains  small  instead  of  largely 
increasing  in  numbers.  Although  Bombus  variabilis,  when  left 
to  itself,  increases  the  number  of  individuals  in  a  colony  to  200 
or  more,  Hoffer  found  in  a  nest  in  which  Psithyrus  was  present, 
that  on  the  1st  of  September  the  assemblage  consisted  only  of  a 
queen  Bombus  and  fifteen  workers,  together  with  eighteen  speci- 
mens of  the  Psitliyrus,  eight  of  these  being  females. 

The  nests  of  Bombus  are  destroyed  by  several  animals,  probably 
for  the  sake  of  the  honey  contained  in  the  pots ;  various  kinds 
of  small  mammals,  such  as  mice,  the  weasel,  and  even  the  fox, 
are  known  to  destroy  them ;  and  quite  a  fauna  of  Insects  may  be 
found  in  them  ;  the  relations  of  these  to  their  hosts  are  very  little 
known,  but  some  undoubtedly  destroy  the  bees'  larvae,  as  in  the 
case  of  Meloe,  Mutilla  and  Conops.  Birds  do  not  as  a  rule  attack 
these  bees,  though  the  bee-eater,  M<:r<>p*  "jiii'stcr,  has  been  known 
to  feed  on  them  very  heavily. 

The  genera  of  social  bees  known  as  Melipona,  Trigona  or  Tetra- 
gona,  may,  according  to  recent  authorities,  be  all  included  in  one 
genus,  Melipona.  Some  of  these  Insects  are  amongst  the  smallest 
of  bees,  so  that  one,  or  more,  species  go  by  the  name  of  "  Mosquito- 
bees."  The  species  appear  to  be  numerous,  and  occur  in  most  of  the 
tropical  parts  of  the  continents  of  the  world,  but  unfortunately 
very  little  is  known  as  to  their  life-histories  or  economics  ;  they 
are  said  to  form  communities  consisting  at  times  of  a  countless 
number  of  individuals ;  but  it  has  not  been  thoroughly  ascer- 
tained whether  these  are  the  produce  of  a  single  queen,  as  in 
the  case  of  the  hive-bee,  or  whether  there  may  be  more  than  one 
egg-producer  in  each  community.  The  late  F.  Smith  thought 
the  former  of  these  alternatives  would  prove  to  lie  correct. 
These  mosquito-bees  are  frequently  spoken  of  as  stingless  bees, 
but  this  is  not  quite  correct,  for  although  they  do  not  sting, 


62 


HYMENOPTERA 


CHAP. 


von  Ihering1  says  that  all  the  essential  elements  of  the  sting 
are  present,  the  pointed  or  penetrating  part  of  the  apparatus 
being  stunted. 

It  would  serve  no  useful  purpose  to  attempt  to  construct  the 
social  history  of  these  stingless  bees  from  the  numerous  brief 
scattered  accounts  in  entomological  literature,  for  they  refer  to 
different  species  ;  it  is,  however,  positively  stated  by  Smith  on  the 
authority  of  Peckolt  ~  that  Trigona  mosquito  sends  off  swarms  after- 
the  manner  of  the  hive-bee  in  this  country,  and  that  after  search- 
ing six  hives  only  one  royal  female  could  be  found  in  each. 

The  nests  of  many  of  these  little   bees   are   rich  in  honey,  and 
they  have  a  host  of  enemies  from  man  and  monkeys  downwards  : 

and  as  they  do  not  defend 
themselves  by  stinging,  it  might 
be  supposed  they  would  have 
but  a  poor  time  of  it.  From 
the  accounts  that  have  been 
published  we  may,  however, 
gather  that  they  are  rich  in 
devices  for  the  protection  of 
their  nests,  and  for  the  exclu- 
sion of  intruders.  Bates  has 
given  some  particulars  as  to 
Mi-lipona,  interrupts  (fasci- 
culat(i) ;  it  is  about  one-third 
shorter  than  the  hive-bee,  and  its  colonies  are  composed  of  an  im- 
mense number  of  individuals.  The  workers  are  usually  occupied 
in  gathering  pollen  ;  but  they  also  collect  clay  in  a  similar  manner, 
and  convey  it  to  the  nest,  where  it  is  used  for  building  a  wall  to 
complete  the  fortification  of  the  nest,  which  is  placed  either  in  a 
suitable  bank,  or  in  a  trunk  of  a  tree;  in  either  situation  it  is 
completely  built  in  with  clay.  A  nest  which  Bates  saw  opened 
contained  about  two  quarts  of  pleasantly-tasted  liquid  honey. 
Forty-five  species  of  these  little  bees  were  found  in  different 
parts  of  the  Amazons  Valley,  the  largest  kind  being  half  an  inch 
in  length,  the  smallest  very  minute,  not  more  than  one-twelfth 
of  an  inch.  These  little  creatures  are  thus  masons  as  well 
as  workers  in  wax  and  resin,  and  they  are  also  gatherers  of 
nectar,  pollen,  and  resin. 

1    Hut.  Xtn-hr.  xii.  1866,  p.  177.  '   Tr.  cut.  Xoc.  London,  1868,  p.  133. 


FIG.  24. — Mclipima  sp.  9.     Amazons. 


i  SOCIALES STINGLESS  BEES  63 

According  to  Gosse,  one  of  these  bees  is  well  known  in  Jamaica, 
where  they  are  called  "  Angelitos,"  in  consquence  of  their  not  sting- 
ing people.  He  observed  a  nest  of  this  bee  in  a  tree,  and  found 
it  to  be  much  infested  by  black  ants  anxious  to  obtain  entrance 
to  it ;  three  bees,  however,  stood  sentinel  in  the  entrance,  so  as  to 
completely  block  it  and  keep  out  intruders,  but  the  middle  bee 
moved  on  one  side  out  of  the  way  directly  one  of  its  fellows 
wished  to  come  in  or  out  of  the  nest.  The  honey  accumulated 
by  this  species  is  kept  in  clusters  of  cups  about  the  size  of  a 
pigeon's  egg,  at  the  bottom  of  the  hive  and  away  from  the  brood- 
cells.  The  queen  or  mother-bee  is  lighter  in  colour  than  the 
others,  and  has  the  hind  body  twice  the  length  of  theirs. 

Hoc-kings  1  has  given  us  some  details  as  to  the  natural  history 
of  two  of  these  bees  that  inhabit  Australia,  where  they  are  called 
"  Karbi "  and  "  Kootchar,"  the  first  being,  it  is  supposed,  Trigona 
carbonaria,  Smith:  it  is  usually  about  three -sixteenths  of  an 
inch  in  length,  the  queen,  when  fully  developed,  being  nearly 
twice  that  length.  The  comb  is  built  in  a  most  peculiar  form, 
being,  it  is  said,  in  the  shape  of  a  spiral  staircase,  and  tapering 
towards  the  ends :  honey -pots  and  pollen  are  constructed  for 
the  storage  of  food.  The  comb  is  encased  in  wax,  and  outside  it 
a  labyrinth  of  waxen  passages  is  formed.  The  entrance  to  the 
colony  is  guarded  by  a  line  of  bees  who  inspect  every  one  that 
arrives,  and  it  is  surprising  to  see  how  soon  a  stranger  is  dis- 
covered and  pounced  upon  before  it  has  time  even  to  alight ;  the 
intruder,  when  caught,  is  held  by  several  bees,  who  put  it  on  the 
rack  by  holding  and  stretching  out  its  limbs  to  their  full  extent, 
retaining  it  in  this  position  for  as  long  as  an  hour,  by  which  time 
the  unfortunate  prisoner  is  usually  dead.  These  bees,  as  well  as 
'many  other  allied  species,  fight  desperately  with  their  mandibles, 
and  are  apparently  of  a  very  fierce  disposition.  The  other 
species,  called  "  Kootchar,"  is  said  to  produce  a  very  large  number 
of  drones,  and  the  habits  and  dispositions  of  the  bees  differ  con- 
siderably from  those  of  the  "  Karbi "  :  the  entrance  to  their  hive  is 
guarded  by  a  pipe  of  propolis  (a  sort  of  resinous  wax)  about  an  inch 
in  length,  having  an  exceedingly  sticky  outer  edge,  and  it  is  by  this 
pipe  alone  that  access  to  the  interior  can  be  gained.  At  night 
the  entrance  is  closed  by  numerous  minute  globules  of  semi-fluid 
gum  placed  against  it,  thus  forming  a  thin  wall  full  of  air-holes. 

1   Tr.  cnt.  Soc.  London,  1884,  p.  149. 


64  HYMENOPTERA 


CHAP. 


The  colonies  of  "  Kootchar  "  can  be  united  by  taking  away  a  queen 
and  then  packing  her  brood-nest,  bees  and  all,  against  that  of 
the  colony  it  is  to  be  joined  to.  This  cannot  be  done  with  the 
'  Karbi."  The  account  given  by  Mr.  Hockings  contains  a  great 
many  other  interesting  details,  and  there  can  be  no  doubt  that 
a  full  account  of  the  natural  history  of  these  Insects  would  be 
very  instructive. 

Fritz  Miiller  has  recorded  a  singular  case  bearing  on  the 
instinct  of  these  social  Insects :  he  says  that  a  nest  of  a  small 
Triyona  was  built  in  a  hollow  tree,  and  that  as  a  consequence  of 
the  irregularity  of  the  hole  the  bees  were  obliged  to  give  a  very 
irregular  shape  to  their  combs  of  honey.  These  bees  were 
captured  and  put  in  a  spacious  box  (presumably  together  with 
the  irregular  comb,  but  this  he  unfortunately  does  not  mention) : 
after  a  year,  "  when  perhaps  not  a  single  bee  survived  of  those 
which  had  come  from  the  canella  tree,"  they  still  continued  to 
build  irregular  combs,  though  quite  regular  combs  were  built  by 
several  other  communities  of  the  same  species  that  he  had  kept. 
These  bees,  he  also  tells  us,  do  not  use  pure  wax  for  the  construc- 
tion of  their  combs,  but  mix  it  with  resin  or  gum  that  gives  it  a 
peculiar  odour  and  appearance.  He  captured  two  communities 
of  a  common  Melipona,  one  of  which  had  the  combs  made  of  dark 
reddish  brown,  the  other  of  pale  yellowish  brown,  wax,  and  in 
captivity  in  a  distant  locality  each  of  the  twro  communities 
continued  to  form  its  comb  in  the  same  way,  thus  showing  the 
continuity  that  prevails  in  these  cases  as  long  as  circumstances 
permit.  Miiller  thinks  this  due  to  imitation,  but  it  seems  at 
least  as  probable  that  it  is  due  to  perception  of  the  properties  of 
the  nest.  The  nest  has  a  certain  colour  that  the  worker-bee 
matches. 

Several  species  of  the  Melipona,  and  Triijoim  were  imported 
from  Brazil  to  France,  and  kept  there  for  some  time  in  captivity 
by  M.  Drory.  Girard  has  published1  some  details  as  to  these 
colonies,  and  is  of  opinion  that  some  of  them  indicate  an  in- 
telligence or  instinct  superior  to  that  of  the  honey-bee.  The 
<|iir-rn-bce  of  M.  scutell<irix  seems  to  display  more  intelligence 
than  the  corresponding  sex  of  A.  mellifica.  The  mode  of  feeding 
the  larvae  apparently  differs  from  that  of  A.  mellifica,  a  provision 
of  pollen  being  first  placed  in  the  cell,  then  some  honey  ;  when 

1   .hni.  Soc.  enl.  France  (5),  iv.  187-4,  p.  567. 


i  SOCIALES HONEY-BEE  65 

sufficient  food  for  the  whole  consumption  of  a  larva  is  accumulated 
the  queen  deposits  an  egg  in  the  cell,  which  is  at  once  completely 
closed  by  the  worker.  The  interior  of  the  abode  of  these  bees  is 
quite  dark,  only  a  very  small  orifice  being  left,  and  in  this  a  sen- 
tinel is  constantly  on  the  alert.  The  same  writer  states  that 
Tr'njona  crassipcs  has  the  very  peculiar  habit  of  always  locating 
its  brood-comb  in  the  nest  of  a  species  of  Termes. 

The  honey-bee,  Apis  mellijiccc  (Fig.  6),  is  considered  the  highest 
form  attained  by  the  Anthophilous  division  of  the  Hymenoptera. 
The  differentiation  of  the  three  forms,  male,  female,  and  worker, 
is  here  carried  to  a  greater  degree  of  perfection  than  in  the  other 
bees.  The  drones  are  the  males ;  the  individuals  we  see  gather- 
ing honey  are  always  workers,  neither  the  male  nor  the  female  in 
this  species  taking  any  part  in  procuring  food  for  themselves  or 
for  the  colony.  In  addition  to  this  the  colonies  formed  may  be 
described  as  permanent :  they  do  not  come  to  an  end  at  the  close 
of  one  season,  and  provision  is  made  for  the  formation  of  a  new 
colony  while  the  old  one  still  persists,  by  means  of  a  peculiar  pro- 
cess called  swarming.  The  life-history  of  Apis  mellifica  and  its 
anatomy  and  physiology  have  been  discussed  in  a  whole  library 
of  works,  and  we  need  only  notice  the  chief  features.  When  a 
swarm  of  bees  leaves  a  hive  it  consists  of  the  queen-bee  or 
female,  and  a  number  of  workers,  these  latter  being,  in  fact,  the 
surplus  population  that  has  been  produced  in  the  hive.  The 
swarm  is  not  a  nuptial  flight,  as  is  often  supposed,  but  an  act 
of  emigration.  When  this  swarm  has  been  housed,  the  bees 
commence  operations  in  their  new  quarters,  by  secreting  wax  ; 
they  are  enabled  to  do  this  by  having  consumed  much  saccharine 
food ;  the  wax  is  produced  by  means  of  glands  in  the  hind-body 
over  the  inner  faces  of  the  ventral  plates  of  the  abdominal  rings, 
and  it  makes  its  appearance  there,  after  passing  from  the  interior 
of  the  body  through  some  peculiar  membranes  on  the  ventral 
segments,  in  the  form  of  thin  projecting  plates.  These  the  bee 
takes  off  with  an  apparatus  on  the  hind  pair  of  legs  and  applies, 
after  working  up  with  the  mandibles,  to  form  the  cells  in 
which  young  ones  are  to  be  reared  and  food  stored.  A  large 
number  of  bees  working  in  common  thus  produce  the  regular 
and  beautiful  structure  known  as  the  comb  ;  the  queen  afterwards 
lays  an  egg  in  each  cell,  and  as  these  soon  hatch,  great  labour  is 
thrown  on  the  workers,  which  have  then  to  feed  the  young  ;  this 
VOL.  VI  F 


66  HYMENOPTERA  CHAP. 

they  do  by  eating  honey  and  pollen,  which,  being  formed  into  a 
sort  of  pap  by  a  portion  of  their  digestive  organs,  is  then  re- 
gurgitated and  given  to  the  young,  a  quantity  of  it  being  placed 
in  the  cell,  so  that  the  larva  is  bathed  by  it,  and  possibly  may 
absorb  the  food  by  the  skin  as  well  as  the  mouth.  When  the 
colony  is  in  good  progress  and  young  bees  emerge,  these  act  as 
nurses,  the  older  ones  cease  to  prepare  food  and  act  as  foragers, 
bringing  in  honey  and  pollen  which  are  each  stored  in  separate 
cells.  The  larva  in  the  cell  increases  its  size  and  sheds  a  very 
delicate  skin  several  times ;  when  the  larva  has  reached  its 
full  size  no  more  food  is  supplied,  but  the  worker-bees  seal  up 
the  cell  by  means  of  a  cover  formed  of  pollen  and  wax,  in  such  a 
manner  as  to  be  pervious  to  air :  sealed  up  in  the  cell  the  larva 
spins  a  cocoon  for  itself,  remains  therein  for  a  little  time  as  a 
larva,  then  changes  to  a  pupa,  and  thereafter  bites  its  way  out 
through  the  cover  of  the  cell,  and  appears  for  the  first  time  as 
a  new  being  in  the  form  of  a  worker-bee ;  the  whole  process  of 
development  from  the  egg-state  to  the  perfect  condition  of  the 
worker-bee  occupies  about  three  weeks. 

When  the  denizens  of  a  hive  are  about  to  produce  another 
queen,  one  or  more  royal  cells  are  formed ;  these  are  much 
larger  than  the  ordinary  worker-cells,  and  of  a  quite  different 
form.  In  this  cell  is  placed  an  egg,  not  differing  in  any  respect 
from  the  egg  that,  if  placed  in  an  ordinary  cell,  produces  a 
worker ;  when  the  egg  has  produced  a  larva  this  is  tended  with 
great  care  and  fed  throughout  its  life  with  royal  jelly.  This 
food  appears  to  be  the  same  as  that  supplied  to  an  ordinary 
worker-larva  when  it  is  first  hatched  ;  but  there  is  this  differ- 
ence, that  whereas  the  worker-larva  is  weaned,  and  supplied, 
after  the  first  period  of  its  existence,  with  food  consisting  largely 
of  honey,  pollen  and  water,  the  queen-larva  is  supplied  with  the 
pap  or  royal  jelly  until  it  is  full  grown.  Some  difference  of 
opinion  exists  as  to  this  royal  jelly,  some  thinking  that  it  is  a 
different  substance  from  what  the  workers  are  fed  with  ;  and  it 
is  by  no  means  improbable  that  there  may  be  some  difference  in 
the  secretion  of  the  glands  that  furnish  a  part  of  the  material 
composing  the  pap.  The  queen  is  produced  more  rapidly  than 
workers  are,  about  sixteen  days  being  occupied  in  the  process  of 
her  development.  Only  one  queen  is  allowed  in  a  hive  at  a 
time ;  so  that  when  several  queen-cells  are  formed,  and  queen- 


i  SOCIALES HONEY-BEE  6/ 

• 

larvae  nurtured  in  them,  the  first  one  that  is  developed  into  a 
perfect  queen  goes  round  and  stings  the  royal  nymphs  to  death 
while  they  are  still  in  their  cells.  The  production  of  drones  is 
supposed  to  depend  chiefly  on  the  nature  of  the  egg  laid  by  the 
queen ;  it  being  considered  that  an  unfertilised  egg  is  deposited 
for  this  purpose.  There  is  still  some  doubt  on  this  point,  how- 
ever. Though  there  is  no  doubt  that  drones  are  produced  in 
great  numbers  from  unfertilised  eggs,  yet  there  is  not  evidence 
that  they  cannot  also  be  produced  from  fertilised  eggs.1  The 
drone-cells  are  somewhat  larger  than  the  ordinary  worker-cells, 
but  this  is  probably  not  of  much  import,  and  it  is  said  that  the 
larvae  intended  to  produce  drones  receive  a  greater  proportion  of 
pap  than  worker-larvae  do  :  about  twenty-four  days  are  required 
to  produce  a  drone  from  the  egg. 

From  this  sketch  it  will  be  seen  that  the  production  of  the 
worker  (or  third  sex,  as  it  is  improperly  called,  the  workers 
being  really  females  atrophied  in  some  points  and  specially 
developed  in  others)  is  dependent  on  the  social  life,  in  so  far  at 
any  rate  as  the  special  feeding  is  concerned.  There  is  good 
reason  for  supposing  that  A.  mellifica  has  been  kept  in  a  state  of 
domestication  or  captivity  for  an  enormous  period  of  time ;  and 
this  condition  has  probably  led  to  an  increase  of  its  natural 
peculiarities,  or  perhaps  we  should  say  to  a  change  in  them  to 
suit  a  life  of  confinement.  This  is  certainly  the  case  in  regard 
to  swarming,  for  this  process  takes  place  with  comparative 
irregularity  in  Apis  mclUfica  in  a  wild  condition.  The  killing  of 
superfluous  queens  is  also  probably  a  phenomenon  of  captivity, 
for  it  varies  even  now  in  accordance  with  the  numbers  of  the 
colony.  It  is  interesting  to  notice  that  in  confinement  when  a 
swarm  goes  from  the  hive  it  is  the  old  queen  that  accompanies 
it,  and  this  swarm  as  a  rule  settles  clown  near  the  old  hive,  so 
that  the  queen-bee  being  already  fertilised,  the  new  swarm  and 
its  subsequent  increase  are  nothing  but  a  division  of  the  old 
hive,  the  total  products  of  the  two  having  but  a  single  father 
and  mother.  When  a  second  swarm  goes  off  from  a  hive  it  is 
accompanied  by  a  young  queen,  who  frequently,  perhaps,  in  the 
majority  of  cases,  is  unfertilised  ;  this  swarm  is  apt  to  fly  for 
long  distances,  so  that  the  probability  of  cross-fertilisation  is 

1  See  Perez,  Act.  Soc.  Bordeaux,  xxxiii.  1880,  p.  Ixv.  ;  and  Cameron,  Tr.  Soc. 
Glasgow,  11.  s.  ii.  1889,  }'.  194. 


68  IIVMENOPTERA 


CHAP. 


greatly  increased,  as  the  fertilisation  of  the  young  new  queen  is 
effected  during  a  solitary  flight  she  makes  after  the  colony  has 
settled  down.  But  in  a  state  of  nature  the  colonies  do  not  send 
off  swarms  every  year  or  once  a -year,  but  increase  to  an  enormous 
extent,  going  for  years  without  swarming,  and  then  when  their 
home  is  really  filled  up  send  off,  it  may  he  presumed,  a  number 
of  swarms  in  one  year.  Thus  the  phenomena  of  bee-life  in  a 
wild  condition  differ  considerably  from  those  we  see  in.  artifi- 
cial confinement.  And  this  difference  is  probably  greatly  accen- 
tuated by  the  action  of  parasites,  the  proportions  of  which  to  their 
guests  are  in  a  state  of  nature  liable  to  become  very  great ;  as 
we  have  seen  to  be  the  case  in  Jjombus. 

Under  these  circumstances  it  is  not  a  matter  for  surprise 
when  we  find  that  the  honey-bee  has  formed  distinct  races 
analogous  to  those  that  exist  in  the  case  of  the  domesticated 
vertebrate  animals.  The  knowledge  of  these  races  is,  however, 
at  present  very  little  advanced,  and  is  complicated  by  the  fact 
that  only  imperfect  information  exists  as  to  the  true  species 
of  the  genus  Apis.  There  is  a  bee  very  like  our  common  honey- 
bee found  in  southern  Europe  called  A.  ligusiica ;  this  is 
certainly  a  variety  of  A.  mellifica,  and  the  same  remark  applies 
to  a  bee  found  in  Egypt,  and  called  A.fasciata.  This  gives  the 
honey-bee  a  very  wide  distribution,  extending  possibly  over  the 
whole  of  the  palaearctic  region  :  besides  this,  the  species  has  been 
introduced  into  various  other  parts  of  the  world. 

According  to  Karsch  the  honey-bee  shows  in  Germany  several 
varieties,  all  of  which  belong  to  the  northern  form,  which  may 
be  spoken  of  as  the  A.  domestica  of  Eay ;  the  A.  ligustica  and  A. 
fasciata  form  as  we  have  said  distinct  races,  and  it  is  a  remark- 
able fact  that  these  races  remain  distinct  even  when  imported 
into  other  climates;  though  for  how  long  a  period  of  time  this 
remains  true  there  is  very  little  evidence  to  show.  The  northern 
form,  A.  domestica,  is  now  found  in  very  widely  separated  parts 
of  the  world,  in  some  of  which  it  is  wild  ;  Smith  mentions  it 
as  occurring  in  the  West  India  islands,  throughout  the  North 
American  continent  as  far  south  as  Mexico,  even  in  Central  and 
Southern  Africa,  and  in  Australia  and  New  Zealand.  The  var. 
/it/i/stica  has  been  found  also  at  the  Cape  of  Good  Hope.  The 
other  species  known  of  the  genus  Apis  all  belong  to  the  Old 
World,  so  that  there  is  very  little  doubt  that  A.  mdlijica  is  also 


SOCIALES HONEY-BEE 


69 


C-: 


a  true  native  of  the  eastern  hemisphere,  and  its  original  home 
may  possibly  have  been  not  far  from  the  shores  of  the  eastern 
portion  of  the  Mediterranean  sea.  Seven  or  eight  other  species 
of  Apis  are  known,  all  but  one  of  which  occur  in  Asia,  ex- 
tending as  far  as  Timor  and  Celebes.  The  exceptional  one,  A. 
adansonii,  occurs  in  tropical  Africa  and 
in  Madagascar.  Gerstaecker  thought 
these  species  might  be  reduced  to  four, 
but  Smith's  statement  that  the  males 
and  even  the  workers  show  good  dis- 
tinctive characters  seems  to  be  correct. 
Very  little  is  known  as  to  the  honey- 
bees of  China  and  Japan. 

The  queen-bee  greatly  resembles  the 
worker,  but,  has  the  hind  body  more 
elongated ;  she  can,  however,  always  be 
distinguished  from  the  worker  by  the 
absence  of  the  beautiful  transverse, 
comb-like  series  of  hairs  on  the  inner 
side  of  the  first  joint  of  the  hind  foot, 
the  planta,  as  it  is  called  by  the  bee- 
keeper :  she  has  also  no  wax  plates  and 
differs  in  important  anatomical  peculi- 
arities. The  male  bee  or  drone  is  very 
different,  being  of  much  broader,  more 
robust  build,  and  with  very  large  eyes 
that  quite  meet  in  the  middle  of  the 
upper  part  of  the  head :  he  also  has  the 
hind  leg  differently  shaped.  The  form  of 

this  limb  enables  the  male  of  A.  mellifica  FIG.  25.— Portions  of  hind-feet, 
to  be  distinguished  from  the  correspond- 
ing sex  of  allied  species  of  the  genus. 

We  are  indebted  to  Home  for  some 
particulars  as  to  the  habits  of  A.  dorsata, 
an  allied  East  Indian  species.  He  informs 
us  that  these  bees  greatly  disfigure  buildings,  such  as  the  Taj  Mahal 
at  Agra,  by  attaching  their  pendent  combs  to  the  marble  arches, 
and  are  so  pertinacious  that  it  is  almost  useless  to  destroy  the 
nests.  This  bee  is  said  to  be  so  savage  in  its  disposition  that  it 
cannot  be  domesticated ;  it  attacks  the  sparingly  clad  Hindoos 


1,  of  male,  2,  of  worker,  3, 
<il  queen,  of  the  honey-bee; 
series  on  the  left,  outer 
faces ;  on  the  right,  inner 
faces.  «,  Tip  of  tibia :  b, 
first  joint  ;  c,  second  joint 
of  tarsus. 


70  HYMENOPTERA 


CHAP.    1 


with  great  ferocity  when  they  disturb  its  nest.  Notwithstand- 
ing its  inclination  and  power  to  defend  its  societies  this  Insect 
appears  to  be  destroyed  wholesale.  Colonel  Eamsay  failed  to 
establish  hives  of  it,  because  the  Insects  were  eaten  up  by  lizards. 
The  crested  honey-buzzard  carries  off  large  portions  of  the  comb, 
and  devours  it  on  a  branch  of  some  tree  near  by,  quite  regardless 
of  the  stings  of  the  bees;  while  the  fondness  of  bears  for  the 
honey  of  the  "  Dingar,"  as  this  species  is  called,  is  well  known. 


XOTE  TO  P.  33  :  It  has  just  been  discovered  that  a  most  remarkable 
symbiosis,  with  structural  modification  of  the  bee,  exists  between  the  females 
of  Xylocopa,  of  the  Oriental  sub-genus  Koptorthosoma,  and  certain  Acarids. 
A  special  chamber,  with  a  small  orifice  for  entry,  exists  in  the  abdomen  of 
the  bee,  and  in  this  the  Acari  are  lodged. — See  Perkins,  Ent.  Mag.  xxxv. 
1899,  p.  37. 


NOTE  TO  P.  80  :  referring  to  the  habits  of  social  wasps  in  warm  countries. 
The  anticipation  we  ventured  to  indulge  in  is  shown  to  be  correct  by  the 
recent  observations  of  Yon  Ihering.1  He  states  that  social  wasps  in  Brazil 
may  be  divided  into  two  great  groups  by  their  habits,  viz.  1.  Summer  com- 
munities, lasting  for  one  year,  and  founded  annually  by  fertilised  females 
that  have  hibernated — example,  Polistes  ;  2.  Perennial  communities,  founded 
by  swarms  after  the  fashion  of  bee  colonies — examples,  Polybia,  Chartergus. 

1  Ann.  Not.  Hist.  (6),  xix.  1897,  p.  136. 


XOTE  TO  VOL.  V.  PP.  545,  546  :  The  development  of  Encyrtus  fuscicollis 
has  now  been  studied  by  Marchal,  who  has  discovered  the  existence  of 
embryonic  dissociation.  The  chain  of  embryos  and  the  epithelial  tube  in 
which  they  are  placed,  are  formed  as  follows  :  the  Encyrtus  deposits  an  egg 
in  the  interior  of  the  egg  of  the  Hyponomeuta.  This  does  not  kill  the  egg 
of  the  Lepidopteron,  but  becomes  included  in  the  resulting  caterpillar.  The 
amnion  of  the  Chalcid  egg  lengthens,  and  forms  the  epithelial  tube  ;  while 
the  cells  within  it  become  dissociated  in  such  a  way  as  to  give  rise  to  a 
chain  of  embryos,  instead  of  a  single  embryo. — O.K.  Ac.  Paris,  cxxvi.  1898V 
p.  662,  and  translation  in  Ann.  Nat.  Hist.  (7),  ii.  1898,  p.  28. 


CHAPTER    II 

HYMEXOPTERA  ACULEATA  COXTIXUE1>  -  DIVISION  II.  DIPLOPTERA 
OR  WASPS  -  EUMENIDAE,  SOLITARY  TRUE  WASPS  -  YESPIDAE, 
SOCIAL  WASPS  -  MASARIDAE 

Division  II.  Diploptera  —  Wasps. 

Anterior  wings  longitudinally  plicate  in  repose;  the  pronotum 
extending  back,  so  as  to  form 
on  each  side  an  angle  reposing 
on  the  tea  id  c  i  .;  the  based  seg- 
ments of  the  hind,  bodi/  not 
bearing  nodes  or  scales  ;  the 
hind  tarsi  formed  for  simple 
ti-<ill-ing.  The  species  either 
or  social  in  their 


77..  ...  .  FIG.  26.  —  Upper  aspect  of  pronotum 

habits;  some  existing   rn  three        and  mesonotum  of  a  wasp,  £«»«- 

forms,       males,      females,       and          nes  coarctata.     a,  Angle  of  prono- 
-.  turn  ;  b,  tegula  ;  c,  base  of  wing  ; 

WOT/CeTS.  (^  iriesonotum. 

THIS  division  of  Hymenoptera  includes  the  true  wasps,  but  not 
the  fossorial  wasps.  The  name  applied  to  it  lias  been  suggested 
by  the  fact  that  the  front  wings  become  doubled  in  the  long  direc- 
t  it  in  when  at  rest,  so  as  to  make  them  appear  narrower  than  in 
must  other  Aculeata  (Fig.  27).  This  character  is  unimportant 
in  function  so  far  as  we  know.1  and  it  is  not  quite  constant  in 
the  division,  since  some  of  the  Masaridae  do  not  exhibit  it.  The 
character  reappears  outside  the  Diploptera  in  the  genus  Zei(cc>-- 

—  a  member  of  the  Chalcididae  in  the  parasitic  series  of  Hymen- 
optera —  the  species  of  which  greatly  resemble  wasps  in  coloration. 
A  better  character  is  that  furnished  by  the  well-marked  angle. 

1  Janet  lias  suggested  that  the  folding  is  done  to  keep  the  delicate  hind-margins 
of  the  wings  from  being  frayed. 


HYMENOPTERA 


CHAP. 


formed  by  the  pronotum  on  the  dorsal  part  (Fig.  26).  By  a 
glance  at  this  part  a  Diplopterous  Insect  can  always  be  readily 
distinguished. 

Three  families  are  at  present  distinguished  in  the  Diploptera, 
viz.  Eumeiiidae,  Vespidae  and  Masaridae.  We  anticipate  that 
Eumenidae  and  Vespidae  will  ultimately  be  found  to  constitute 
but  one  family. 

Fam.  1.  Eumenidae — Solitary  True  Wasps. 

Clau's  of  the  feet  toothed  or  Infid  ;  middle  tibiae  with  only  one 
xjn/r  at  tip.  Social  assemblages  are  not  formed,  mid  tin  re  is 
a  n  y/-<//7,r/--rr/.s'/V,  the  duties  of  nest-construction,  etc.,  Icing 
performed  solely  l>y  the  female. 

The  Eumenidae,  or  solitary  wasps,  are  very  little  noticed  by 
the  ordinary  observer,  but  they  are  nevertheless  'more  numerous 

than  the  social  Vespidae,  about  800 
species  being  known.  In  Britain  we 
have  sixteen  species  of  the  solitary,  as 
against  seven  of  the  social  wasps. 
The  Eumenidae  exhibit  a  considerable 
diversity  in  form  and  structure ;  some 
of  them  have  the  pedicel  at  the  base 
of  the  abdomen  very  elongate,  while 
in  others  this  is  so  short  as  to  be 
imperceptible  in  the  ordinary  position 
of  the  body.  A  repetition  of  similar 
differences  of  form  occurs  in  the  social 

wasps,    so    that    notwithstanding    the 
FIG.   27. — Eumenes  flavouicta   9-     TO-  •       i     i  -^      ii  i 

Burma.    The  Wigs  on  the  left  difference  in  habits  there  seenw  to  be 
in  the  position  of  repose,  to  110  satisfactory   way   of  distinguishing 

the  members  of  the  two  families  ex- 
cept by  the  structure  of  the  claws  and  tibial  spurs. 

Fabre  has  sketched  the  habits  of  a  species  of  Eumenes, 
probably  E.  pomiformis.  This  Eumenes  constructs  with  clay  a 
small  vase-like  earthenware  vessel,  in  the  walls  of  which  small 
stones  are  embedded  (like  Fig.  28,  B).  This  it  fills  with  food 
for  the  young.  The  food  consists  of  caterpillars  to  the  number 
of  fourteen  or  sixteen  for  each  nest.  These  caterpillars  art- 
believed  to  be  stung  by  the  parent-wasp  (as  is  the  case  in  the 


II 


DIPLOPTERA WASPS — EUMENIDAE 


73 


fossorial  Hymenoptera),  but  complete  evidence  of  this  does  not 
seem  to  be  extant,  and  if  it  be  so,  the  stinging  does  not 
completely  deprive  the  caterpillars  of  the  capacity  of  movement, 
for  they  possess  the  power  of  using  their  mandibles  and  of 
making  strokes,  or  kicking  with  the  posterior  part  of  the  body. 
It  is  clear  that  if  the  delicate  egg  of  the  Eumenes  or  the  deli- 
cate larva  that  issues  from  it  were  placed  in  the  midst  of  a 
mass  of  this  kind,  it  would  probably 
suffer  destruction  ;  therefore,  to 
prevent  this,  the  egg  is  not  placed 
among  the  caterpillars,  but  is  sus- 
pended from  the  dome  covering 
the  nest  by  a  delicate  thread 
rivalling  in  fineness  the  web  of  the 
spider,  and  being  above  the  mass 
of  food  it  is  safe.  When  the 
young  larva  leaves  the  egg  it  still 
makes  use  of  the  shell  as  its  habit- 
ation, and  eats  its  first  meals 
from  the  vantage-point  of  this 
suspension;  although  the  mass  of  FIG.  28.— Nidification  of  solitary  wasps: 


the  food  grows  less  by  consumption,        secticm  tlnou"h  neg>  *'  °f 

o  J_  in'i-its    reniformis ;   B,    of   Eumenes 

the  little    larva    is    Still    enabled    to          arbiistonnn.     «,  The  suspended  egg 

reach  it  by  the  fact  that  the  egg-        »,',£.  ^,"^t?™ 
shell  splits  up  to  a  sort  of  ribbon, 

and  thus  adds  to  the  length  of  the  suspensory  thread,  of  which  it 
is  the  terminal  portion.  Finally  the  heap  of  caterpillars  shrinks 
so  much  that  it  cannot  be  reached  by  the  larva  even  with  the 
aid  of  the  augmented  length  of  the  suspensory  thread  ;  by  this 
time,  however,  the  little  creature  has  so  much  increased  in  size 
and  strength  that  it  is  able  to  take  its  place  amongst  the  food 
without  danger  of  being  crushed  by  the  mass,  and  it  afterwards 
completes  its  metamorphosis  in  the  usual  manner. 

It  is  known  that  other  species  of  Eumenes  construct  vase- 
like  nests  ;  E.  unguiculata,  however,  according  to  an  imperfect 
account  given  by  Perris,  makes  with  earth  a  closed  nest  of 
irregular  shape,  containing  three  cells  in  one  mass.  The  saliva 
of  these  builders  has  the  power  of  acting  as  a  cement,  and  of 
forming  with  the  clay  a  very  impenetrable  material.  One 
species,  E.  coarctata,  L.  of  this  genus  occurs  in  Britain.  The  clay 


74 


HYMENOPTERA 


CHAP. 


to  wood  :  B, 


nests  (Fig.  29)  of  this  Insect  are  often  attached  to  the  twigs  of 
shrubs,  while  those  of  the  two  species  previously  mentioned  are 

usually  placed  on  objects  that  offer  a 
large  surface  for  fixing  the  foundations 
to,  such  as  walls.  According  to  Goureau 
the  larva  of  this  species  forms  in  one 
corner  of  its  little  abode,  separated  by  a 
partition,  a  sort  of  dust-heap  in  which 
it  accumulates  the  various  debris  re- 
sulting from  the  consumption  of  its 
stores. 

Eumenes  ccniica,  according  to  Home, 
constructs  in  Hindostan  clay-nests  with 
very  delicate  walls.      This  species    pro- 
visions  its  nest  with  ten  or  Uvelve  green 
de-  caterpillars  ;    on    one    occasion    this    ob- 
^rver   took'  from   one    cell   eight   green 
tion    of  the   cell.     (After   caterpillars  and  one  black.      It  is  much 

Andre.)  .,  •  •  , 

attacked     by     parasites     owing,     it      is 

thought,  to  the  delicacy  of  the  walls  of  the  cells,  which  are 
easily  pierced  ;  from  one  group  of  five  cells  two  specimens  only 
of  the  Eumenes  were  reared. 

()<li/nerus,  with  numerous  sub-genera,  the  names  of  which 
are  often  used  as  those  of  distinct  genera,  includes  the  larger 
part  of  the  solitary  wasps  ;  it  is  very  widely  distributed  over  the 
earth,  and  is  represented  by  many  peculiar  species  even  in  the 
isolated  Archipelago  of  Hawaii  ;  in  Britain  we  have  about  fifteen 
species  of  the  genus.  The  Odynerus  are  less  accomplished 
architects  than  the  species  of  Eumenes,  and  usually  play  the 
more  humble  parts  of  adapters  and  repairers  ;  they  live  either  in 
holes  in  walls,  or  in  posts  or  other  woodwork,  or  in  burrows  in 
the  earth,  or  in  stems  of  plants.  Several  species  of  the  sub- 
genus  H<>/i/<ij>/rs  have  the  remarkable  habit  of  constructing 
burrows  in  sandy  ground,  and  forming  at  their  entry  a  curvate, 
freely  projecting  tube  placed  at  right  angles  to  the  main  bur- 
row, and  formed  of  the  grains  of  sand  brought  out  by  the 
Insect  during  excavation  and  cemented  together.  The  habits  of 
one  such  species  were  described  by  Eeaumur,  of  another  by 
Dufour  ;  and  recently  Fabre  has  added  to  the  accounts  of  these 
naturalists  some  important  information  drawn  from  his  own 


II 


WASPS — EUMENIDAE 


75 


observations  on  0.  reniformis.  This  Insect  provisions  its  cell 
with  small  caterpillars  to  the  number  of  twenty  or  upwards  (Fig. 
28,  A.)  The  egg  is  deposited  before  the  nest  is  stocked  with  food ; 
it  is  suspended  in  such  a  manner  that  the  suspensory  thread 
allows  the  egg  to  reach  well  down  towards  the  bottom  of  the 
cell.  The  caterpillars  placed  as  food  in  the  nest  are  all  curled 
up,  each  forming  a  ring  approximately  adapted  to  the  calibre  of 
the  cell.  Fabre  believes  these  caterpillars  to  be  partly  stupefied 
by  stinging,  but  the  act  has  not  been  observed  either  by  himself, 
Beaumur,  or  Dufour.  The  first  caterpillar  is  eaten  by  the  wasp- 
larva  from  its  point  of  suspension  ;  after  this  first  meal  has  been 
made  the  larva  is  supposed  to  undergo  a  change  of  skin  ;  it  then 


FIG.  30. — Odynerus  antilope  ?.     Britain. 

abandons  the  assistance  of  the  suspensory  thread,  taking  up  a 
position  in  the  vacant  chamber  at  the  end  of  the  cell  and  draw- 
ing the  caterpillars  to  itself  one  by  one.  This  arrangement 
permits  the  caterpillars  to  be  consumed  in  the  order  in  which 
they  were  placed  in  the  cell,  so  that  the  one  that  is  weakest  on 
account  of  its  longer  period  of  starvation  is  first  devoured. 
Fa,bre  thinks  all  the  above  points  are  essential  to  the  successful 
development  of  this  wasp-larva,  the  suspension  protecting  the  egg 
and  the  young  larva  from  destruction  by  pressure  or  movement 
of  the  caterpillars,  while  the  position  of  the  larva  when  it  leaves 
the  thread  and  takes  its  place  on  the  floor  of  the  cell  ensures  its 
consuming  the  food  in  the  order  of  introduction  ;  besides  this  the 
caterpillars  used  are  of  a  proper  size  and  of  a  species  the 


76  IIVMENOPTERA 


CHAP. 


individuals  of  which  have  the  habit  of  rolling  themselves  up  in  a 
ring  ;  while,  as  the  calibre  of  the  tube  is  but  small,  they  are 
unable  to  straighten  themselves  and  move  about,  so  that  their 
consumption  in  proper  order  is  assured.  Some  interesting 
points  in  the  habits  of  an  allied  species,  0.  (Pteroclieilus)  spinipes 
have  been  observed  by  Verhoeff;  the  facts  as  regards  the  con- 
struction and  provisioning  of  the  cell  are  almost  the  same  as  in 
0.  reniformis.  The  species  of  Odynerus  are  very  subject  to  the 
attacks  of  parasites,  and  are,  it  is  well  known,  destroyed  to  an 
enormous  extent  by  Chrysididae.  Verhoeff  says  that  the  wasp 
in  question  supplied  food  much  infested  by  entoparasites  ;  further, 
that  a  fly,  Argi/romoeba  sinuata,  takes  advantage  of  the  habit  of 
the  Odyne.rtis  of  leaving  its  nest  open  during  the  process  of  pro- 
visioning, and  deposits  also  an  egg  in  the  nest  ;  the  Odyncrus 
seems,  however,  to  have  no  power  of  discovering  the  fact,  or  more 
probably  has  no  knowledge  of  its  meaning,  and  so  concludes  the 
work  of  closing  the  cell  in  the  usual  way ;  the  egg  of  the 
Ariiyromoelxi  hatches,  and  the  maggot  produced  feeds  on  the 
caterpillars  the  wasp  intended  for  its  own  offspring.  Yerhoeff 
observed  that  the  egg  of  the  wasp-larva  is  destroyed,  but  he  does 
not  know  whether  this  was  done  by  the  mother  Argyromoeba  or 
by  the  larva  hatched  from  her  egg.  Fabre's  observations  on 
allied  species  of  Diptera  render  it,  however,  highly  probable  that 
the  destruction  is  effected  by  the  young  fly-larva  and  not  by 
the  mother-fly. 

Mr.  E,  0.  L.  Perkins  once  observed  several  individuals  of  our 
British  0.  callosus  forming  their  nests  in  a  clay  bank,  and  pro- 
visioning them  with  larvae,  nearly  all  of  which  were  parasitised, 
and  that  to  such  an  extent  as  to  be  evident  both  to  the  eye  and 
the  touch.  In  a  few  days  after  the  wasps'  eggs  were  laid,  swarms 
of  the  minute  parasites  emerged  and  left  no  food  for  the  Odynci'n*. 
Curiously,  as  it  would  seem,  certain  of  the  parasitised  and  stored- 
up  larvae  attempted  (as  parasitised  larvae  not  infrequently  do), 
to  pupate.  From  which,  as  Mr.  Perkins  remarks,  we  may  infer 
that  (owing  to  distortion)  the  act  of  paralysing  by  the  wasp  had 
been  ineffectual.  Mr.  Perkins  has  also  observed  that  some  of  the 
numerous  species  of  Hawaiian  Odynerus  make  a  single  mud-cell, 
very  like  the  pot  of  an  Eumenes,  but  cylindrical  instead  of 
spherical.  This  little  vessel. is  often  placed  in  a,  leaf  that  a 
spider  curls  up  ;  young  molluscs  of  the  genus  Achatinella  also 


ii  WASPS EUMENIDAE  77 

avail  themselves  of  this  shelter,  so  that  a  curious  colony  is  formed, 
consisting  of  the  Odynerus  in  its  pot,  of  masses  of  the  young 
spiders,  and  of  the  little  molluscs. 

Home  has  recorded  that  the  East  Indian  0,  puncttim  is  fond 
of  availing  itself  of  holes  in  door-posts  where  large  screws  have 
heen ;  after  the  hole  has  been  filled  with  provisions,  the  orifice 
is  covered  over  level  with  the  surface  of  the  wood  so  that  it 
eludes  human  observation.  It  is  nevertheless  discovered  by  an 
Ichneumon-fly  which  pierces  the  covering  with  its  ovipositor  and 
deposits  an  egg  within. 

The  genus  Abispa  is  peculiar  to  Australia  and  includes  some 
very  fine  solitary  wasps,  having  somewhat  the  appearance  of  very 
large  Odynerus  :  these  Insects  construct  a  beautiful  nest  with  a 
projecting  funnel-shaped  entrance,  and  of  so  large  a  size  that  it 
might  pass  for  the  habitation  of  a  colony  of  social  wasps ;  it 
appears,  however,  that  this  large  nest  is  really  formed  by  a  single 
female. 

The  species  of  the  genus  Rhygchium  are  also  of  insecticide 
habits,  and  appear  to  prefer  the  stems  of  pithy  plants  as  the 
nidus  for  the  development  of  the  generation  that  is  to  follow 
them.  Lichtenstein  says  that  a  female  of  the  European  R. 
oculatum  forms  fifteen  to  twenty  cells  in  such  a  situation,  and 
destroys  150  to  200  caterpillars,  and  he  suggests  that,  as  it  is 
easy  to  encourage  these  wasps  to  nest  in  a  suitable  spot,  we  should 
utilise  them  to  free  our  gardens  from  caterpillars,  as  we  do  cats 
to  clear  the  mice  from  our  apartments. 

The  East  Indian  R.  carnaticum  seems  to  have  very  similar 
habits  to  its  European  congener,  adapting  for  its  use  the  hollow 
stems  of  bamboos.  Home  has  recorded  a  case  in  which  a  female 
of  this  species  took  possession  of  a  stem  in  which  a  bee,  Megachile 
lanata,  had  already  constructed  two  cells ;  it  first  formed  a  parti- 
tion of  mud  over  the  spot  occupied  by  the  bee,  this  partition  being 
similar  to  that  which  it  makes  use  of  for  separating  the  spaces 
intended  for  its  own  young.  This  species  stores  caterpillars  for 
the  benefit  of  its  larvae,  and  this  is  also  the  case  with  another 
Eastern  species,  E.  nitidulum.  This  latter  Insect,  however,  does 
not  nidificate  in  the  stems  of  plants,  but  constructs  clay  cells 
similar  to  those  of  Uumenes,  and  fixes  them  firmly  to  wood. 
Rhygchium  Innineum  is  said  by  Sir  Bicharcl  Owen  to  obliterate 
hieroglyphic  inscriptions  in  Egypt  by  its  habit  of  building  mud 


78  11YMF,\OPTKRA  CIIAI-. 


nests  amongst  them.  An  individual  ol'  this  wasp  was  found 
by  Pr.  Birch  when  unrolling  a  mummy — "Then1  being  every 
reason  to  believe  that  the  In  see  I  hail  remained  in  the  position  in 
which  it  was  found  ever  sinee  tin1  last  rites  were  paid  to  the 
aneieiit  Egyptian." 

Fam.  2.  Vespidae — Social  Wasps. 

Claws  of  the  feet  simple,  neither  toothed  nor  bijid,  middle  tibiae 
•with  tico  spurs  (ft  the  tip.  Insects  living  in  societies,  for/// - 
inif  a  common  dicellitii/  of  a  papery  or  card-like  material  ; 
each  generation  consists  of  males  and  females  and  of  workers 
—imperfect  females — that  assist  the  reproductive  female  by 
carrying  on  the  -industrial  occupations. 

The  anterior  wing  possesses  four  submarginal  eells,  as  in  the 
Eumenidae.  The  attention  of  entomologists  has  been  more 
directed  to  the  habits  and  architecture  than  to  the  taxonomy  of 
these  Insects,  so  that  the  external  structure  of  the  Insects  them- 
selves has  not  been  so  minutely  or  extensively  scrutinised  as  is 
desirable;  de  Saussure,  the  most  important  authority,  buses  his 
classification  of  the  Insects  themselves  on  the  nature  of  the  nests 
they  form.  These  habitations  consist  of  an  envelope,  protecting 
cells  similar  in  form  to  the  comb  of  the  honey-bee,  but  there  is 
this  important  difference  between  the  two,  that  while  the  bee 
forms  its  comb  of  wax  that  it  secretes,  the  wasps  make  use  of 
paper  or  card  that  they  form  from  fragments  of  vegetable  tissue, 
—more,  particularly  woodv  fibre — amalgamated  by  means  of 

IV  O  J 

cement  secreted  by  glands ;  the  vegetable  fragments  are  obtained 
by  means  of  the  mandibles,  the  front  legs  playing  a  much  less 
important  part  in  the  economy  of  the  Vespidte  than  they  do  in 
that  of  the  bees  and  fossorial  Hymenoptera, 

In  most  of  the  nests  of  Yespida?  the  comb  is  placed  in  stages 
or  stories  one  above  the  other,  and  separated  by  an  intervening 
space,  but  in  many  cases  there  is  only  one  mass  of  comb.  It  is  the 
rule  that,  when  the  eells  of  the  comb  are  only  partially  formed,  eggs 
are  deposited  in  them,  and  that  the  larva  resulting  from  the  egg 
is  fed  and  tended  by  the  mother,  or  by  her  assistants,  the  workers  ; 
as  the  larvae  grow,  the  cells  are  increased  in  correspondence  with 
the  size  of  the  larva  :  the  subsequent  metamorphosis  to  pupa  and 
imauo  taking  place  in  the  cells  after  thev  have  been  entirely 

O        -L  v  v 


n 


SOCIAL  WASI'S YKSPIDAK 


79 


a 


cjo-e<l.  Th'-  food  supplied  is  of  a  v./ried  nature  according  to 
til--  species,  l-'-in-j  either  ;minjal  or  vegetable,  or  both. 

Although  the  nests  of  the  social  wasps  are  very  elaborate  con- 
structions, y«:t  they  n-rve  the  purposes  of  the  Insects  for  only  a 
sinide  season.  This,  is  '•«-)-t.;i.iu]y  t:be  case  in  our  own  country. 
H' I--  e;i<-h  nest  i.-:  e<,ii,]j|i.|jcp<|  l.y  a  single  female  or  queen;  she 

irst  pei Toi ju-   unaided  all  the  duties  for  the  inauguration  of 

FIG.  31. — Section  of  the 
subterranean  nest  of  the 
common  wasp,  TV/." 
gerrnanica,  in  posit 
(After  Janet.)  «,  One 
of  the  chambers  of  an 
ant's  nest,  Losing fiavus, 
placed  above  the  wasps' 
nest ;  b,  root  to  which 
the  first  attachment  of 
the  nest  was  made  ;  c, 
secondary  attachments ; 
d,  the  first-made  attach- 
ment ;  e,  a  flint  within 
the  envelopes  of  the 
nest ;  /,the  chief  suspen- 
sory pillar  of  the  second 
layer  of  comb  ;  y,  lateral 
galleries  ;  h,  one  of  the 
secondary  pillars  of 
suspension  between  two 
layers  of  comb ;  i,  the 
layers  of  wasp  -  paper 
forming  the  envelope  of 
nest  ;  j,  vacant  space 
round  the  nest ;  k.  flints 
that  fell  to  the  bottom 
during  the  work  of  ex- 
cavation ;  I,  numerous 
larvae*  of  any,  Pegr/myia 

placed  vertically  in  ground  beneath  the  nest ;  m1  to  m1,  the  layers  of  comb, 
in  in-  th':  cells  are  indicated  ,  in  ms  (above  the  main  figure;  the  arrangement  of  the 
three  cells  forming  the  commencement  of  the  new  layer  of  comb,  m7,  is  shown  ;  n, 
galler  irom  surface  ;  o,  burrow  of  a  mole  ;  x>>  interval  of  90  mm.  between  top 

of  uest  and  surface  ;  ^>  height  of  tne  nest,  163  mm. 

the    '-olouy;  she  lays   the  foundation  of  the   cells,  deposits  the 

_ .-  in  them,  feeds  the  young,  arid  thus  rears  a  brood  of  work 
that  ;it  on'-'-  ;i-.-ist  her,  and  for  the  future  relieve  her  of  a  con- 
-i'l'-mljle  portion  of  her  former  occupations;  the  nest  is  by  them 
;nl<l'"l  to  and  increased,  till  the  cold  weather  of  the  autumn  is  at 
luind:  at  tliis  time  many  males  and  females  are  produced;  the 
cold  weather  either  destroys  the  inhabitants  of  the  nest,  or  re- 
duces their  vitality  so  that  it  is  impossible  for  them  to  pursue 
successfully  the  avocations  necessary  for  their  subsistence,  and 


SO  HYMENOPTERA 


CHAP. 


they  succumb  to  adversity.  The  young  females,  however,  hiber- 
nate, and  each  one  that  lives  through  the  winter  is  the  potential 
founder  of  a  new  nest  in  the  way  we  have  already  described.  It 
might  be  supposed  that  in  tropical  countries  where  no  cold 
season  occurs  the  phenomena  would  be  different,  that  the  colonies 
would  be  permanent,  and  that  the  nests  would  be  inhabited  until 
they  were  worn  out.  De  Saussure,  however,  informs  us  that  this 
is  not  the  case,  but  that  in  the  tropics  also  the  colonies  die  off 
annually.  "  The  nests  are  abandoned,"  he  says,  "  without  it  being- 
possible  to  discover  the  reason,  for  apparently  neither  diminution 
of  temperature  nor  scarcity  of  food  cause  them  (the  Insects)  to 
suffer.  One  is  tempted  to  suppose  that  the  death  of  the  Insects 
is  the  result  of  a  physiological  necessity." 

Nests  of  Social  Wasps. — In  Europe  wasps'  nests  disappear 
very  soon  after  they  are  deserted.  As  it  would  appear  from  de 
Saussure's  conclusions  that  in  the  tropics  as  well  as  in  the  temperate 
regions  the  rule  is  that  the  colonies  endure  only  a  portion  of  one 
year,  and  that  a  new  nest  is  commenced  by  a  single  founder  once 
in  twelve  months,  it  is  a  somewhat  remarkable  fact  that  some 
tropical  wasp-nests  are  much  more  durable  than  the  lives  of  the 
inhabitants  require,  so  that  solidly  constructed  nests  are  often 
found  hanging  to  the  trees  long  after  they  have  been  deserted, 
and  are  sometimes  overgrown  with  moss.  Cuming  has  recorded 
the  fact  that  he  found  in.  South  America  an  old  wasp-nest  that  had 
been  taken  possession  of  by  swallows.  "\Ve  do  not  assign,  how- 
ever, much  importance  to  the  views  of  de  Saussure,  because  we 
may  anticipate  that  enquiry  will  reveal  much  variety  in  the 
habits  of  tropical  and  sub-tropical  wasps.  It  is  known  that 
species  exist  that  store  up  honey,  after  the  fashion  of  bees,  and 
von  Ihering  has  recently  shown  l  that  in  Brazil,  species  of  several 
genera  form  new  colonies  by  swarming,  after  the  manner  of  bees. 
So  that  it  is  possible  that  certain  colonies  may  remain  for  a  long 
period  in  the  same  nest. 

Much  more  variety  exists  in  wasps'  nests  than  would  be  sup- 
posed probable ;  those  formed  by  some  of  the  tropical  species  of 
Vespidae  are  enveloped  in  so  solid  and  beautifully  constructed  an 
envelope  of  papier-mache,  that  they  resist  with  complete  success 
the  torrential  rains  of  the  tropics  ;  while  some  of  those  found  in 
our  own  country  are  made  of  extremely  soft  and  delicate  paper, 

1  ZuoL  ^/f~.  xix.  1896,  p.  449.     See  also  note,  antca,  p.  70. 


II 


VESPIDAE — WASPS'  NESTS 


8l 


which  is  probably  chiefly  glandular  products.  Our  British 
Yespidae  number  only  eight  species,  all  belonging  to  the  one 
genus  Vespa,  and  yet  they  exhibit  three  different  modes  of 
nidification.  Vespa  vulgaris,  V.  germanica  and  V.  rvfa  form 
subterranean  nests,  while  V.  arborea,  V.  sylvestris  and  V.  norvcyica 
suspend  their  habitations  from  the  branches  of  trees,  bushes,  or 
strong  annual  plants.  Vespa  crabro,  the  hornet,  usually  adopts 
an  intermediate  course,  forming  its  nest  above  ground,  but  in  a 
spot  where  it  is  protected  and  concealed. 
The  favourite  habitat  of  this  formidable 
Insect  is  the  interior  of  an  old  tree,  but 
the  hornet  will  sometimes  avail  itself  of 
the  protection  of  a  thatched  roof.  Both 
it  and  other  arboreal  species  are  said, 
however,  to  occasionally  make  subter- 
ranean nests.  It  is  ascertained  that 
V.  austriaca,  the  eighth  species,  is  an 
inquiline. 

De  Saussure,1  the  monographer  of  the 
social  wasps,  classifies  them  according  to 
the  architecture  of  their  nests.  He  estab- 
lishes three  groups:  (1)  Stelocyttares,  in 
which  the  layers  of  comb  are  not  con- 
nected with  the  envelope,  but  are  sup- 
ported by  pillars  made  by  the  wasps  (Fig. 
31);  (2)  Poecilocyttares,  an  unsatisfac- 
tory group  of  which  the  chief  character- 
istics appear  to  be  that  the  nest  is  always 
covered  by  an  envelope,  and  the  comb  is 

supported  by  an  object  such  as  the  branch 

P  -,  i  •   i     v-i  i  FIG.  32.— Nest  of  (?)  PolyUa 

ot  a  tree,  round,  or  on,  which  the  envelope        sp_    The  enve]ope  partly 

is  placed  (Fig.  32) ;  (3)  Phragmocyttares,        cut   °Pe"  ;  °.  entrance. 

.  .    ,     . ,  (After  de  Saussure.) 

in  winch  the  layers  ot  comb  are  supported, 

in  part  or  entirely,  by  the  envelope  of  the  nest,  communication 
being  effected  by  a  hole  in  each  layer  of  the  comb  (Fig.  33). 
de  Saussure's  classification  is  far  from  satisfactory.  There  are 
many  social  wasps  that  construct  nests  destitute  of  any  proper 
envelope  ;  as  an  example  of  this,  we  may  mention  the  species  of 

1  Monographic  des  gutpes  societies,  Geneva,  1853-1858,   pp.   cc.  and  356,  plates 
i.-xxxvii. 

VOL.  VI  G 


O 


82  HVMEXOPTERA 


CHAP. 


the  abundant  genus  Polistes  ;  these  Insects  make  hexagonal  cells, 
of  paper -like  material,  forming  an  irregular  comb,  or  mass, 
attached  to  bushes  by  a  stalk  near  its  centre ;  these  nests  are 
placed  so  that  the  mouths  of  the  open  cells  look  downwards. 
The  species  of  Ischnogaster  (Fig.  34)  make  layers  of  comb,  con- 
nected by  a  pedicel,  but  without  any  envelope ;  these  Insects 
form  a  section  of  Stelocyttares  called  Gymuodomes. 

Most  of  the  nests  of  the  Poecilocyttares  have  only  a  single 
layer  of  cornb.  The  wasps  of  the  genera  Synoeca  and  Polybia 
have  the  habit  of  spreading  a  layer  of  cells  on  a  leaf,  or  on  the 
bark  of  a  tree,  and  of  covering  this  with  an  envelope  that  is 
pierced  by  a  single  orifice  only,  but  that  does  not  rest  on  the 
cells,  and  so  allows  circulation  of  the  Insects  between  the  cells 
and  the  envelope.  This  appears  to  be  the  arrangement  in  a 
nest  of  Synoeca  cyanea  preserved  in  the  British  Museum  ;  in 
this  construction  a  large  layer  of  cells  is  moulded  on  the  branch 
of  a  tree,  whose  contour,  for  a  length  of  two  or  three  feet,  it  con- 
sequently follows ;  while  outside  the  mass  there  is  placed  a  con- 
tinuous envelope,  leaving  a  considerable  distance  between  it  and 
the  cells. 

It  would  be  impossible  in  the  space  at  our  disposal  to  give  a 
satisfactory  account  of  all  the  forms  of  wasp-nests,  and  we  must 
therefore  refer  the  student  to  de  Saussure's  work,  confining 
ourselves  to  a  brief  notice  of  some  specially  interesting  forms. 
The  habitation  of  the  Brazilian  Polylna  (Myrapetra)  scutellaris 
is  a  very  solid,  closed  structure,  covered  externally  with  rough 
knobs  or  angular  projections.  Although  of  very  large  size- 
it  may  be  upwards  of  two  feet  in  length — it  is  suspended  from  a 
branch,  and  has  but  one  orifice  ;  the  arrangement  of  the  combs 
in  the  interior  is  that  of  the  Phragrnocyttares,  they  being 
firmly  attached  to  the  outer  envelope,  and  so  placed  as  to  form  a 
curved  surface,  the  convexity  of  which  is  downwards  :  the  number 
of  wasps  in  a  well-developed  nest  of  this  kind  must  be  very  great. 
This  species  is  said  to  be  a  honey-gathering  wasp. 

One  of  the  best  known  of  the  South  American  wasps'  nests  is  the 
construction  (Fig.  33)  of  Chartergus  chartarius ;  these  nests  are  so 
regularly  shaped,  and  formed  of  papier-mache  so  compact  and  solid, 
as  to  look  like  stone  :  this  edifice  is  attached  in  a  very  firm  manner 
to  the  branch  of  a  tree,  and  has  a  single  portal  of  entry  beneath  ; 
its  interior  arrangement  is  much  like  that  of  Myrapetra  scutellaris. 


II 


VESPIDAE WASPS'  XESTS 


A  very  remarkable  wasp's  nest  is  preserved  in  the  British 
Museum  of  Xatural  History ;  it  is  considered  to  be  the  work  of 
M~"/ttez"./ni"  ili  inidiata  Sauss.  an  Eumenid 
wasp  ;  it  is  a  large  mass  of  cells  encircling 
the  branch  of  a  tree,  which  therefore  pro- 
jects somewhat  after  the  manner  of  an 
axle  through  the  middle :  the  cells  are 
very  numerous,  and  are  quite  as  regular 
as  those  of  the  most  perfect  of  the  combs 
of  bees :  the  mass  is  covered  with  a  very 
thick  layer  of  paper,  the  nest  having 
somewhat  the  external  appearance  of  half 
a  cocoa-nut  of  twice  the  usual  size. 

Apoica  pallida,  a  South  American 
Insect,  forms  a  nest  in  a  somewhat  similar 
manner  to  Polistes,  but  it  is  covered  on 
its  outer  aspect  by  a  beautiful  paper  FIG.  33.— Section  of  nest  of 

i  .  ,,  ,1  in  i  Chartergus      chartarius. 

skill,    SO    that    the     nest    looks     Somewhat          South  America,  o.  Entrance. 

like    a    toadstool   of   large   size   attached        (After  de  Saussure.) 
to  the  branch  of  a  tree. 

The  nests  of  the  Insects  of  the  genus  Polylna — which  we 
have  already  mentioned  as  located  by  de  Saussure  in  his  unsatis- 
factory group  Poecilocyttares — usually  have  somewhat  the  form 
and  size  of  pears  or  apples  suspended  to  twigs  of  trees  or  bushes ; 
these  little  habitations  consist  of  masses  of  cells,  wrapped  in 
wasp-paper,  in  which  there  are  one  or  more  orifices  for  ingress  and 
egress.  Smith  says  that  the  combs  in  the  nest  of  P.  pygmaea 
are  of  the  most  exquisite  construction,  and  that  it  i^s  by  no 
means  an  uncommon  circumstance  to  find  the  outer  envelope  of 
the  nest  ornamented  with  patches  of  delicate  hexagonal  .tracery. 
This  nest  is  about  the  size  of  an  orange. 

We  have  already  noticed  the  variety  of  nests  formed  by  our 
British  species  of  the  genus  Vespa  ;  in  other  parts  of  the  world 
the  edifices  formed  by  species  of  Vespa  attain  a  very  large  size. 
V.  crabroniformis  in  China,  and  V.  velutina  in  India,  make  nests 
several  feet  or  even  yards  in  length,  inhabited  by  an  enormous 
number  of  individuals ;  they  are  apparently  constructed  of  a 
material  like  brittle  paper,  and  are  arranged  much  like  the 
nests  of  our  British  hornet,  V.  cralro.  Vespa  orientalis  mixes  a 
considerable  quantity  of  earth  with  the  paper  it  uses  for  its 


84  HYMENOPTERA 


CHAP. 


constructive  efforts.  In  the  British  Museum  collection  there  is 
a  nest  said  to  be  that  of  the  Japanese  hornet,  V.  japonica.  This 
is  completely  covered  by  a  paper  envelope,  and  has  apparently" 
only  a  single  small  orifice  for  ingress  and  egress.  In  the  same 
collection  there  is  a  nest  from  Bahia  (believed  to  be  that  of 
a  social  wasp,  though  of  what  species  is  unknown),  the  outer 
wall  of  which  is  apparently  formed  entirely  of  earth,  and  is  a 
quarter  or  half  an  inch  thick  :  the  comb  inside  appears  also  to 
be  formed  of  clay,  the  whole  forming  an  elaborate  construction 
in  pottery.  One  is  tempted  to  believe  it  may  prove  to  be  the 
production  of  a  social  Eumenid. 

Habits  of  Social  Wasps. — We  have  already  briefly  noticed 
the  way  in  which  a  colony  of  wasps  is  founded,  but  some  further 
particulars  as  to  the  mode  in  which  the  society  is  increased  and 
developed  may  be  mentioned.  The  queen-wasp  makes  at  first  only 
a  very  small  group  of  three  or  four  incomplete  cells  ;  each  cell  is  at 
first  circular,  or  nearly  so,  and  moreover  is  of  smaller  diameter  than 
it  will  afterwards  be.  In  each  of  the  first  three  or  four  incomplete 
cells  an  egg  is  laid,  and  more  cells  are  commenced  ;  but  as  the 
eggs  soon  hatch  and  produce  larvae  that  grow  rapidly,  the  labours 
of  the  queen-wasp  are  chiefly  directed  to  feeding  the  young.  At 
first  she  supplies  them  with  saccharine  matter,  which  she  pro- 
cures from  flowers  or  fruits,  but  soon  gives  them  a  stronger  diet 
of  insect  meat.  This  is  procured  by  chasing  living  Insects  of 
various  kinds.  Some  species  of  wasps  prefer  particular  kinds  of 
Insects,  and  the  hornet  is  said  to  be  very  fond  of  the  honey-bee,  but 
as  a  rule  Diptera  are  the  prey  selected.  When  an  Insect  has  been 
secured,  the  hard  and  innutritions  parts  are  bitten  off,  and  the 
succulent  parts,  more  especially  the  thorax  which  contains  chiefly 
muscular  tissue,  are  reduced  to  a  pulp  by  means  of  the  mandibles; 
this  is  offered  to  the  larvae,  which  are  said  to  stretch  out  their 
heads  to  the  mother  to  receive  the  food,  after  the  manner  of  nest- 
ling birds.  When  a  larva  is  full  grown  it  spins  a  cocoon  in  the 
cell  and  changes  to  a  pupa.  It  is  said  by  some  entomologists 
that  the  queen-wasp  closes  the  cell  for  the  purpose  of  the  larval 
metamorphosis;  but  -this  is  contradicted  by  others,  and  is  prob- 
ably erroneous.  In  about  a  month,  or  a  little  less,  from  the 
time  of  deposition  of  the  egg,  the  perfect  Insect  is  ready  for  issue, 
and  almost  immediately  after  leaving  its  cell  it  assists  in  the 
work  that  is  going  on  for  the  development  of  the  society.  The 


II 


VESPIDAE SOCIAL  WASPS HABITS  85 


Insects  produced  at  this  early  period  of  the  colony  are  exclusively 
workers,  i.e.  imperfect  females.  They  relieve  the  queen  of 
the  task  of  supplying  the  larvae  with  food,  and  she  henceforth 
remains  within  the  nest,  being,  it  is  said,  herself  fed  by  her 
workers  ;  the  society  now  rapidly  increases  in  numbers,  and  fresh 
combs  are  formed,  the  tipper  layer  being  always  the  oldest. 
About  the  month  of  August,  cells  of  larger  size  than  those  that 
have  previously  been  constructed  are  formed,  and  in  these  males 
and  perfect  females  are  produced ;  in  a  few  weeks  after  this  the 
colony  languishes  and  becomes  extinct.  When  it  is  no  longer 
possible  for  the  enfeebled  wasps  to  carry  out  their  tasks  of  feeding 
the  brood,  they  drag  the  larvae  out  of  the  cells  and  destroy  them. 
An  uncertain  number  of  queen-wasps  seek  protected  nooks  in 
which  to  pass  the  winter,  and  each  of  these  queens  may  be  the 
founder  of  a  nest  in  the  ensuing  spring.  It  should  be  remarked 
that  de  Saussure  states  that  all  the  intermediate  grades  between 
perfect  and  imperfect  females  exist,  and  Marchal's  recent  observa- 
tions confirm  this.  There  is  in  fact  no  line  of  demarcation 
between  worker  and  queen  in  the  wasps  as  there  is  in  the  honey- 
bee. Von  Siebold  long  since  drew  attention  to  the  existence  of 
parthenogenesis  in  certain  species  of  wasps,  and  it  appears  prob- 
able that  it  is  of  common  occurrence. 

Our  knowledge  of  the  social  life  of  European  wasps  has 
recently  been  much  increased  by  the  observations  of  twTo  French 
naturalists,  P.  Marchal  and  C.  Janet.  The  latter  has  given 
an  elaborate  history  of  a  nest  of  the  hornet,  showing  the  rate 
and  variations  of  increase  in  numbers.  His  observations  on  this 
and  other  species  indicate  that  warmth  is  of  the  utmost  im- 
portance to  wasps  ;  the  Insects  themselves  create  a  consider- 
able amount  of  heat,  so  that  the  temperature  of  their  abodes  is 
much  greater  than  that  of  the  air.  He  considers  that  in  Europe 
an  elevated  temperature  is  essential  for  the  development  of  the 
individual,1  and  that  the  chief  object  of  the  various  wrappers  of 
paper  with  which  the  Insects  surround  their  nests  is  to  keep 
up  this  high  temperature.  These  envelopes  give  a  great  deal 
of  trouble  to  the  Insects,  for  they  have  to  be  repeatedly 

1  Hence  probably  the  great  difference  in  the  abundance  of  wasps  in  different 
years  :  if  a  period  of  cold  weather  occur  during  the  early  stages  of  formation  of  a 
wasp  family,  operations  are  suspended  and  growth  delayed  ;  or  death  may  even 
put  an  end  to  the  nascent  colony. 


86  HYMEXOPTERA 


CHAT- 


destroyed  and  reformed,  as  the  combs  they  contain  increase  in 
size.  Marchal's  observations  l  relate  chiefly  to  the  production  of 
the  sexes  and  worker-forms,  in  the  subterranean  species,  J~cspa 
germanica  and  I",  rulgaris.  The  layers  of  comb  include  cells  of 
two  sizes.  The  upper  layers,  which  are  the  first  formed,  consist 
of  small  cells  only :  the  lower  combs  are  constructed  (at  Paris) 
early  in  August,  and  consist  of  larger  cells  from  which  males 
and  large  females  are  reared.  The  males  are,  however,  reared 
also  in  large  numbers  in  the  small  cells.  If  the  queen  be  re- 
moved, the  workers  become  fertile,  and  produce  paithenogenetically 
many  eggs,  but  all  of  the  male  sex.  He  entertains  no  doubt 
that  even  when  the  queen  is  in  full  vigour  the  workers  produce 
males  if  there  is  an  abundant  food  supply. 

The  social  wasps  at  present  known  number  500  or  600  species. 
Pollutes  is  a  very  extensive  genus,  and  it  has  also  a  very  wide 
geographical  distribution  :  some  of  the  species — and  those  found  in 
widely-distant  parts  of  the  world — are  remarkable  on  account  of 
their  excessive  variation  in  colour,  and  it  is  worthy  of  note  that  the 
extreme  forms  have  been  more  than  once  taken  from  the  same  nest. 

Xext  to  Polistes,  l^espa  is  the  most  numerous  in  species, 
about  150  being  known,  and  it  is  to  this  genus  that  all  our 
British  social  wasps  belong.  Xo  Insects  are  .better  known 
in  our  islands  than  these  wasps,  owing  to  the  great  numbers 
of  individuals  that  occur  in  certain  seasons,  as  well  as  to 
their  frequently  entering  our  habitations  and  partaking  of  our 
food,  and  to  the  terror  that  is  occasioned  by  their  supposed 
ferocity  and  desire  to  sting.  This  last  feature  is  a  complete 
mistake ;  wasps  never  sting  unless  they  are  roused  to  do  so  by 
attacks,  or  by  considerable  interference  with  their  work.  The 
only  real  danger  arises  from  the  fact  that  a  wasp  may  be  occa- 
sionally taken  into  the  mouth  with  fruit,  or  may  be  handled 
unawares.  "\Vhen  they  are  flying  about  they  are  perfectly 
harmless  unless  attacked  or  irritated,  and  even  if  they  settle 
on  the  person  no  danger  of  their  stinging  exists  unless  move- 
ment is  made.  Sichel  correctly  states  that  a  person  may 
station  himself  close  to  a  wasp's  nest  and  'remain  there  without 
any  risk  at  all,  provided  that  he  makes  no  movement ;  indeed,  it 
is  more  than  probable  that  if  no  movement,  or  if  only  gentle 

1  CE.  Ac.   Paris,  cxvii.   1S93,  p.  584  ;  op.  cit.  cxxi.  1895,  p.  731  ;  Arch.  Zool. 
exper.  (3)  iv.  1896,  pp.  1-100. 


II 


VESPIDAE SOCIAL  WASPS 


movement,  be  made,  the  wasps  are  unaware  of  the  presence  of  an 
intruder.  It  is,  however,  well  ascertained  that  if  they  are 
molested  at  their  work,  more  especially  when  they  are  actually 
engaged  in  the  duties  of  the  nest,  they  are  then  extremely  vin- 
dictive, and  follow  for  a  considerable  distance  those  who  have 
irritated  them.  The  East  Indian  V.  velutina  is  specially  fierce 
when  aroused,  and  is  said  by  Home  to  have  followed  a  party 


/* 


r-<  vj-:^-  ' 

- 


FK;.  34. — Ischnoyaster  mdlyi.  Java.  A,  Female  imago  (the  line  at  the  side  shows  its 
length)  ;  B,  nest,  C,  maxilla  ;  D,  labiuni  ;  E.  mandible  (tip  downwards).  The  nest 
is  probably  upside  down,  although  shown  here  as  by  de  Saussure. 

through  dense  jungle  for  miles,  and  on  some  occasions  to  have 
stung  animals,  and  even  human  beings,  to  death. 

This  vindictiveness  is,  however,  only  an  exceptional  mood  due 
to  some  interference  with  the  colony.  Even  the  hornet,  not- 
withstanding its  threatening  appearance,  is  harmless  unL  •  — 
unduly  provoked  ;  its  nests  and  their  inhabitants  can  be  kept  in 
domesticity,  exhibited  to  strangers,  even  moved  from  place  to 
place,  yet  the  hornets  will  not  take  offence  if  due  gentleness  be 
observe  1.  It  is  said  that  wasps  will  rear  the  progeny  of  a  neigh- 
bour in  circumstances  where  this  assistance  is  necessurv.  Hess 

w 

has  related  a  case  in  which  a  queen-hornet  had  commenced  a  nest, 
and  was   killed  by  an  accident,  leaving  young  brood  in  the  comb 


88 


HYMENOPTERA 


CHAP. 


unprovided  for  :  as  a  result  many  of  the  helpless  grubs  died,  and 
others  were  in  a  state  of  starvation,  when  a  strange  queen-hornet 
appeared,  associated  itself  with  the  comb,  and,  adopting  the  orphan 
brood,  nourished  them  and  brought  them  to  their  full  size. 

We  have  already  alluded  to  the  fact  that,  so  far  as  external 
structure  is  concerned,  there  is  no  great  difference  between  the 
social  and  the  solitary  wasps.  Both,  too,  run  through  analogous 
series  of  forms  and  colours,  and  the  genus  Isclmoy aster  (Fig.  34) 
seems  to  connect  the  two  groups  by  both  its  structure  and  mode 
of  life.  The  social  habits  are  in  many  species  only  inferred,  and 
with  greater  knowledge  will  probably  prove  fallacious  as  a  guide 
to  classification  ;  indeed  we  have  already  said  that  in  the  genus 
Vespa — perhaps  the  most  perfectly  social  of  all  the  wasps — there 

is  one  species  that  has  no  worker, 
and  that  lives,  it  is  supposed,  as 
a  parasite,  in  the  nests  of  its 
congeners.  For  this  species,  V. 
austriaca,  it  has  been  proposed  to 
create  a  separate  genus,  Pseudo- 
vespa,  on  account  of  this  peculiarity 
of  habit,  although  no  structural 
character  has  been  detected  that 
could  distinguish  it.  De  Saussure 
has  stated  his  conviction  that 
workers  do  not  exist  in  some  of 
the  exotic  genera,  so  that  it  appears 
highly  probable  that  with  the  pro- 
gress of  knowledge  the  present  divi- 
sion between  social  and  solitary 
wasps  will  prove  untenable. 

Remains  of  Insects  referred  to 
the  genera  Polistes  and  Vcspa 
have  been  found  in  tertiary  strata 


FIG.  35. — Masaris  vespiformis.   A,  male 
B,  female.     Egypt.      (Ar'ter  Schaum.) 


in  various  parts  of  Europe  and  in  North  America. 

Fam.  3.  Masaridae. 

Anterior  winy  with  two  complete  sub-marginal  cells.  Antennae 
tixindly  incrassate  or  clubbed  at  the  extremity.  Claws  dis- 
tinctly or  oljsoletely  dentate. 

This  is  a  group  of  fifty  or  sixty  species  with  but  few  genera, 


MASARIDAE 


89 


and  most  of  its  components  appear  to.  be  Insects  of  the  greatest 
rarity.  In  their  appearance  the  Insects  of  this  Family  differ  con- 
siderably from  the  other  Diploptera,  and  as  the  wings  are  only 
imperfectly,  or  not  at  all,  plicate,  it  must  be  admitted  that  the 
systematic  affinities  of  the  group  require  reconsideration.  The 
pronotal  structure  is,  however,  completely  that  of  Diploptera. 
The  typical  form  of  the  Family,  Masaris  vespiformis,  though 
described  a  hundred  years  since,  is  a  species  of  such  ex- 
treme rarity,  and  its  sexes  are  so  different,  that  entomologists 
have  only  recently  been  able  to  agree  about  it.  It  has  been 
found  in  Egypt  and  Algeria.  The  genera  Ceramius,  Jugurthia, 
<t>"<trtenia  and  Coelonites  are  also  members  of  the  Mediterranean 
fauna,  while  Paragia  is  Australian,  and  Trimeria  South  American. 
Several  species  of  the  genus  Masaris  inhabit  Xorth  America,  and 
Cresson  has  recently  described  another 
Masarid  genus  from  the  same  country, 
under  the  name  of  Et'j>i/i'i/i/i</. 

The  little  that  is  known  of  their 
natural  history  is  almost  limited  to  an 
account  given  by  Giraud  of  the  habits  of 
Ceramics  lusitanicus,  of  which  species  he 
found  a  colony  near  Briangon.  The  Insect 
makes  nests  in  the  earth  ;  they  are  entered 
by  means  of  a  chimney  -  like  passage 
analogous  to  what  is  formed  by  certain 
Odynerus ;  the  gallery  when  completed  is 
about  six  centimetres  long,  and  at  its 
extremity  is  an  earthen  cell  in  which  the 
larva  lives ;  this  is  fed  by  the  mother, 
who  brings  to  it  from  time  to  time  a 
supply  of  a  paste,  described  as  being 
somewhat  like  dried  honey.  The  growth 
of  the  larva  is  believed  to  be  rapid. 

Some  fragmentary  observations  made 
by  Lichtenstein  on  Coelonites  abbreviatus  have  also  been  recorded. 
This  species,  near  Montpellier,  constructs  earthen  cells ;  they  are 
not,  however,  subterranean,  but  are  placed  side  by  side  on  the  dry 
stems  of  plants  (Fig.  36);  these  cells  are  stored  with  a  material 
similar  to  that  supplied  by  Ceramius  lusitanicus  to  its  young. 


FIG.  36.  —  Cells  constructed 
by  Coelonites  abbreviatus. 
(After  Andre.) 


CHAPTER   III 

HYMENOPTERA  ACULEATA  COXTIXUE1) DIVISION  III.  FOSSORES  OR 

FOSSORIAL  SOLITARY  WASPS — FAMILY  SCOLIIDAE  OR  SUBTER- 
RANEAN FOSSORS FAMILY  POMPILIDAE  OR  RUNNERS FAMILY 

SPHEGIDAE  OR  PERFECT-STINGERS 

Division  III.    Fossores. 

Aculeate  Hymenoptera,  in  which  the  abdomen,  thouyh  very  diverse 
inform,  does  not  bear  prominences  on  the  upper  aspect  of  the 
basal  segments  ;  front  iving  without  longitudinal  fold  along 
the  middle  ;  hairs  of  body  nut  plumose.  Only  two  forum 
(male  and  female)  of  each  specie*. 

FOSSORIAL  Hymenoptera  are  distinguished  from  other  Aculeates 
at  present  only  by  negative  characters,  i.e.  they  are  Aculeates, 
but  are  not  ants,  bees  or  wasps.  According  to  their  habits  they 
fall  into  four,  by  no  means  sharply  distinguished,  groups — (1) 
those  that  form  no  special  receptacles  for  their  young,  but  are 
either  of  parasitic  or  sub-parasitic  habits,  or  take  advantage  of 
the  abodes  of  other  Insects,  holes,  etc. ;  (2)  constructors  of  cells 
of  clay  formed  into  pottery  by  the  saliva  of  the  Insect,  and  by 
drying  ;  (3)  excavators  of  burrows  in  the  ground  ;  (4)  makers  of 
tunnels  in  wood  or  stems  of  plants.  Several  species  make  use 
of  both  of  the  last  two  methods.  The  habits  are  carnivorous ; 
the  structures  formed  are  not  for  the  benefit  of  the  makers,  but 
are  constructed  and  stored  with  food  for  the  next  generation. 
Their  remarkable  habits  attracted  some  attention  even  2000 
years  or  more  ago,  and  were  to  some  extent  observed  by  Aristotle. 
The  great  variety  in  the  habits  of  the  species,  the  extreme 
industry,  skill,  and  self-denial  they  display  in  carrying  out  their 
voluntary  labours,  render  them  one  of  the  most  instructive  groups 
of  the  animal  kingdom.  There  are  no  social  or  gregarious 


CHAP.    Ill 


FOSSORIAL  SOLITARY  WASPS 


forms,  they  are  true  individualists,  and  their  lives  and  instincts 
offer  many  subjects  for  reflection.  Unlike  the  social  Insects  they 
can  learn  nothing  whatever  from  either  example  or  precept. 
The  skill  of  each  individual  is  prompted  by  no  imitation.  The 
life  is  short,  the  later  stages  of  the  individual  life  are  totally 
different  from  the  earlier :  the  individuals  of  one  generation 
only  in  rare  cases  see  even  the  commencement  of  the  life  of  the 
next ;  the  progeny,  for  the  benefit  of  which  they  labour  with 


FIG.  37. — Scelifthron  nigripes  9  (Sub-Fam.  Sphegides).     Amazons,      x  \. 

unsurpassable  skill  and  industry,  being  unknown  to  them.  Were 
such  a  solicitude  displayed  by  ourselves  we  should  connect  it 
with  a  high  sense  of  duty,  and  poets  and  moralists  would  vie  in 
its  laudation.  But  having  dubbed  ourselves  the  higher  animals, 
we  ascribe  the  eagerness  of  the  solitary  wasp  to  impulse  or 
instinct,  and  we  exterminate  their  numerous  species  from  the  face 
of  the  earth  for  ever,  without  even  seeking  to  make  a  prior  ac- 
quaintance with  them.  Meanwhile  our  economists  and  moralists 
devote  their  volumes  to  admiration  of  the  progress  of  the  civilisa- 
tion that  effects  this  destruction  and  tolerates  this  negligence. 


92  HYMENOPTERA  CHAP. 

It  should  be  noted  that  in  the  solitary  as  in  the  social  Insects 
the  males  take  no  part  whatever  in  these  industrial  occupations,- 
and  apparently  are  even  unaware  of  them.  It  is  remarkable 
that,  notwithstanding  this,  the  sexual  differences  are  in  the 
majority  less  than  is  usual  in  Insects.  It  is  true  that  the  various 
forms  of  Scoliidae  exhibit  sexual  distinctions  which,  in  the  case 
of  Thynnides  and  Mutillid.es  are  carried  to  an  extreme  degree, 
but  these  are  precisely  the  forms  in  which  skill  and  ingenuity  are 
comparatively  absent,  the  habits  being  rather  of  the  parasitic 
than  of  the  industrial  kind,  while  the  structure  is  what  is 
usually  called  degraded  (i.e.  wingless).  The  great  difference 
between  the  habits  of  the  sexes,  coupled  with  the  fact  that  there 
is  little  or  no  difference  in  their  appearance,  has  given  rise  to  a 
curious  Chinese  tradition  with  regard  to  these  Insects,  dating 
back  to  Confucius  at  least.1  The  habit  of  stinging  and  storing 
caterpillars  in  a  cell,  from  which  a  fly  similar  to  itself  afterwards 
proceeds  having  been  noticed,  it  was  supposed  to  be  the  male  that 
performed  these  operations  ;  and  that  when  burying  the  cater- 
pillars he  addressed  to  them  a  spell,  the  burden  of  which  is 
•'  mimic  me."  In  obedience  the  caterpillars  produce  the  wasp, 
which  is  called  to  this  day  "  Jiga,"  that  is  in  English  "  mimic 
me."  The  idea  was  probably  to  the  effect  that  the  male,  not 
being  able  to  produce  eggs,  used  charmed  caterpillars  to  continue 
the  species. 

Summary  of  the  Prey  of  Fossores. 

Group  of  Fossores.  F<  M  id  or  Occurrence. 

Fam.  Scoliidae. 

Sub-Fain.   Mutillides      .      .  As  parasites  on  Hymenoptera  Aculeata. 
.,          Thynnides     .      .  (?)  Parasites  on  Lepidopterous  pupae. 
.,         Scoliides  .     .     .  Larvae  of  Coleoptera  [(?)  spiders  in  the  case  of 

Elis  4-»ofr/fr(]. 

.,          Rhopalosomides.   Unknown. 
„         Sapygides       .     .  The  provisions  stored  by  bees.      Caterpillars 

(teste  Smith). 

p         p        .,.  ,  (Spiders.     Rarely  Orthoptera  (Gryllidae  and 

{       Blattidae,  teste  Bingham)  or  Coleoptera. 
/  Orthoptera    (especially    Locustidae),    larvae 

Fain.  Sphegidae.  )       of  Lepidoptera,  Spiders  [(?)  same  species 

Sub-Fain.  Sphegides      .      .     \       (Sceliphron    madraspatanum    and     Sphex 

),  both  spiders  and  caterpillars]. 


Kumagusu  Minakata,  in  Nature,  1.  1894,  p.  30. 


Ill 


FOSSORIAL  WASPS 


93 


Group  of  FossoreG. 

Fam.   Sphegidae. 

Sub-Fam.  Ampulicides . 
Larrides  . 


„          Trypoxylonides , 
Astatides  . 


Food  or  Occurrence. 

Orthoptera  (Blattidae  only). 

Orthoptera    of    various    divisions.       Aculeate 

Hymenoptera,     in    the     case     of    Palarus. 

[Spiders  stolen  from  nests  of  Pelopaeus  by 

Larrada.] 

Spiders,  caterpillars,  Aphidae. 
Astata  loops  uses  Pentatomid  bugs,  cockroaches, 

and  even  Aculeate  Hymeiioptera  (Oxylelus, 

teste  Smith). 
Diptera  and  Cicada. 
Diptera,   Homoptera   (Gorytes    mystaceus   takes 

Aplirophora  out  of  its  "  cuckoo-spit  "). 
Aculeate    Hymenoptera    (Philantlius).       Hard 

beetles,    viz.     Curculionidae,     Buprestidae, 

Chrysomelidae  (Cerceris). 
Small    Homoptera,    even    Aphidae.     Diptera 

(Tipulidae)  in  Hawaii. 
Diptera,  Aphidae  [?  the  same  species  of  wasps 

both   of   these].      Other   small    Homoptera. 

Ants  (in  the  case  of  Fertonius).      Parasitic 

optera  (in  the  case  of  Lindenius). 

Great  diversity  of  opinion  exists  as  to  the  classification  of  the 
Fossores.  This  arises  chiefly  from  the  incomplete  state  of  the 
collections  studied,  and  from  the  fact  that  the  larger  part  of  the 
works  published  are  limited  to  local  faunae.  Opinions  as  to  the 
families  vary ;  some  admitting  only  three  or  four,  others  upwards 
of  twenty.  After  consideration  of  the  various  views,  the  writer 
thinks  it  best  to  admit  at  present  only  three  families,  which 
speaking  broadly,  correspond  with  habits,  viz.  (1)  Scoliidae, 
subterranean  stingers;  (2)  Pompilidae,  runners;  (3)  Sphegidae, 
stingers  above  ground. 


Bembecides 
Nyssonides    . 

Philanthides 


Mimesides 


Crabronides 


1.  Scoliidae.     Pronotum   and   tegulae    in   contact.      Abdomen   with   the 

plane  of  the  ventral  surface  interrupted  by  a  chink   between  the 
first  and  second  segments.      Numerous  wingless  forms. 

2.  Pompilidae.      Pronotum  and   tegulae  in  contact.      Abdomen  with   the 

plane   of  the  ventral  surface   not  interrupted    by  a   chink.      Legs 
very  long.      No  wingless  forms. 

3.  Sphegidae.      Pronotum    and    tegulae    not    in    contact.      No    wingless 

forms. 


We  shall  treat  as  sub-families  those  divisions  of  Scoliidae  and 
Sphegidae  considered  by  many  as  families. 


94  HYMENOPTERA  CHAP. 

Fam.  1.  Scoiiidae. 

The  members  of  this  family,  so  far  as  is  known,  display  less 
perfect  instincts  than  the  Sphegidae  and  Pompilidae,  and  do  not 
construct  cells  or  form  burrows.  Information  as  to  the  habits  is 
almost  confined  to  European  forms.  AVe  adopt  five  sub-families. 

Sub-Fam.  1.  Mutillides.--77/r  stiles  of  the  pronotum,  reach  the 
ti'ijiilae  :  the  female  is  destitute  of  wings  and  ocelli, 
frequently  h.aviny  I  In1  parts  of  f/ir  thorax  so  closely  soldered 
that  the  divisions  between  them  are  obliterated :  the  males  are 
winged,  furnished  with  ocelli,  and  having  the  thoracic  divisions 
distinct ;  intermediate  tibiae  with  tiuo  apical  spurs.  Front 
i  ring  with,  two  or  three  suh-i>mryi  iml  fells.  The  larvae  live 
parasitically  at  the  expense,  of  other  Hymenoptera  Aculeata. 

The  Mutillides  have  some  resemblance  to  ants,  though,  as 
they  are  usually  covered  with  hair,  and  there  is  never  any  node 
at  the  base  of  the  abdomen,  they  are  readily  distinguished  from 
the  Formicidae.  The  great  difference  between  the  sexes  is  their 
most  striking  character.  Their  system  of  coloration  is  often 
very  remarkable,  the  velvet-like  pubescence  clothing  their  bodies 
being  variegated  with  patches  of  sharply  contrasted  vivid  colour  : 
in  other  cases  the  contrast  of  colour  is  due  to  bare,  ivory-like 
spaces.  They  have  the  faculty  of  stridulating,  the  position  and 
nature  of  the  organ  for  the  purpose  being  the  same  ;is  in  ants. 

Very  little  exact  information  exists  as  to  the  habits  and  life- 
histories  of  the  species.  Christ  and  Drewsen,  forty  or  fifty  years 
ago,  recorded  that  M.  euro'paea  lives  in  the  nests  of  bees  of  the 
genus  Jiombus,  and  Hoffer  has  since  made  some  observations  on  the 
natural  history  of  the  same  species  in  South  East  Europe,  where 
this  Mitt  ill  a  is  found  in  the  nests  of  ten  or  eleven  species  of 
Bombus,  being  most  abundant  in  those  of  B.  ayrorum,  and  B. 
variabilis ;  occasionally  more  individuals  of  Mnfilln  than  of  bees 
may  be  found  in  a  nest.  He  supposes  that  the  egg  of  the 
Ma tHlu,  is  placed  in  the  young  larva  of  the  Bombux,  and  hatches 
in  about  three  days;  the  larva  feeds  inside  the  bee-larva,  and 
when  growth  is  completed  a  cocoon  is  spun  in  the  interior  of 
the  pupa -case  of  the  bee.  When  the  perfect  Insects  emerge, 
the  males  leave  the  nest  very  speedily,  but  the  females  remain 
for  some  time  feeding  on  the  bees'  honey.  Females  are  usually 
produced  in  greater  numbers  than  males.  This  account  leaves 


Ill 


SCOLIIDAE—  MUTILLIDES 


95 


much  to  be  desired.  From  the  observations  of  Radoszkowsky 
it  is  clear  that  other  species  of  Mutillides  are  by  no  means 
confined  to  the  nests  of  Bovibus  but  live  at  the  expense  of 
Aculeate  Hymenoptera  of  various  groups.  This  naturalist  asserts 
that  the  basal  abdominal  segment  of  the  parasite  resembles  in 
form  that  of  the  species  on  which  it  preys. 

The  apterous  condition  of  the  females  of  Mutillides  and 
Thynnides  is  very  anomalous  in  the  Fossors ;  this  sex  being  in 
the  other  families  distinguished  for  activity  and  intelligence. 
The  difference  between  the  sexes  is  also  highly  remarkable.  The 
males  differ  from  the  females  by  the  possession  of  wings  and  by  the 
structural  characters  we  have  mentioned,  and  also  in  a  most  striking 


8 


FIG.  38. — Mutilla  stridula.     Europe.     A,  Male  ;  B,  female. 

manner  in  both  colour  and  form  ;  Burmeister,  indeed,  says  that  in 
South  America — the  metropolis  of  Mutillides — there  is  not  a  single 
species  in  which  the  males  and  females  are  alike  in  appearance ;  this 
difference  becomes  in  some  cases  so  extreme  that  the  two  sexes  of 
one  species  have  been  described  as  Insects  of  different  families. 

Upwards  of  one  thousand  species  are  assigned  to  the  genus 
Mutilla,  which  is  distributed  over  the  larger  part  of  the  world ; 
there  is  so  much  difference  in  these  species  as  to  the  nervuration 
of  the  wings  in  the  males,  that  several  genera  would  be  formed 
for  them  were  it  not  that  no  corresponding  distinctions  can  be 
detected  in  the  females.  Three  or  four  species  of  Mutilla  are 
described  as  being  apterous  in  the  male  as  well  as  in  the 
ft -male  sex  ;  they  are  very  rare,  and  little  is  known  about  them. 
Only  three  species  of  Mutillides  occur  in  Britain,  and  they  are 
but  rarely  seen,  except  by  those  who  are  acquainted  with  their 


Q6 


HYMENOPTERA 


CHAP. 


habits.  The  African  and  East  Indian  genus,  Apterogyna,  includes 
some  extremely  peculiar  Hymenoptera  ;  the  males  have  the  wing 
nervuratioii  very  much  reduced,  and  the  females  are  very  ant-like. 
owing  to  the  deep  constriction  behind  the  first  abdominal  ring. 

Sub-Fam.  2.    Thynnides.  —  Males  and  females  very  different  in 

form;    the   male  winged,  the  front  winy  with    three,   or   on/// 

two,  sub-marginal   cells  ;   the  female  wingless   and  with   ///> 

thorax  divided  into  three  sub-equal 


FIG.  39. — Methoca  ichneumonides.     A,  Male  ;  B,  female. 

Britain. 


The  Thynnides  are  by  some  entomologists  not  separated  from 

theMutillides;  but 
the  distinction  in 
the  structure  of 
the  thorax  of  the 
females  is  very 
striking.  In  the 
Thynnides  the 
nervuratioii  of  the 
wing  appears 
always  to  extend 
to  the  outer 
margin,  and  in  the 
Muti  Hides  not  to 
do  so.  This  family 
is  represented  in 
Britain  by  a  single  very  rare  Insect,  Methoca  ichneumonides  :  to 
the  unskilled  observer  the  female  would  appear  to  be  without 
doubt  an  ant.  This  Insect  is  by  some  considered  as  the  type 
of  a  family  distinct  from  the  Thynnides  proper.  Thynnides  are 
numerous  in  Australia.  Very  little  is  really  known  as  to  their 
habits,  though  it  has  been  stated  that  they  are  parasitic  on 
Lepidoptera,  Bakewell  having  obtained  specimens  from  sub- 
terranean cocoons  of  that  Order.  Those  who  are  interested  in 
differences  between  the  sexes  of  one  species  should  examine  the 
extraordinary  examples  of  that  phenomenon  presented  by  the 
Thynnides  ;  the  dissimilarity  throughout  the  group  —  which  is 
now  of  considerable  extent  —  being  so  extreme  that  no  ento- 
mologist would  from  simple  inspection  believe  the  two  sexes 
to  have  any  connection  ;  but  the  fact  that  they  are  so  con- 
nected has  been  demonstrated  beyond  doubt.  In  very  few 


Ill 


SCOLIIDAE THYNNIDES SCOLIIDES 


97 


cases,  however,  have  the  sexes  been  matched,  so  that  at  present 
males  are  no  doubt  standing  in  the  lists  of  Hymenoptera  as  one 
species  and  their  females  as  other  species. 

Sub-Fam.  3.  Scoliides. — Pronotum  reaching  back  to  the  tegulae ; 
legs  stout;  intermediate  tibiae  until  one  apical  spur;  both 
sexes  winged ;  the  nervures  not  extending  to  the  posterior 
(i.e.  distal}  margin. 

This  group  includes  some  of  the  largest  and  most  powerful  of 
the  Aculeate  Hymenoptera.  Its  members  are  usually  hairy 
Insects  with  thick  legs, 
the  colour  being  black, 
more  or  less  variegated 
with  bands  or  spots  of 
red  or  yellow  ;  the  hind 
body  is  elongate,  has 
only  a  very  short  pedi- 
cel, and  in  the  male 
is  usually  termin- 
ated by  three  project- 
ing spines.  The  pro- 
notum  is  of  variable 
dimensions,  but  its  front 
angles  are  always  co- 
adapted  with  the  points  of  insertion  of  the  front  wings.  The 
nervuratioii  of  the  front  wings  is  confined  to  the  basal  part,  the 
extensive  apical  or  outer  area  possessing  no  nervures.  There  is 
frequently  a  great  difference  in  the  size  of  the  two  sexes  of  the  same 
species,  the  female  being  very  much  larger  than  the  other  sex.  The 
larvae,  so  far  as  is  known,  devour  those  of  Lamellicorn  Coleoptera. 

Fabre  has  investigated  the  habits  of  some  of  the  species  of 
Scoliides  found  in  France,  and  has  informed  us  that  their  means 
of  subsistence  consists  of  larvae  of  the  larger  Lamellicorn  beetles, 
Cetonia,  Oryctes,  Anoxia,  and  Euclilora  ;  these  beetles  belong  to 
very  different  divisions  of  the  Lamellicornia,  but  they  have  in 
common  the  fact  that  their  larvae  are  of  subterranean  habits, 
living  in  the  earth  or  in  accumulations  of  debris  in  which  there 
is  a  large  proportion  of  vegetable  matter  or  roots.  The  female 
Scolia  penetrates  into  the  ground  in  order  to  find  the  Lamellicorn 
larvae  necessary  as  food  for  its  progeny.  Scolia  bifasciata 

VOL.  VI  H 


FIG.  40. — Scolia  haemorohoidalis  9-     Europe. 


98  HYMENOPTERA  CHAP. 

attacks  the  larvae  of  several  species  of  Cetonia,  and  S.  (Colpa) 
interrupta  chooses  the  larvae  of  the  chafers  Anoxia  villosa  and 
A.  matutinalis.  The  mother  Scolia  enters  the  ground  in  August 
or  September,  and  having  found  a  suitable  larva  stings  it  and 
deposits  an  egg  on  the  ventral  surface  of  the  prey  ;  the  paralysed 
larva  is  left  where  it  was  found,  no  attempt  being  made  to  place 
it  in  a  special  receptacle.  The  egg  is  placed  on  the  ventral 
surface,  well  behind  the  feet,  under  a  mass  of  matter  in  the 
alimentary  canal.  Shortly  after  being  hatched  the  young- 
destroyer  penetrates  with  its  head  the  skin  of  the  victim,  and  in 
this  position  commences  to  feed ;  it  is  necessary  that  it  should 
obtain  its  food  without  killing  the  Cetonia  larva,  for  it  cannot 
prosper  on  decaying  food,  so  that  if  the  Cetonia  larva  die  the 
Scolia  larva  likewise  perishes  ;  the  latter,  accordingly,  does 
not  withdraw  its  head  from  the  interior  of  the  victim,  but 
remains  always  in  the  same  position,  as  it  grows  larger  extending 
its  head  forwards  into  the  front  part  of  the  interior  of  its  victim  ; 
the  internal  organs  of  the  latter  are  consumed  in  a  systematic 
order  so  as  to  delay  bringing  about  its  death  till  the  last  moment, 
and  thus  all  the  interior  of  the  Cetonia  larva  is  appropriated  till 
nothing  remains  but  an  empty  skin.  By  a  series  of  experiments, 
Fabre  showed  how  essential  it  is  that  this  apparently  revolting 
operation  should  be  carried  on  with  all  details  strictly  en  regie. 
If  the  head  of  the  Scolia  larva  be  taken  out  from  the  victim  and 
applied  to  another  part  of  the  body  of  the  Cetonia,  the  result  is 
that  it  cannot  eat ;  even  if  it  be  replaced  in  the  original  situa- 
tion, after  being  taken  away,  it  frequently  happens  that  the 
Cetonia  larva  dies,  its  death  involving  also  that  of  the  destroyer. 
It  is  necessary,  too,  that  the  victim  should  be  paralysed,  for  if  an 
intact  Cetonia  larva  be  taken  and  bound  down  in  such  a' position 
that  it  cannot  move,  and  if  a  small  orifice  in  its  skin  be  made  in 
the  proper  spot  and  a  young  Srolia  larva  be  placed  on  it,  the 
little  parasite  will  avail  itself  of  the  opportunity  and  commence 
to  feed  on  the  larva  provided  for  it,  but  the  latter  will  speedily 
die,  and  the  Scolia  necessarily  perishes  with  it.  Thus  both  the 
paralysis  of  the  victim  and  the  special  mode  of  eating  are  essential 
to  the  life  of  the  Scolia.  The  operation  of  stinging  the  larva,  so 
as  to  produce  the  necessary  paralysis,  or  rather  insensibility,  is  a 
difficult  one,  and  requires  great  skill  and  patience.  The  Cetonia 
larva  is  of  large  size,  and  must  be  pierced  in  one  particular  spot ; 


in  SCOLIIDAE SCOLIIDES SAPYGIDES  99 

in  order  to  reach  this  the  Scolia  mounts  on  its  victim,  and  is 
frequently  dislodged  by  its  struggles ;  sooner  or  later,  however, 
the  proper  position  is  obtained  by  the  wasp,  and  the  larva  is 
then  stung  in  the  exact  spot  necessary  to  allow  the  sting  (and  the 
poison  introduced  by  it)  to  reach  the  most  important  of  the 
nervous  ganglia  that  control  the  movements  of  the  body,  this  spot 
being,  in  the  case  of  the  Cetonia,  the  line  of  demarcation  between 
the  pro-  and  meso-thorax,  on  the  middle  line  of  the  ventral 
surface  of  the  body.  The  Scolia  gives  but  one  sting  to  the 
victim,  and  this  it  will  not  administer  until  it  can  do  so  exactly 
in  the  proper  place.  This  practice  of  devouring  the  victim 
slowly,  without  killing  it  till  all  is  eaten,  is  very  widely  spread  in 
the  Hymenoptera,  and  it  is  satisfactory  to  find  that  we  may  infer 
from  Fabre's  observations  that  it  is  not  so  horrible  as  it 
would  at  first  appear ;  for  it  is  probable  that  the  stinging 
prevents  decomposition  of  the  victim,  not  by  reason,  as  some  have 
supposed,  of  the  poison  injected  by  the  wasp  having  an  antiseptic 
effect,  but  rather  by  means  of  destroying  sensibility,  so  that  the 
creature  does  not  die  from  the  pain,  as  it  is  believed  it  did  in 
certain  cases  where  Fabre  induced  the  young  Scolia  larva  to  feed 
on  a  victim  that  had  not  been  stung.  We  may  here  remark 
that  very  little  exact  information  exists  as  to  the  operation  of 
stinging.  Fabre  attaches  great  importance  to  the  sting-  being 
inflicted  on  a  nerve -ganglion.  Whether  a  sting  that  did  not 
reach  this  part  might  not  have  a  sufficient  effect  appears,  how- 
ever, doubtful.1 

A  remarkable  form  of  Scoliides,  with  wings  of  smaller  size 
than  usual  and  deeply  divided,  has  been  described  by  Saunders 
under  the  name  Pseudomeria  graeca.  Still  more  remarkable  is 
Komarovia  victoriosa  found  in  Central  Asia  ;  in  this  Insect  the 
male  retains  the  appearance  of  a  slender,  pallid  Scolia,  but  the 
female  differs  totally  in  form,  and  has  the  peculiar  wings  so  re- 
duced in  size  as  to  be  useless  for  flight. 

Sub-Fam.  4.  Sapygldes. — Closely  allied  to  the  Scoliides,  but  j>os- 
sessing  slender  legs  and  antennae ;  also  the  first  abdominal 
segment  is  less  disconnected  from  the  second,  so  that  the  outline 

1  As  this  work  is  passing  through  the  press  we  receive  a  book  by  Mr.  and  Mrs. 
Peckhani  on  The  Instincts  and  Habits  of  the  Solitary  Wasps,  Madison,  1898. 
They  are  of  opinion  that,  in  the  case  of  some  species,  it  does  not  matter  much 
whether  the  victim  is  or  is  not  killed  by  the  stinging. 


100 


HYMENOPTERA 


CHAT. 


FIG.  41. — $cij>i/yn  -l-j/i'/tctata  ?, 
Britain. 


is  less  interrupted ;  the  eyes  are  deeply  emarginate ;  the  hind 
body  is  not  spinose  at  the  apex. 

The  economy  of  Sapygn,  the  only  genus,  has  been  the  subject 

of  difference  of  opinion.  The  views 
of  Latreille  and  others  that  these 
species  are  parasitic  upon  bees  is 
confirmed  by  the  observations  of 
Fabre,  from  which  it  appears  that 
S.  5 -punctata  lives  in  the  burrows 
of  species  of  the  bee-genus  Osmia, 
consuming  the  store  of  provisions, 
consisting  of  honey-paste,  that  the 
bee  has  laid  up  for  its  young.  Ac- 
cording to  the  same  distinguished 
observer,  the  Sapyga  larva  exhibits 

h\ -pel-metamorphosis  (i.e.  two  consecutive  forms),  and  in  its  young 

state  destroys  the  egg  of  the  bee  ;  but  his  observations  on  this  point 

are  incomplete  and  need 

repetition.   AVe  have  two 

species     of    Sapyga    in 

Britain  ;    they   differ   in 

,  *•• 

colour,  and  the  sexes  of 
S.  5 -punctata  also  differ 
in  this  respect ;  the 
a  bdomen ,  spot  t  e  d  with 
white  in  both  sexes,  is 
in  the  female  variegate 
with  red.  Smith  found 
our  British  Sapyga  o- 
punctata  carrying  cater- 
pillars. 


"CR- 


Sub-Fam.   5.   Rhopalo- 
somides.  --Antennae 

elongate,  spinigerous  ;       FIG.  42. — Rhopalosoma poeyi.     A,  female  imago  ; 

ocelli  very  prominent ;         B< IVoilt  of "    Cuba"    (After  Westwood-) 
tarsi  of  peculiar  structure,  their  claws  bifid. 

This  sub-family  has  recently  been  proposed  by  Ashmead  J  for 

1   P.  cut.  Soc.   Washington,  iii.  1896,  p.  303. 


in  FOSSORES  101 

an  extremely  rare  American  Insect  that  had  previously  been  placed 
by  Cresson  among  parasitic  Hymenoptera.  Westwood  classed 
RJiopalosoma  among  Diploptera,  saying  of  it  "  animal  quoad 
affmitates  excrucians."  We  reproduce  Westwood's  figure,  but  not 
being  acquainted  with  the  Insect  we  can  express  no  opinion  as  to 
whether  it  is  allied  to  the  Scoliidae  or  to  the  Sphegidae.  The 
habits  are,  we  believe,  quite  unknown. 

Fam.  2.  Pompilidae. 

Pronotum  at  the  sides  reaching  the  tegulae ;  hind  body  never 
definitely  pedicellate,  though  the  first  segment  is  sometimes 
elongate  and  conical;  hind  legs  long  ;  eyes  elliptic  inform, 
not  emarginate. 

The  Pompilidae  are  perhaps  the  most  extensive  and  important 
of  the  groups  of  Fossores,  and  are  distributed  over  all  the  lands  of 
the  globe,  with  the  exception  of  some  islands  and  of  the  inclement 
arctic  regions.  The  sting  of  the  Pompilidae,  unlike  that  of  most 
of  the  Fossores,  inflicts  a  burning  and  painful  wound;  the  creatures 
sometimes  attain  a  length  of  two  or  three  inches,  and  a  sting  from 
one  of  these  giants  may  have  serious  results.  Although  there  is 
considerable  variety  in  the  external  form  of  the  members  of  the 
group,  the  characters  given  above  will  enable  a  Pompilid  to  be 
recognised  with  approximate  certainty.  The  elongation  of  the 
hind  legs  includes  all  the  parts,  so  that  while  the  femur  extends 
nearly  as  far  back  as  the  extremity  of  the  body — in  dried 
examples  at  any  rate — the  tibiae  and  the  long  tarsi  extend  far 
beyond  it  ;  thus  these  Insects  have  great  powers  of  running  ;  they 
are  indeed  remarkable  for  extreme  activity  and  vivacity.  They 
may  frequently  be  seen  running  rapidly  on  the  surface  of  the 
ground,  with  quivering  wings  and  vibrating  antennae,  and 
are  probably  then  employed  in  the  search  for  prey,  or  some  other 
of  the  operations  connected  with  providing  a  store  of  food  for 
their  young.  Spiders  appear  to  be  their  special,  if  not  their  only, 
prey.  Several  authors  have  recorded  details  as  to  the  various 
ways  in  which  the  prey  is  attacked.  Fabre  has  observed  the 
habits  of  several  species,  and  we  select  his  account  of  the  modus 
operandi  of  species  of  the  genera  Pompilus  and  Calicurgus,  in 
their  attacks  on  poisonous  spiders  that  inhabit  holes  in  the 
ground  or  in  walls.  The  wasp  goes  to  the  mouth  of  the  spider's 
burrow,  and  the  latter  then  dashes  to  the  entry,  apparently 


102 


HYMENOPTERA 


CHAP. 


enraged  at  the  audacity  of  its  persecutor.  The  Calicurgus  will 
not  actually  enter  a  burrow  when  there  is  a  spider  in  it, 
because  if  it  did  so  the  spider  would  speedily  dispose  of  the 
aggressor  by  the  aid  of  its  poisonous  fangs.  The  Calicurgus, 
therefore,  has  recourse  to  strategy  with  the  object  of  getting 
the  spider  out  of  its  nest ;  the  wasp  seizes  its  redoubtable 

foe  by  one  foot  and  pulls ; 
probably  it  fails  to  extract 
the  spider,  and  in  that  case 
rapidly  passes  to  another 
burrow  to  repeat  its  tactics ; 
sooner  or  later  a  spider  is 
in  some  moment  of  inatten- 
tion or  incapacity  dragged 
from  its  stronghold,  and, 
being  then  comparatively 
helpless,  feels  itself  at  a 
disadvantage  and  offers  but  a 
feeble  resistance  to  the  wasp, 
which  now  pounces  on  its 
body  and  immediately  in- 
flicts a  sting  between  the 
fangs  of  the  foe,  and  thus 
at  once  paralyses  these  dangerous  weapons  ;  thereafter  it  stings 
the  body  of  the  spider  near  to  the  junction  of  the  abdomen  and 
cephalothorax,  and  so  produces  complete  inactivity.  Having 
secured  its  prey,  the  wasp  then  seeks  a  suitable  hole  in  which 
to  deposit  it ;  probably  an  empty  burrow  of  a  spider  is  selected 
for  the  purpose,  and  it  ma.y  be  at  a  height  of  several  feet  in  a 
wall  ;  the  Hymenopteron,  walking  backwards,  drags  its  heavy 
prey  up  the  wall  to  bring  it  to  the  den.  When  this  is  accom- 
plished an  egg  is  deposited  on  the  spider,  and  the  wasp  goes 
in  search  of  a  fragment  or  two  of  mortar,  with  winch  the  mouth 
of  the  burrow  is  finally  blocked.  Fabre's  accounts  refer  to  the 
habits  of  several  species,  and  give  a  good  insight  into  some  points 
of  the  instincts  of  both  the  spider  and  the  wasp.  It  seems  that  a 
sense  of  superiority  is  produced  in  one  or  other  of  the  foes,  accord- 
ing as  it  feels  itself  in  suitable  conditions  ;  so  that  though  a  spider 
out  of  its  burrow  and  on  the  ground  is  speedily  vanquished  by  the 
1'oiupilid,  yet  if  the  two  be  confined  together  in  a  vase,  both  are 


FIG.  43. — Calicurgus  hyalinatus  ?.     Britain. 


ill  POMPILIDAE  103 

shy  and  inclined  to  adopt  defensive  or  even  evasive  tactics,  the 
result  probably  being  that  the  wasp  will  be  killed  by  the  spider 
during  the  night,  that  being  the  period  in  which  the  attacking 
powers  of  the  spider  are  more  usually  brought  into  play. 

It  seems  to  be  the  habit  of  some  Pompilus  to  procure  a  victim 
before  they  have  secured  a  place  for  its  reception  ;  and  Fabre  took 
advantage  of  this  fact,  and  made  very  interesting  observations  on 
some  points  of  the  instinct  of  these  wasps.  Having  found  a 
Pompilus  that,  after  having  caught  a  spider  and  paralysed  it, 
was  engaged  in  making  a  retreat  for  its  reception,  he  abstracted 
the  booty,  which  was  deposited  at  the  top  of  a  small  tuft  of 
vegetation  near  to  where  the  Pompilus  was  at  work.  In  this 
case  the  burrow  in  course  of  preparation  was  subterranean,  and 
was  formed  by  the  Pompilus  itself,  which  therefore  could  not, 
while  it  was  engaged  underground,  see  what  took  place  near  it. 
It  is  the  habit  of  the  wasp  to  leave  its  work  of  excavation  from 
time  to  time,  and  to  visit  the  prey  as  if  to  assure  itself  of  the 
safety  of  this  object,  and  to  enjoy  the  satisfaction  of  touching  it 
with  the  mouth  and  palping  it.  Desirous  of  testing  the  wasp's 
memory  of  locality,  Fabre  took  the  opportunity,  while  the  Insect 
was  working  at  the  formation  of  its  burrow,  of  removing,  as  we 
have  said,  the  booty  from  the  place  where  it  had  been  deposited, 
and  putting  it  in  another  spot  some  half-yard  off.  In  a  short 
time  the  Pompilus  suspended  work  and  went  straight  to  the  spot 
where  it  had  deposited  its  property,  and  finding  this  absent, 
entered  on  a  series  of  marches,  counter-marches,  and  circles  round 
the  spot  where  it  had  left  the  prey,  as  if  quite  sure  that 
this  was  really  the  place  where  the  desired  object  ought  to  be. 
At  last  convinced  that  the  paralysed  prey  was  no  longer  where 
it  had  been  placed,  the  Pompilus  made  investigations  at  a  greater 
distance  and  soon  discovered  the  spider.  Fabre  recounts  that  its 
movements  then  appeared  to  indicate  astonishment  at  the  change 
of  position  that  it  thus  ascertained  to  have  occurred.  The  wasp, 
however,  soon  satisfied  itself  that  this  was  really  the  very 
object  it  was  seeking,  and  seizing  the  spider  by  the  leg  slightly 
altered  its  position  by  placing  it  on  the  summit  of  a  small  tuft 
of  vegetation ;  this  latter  proceeding  being  apparently  always 
carried  out  by  this  species  of  Pompilus.  Then  it  returned  to  its 
excavation,  and  Fabre  again  removed  the  spider  to  a  third  spot ; 
the  wasp  when  it  next  rested  from  its  work  made  its  way 


104  HYMENOPTERA  CHAP. 

immediately  to  the  second  spot,  where  it  had  last  left  the  spider, 
thus  showing  that  it  possessed  an  accurate  memory  for  locality ; 
the  wasp  was  very  much  surprised  at  the  absence  of  the  valued 
prize  and  persisted  in  seeking  it  in  the  immediate  vicinity  with- 
out once  returning  to  the  place  where  it  had  been  first  located. 
Fabre  repeated  this  manoeuvre  five  times,  and  the  Pompilus 
invariably  returned  at  once  to  the  spot  where  it  had  last  left  its 
prey.  The  acute  memory  for  localities  displayed  by  this  Insect 
seems  to  be  more  or  less  general  throughout  the  Aculeate 
Hymenoptera,  and  is  of  very  great  importance  to  them.  The 
power  of  finding  the  object  appears  to  depend  on  sight,  for  when 
Fabre,  after  removing  the  spider  to  a  fresh  spot,  made  a  slight 
depression  in  the  ground,  placed  the  spider  in  it  and  covered  it 
over  with  a  leaf,  the  wasp  did  not  find  it.  At  the  same  time,  the 
Insect's  sight  must  be  a  very  different  sense  from  our  own,  for  the 
wasp,  when  seeking  its  lost  booty,  frequently  passed  within  a  couple 
of  inches  of  it  without  perceiving  it,  though  it  was  not  concealed. 

Belt  gives  an  example  of  the  habits  of  the  Mexican  Pompilus 
2^olistoides.  He  noticed  it,  when  hunting  for  spiders,  make  a  dart 
at  a  web  in  the  centre  of  which  a  spider  was  stationed ;  by  this 
movement  the  creature  was  frightened  and  fell  to  the  ground, 
where  it  was  seized  by  the  wasp  and  stung.  The  Pompilus  then 
dragged  its  prisoner  up  a  tree  and  afterwards  Hew  off  with  it, 
the  burden  being  probably  too  heavy  for  conveyance  to  the  nest 
without  the  vantage  of  an  elevation  to  start  from. 

Several  modifications  adopted  by  Pompilidae  in  their  mode  of 
stinging  their  spider- victims  have  been  recorded  by  Ferton  ;  these 
we  cannot  allude  to  in  detail,  but  will  nevertheless  mention  that 
one  species  stings  the  body  of  its  spider-prey  at  random,  and 
that  in  other  cases  it  would  appear  that  the  paralysis  of  the 
spider  is  evanescent.  In  short,  there  are  various  degrees  of 
perfection  in  the  details  of  the  art  of  stinging. 

The  most  remarkable  of  the  forms  of  Pompilidae  are  the 
numerous  species  of  Pe^)sis,  a  genus  peculiar  to  America,  whence 
upwards  of  200  species  are  already  known.1  Some  of  them 
;iltain  a  length  of  two  inches  or  more,  and  are  able  to  conquer 
the  largest  spiders ;  even  the  formidable  Mygale  avicularis 
succumbs  to  their  agility  and  skill.  Some  of  these  Pepsis  have 
beautifully  coloured  wings ;  according  to  Cameron,  this  may  be 

1  Monograph  by  Lucas,  Berlin  ent.  Zcitsclir.  xxxix.  1894. 


in  POMPILIDAE  IO5 

due  to  scales.  P.  formosus,  Say,  is  called  in  Texas  the  tarantula- 
killer  ;  according  to  Buckley,  its  mode  of  attack  on  the  huge 
spider  is  different  from  that  made  use  of  by  its  European  ally. 
When  it  discovers  a  tarantula  it  flies  "  in  circles  in  the  air, 
around  its  victim.  The  spider,  as  if  knowing  its  fate,  stands  up 
and  makes  a  show  of  fighting,  but  the  resistance  is  very  feeble 
and  of  no  avail.  The  spider's  foe  soon  discovers  a  favourable 
moment  and  darts  upon  the  tarantula,  whom  it  wounds  with  its 
sting,  and  again  commences  flying  in  circles."  The  natural 
retreat  of  this  huge  spider,  Mygale  hentzii,  is  in  holes  in  the 
ground,  and  this  account  does  not  inform  us  whether  the  spider 
allows  itself  to  be  overcome  when  in  its  nest,  or  is  only  attacked 
when  out  of  its  retreat. 

The  genus  Mygnimia  includes  a  very  large  number  of  species, 
and  has  a  wider  geographical  distribution  than  Pcpsis,  being 
found  in  the  tropical  regions  of  both  the  Old  and  New  Worlds, 
some  of  them  rivalling  in  size  and  ferocity  the  larger  specimens 
of  the  genus  Pcpsis.  In  the  Insects  of  this  genus  there  is  usually 
a  more  or  less  distinct  small  space  of  more  pallid  colour  on  the 
middle  of  each  front  wing.  Parcqiompilus  is  a  curious  genus 
consisting  of  Insects  of  a  great  variety  of  peculiar  coloration, 
and  having  the  wings  short,  so  as  to  be  of  little  vise  for  flight. 
P.  gravesii  is  an  inhabitant  of  Chili. 

Agenia  carbonaria  and  A.  liyalipennis  are  small  and  feeble 
Insects  inhabiting  the  south  of  Europe.  A.  carbonaria  extends  to 
the  south  of  England.  They  construct,  as  nests  for  their  offspring, 
small  earthenware  vessels,  differing  in  form  according  to  the 
species,  those  of  A.  liycdipennis  being  vase-like  in  shape,  while 
those  of  A.  carbonaria  are  contracted  near  the  mouth,  something 
after  the  fashion  of  a  wide-mouthed  bottle.  The  Insect  is  able 
by  some  means — Fabre  thinks  by  the  use  of  saliva — to  varnish 
the  •  interior  of  the  vessel  so  that  it  will  not  absorb  water ;  the 
outside  of  the  cells  is,  however,  not  so  protected,  and  speedily 
crumbles  away  when  exposed  to  the  action  of  water ;  hence  the 
vessel  is  placed  in  a  protected  situation,  such  as  in  a  tree-stump, 
or  a  hole  in  a  wall,  or  even  in  an  empty  snail-shell  under  a  heap 
of  stones.  The  cells  are  stored  with  spiders  that  have  been 
paralysed  by  stinging  and  that  serve  as  food  for  the  larva  of  the 
Agenia.  The  larva  of  A.  carbonaria  has  been  described,  and 
some  particulars  as  to  its  habits  have  been  given  by  Verhoeff. 


106  HYMENOPTERA 


CHAP. 


It  has  been  stated  that  this  wasp  does  not  paralyse  its  prey 
by  stinging,  but  substitutes  a  process  of  biting  to  prevent  the 
spider  from  hurting  the  larva  that  is  to  feed  on  it ;  and  Verhoeff  's 
observations  seem  to  show  that  the  legs  of  the  spider  are  broken 
by  some  proceeding  of  the  kind.  The  Agenia  larva  is  of  peculiar 
shape,  the  head  not  being  innexed,  while  the  pleurae  of  each 
segment,  from  the  second  onwards,  are  prominent,  so  as  to  give 
the  outline  of  the  body  a  scalloped  appearance.  This  larva  is 
much  infested  by  an  Ichneumon  that  devours,  it  appears,  not 
only  the  larva  itself,  but  also  the  spider  that  was  destined  to  be 
food  for  the  larva.  Verhoeff  seems  to  have  found  some  evidence 
that  Pompilus  sericeus  may  also  be  a  parasite  on  the  Agenia. 

The  construction  of  earthenware  cells,  instead  of  the  burrows 
usual  in  Pompilidae,  by  the  species  of  this  genus  is  one  of  the 
cases  alluded  to  in  our  introductory  remarks  as  to  allied  Fossores 
exhibiting  different  habits.  Mr.  Pride  has  recently  sent  us  from 
Brazil  similar  earthen  vessels  constructed  by  some  Pompilid. 

The  habits  of  Pompilids  of  the  genus  Ceropales  are  analogous  to 
those  of  the  parasitic  bees.  Perez  has  recently  given  us  information 
as  to  a  very  curious  form  of  parasitism  in  this  genus  ;  he  says  that 
when  a  Pompilus  has  obtained  a  spider  as  provision  for  its  young, 
it  is  pursued  by  a  Ceropales,  which  lays  an  egg  un  the  spider,  thus 
as  it  were  substituting  in  advance  its  own  young  for  that  of  the 
Pompilus.  Information  as  to  the  subsequent  course  of  events  in 
this  case  is  not  at  present  forthcoming.  In  another  case  a 
Ceropales  was  observed  to  oviposit  on  the  spider,  not  while  this 
is  being  carried  in,  but  subsequently  by  entering  the  nest  for  the 
purpose ;  a  habit  quite  similar  to  that  of  some  parasitic  bees. 
Ferton  has  recently  made  the  unexpected  discovery  that  some 
Pompilus  act  as  robbers ;  one  individual  taking  away  by  force  the 
spider  that  another  has  captured  and  is  carrying  off. 

Lichtenstein  described  a  Pompilid  larva,  that  he  afterwards 
ascertained  to  be  Calicurgus  lii/nli nutus,  as  possessing  the  extra- 
ordinary habit  of  feeding  as  an  external  parasite  fixed  to  the 
dorsal  surface  of  a  spider ;  thus  repeating,  it  would  appear,  the 
liabits  of  some  of  the  Ichnemonidae,  though  the  perfect  Insect 
(Fig.  143)  does  not  differ  in  structure  from  its  congeners. 
Emery  has  given  an  account  of  some  Pompilids  that  do  not 
bury  their  prey,  but  after  stinging  it  and  depositing  an  egg, 
simply  leave  the  spider  on  the  spot, 


in  FOSSORES — SPHEGIDAE — SPHEGIDES  IO/ 

Buller  has  described  the  habits  of  a  Pompilid  in  New  Zealand  ; 
his  account  is  interesting  because  it  shows  a  remarkable  similarity 
in  the  proceedings  of  this  antipodean  wasp  to  those  of  its  con- 
geners on  our  own  side  of  the  world.  The  species  is  not 
scientifically  named,  but  it  appears  that  it  is  known  in  New 
Zealand  as  "  the  Mason-bee."  It  forms  a  nest  of  yellow  clay 
consisting  apparently  of  about  eight  cells,  each  of  which  is  filled 
with  one  or  more  spiders  in  a  paralysed  condition.  The  figure 
given  of  the  larva  of  this  Insect  by  Buller  shows  it  to  possess  a 
peculiarly  formed  head. 

It  is  pleasing  to  find  that  Pompilidae  do  not  make  use  of  cruel 
methods  when  others  will  serve  their  purpose.  We  are  informed 
that  a  large  Australian  Pompilid — Priocnemis  bicolor — may  find 
a  Cicada  sucking  sap  from  a  hole  it  has  pierced  in  a  tree.  The 
Priocnemis  has  not  the  art  of  making  the  puncture  necessary  to 
procure  sap,  so  the  wasp  seizes  the  Cicada,  and  shakes  it  till 
it  leaves  its  hold  and  flies  away,  when  the  Priocnemis  takes  its 
place  and  sips  the  sap.  It  is  added  that  the  wasp  never  hurts 
the  Cicada. 

Fam.  3.  Sphegidae. 

Pronotum  free  from  the  tegulae ;  when  the  stigmatic  lobes  extend  as 
far  back  as  the  wing -insertion,  they  are  placed  below  it  and 
separated  l>y  a  space  from  it. 

This  large  assemblage  of  Fossores  is  the  one  about  which  the 
greatest  difference  of  opinion  prevails.  It  is  based  entirely  on 
the  prothoracic  characters  mentioned  above,  and  cannot  be  looked 
on  as  natural.  We  shall,  however,  follow  Kohl x  in  treating  for 
the  present  as  only  one  family  the  divisions  considered  by  many 
as  distinct  families.  They  are  ten  in  number. 

Sub-Fam.  1.  Sphegides. — Hind  body  with  a  slender  pedicel  of 
variable  length  ;  two  spurs  on  the  middle  tibia.  The  pro- 
podeum  usually  horizontally  elongate? 

This  group  includes  a  great  number  of  species,  about  200  of 
which  are  referred  to  the  genus  Sphex. 

1  "Die  Gattungen  der  Sphegiden, "  Ann.  Hofmus.   Wicn.  xi.  1896,  pp.  233-596. 
Seven  plates. 

2  We  will  take  this  opportunity  of  correcting  an  error  in  the  explanation  of  Fig. 
333  of  the  preceding  volume,  showing  the  propodeum,  etc.  of  Sphex  chrysis.   f  points 
to  a  division  of  the  mesonoturn,  not  of  the  metanotum,  as  there  stated. 


IO8  HVMENOPTERA 


CHAP. 


The  habits  of  one  species  of  this  genus  have  been  fully  de- 
scribed by  Fabre ;  he  assigns  to  the  species  the  name  of  S.  flavi- 
pennis,  but  Kohl  considers  that  it  is  more  probably  S.  maxillosus. . 
This  Insect  forms  its  nests,  in  the  South  of  France,  in  the  ground, 
excavating  a  main  shaft  with  which  are  connected  cells  intended 
for  the  reception  of  the  provisions  for  the  young.  The  entrance 
to  the  burrow  is  formed  by  piercing  a  hole  in  the  side  of  a  very 
slight  elevation  of  the  soil.  Thus  the  entrance  to  the  construc- 
tion consists  of  a  horizontal  gallery,  playing  the  part  of  a  vesti- 
bule, and  this  is  used  by  the  Sphcx  as  a  place  of  retreat  and 
shelter  for  itself;  at  the  end  of  the  vestibule,  which  may  be  two 
or  three  inches  long,  the  excavation  takes  an  abrupt  turn  down- 
wards, extending  in  this  manner  another  two  or  three  inches, 
and  terminating  in  an  oval  cell  the  larger  diameter  of  which  is 
situate  in  a  horizontal  plane.  When  this  first  cell  has  been  com- 
pleted, stored  with  food,  and  an  egg  laid  in  it,  the  entrance  to 
it  is  blocked  up,  and  another  similar  cell  is  formed  on  one  side ; 
a  third  and  sometimes  a  fourth  are  afterwards  made  and  pro- 
visioned, then  the  Insect  commences  anew,  and  a  fresh  tunnel  is 
formed  ;  ten  such  constructions  being  the  number  usually  prepared 
by  each  wasp.  The  Insect  works  with  extreme  energy,  and  as 
the  period  of  its  constructive  activity  endures  only  about  a  month, 
it  can  give  but  two  or  three  days  to  the  construction  and  pro- 
visioning of  each  of  its  ten  subterranean  works.  The  provisions, 
according  to  Fabre,  consist  of  a  large  species  of  field-cricket,  of 
which  three  or  four  individuals  are  placed  in  each  cell.  Kohl 
states,  however,  that  in  Eastern  Europe  an  Insect  that  he 
considers  to  be  the  same  species  as  Fabre's  Spliex,  makes  use  of 
locusts  as  provisions,  and  he  thinks  that  the  habit  may  vary 
according  to  the  locality  or  to  the  species  of  Orthoptera  that 
may  be  available  in  the  neighbourhood.  However  that  may 
be,  it  is  clear  from  Fabre's  account  that  this  part  of  the 
^l>]iexs  duties  do  not  give  rise  to  much  difficulty.  The  cricket, 
having  been  caught,  is  paralysed  so  that  it  may  not  by  its 
movements  destroy  the  young  larva  for  whose  benefit  it  is 
destined.  The  Sphex  then  carries  it  to  the  burrow  to  store  it  in 
one  of  the  cells;  before  entering  the  cell  the  Insect  is  in  the 
habit  of  depositing  its  prey  on  the  ground,  then  of  turning  round, 
entering  the  burrow  backwards,  seizing  as  it  does  so  the  cricket 
by  the  antennae,  and  so  dragging  it  into  the  cell,  itself  going  back- 


.  in  SPHEGIDAE SPHEGIDES  IOQ 

wards.  The  habit  of  depositing  its  prey  on  the  ground  enabled 
Fabre  to  observe  the  process  of  stinging ;  this  he  did  by  himself 
capturing  a  cricket,  and  when  the  wasp  had  momentarily  quitted 
its  prey,  substituting  the  sound  cricket  for  the  paralysed  one. 
The  Spliex,  on  finding  this  new  and  lively  victim,  proceeds  at 
once  to  sting  it,  and  pounces  on  the  cricket,  which,  after  a  brief 
struggle,  is  overcome  by  the  wasp  ;  this  holds  it  supine,  and  then 
administers  three  stings,  one  in  the  neck,  one  in  the  joint  between 
the  pro-  and  meso-thorax,  and  a  third  at  the  base  of  the  abdomen, 
these  three  spots  corresponding  with  the  situation  of  the  three 
chief  nervous  centres  governing  the  movements  of  the  body. 
The  cricket  is  thus  completely  paralysed,  without,  however,  being- 
killed.  Fabre  proved  that  an  Insect  so  treated  would  survive  for 
several  weeks,  though  deprived  of  all  power  of  movement. 
Three  or  four  crickets  are  placed  by  the  wasp  in  each  cell,  100 
individuals  or  upwards  being  thus  destroyed  by  a  single  wasp. 
Although  the  sting  has  such  an  immediate  and  powerful  effect 
on  the  cricket,  it  occasions  but  a  slight  and  evanescent  pain  to  a 
human  being ;  the  sting  is  not  barbed,  as  it  is  in  many  bees  and 
true  wasps,  and  appears  to  be  rarely  used  by  the  Insect  for  any 
other  purpose  than  that  of  paralysing  its  victims.  The  egg  is 
laid  by  the  Spliex  on  the  ventral  surface  of  the  victim  between 
the  second  and  third  pairs  of  legs.  In  three  or  four  days  the 
young  larva  makes  its  appearance  in  the  form  of  a  feeble  little 
worm,  as  transparent  as  crystal ;  this  larva  does  not  change  its 
place,  but  there,  where  it  was  hatched,  pierces  the  skin  of  the 
cricket  with  its  tiny  head,  and  thus  begins  the  process  of  feed- 
ing ;  it  does  not  leave  the  spot  where  it  first  commenced  to  feed, 
but  gradually  enters  by  the  orifice  it  has  made,  into  the  interior 
of  the  cricket.  This  is  completely  emptied  in  the  course  of 
six  or  seven  days,  nothing  but  its  integument  remaining ;  the 
wasp-larva  has  by  this  time  attained  a  length  of  about  1 2  milli- 
metres, and  makes  its  exit  through  the  orifice  it  entered  by,  chang- 
ing its  skin  as  it  does  so.  Another  cricket  is  then  attacked  and 
rapidly  consumed,  the  whole  stock  being  devoured  in  ten  or  twelve 
days  from  the  commencement  of  the  feeding  operations  ;  the  con- 
sumption of  the  later-eaten  crickets  is  not  performed  in  so  delicate 
a  manner  as  is  the  eating  of  the  first  victim.  When  full-grown, 
the  process  of  forming  a  cocoon  commences :  this  is  a  very  ela- 
borate operation,  for  the  encasement  consists  of  three  layers,  in 


I  I O  HVMENOPTERA  CHAP. 

addition  to  the  rough  silk  that  serves  as  a  sort  of  scaffolding  on 
the  exterior  :  the  internal  coat  is  polished  and  is  of  a  dark  colour, 
owing  to  its  being  coloured  with  a  matter  from  the  alimentary, 
canal :  the  other  layers  of  the  cocoon  are  white  or  pale  yellow. 
Fabre  considers  that  the  outer  layers  of  the  cocoon  are  formed 
by  matter  from  the  silk-glands,  while  the  interior  dark  coat  is 
furnished  by  the  alimentary  canal  and  applied  by  the  mouth  of 
the  larva :  the  object  of  this  varnish  is  believed  to  be  the  exclu- 
sion of  moisture  from  the  interior  of  the  cocoon,  the  subterranean 
tunnels  being  insufficient  for  keeping  their  contents  dry  through- 
out the  long  months  of  winter.  During  the  whole  of  the  pro- 
cess of  devouring  the  four  crickets,  nothing  is  ejected  from  the 
alimentary  canal  of  the  larva,  but  after  the  cocoon  is  formed 
the  larva  ejects  in  it,  once  for  all,  the  surplus  contents  of  the 
intestine.  Nine  months  are  passed  by  the  Insect  in  the  cocoon, 
the  pupal  state  being  assumed  only  towards  the  close  of  this 
period.  The  pupa  is  at  first  cpuite  colourless,  but  gradually 
assumes  the  black  and  red  colour  characteristic  of  the  perfect 
wasp.  Fabre  exposed  some  specimens  of  the  pupa  to  the  light 
in  glass  tubes,  and  found  that  they  went  through  the  pupal  meta- 
morphosis in  just  the  same  manner  as  the  pupae  that  remained  in 
the  darkness  natural  to  them  during  this  stage  of  their  existence. 
Sphex  coendetis  is  frequently  stated  to  have  the  habit  of  pro- 
visioning its  nests  with  both  Orthoptera  and  Spiders;  but  Kohl 
considers  with  reason  that  this  record  is,  as  regards  spiders,  a 
mistake,  arising  probably  from  a  confusion  with  some  other 
Insect  of  similar  appearance,  such  as  Pelopacus  (Sceliphron) 
coendcus.  S.  coeridcus  is  no  doubt  the  same  as  S.  (Chlorion) 
Inlmtt/s,  which  Eothney  observed  in  East  India,  provisioning  its 
nests  with  Orthoptera.  He  discovered  a  nest  in  process  of  con- 
struction, and  during  the  absence  of  the  mother-wasp  abstracted 
from  the  burrow  a  large  field-cricket  that  she  had  placed  in  it ; 
he  then  deposited  the  Orthopteron  near  the  cell ;  the  parent 
X/i/K'.i-  on  returning  to  work  entered  the  tunnel  and  found  the 
provision  placed  therein  had  disappeared  ;  she  came  out  in  a  state 
of  excitement,  looked  for  the  missing  cricket,  soon  discovered  it, 
submitted  it  to  the  process  of  malaxation  or  kneading,  and  again 
placed  it  in  the  nest,  after  having  cleared  it  from  some  ants 
that  had  commenced  to  infest  it.  She  then  disappeared,  and 
Itothney  repeated  the  experiment ;  in  due  course  the  same  series 


in  SPHEGIDAE — SPHEGIDES  I  I  I 

uf  operations  was  performed,  and  were  repeated  many  times,  the 
Sphex  evidently  acting  in  each  case  as  if  either  the  cricket  had 
disappeared  owing   to  its  being  incompletely   stunned,  or  to   its 
having  been  stolen  by  ants.      Finally,  the  observer  placed  the 
cricket  at  a  greater  distance  from  the  nest,  when  it  recovered 
from  the  ill-treatment  it  had  received  sufficiently  to  make  its 
escape.      The  points  of  interest  in  this  account  are  the  fact  that 
the  cricket  was  only  temporarily  paralysed,  and   that   the   wasp 
was  quite  able  to  cope  with  the  two  special  difficulties  that  must 
frequently  occur  to  the  species  in  its  usual  round  of  occupations. 
The  genus  Ammophila  is  of  wide  distribution,  and  its  species 
make  vertical  tunnels  in  the  ground.      The  habits  of  some  of  the 
species  found  in   France  have    been   described    by  Fabre.      The 
Insect  does  not  inhabit    the  burrow  while  it  is  in    process  of 
formation,  but  quits   it ;   and   some   of  the   species   temporarily 
close    the    entry    to    the   incomplete    nest    with    a   stone.      The 
tunnel  is  a   simple  shaft  with  a  single  cell  at  its  termination  ; 
this  is  stored  with  caterpillars,  the  different  species  of  Ammo- 
phila selecting  different  grubs  for  the  purpose.      A.  liirsuta  hiber- 
nates in  the  perfect  state,  and  carries  on  its  work  in   the  spring ; 
it  chooses  a    single  larva  of  considerable  size  belonging  to  one 
of  the  nocturnal  Lepidoptera,  and  this  it  paralyses  by  a  series  of 
about  nine  stings,  of  which   one  is  implanted  in  each   segment 
from  the  first  thoracic  ring  backwards  ;  it  forms  the  burrow  only 
after  the  food   to  be    placed   therein   lias   been   obtained.      The 
caterpillar  used  is  subterranean  in  habit,  and   the  Ammophila 
detects  the  larva  by  some  sense,  the  nature  of  which  appears  at 
present  quite  uncertain.      A.  holosericea  chooses  smaller  larvae  of 
the  family  Geometridae,  and  uses  only  one  or  two  stingings  to 
paralyse  each  larva ;  several  caterpillars  are  used  to  provision  a 
single  cell,  and  they  are  often  selected  of  different  colours. 

Marchal  has  also  published  an  important  account  of  the 
proceedings  of  A.  ajfinis ;  he  confirms  Fabre's  observations,  and 
even  adds  to  their  interest  by  suggesting  that  the  Ammophila 
administers  special  stings  for  the  purpose  of  paralysing  the 
mandibles  of  the  caterpillar  and  depriving  it  of  any  power  of 
afterwards  injuring  the  larva  that  will  feed  on  it.  He  thinks 
the  motliQT-Ammojyhila  herself  profits  by  appropriating  an  exuda- 
tion from  the  victim. 

Some  species  of  Sphegides  have  the  curious  habit  of  choosing 


112  HYMENOPTERA  CHAP. 

the  interiors  of  human  habitations  as  the  spots  most  suitable  for 
the  formation  of  their  own  domestic  establishments.  Fabre  has 
given  a  charming  account  of  the  habits  of  Pelopaeus  (Sceliphron} 
spirifex,  a  species  that  inhabits  the  South  of  Europe,  and  that  forms 
its  nests  in  the  cottages  of  the  peasants.  The  spot  usually  selected 
is  a  nook  in  the  broad,  open  fireplace,  out  of  reach  of  the  names, 
though  not  of  the  smoke ;  here  the  Pelopaeus  forms  a  nest  of 
earth,  consisting  of  ten  to  fifty  cells,  the  material  being  mud  or 
clay  brought  in  little  balls  by  the  aid  of  the  Insect's  mandibles  ; 
about  twenty  visits  are  required  in  order  to  complete  one  cell,  so 
that  for  the  construction  of  a  large  nest  of  fifty  cells,  about  one 
thousand  visits  must  be  made  by  the  Insect.  It  flies  in  and 
out  of  the  house  apparently  not  at  all  incommoded  by  the 
human  habitants,  or  by  the  fact  that  the  peasant's  potage  may 
be  simmering  on  the  fire  quite  close  to  where  the  fearless  little 
creature  is  carrying  on  its  architectural  operations.  The  cells 
are  stored  with  spiders,  of  which  the  wasp  has  to  bring  a  plentiful 
supply,  so  that  its  operations  extend  over  a  considerable  period. 
The  prey  is  captured  by  the  Pelopaeus  whilst  on  the  wing,  and 
carried  off  at  once,  being  probably  stung  by  the  wasp  during 
the  process  of  transit ;  apparently  it  is  killed  by  the  operation, 
not  merely  paralysed.  Only  small  spiders  are  taken  by  this 
species,  and  the  larva  of  the  Pelopaeus  consumes  them  in  a  short- 
time,  one  by  one,  before  the  process  of  decomposition  sets  in  ; 
the  egg,  too,  is  laid  on  the  first  spider  introduced,  and  this  is  of 
course  at  the  bottom  of  the  cell,  so  that  the  spiders  are  eaten  by 
the  wasp's  larva  in  the  order  in  which  they  were  brought  to  the 
cell.  The  cell  is  sealed  up  when  full,  the  number  of  spiders 
placed  in  it  being  on  the  average  about  eight.  The  larva 
completes  its  task  of  consuming  the  store  in  about  ten  days,  and 
then  forms  a  cocoon  for  its  metamorphosis.  TWTO  or  thivr 
generations  are  produced  in  a  single  year,  the  autumnal  one 
passing  eight  or  nine  months  in  the  clay  cells,  which  are  lodged 
in  a  nook  of  the  peasant's  hearth,  and  exposed  to  the  smoke  of 
his  fire  during  all  the  months  of  winter.  Pelopae.us  (Scdipliroti) 
is  a  genus  including  many  species ; *  several  of  them  are  known 

1  Pelopaeus  disappears  from  the  new  catalogue  of  Hymenoptera  as  the  name  of  a 
valid  genus;  its  species  being  assigned  to  ,sv/7/y>A/-n//  \\\\<\  various  other  genera. 
We  have  endeavoured,  as  regards  this  name,  to  reconcile  the  nomenclature  of 
previous  authors  with  that  used  in  the  new  catalogue  by  placing  the  generic  name 
adopted  in  the  latter  in  brackets. 


in  SPHEGIDAE SPHEGIDES PELOPAEUS  113 

to  be  specially  .attached  to  the  habitations  of  human  beings. 
Both  has  given  an  account  of  the  habits  of  P.  (Scelipliron} 
laetus  in  Australia ;  he  says  that  in  some  parts  it  is  very 
difficult  to  keep  these  wasps  out  of  the  houses ;  the  nest  is 
formed  of  mud,  and  constructed  on  the  furniture  or  in  any  part 
of  a  room  that  suits  the  fancy  of  the  Insect.  This  it  must  be 
admitted  is,  according  to  human  ideas,  liable  to  the  charge  of 
being  very  capricious.  Both  timed  a  wasp  building  its  nest, 
and  found  that  it  brought  a  fresh  load  of  mud  every  two  or 
three  minutes.  If  the  wasp  be  allowed  to  complete  the  nest 
undisturbed,  she  does  so  by  adding  to  the  exterior  diagonal 
streaks  of  mud,  so  giving  to  the  nest  the  look  of  a  small  piece 
of  the  bark  of  a  common  acacia.  The  construction  consists  of 
from  ten  to  twenty  cells,  and  when  completed  is  provisioned 
with  spiders  for  the  use  of  the  young.  This  wasp  is  much 
pestered  by  parasites,  some  of  which  prevent  the  development  of 
the  larvae  by  consuming  the  spiders  intended  by  the  mother- 
wasp  for  its  young.  A  fly,  of  the  Order  Diptera,  is  said  to  follow 
the  wasp  when  carrying  a  spider,  and  to  deposit  also  an  egg  on 
the  food :  as  the  Dipterous  larvae  have  more  rapid  powers  of 
assimilation,  the  Pelopaeus  larvae  are  starved  to  death  ;  and  their 
mildewed  remains  may  be  found  in  the  cell,  after  their  enemies 
have  become  fully  developed  and  have  flown  away.  Another 
parasite  is  said  to  eat  the  wasp-larva,  and  attains  this  end  by 
introducing  an  egg  through  the  mud  wall  and  the  cocoon  of  the 
wasp — a  habit  that  seems  to  indicate  a  Leucospid  parasite. 
Tachytes  australis,  a  wasp  of  the  sub-family  Larrides  also  dis- 
possesses this  Pelopaeus  in  a  manner  we  shall  subsequently 
describe.  This  fragment  of  natural  history  from  Australia  has 
a  special  interest,  for  we  find  repeated  there  similar  complex 
biological  relations  to  those  existing  in  the  case  of  the  European 


congeners. 


P.  (SceUpliroti)  madraspcdanus  is  common  in  the  north-west 
provinces  of  Hindostan,  and  is  called  the  "  mud-dauber  "  by  the 
European  residents.  According  to  Home  it  constructs  its  cells  in 
the  oddest  places,  but  chiefly  about  the  inhabited  apartments  in 
houses.  It  is  perfectly  fearless  when  engaged  in  building :  the 
cells  are  four  to  six  in  number,  and  are  usually  provisioned  with 
spiders  to  the  number  of  about  twenty.  On  one  occasion 
it  was  observed  that  green  caterpillars  were  stored  instead  of 

VOL.   VI  T 


HYMENOPTERA 


CHAP. 


spiders.  The  species  is  said  to  be  protected  by  a  peculiar  odour 
as  well  as  by  its  sting ;  it  is  also  stated  that  it  disguises  its 
edifice  when  completed  by  making  it  look  like  a  dab  of  mud, 
and  on  one  occasion  "  rays  of  mud  were  observed  round  the  nest, 
even  more  exactly  imitating  a  lump  of  mud  thrown  with  some 
force."  P.  (Sceliphroii)  bilineatus,  formerly  thought  to  be  a  variety 
of  P.  'inadraspatanv-S,  builds  its  nests  in  hedges  and  trees. 

Sub-Fam.  2.  Ampulicides. — Prothorax  long  and  narrow. forming 
a  neck  in  front ;  chjpeus  beak-like ;  four  submarginal  cells, 
the  outer  one  being  complete ;  metathorax  elongate,  the  pos- 
terior part  of  the  metasternum  deeply  divided  to  allow  a 
perfect  inflection  of  the  abdomen. 

This  is  one  of  the  smallest  of  the  divisions  of  the  Sphegidae, 
but  has  a  very  wide  distribution,  being  represented  in  both 
the  Eastern  and  Western  Hemispheres.  It  is  allied  to  the 
Sphegides,  but  differs  by  the  prolongation  of  the  neck  and  of  the 
head,  and  by  the  articulation  between  the  petiole  and  thorax 
being  placed  on  the  under  surface  of  the  body ;  the  wing- 
nervures  are  said  to  be  of  inferior  importance  owing  to  their 

frequently  differing  in  indi- 
viduals of  the  same  species. 
These  Insects  appear  to  be 
rare  in  individuals,  as  well  as 
few  in  species,  and  but  little 
has  been  recorded  as  to  their 
habits ;  but  it  is  known  that 
they  live  on  cockroaches.  Per- 
kins has  given  a  brief  sketch 
of  the  habits  of  Ampulex  sibi- 
rica  that  is  of  great  interest, 
but  requires  confirmation.  He 
says  that  this  Insect,  in  West 
Africa,  enters  apartments  where 
cockroaches  abound,  and  attack- 
ing one,  that  may  probably  be 
Male.  four  times  its  own  size,  suc- 
ceeds, after  a  struggle,  in  sting- 
ing it;  the  cockroach  instantly  becomes  quiet  and  submissive,  and 
suffers  itself  to  lie  lei]  away  and  placed  in  confinement  in  some 


Fid.  4i.— Am/in/'  '•  cnmpressa. 
East  India. 


in  SPHEGIDAE AMPULICIDES  I  I  5 

spot  such  as  a  keyhole,  and  in  one  case  was  apparently  pre- 
vented from  afterwards  escaping,  by  the  wasp  carrying  some 
heavy  nails  into  the  keyhole.  The  larva  of  the  Ampulex  may 
be  presumed  to  live  on  the  Blattid,  as  it  is  added  that  dead 
bodies  of  the  cockroaches  are  frequently  found  with  the  empty 
cocoon  protruding  from  them.  This  account,  if  correct,  points  to 
some  features  in  the  habits  of  this  Insect  that  are  unique.  A 
remark  made  by  Eothney  in  reference  to  the  habits  of  A.  (Elii- 
nopsis)  rujicornis  seems  to  indicate  some  similar  instinct  on  the 
part  of  that  species  ;  he  says,  "  I  also  saw  two  or  three  of  these 
wasps  collar  a  peculiar  cockroach  by  the  antennae  and  lead  it  off 
into  a  crack  in  the  bark,  but  as  the  cockroach  reappeared  smiling 
each  time,  I  don't  know  what  was  up."  The  same  observer  records 
that  this  species  associates  with  Sima  rufonigra,  an  ant  it  greatly  re- 
sembles in  appearance,  as  well  as  with  a  spider  that  is  also  of  similar 
appearance  (Fig.  72).  Schurr  has  given  a  brief  account  of  the 
proceedings  of  Ampulex  compressa,  and  his  statements  also  tend 
to  confirm  the  correctness  of  Perkins'  report.  The  habits  of  a 
species  of  Ampulex  \vere  partially  known  to  Reaumur,  who 
described  them  on  the  authority  of  M.  Cossigni.  The  species  is 
believed  to  be  A.  compressa,  which  occurs  not  only  in  East  India, 
but  also  in  the  island  of  Bourbon,  the  locality  where  M.  Cossigni 
made  his  observation :  his  account  is,  like  the  others,  a  mere 
sketch  of  certain  points  observed,  the  most  important  of  which 
is  that  when  Ampidex  cannot  introduce  the  cockroach  into  a 
hole  that  it  has  selected  as  suitable,  it  bites  off  some  portions 
of  the  body  in  order  to  reduce  the  poor  Insect  to  the  necessary 
extent. 

From  these  fragmentary  observations  it  would  appear  that 
the  sting  of  the  Ampulex  has  not  so  powerful  a  paralysing  effect 
as  that  of  •  most  other  Fossores ;  and  that  the  Ampulex  does 
not  form  any  nest,  but  takes  advantage  of  suitable  holes  and 
crevices  to  store  the  victim  in  ;  also  that  it  displays  consider- 
able ingenuity  in  the  selection  of  materials  with  which  to  block 
up  the  cavity  in  which  it  has  placed  the  partially  incapacitated 
creature. 

The  genus  Dolicliurus  is  by  some  entomologists  considered 
the  type  of  a  sub-family  allied  to  the  Ampulicides ;  it  long 
consisted  of  a  small  and  rare  European  Insect,  but  some  exotic 
species  have  recently  been  added  to  it.  It  will  probably  prove  not 


Il6  HYMENOPTERA 


CHAP. 


sufficiently  distinct  from  Ampulicides,  although  the  pronotum  is 
much  shorter,  but  Handlirsch  has  recently  observed  that  the 
European  species  attacks  Blattidae  as  do  the  normal  Ampulicides  ; 
and  Ferton  has  recorded  that  D.  haeinorrhous  lives  at  the  expense 
of  Loloptera  deei/iicn*,  the  wasp  depositing  its  egg  on  the  left 
intermediate  femur  of  the  prey.  This  is  placed  in  a  solitary 
cell,  and  is  entirely  consumed  by  the  larva,  life  being  preserved 
till  within  a  few  hours  of  the  end  of  the  repast,  which  occupies 
altogether  eight  days. 

Sub-Fam.  3.    Larrides. — Hind  loch/    not   pt'<licell<itf,   or    with 
only  a  short  pedicel ;   one  spur  on  the  mi<l<ll>'  fi/n'n  ; 
inconspicuous.      Marginal  cell  of  the  front   wings 
culate,1  or  mandibles  excised  externally,  or  loth. 

This  group  is  by  some  writers  called  Tachy tides  instead  of 
Larrides,  as  owing  to  a  change  of  nomenclature  Txcliytcs  may  now 
be  considered  its  principal  genus.  It  is  in  connection  with 
this  and  the  neighbouring  sub -families  of  Sphegidae  that  some 
of  the  greatest  taxonomical  difficulties  exist.  We  include  in 
Larrides  the  "  Miscoplt  us  group  "  of  Kohl. 

The  species  of  the  genus  Tachy tes  seem  to  have  habits  very 
similar  to  those  of  the  genus  Sphex ;  they  form  shafts  in  the 
earth  and  provision  them  with  Orthoptera  ;  like  the  Spltex  and 
other  Fossores,  they  have  the  habit,  when  they  fly  to  their  tunnel 
with  a  victim,  of  depositing  it  for  a  short  time  on  the  ground 
close  to  the  mouth  of  the  burrow  while  they  turn  round  and 
enter  backwards ;  and,  after  doing  this  they  again  seize  their 
prey  and  drag  it  into  the  burrow.  Fabre  availed  himself  of  an 
opportunity  to  remove  the  prey  while  the  Hymenopteron  w;is 
entering  the  hole  alone ;  as  a  result  it  had  to  come  out  again  to 
seek  the  object ;  this  it  soon  found,  and  carried  to  the  hole, 
relinquishing  it  again  as  usual  while  it  turned  round ;  Fabre 
repeated  the  operation  several  times,  and  always  with  the  same 
result;  the  wasp,  though  it  might  have  kept  hold  of  the  victim 
while  it  turned,  and  thus  have  saved  itself  from  losing  the 
precious  object,  never  did  so. 

1  "When  a  second  cell  is  more  or  less  perfectly  marked  out,  the  cell  with  which 
it  is  connected  is  said  to  lie  appendiculate.  Tin-  nervnres  I'reijiiently  extend  beyond 
the  complete  cells  towards  the  outer  margin,  forming  "  incomplete  "  cells:  only 
complete  cells  are  counted,  except  when  "incomplete"  is  mentioned. 


Ill 


SPHEGIDAE —  LARRIDES 


117 


FIG.  45. — Tachytes  pectinipes  ?. 

Britain. 


One  species  of  Tachytes  in  the  south  of  France  selects  as  its  prey 
Orthoptera  of  the  family  Mantidae,  Insects  of  a  highly  ferocious 
disposition,  and  provided  with 
most  powerful  front  legs, 
capable  of  cutting  in  two  by 
a  single  act  the  body  of  an 
aggressor  like  the  Tachytes; 
the  latter  is,  however,  by  no 
means  dismayed  by  the  arms 
of  its  future  victim,  but  hover- 
ing above  the  latter  for  some 
time,  as  if  to  confuse  it,  and 
causing  it  repeatedly  to  turn 
its  very  mobile  head,  the 
Tacliytcs  at  last  pounces  down 
and  instantaneously  stings  the  Mantis  in  the  nerve  centre 
between  the  formidable  arms,  which  at  once  are  reduced  to  in- 
capacity ;  subsequently  the  Tachytes  paralyses  each  of  the  other 
pairs  of  legs,  and  then  carries  off  its  victim. 

Larra  anathema  chooses  mole-crickets  as  the  viand  for  its 
young,  and  Tachysphex  panzeri  selects  grasshoppers  of  the  family 
Acridiidae.  Larra  pompiliformis  (  =  Tachytes  nigcr,  Fabre)  some- 
times associates  itself  with  Sphex  flavipennis  (?  S.  maxillosus, 
according  to  Kohl),  forming  its  burrow  amidst  the  works  of  a 
colony  of  that  species,  and  making  use,  like  the  Sphex,  of  crickets 
for  provender.  This  led  Fabre  to  believe  that  the  Larra  stole 
its  prey  from  the  Spliex,  but  he  has  since  withdrawn  this  indict- 
ment, and  declares  that  the  Larra  obtains  its  crickets  by  the  more 
honourable,  if  not  more  humane,  process  of  catching  and  stinging 
them  itself.  Smith  has  informed  us,  on  the  faith  of  his  own 
observation,  that  L.  pompiliformis  uses  both  Lepidopterous  larvae 
and  grasshoppers  for  its  stores. 

T.  (Larrada)  australis,  according  to  Whittell,  plays  the  part  of 
a  burglar,  breaking  open  the  cells  of  Pelopaeus  (Sceliphrori)  laetus 
after  they  have  been  completed  and  stored  with  spiders ;  it  then 
takes  possession  of  the  cell,  and  curiously  enough  the  Pelopaeus 
permits  this,  although  the  cell  contains  its  egg  and  the  store 
of  food  that  is  intended  for  the  use  of  its  own  young.  To  us 
this  seems  very  strange,  but  it  is  probable  that  the  Pelopaeus 
has  no  idea  of  the  consecpuences  of  the  intruder's  operations  ; 


I  I  8  HYMENOPTERA 


CHAP. 


it  being  one  of  the  strange  facts  of  nature  that  these  highly 
endowed  creatures  never  even  see  the  offspring  for  whose  welfare 
they  labour  with  such  extraordinary  ingenuity  and  perseverance. 
Neither  can  we  suppose  that  they  have  a  conception  of  it 
derived  from  a  knowledge  of  their  own  individual  history ;  for 
their  very  complete  metamorphosis  is  scarcely  reconcilable  with 
any  such  recollection  on  their  part.  It  may  possibly  therefore 
be  the  case  that,  having  no  idea  whatever  of  the  offspring,  they 
are  equally  destitute  of  any  conception  that  it  will  lie  destroyed  by 
the  operations  of  the  Larrada.  However  this  may  be,  "Whittell 
informs  us  that  both  wasps  skirmish  about  for  a  little  as  if  each 
were  mistrustful  and  somewhat  afraid  of  the  other  ;  this  ends  by 
the  Pelopaeus  withdrawing  its  opposition  and  by  the  Larrada 
taking .  possession  of  the  cell,  which  it  then  proceeds  to  divide 
into  two,  using  for  the  purpose  of  the  partition  portions  of  the 
material  of  the  nest  itself;  possibly  it  is  only  a  contraction  of 
the  size  of  the  cell,  not  a  true  division,  that  is  effected  ;  however 
this  may  be,  after  it  is  accomplished  the  Larradn  deposits  its 
own  egg  in  the  cell,  having,  it  is  believed  by  "Whittell,  previously 
destroyed  that  of  the  Pelopaeus.  Judging  from  what  occurs  in 
other  species  it  is,  however,  more  probable  that  the  destruction 
of  the  egg  or  young  of  the  Pelopaeus  is  carried  out  by  the  larva 
of  the  Larrada  and  not  by  the  parent-wasp.  From  a  remark 
made  by  Maindron  as  to  the  proceedings  of  Larrada  nivde^in, 
in  Ternate,  it  seems  probable  that  its  habits  may  prove  to  be 
similar  to  those  of  L.  australis,  for  it  frequents  the  nests  of 
Pelopaeus  after  they  have  been  completed. 

Sub-Fam.  4.  Trypoxylonides. — Differ  from  Lan-ide*  by  the 
inner  margin  of  the  eyes  being  concave,  and  the  marginal 
cell  not  appendiculate.  (In  Trypoxylon  there  is  only  one 
distinct  submarginal  and'  one  distinct  discoidal  cell,  a  second 
of  each  being  indicated  faintly.} 

The  nervuration  of  Trypoxylon  is  very  peculiar,  and  differs 
from  that  of  the  widely-distributed  genus  Pison,  though  according 
to  Kohl's  views  the  two  may  be  correctly  associated  to  form 
this  sub-family.  The  species  of  Trypoxylon  ;m-  apparently  rather 
fond  of  human  propinquity,  and  build  clay-  or  mud-nests  in  or 
inMi'  houses.  T.  albitarse  has  this  habit,  and  is  well  known  in 
Southern  Brazil  under  the  name  of  "  Marimbouda  da  casa  " 


Ill 


SPHEGIDAE ASTATIDES BEMBECIDE 


119 


this  Insect,  like  Pelopaeus,  stores  its  nest  with  spiders,  and 
Peckholt  has  remarked  that  however  great  may  be  the  number  of 
spiders  placed  by  the  mother-wasp  in  a  cell,  they  are  all  consumed 
by  the  larva,  none  ever  being  found  in  the  cell  after  the  perfect 
Insect  escapes  therefrom.  The  European  T.  figulus  forms  a  nest 
either  in  bramble-stems  or  in  sandy  soil  or  walls  ;  it  makes  use 
of  spiders  as  provisions. 

Sub-Fam.  5.   Astatides.  —  Eyes  very  large  in  the  male,  meeting 
'broadly  on  the  vertex  ;   two  spurs  on  the  middle  tibia. 

We  have  two  species  of  the  genus  Astata  in  Britain  :  one  of 
them  —  A.  loops  —  is  known  to  form  burrows  in  the  ground,  each 
of  which  contains  only  a  single  cell  ;  this,  it  appears,  is  usually 
provisioned  with  bugs  of  the 
genus  Pentaloma,  Insects  re- 
markable for  their  strong  and 
offensive  odour.  St.  Fargeau 
records  that  this  species  also 
makes  use  of  a  small  cockroach 
for  forming  the  food  -  store  : 
thus  exhibiting  an  unique 
catholicity  in  the  toleration  of 
the  disagreeable  ;  almost  the 
only  point  of  connection  be- 
tween bus  and  cockroaches 


FlG'  46  —Astata 


male-    Britaln- 


being  their  disagreeable  char- 
acter. According  to  Smith,  Oxybelus,  another  genus  of  Fossores, 
is  also  used.  Authorities  are  far  from  agreement  as  to  the 
validity  and  relations  of  the  sub-family  Astatides.  It  consists 
only  of  the  widely-distributed  genus  Astata,  with  which  the 
North  American  Diploplectron  (with  one  species)  is  doubtfully 
associated. 

Sub  -  Fam.  6.  Bembecides.  -  -  Labrum  frequently  elongate  ; 
wing  -  nervures  extending  very  near  to  the  outer  margin; 
marginal  cell  of  front  wing  not  appendiculate ;  mandibles 
not  emarginale  externally  ;  kind  body  stout,  not  pedicellate. 

The   elongation  of  the   labruni,  though  one  of  the  most   trust- 
worthy of  the  characters  of  the  Bembecides,  cannot  be  altogether 


I2O 


HYMENOPTERA 


CHAP. 


relied  on  owing  to  the  variation  it  presents  both  in  this  and  the 
allied  sub-families.  The  Bembecides  carry  their  prey  to  their 
young  tucked  underneath  their  own  bodies  and  hugged  to  the 
breast ;  they  affect  loose,  sandy  soils  for  nidification  ;  make  use, 
in  the  great  majority  of  the  cases  where  the  habits  are  known, 
of  Diptera  for  provisions,  and  give  these  dead  to  the  young ; 
making  repeated  visits  to  supply  fresh  food  to  the  progeny,  which 
notwithstanding  this  fact,  are  distributed  in  isolated  burrows. 

One  of  the  most  interesting  of  Fabre's  studies  of  the  instincts 
of  Hymenoptera  is  devoted  to  Bembex  rostrata.  The  Bembecides 
have  the  habit  of  forming  their  nests  in  the  ground  in  wide 

expanses  of  sand,  and  of  cover- 
ing them  up,  they  leave  them 
so  that  there  appears  to  be 
absolutely  nothing  by  which 
the  exact  position  of  the  nest 
can  be  traced ;  nevertheless  the 
!:<•  in  hex  flies  direct  to  it  with- 
out any  hesitation.  How  neces- 
sary it  is  to  these  Insects  to 
possess  this  faculty  of  finding 
their  nests  will  be  understood 
when  we  recall  that  the  Bembex 


FIG.  47.  —  Bembex  rostrata 


Europe. 


does  not  provision  its  nest  once  and  for  all,  but  supplies  the  young 
at  first  with  only  insufficient  food,  and  has  therefore  to  return  at 
daily,  or  other  intervals,  with  a  fresh  store  of  provisions.  The  burrow 
is  made  in  the  sand  by  means  of  the  fore-legs ;  these  work  with 
such  rapidity  and  skill  that  a  constant  stream  of  sand  flows  out 
behind  the  Insect  while  it  is  engaged  in  the  act  of  excavation. 
The  nest  or  cell  in  which  the  larva  is  to  live,  is  formed  by  this 
process  of  digging ;  but  no  fastening  together  of  the  material 
occurs,  nor  does  any  expedient  seem  to  be  resorted  to,  other 
than  that  of  making  a  way  through  the  sand  by  clearing  out  all 
the  pieces  of  stick  or  stone  that  might  diminish  facility  of  access. 
The  cell  being  formed,  the  Bembex  leaves  the  spot  in  search  of 
prey,  and  when  it  has  secured  a  victim  in  the-  shape  of  a  two- 
winged  fly,  it  returns  therewith  to  the  burrow,  and  the  booty  is 
placed  therein,  an  egg  being  deposited  on  it.  The  wasp  then 
leaves  the  burrow,  disguising,  however,  the  spot  where  it  is 
situate,  and  Hies  away:  to  proceed  possibly  with  the  formation 


in  SPHEGIDAE BEMBECIDES  121 

of  other  burrows.1  In  the  course  of  twenty -four  hours  the 
egg  hatches,  and  the  larva  in  two  or  three  days  completely 
devours  the  stock  provided  for  it.  The  mother  -  wasp  then 
returns  with  another  fly — this  time  probably  a  larger  one- 
penetrates  rapidly  to  the  bottom  of  the  burrow,  and  again  re- 
treats, leaving  the  second  stock  of  provisions  for  the  benefit  of 
the  greedy  larva.  These  visits  of  supply  are  repeated  with  increased 
frequency,  as  the  appetite  of  the  larva  for  the  benefit  of  which 
they  are  made  increases  with  its  growth.  During  the  fourteen 
or  fifteen  days  that  form  this  portion  of  the  life-cycle,  the  single 
larva  is  supplied  with  no  less  than  fifty  to  eighty  flies  for  food. 
To  furnish  this  quantum,  numerous  visits  are  made  to  each 
burrow,  and  as  the  mother  Benibex  has  several  burrows — though 
how  many  does  not  appear  to  be  known — her  industry  at  this 
time  must  be  very  great.  All  the  while,  too,  a  great  danger  has 
to  lie  avoided,  for  there  is  an  enemy  that  sees  in  the  booty 
brought  by  the  Bembex  to  its  young,  a  rich  store  for  its  own 
progeny.  This  enemy  is  a  feeble,  two-winged  fly  of  the  family 
Tachinidae  and  the  genus  Miltogramma ;  it  hangs  about  the 
neighbourhood  of  the  nests,  and  sooner  or  later  finds  its 
opportunity  of  descending  on  the  prey  the  Bembex  is  carrying, 
choosing  for  its  purpose  a  moment  when  the  Bcmlex  makes  a 
brief  delay  just  at  the  mouth  of  the  burrow ;  then  down  comes 
the  Miltogramma,  and  lays  one,  two,  or  three  eggs  on  some  portion 
of  the  booty  that  may  be  projecting  from  beneath  the  body  of 
the  wasp.  This  latter  carries  in  the  food  for  its  own  young,  but 
thus  introduces  to  the  latter  the  source  of  its  destruction,  for  the 
Miltogramma  larvae  eat  up  the  supply  of  food  intended  for  the 
Bembex  larvae,  and  if  there  be  not  enough  of  this  provender  they 
satisfy  their  voracity  by  eating  the  Bembex  larva  itself.  It  is  a 
remarkable  fact  that  notwithstanding  the  presence  of  these 
strange  larvae  in  the  nest  the  mother  Bembex  continues  to  bring 
food  at  proper  intervals,  and,  what  is  stranger  still,  makes  no 
effort  to  rid  the  nest  of  the  intruders  :  returning  to  the  burrow 
with  a  supply  of  food  she  finds  therein  not  only  her  legitimate 
offspring,  a  single  tenant,  but  several  others,  strangers,  it  may 
be  to  the  number  of  twelve ;  although  she  would  have  no 
difficulty  in  freeing  the  nest  from  this  band  of  little  brigands, 
she  makes  no  attempt  to  do  so,  but  continues  to  bring  the 

1  See  on  this  point  the  note  on  p.  130. 


122  HVMENOPTERA  CHAP. 

supplies.  In  doing  so  she  is  fulfilling  her  duty ;  what  matters 
it  that  she  is  nourishing  the  enemies  of  her  race  ?  Both  race 
and  enemies  have  existed  for  long,  perhaps  for  untold  periods  of 
time,  why  then  should  she  disturb  herself,  or  deviate  from  her 
accustomed  range  of  duties  ?  Some  of  us  will  see  in  such  pro- 
ceedings only  gross  stupidity,  while  •  others  may  look  on  them  as 
sublime  toleration. 

The  peculiar  habits  of  Bmibex  rostrata  are  evidently  closely 
connected  with  the  fact  that  it  actually  kills,  instead  of  merely 
paralysing,  its  prey  ;  hence  the  frequent  visits  of  supply  are  neces- 
sary that  the  larvae  may  have  fresh,  not  putrefying,  food ;  it  may 
also  be  because  of  this  that  the  burrow  is  made  in  a  place  of  loose 
sand,  so  that  rapid  ingress  may  be  possible  to  the  Bembex  itself, 
while  the  contents  of  the  burrow  are  at  the  same  time  protected 
from  the  inroads  of  other  creatures  by  the  burrow  being  filled 
up  with  the  light  sand.  Fabre  informs  us  that  the  Bemlex 
larva  constructs  a  very  remarkable  cocoon  in  connection  with 
the  peculiar  nature  of  the  soil.  The  unprotected  creature  has 
to  pass  a  long  period  in  its  cocoon,  and  the  sandy,  shifting  soil 
renders  it  necessary  that  the  protecting  case  shall  be  solid  and 
capable  of  keeping  its  contents  dry  and  sound.  The  larva,  how- 
ever, appears  to  have  but  a  scanty  supply  of  silk  available  for 
the  purpose  of  constructing  the  cocoon,  and  therefore  adopts  the 
device  of  selecting  grains  of  sand,  and  using  the  silk  as  a  sort  of 
cement  to  connect  them  together.  For  a  full  account  of  the 
ingenious  way  in  which  this  difficult  task  is  accomplished  the 
reader  should  refer  to  the  pages  of  Fabre  himself.  Bembe- 
cides  appear  to  be  specially  fond  of  members  of  the  Tabanidae 
(or  Gad-fly  family)  as  provender  for  their  young.  These1  flies 
infest  mammals  for  the  purpose  of  feasting  on  the  blood  they 
can  draw  by  their  bites,  and  the  Bembecides  do  not  hesitate  to 
capture  them  while  engaged  in  gratifying  their  blood-thirsty  pro- 
pensities. In  North  America  a  large  species  of  Bembecid  some- 
times accompanies  horsemen,  and  catches  the  flies  that  come  to 
attack  the  horses ;  and  Bates  relates  that  on  the  Amazons  a 
Bembecid  as  large  as  a  hornet  swooped  down  and  captured  one 
of  the  large  blood-sucking  Motuca  flies  that  had  settled  on  his 
neck.  This  naturalist  has  given  an  account  of  some  of  the 
Bembecides  of  the  Amazons  Valley,  showing  that  the  habits  there 
are  similar  to  those  of  their  European  congeners. 


in  SPHEGIDAE NYSSONIDES  123 

Sphecius  speciosus  is  a  member  of  the  Stizinae,  a  group  recog- 
nised by  some  as  a  distinct  sub-family.  It  makes  use,  in  North 
America,  of  Insects  of  the  genus  Cicada  as  food  for  its  young. 
Burrows  in  the  ground  are  made  by  the  parent  Insect ;  the  egg- 
is  deposited  on  the  Cicada,  and  the  duration  of  the  feeding-time 
of  the  larva  is  believed  to  be  not  more  than  a  week  ;  the  pupa 
is  contained  in  a  silken  cocoon,  with  which  much  earth  is  incor- 
porated. Eiley  states  that  dry  earth  is  essential  to  the  well- 
being  of  this  Insect,  as  the  Cicada  become  mouldy  if  the  earth 
is  at  all  damp.  As  the  Cicada  is  about  twice  as  heavy  as  the 
Sphecius  itself,  this  latter,  when  about  to  take  the  captured 
burden  to  the  nest,  adopts  the  plan  of  climbing  with  it  to  the 
top  of  a  tree,  or  some  similar  point  of  vantage,  so  that  during  its 
flight  it  has  to  descend  with  its  heavy  burden  instead  of  having 
to  rise  with  it,  as  would  be  necessary  if  the  start  were  made  from 
the  ground. 

Sub-Fam.  7.  Nyssonides. — Lcibrum  short;  mandibles  entire  on 
the  outer  edge;  hind  liody  usually  not  pedicellate;  wing 
with  the  marginal  cell  not  appendicidate. 

This  group  has  been  but  little  studied,  and  there  is  not  much 
knowledge  as  to  the  habits  of  the  species.  It  is  admitted  to  be 
impossible  to  define  it  accurately.  It  is  by  some  entomologists 
considered  to  include  MeUinus,  in  which  the  abdomen  is  pedi- 
cellate (Fig.  48),  while  others  treat  that  genus  as  forming  a 
distinct  sub-family,  Mellinides.  Kohl  leaves  MeUinus  unclassified. 
Gerstaecker  has  called  attention  to  the  fact  that  many  of  the 
Insects  in  this  group  have  the  trochanters  of  the  hind  and  middle 
legs  divided :  the  division  is,  as  a  rule,  not  so  complete  as  it 
usually  is  in  Hymenoptera  Parasitica  ;  but  it  is  even  more  marked 
in  some  of  these  Nyssonides  than  it  is  in  certain  of  the  parasitic 
groups. 

MeUinus  arvensis  is  one  of  our  commonest  British  Fossores, 
and  we  are  indebted  to  the  late  F.  Smith  for  the  following 
account  of  its  habits  :  "  It  preys  upon  flies,  and  may  be  commonly 
observed  resorting  to  the  droppings  of  cows  in  search  of  its  prey; 
it  is  one  of  the  most  wary  and  talented  of  all  its  fraternity ;  were 
it  at  once  to  attempt,  by  a  sudden  leap,  to  dart  upon  its  victim, 
ten  to  one  it  would  fail  to  secure  it ;  no,  it  does  no  such  thing, 
it  wanders  about  in  a  sort  of  innocent,  unconcerned  way,  amongst 


124  HYMENOPTERA  CHAP. 

the   deluded   flies,  until   a  safe   opportunity  presents   itself,  when 

its  prey  is  taken  without  any 
chance  of  failure  ;  such  is  its 
ordinary  mode  of  proceeding.  At 
Bournemouth  the  flies  are  more 
active,  more  difficult  to  capture, 
or  have  they  unmasked  the 
treacherous  Mellinus  ?  and  is  it 
found  necessary  to  adopt  some 
fresh  contrivance  in  order  to 
*  accomplish  its  ends  (  if  so,  it  is 

FIG.  48. — Mellinus  arcensis  ?.     Britain.  i    .c    •  i  T 

not     deficient     in     devices. 

noticed  once  or  twice,  what  I  took  to  he  a  dead  specimen  of 
Mellinus,  lying  on  patches  of  cow-dung ;  but  on  attempting 
to  pick  them  up  off  they  flew ;  I  at  once  suspected  the  crea- 
ture, and  had  not  long  to  wait  before  my  suspicions  were 
confirmed.  Another,  apparently  dead  fellow,  was  observed ;  and 
there,  neither  moving  head  or  foot,  the  treacherous  creature  lay, 
until  a  fine  specimen  of  a  Bluebottle  ventured  within  its  grasp, 
when,  active  as  any  puss,  the  Mellinus  started  into  life,  and 
pounced  upon  its  victim." 

Lucas  states  that  in  the  north  of  Prance  Mellinus  salnilosus 
provisions  its  nest  with  Diptera,  which  it  searches  for  on  the 
flowers  of  Umbelliferae,  and  then  carries  to  its  nest.  This  is  a 
burrow  in  the  earth,  and  when  it  is  reached  the  Hymeuopteron 
deposits  its  Insect  burden  for  a  moment  on  the  ground  while  it 
turns  round  in  order  to  enter  the  burrow  backwards.  The  same 
writer  states  that  two  varieties  of  this  Insect  live  together — or 
rather  in  the  same  colonies — and  make  use  of  different  species 
of  Diptera,  even  of  different  genera,  as  food  for  their  young. 
These  Diptera  are  stung  before  being  placed  in  the  nest.  The 
stinging  does  not  kill  the  Insect,  however,  for  Lucas  was  able  to 
keep  one  specimen  alive  for  six  weeks  after  it  had  passed  this 
trying  ordeal. 

Sub-Fam.  8.  Philanthides. — Laltnun  small  ;  anterior  icings  ivith 
three  complete,  submarginal  o  /As ;  him  I  l>»t///  constricted  at 
the  base  Imt  not  so  as  to  form  a  slender  pedicel. 

This   sub-family   contains   Insects   resembling   wasps  or    Tra- 
limnides  in  appearance,  and  is,  as  regards  the  pronotal  structure, 


Ill 


SPHEGIDAE-  -PHILANTHIDES 


125 


intermediate  between  the  two  great  divisions  of  the  Fossores,  for 
the  pronotal  lobe  extends  nearly  or  quite  as  far  back  as  the 
tegulae,  and  in  Philanthus  the  two  come  into  almost  actual 
contiguity. 

The  species  of  the  genus  Cerceris  are  numerous  in  Europe, 
and  several  of  them  are  known  to  make  burrows  in  the  ground, 
and  store  them  with  beetles  for  the  benefit  of  the  future  larvae. 
The  beetles  chosen  differ  in  family  according  to  the  species  of 
Cerceris  ;  but  it  appears  from  the  observations  of  Fabre  and  Dufour 
that  one  kind  of  Cerceris 
never  in  its  selection  goes 
out  of  the  limits  of  a 
particular  family  of 
beetles,  but,  curiously 
enough,  will  take  Insects 
most  dissimilar  in  form 
and  colour  provided  they 
belong  to  the  proper 
family.  This  choice,  so 
wide  in  one  direction  and 
so  limited  in  another, 
seems  to  point  to  the 
existence  of  some  sense, 


FIG.  49. — Philanthus  triaiiyulttm  6-     Britain. 


of  the  nature  of  which  we  are  unaware,  that  determines  the 
selection  made  by  the  Insect.  In  the  case  of  our  British  species 
of  Cerceris,  Smith  observed  C.  arenaria  carrying  to  its  nest  Cur- 
culionidae  of  very  diverse  forms ;  while  C.  labiata  used  a  beetle 
—Haltica  tabida — of  the  family  Chrysomelidae. 

The  beetles,  after  being  caught,  are  stung  in  the  chief 
articulation  of  the  body,  that,  namely,  between  the  pro-  and 
mesothorax.  Cerceris  lupresticida  confines  itself  exclusively  to 
beetles  of  the  family  Buprestidae.  It  was  by  observations  on 
this  Insect  that  Dufour  first  discovered  the  fact  that  the  Insects 
stored  up  do  not  decay  :  he  thought,  however,  that  this  was  due 
to  the  liquid  injected  by  the  wasp  exercising  some  antiseptic 
power;  but  the  observations  of  Fabre  have  shown  that  the  pre- 
servation in  a  fresh  state  is  due  to  life  not  being  extinguished  ; 
the  stillness,  almost  as  if  of  death,  being  due  to  the  destruction 
of  the  functional  activity  of  the  nerve  centres  that  govern  the 
movements  of  the  limbs. 


126  IIYMENOPTERA 


CHAP. 


It  has  long  been  known  that  some  species  of  Cerceris  prey  on 
bees  of  the  genus  Hal  ictus,  and  Marchal  has  recently  described 
in  detail  the  proceedings  of  C.  ornata.  This  Insect  catches  'a 
Halictus  on  the  wing,  and,  holding  its  neck  with  the  mandibles, 
bends  her  body  beneath  it,  and  paralyses  it  by  a  sting  admin- 
istered at  the  front  articulation  of  the  neck.  The  Halictus  is 
subsequently  more  completely  stunned  or  bruised  by  a  process  of 
kneading  by  means  of  the  mandibles  of  the  Cerceris.  Marchal 
attaches  great  importance  to  this  "  malaxation  "  ;  indeed,  he  is  of 
opinion  that  it  takes  as  great  a  part  in  producing  or  prolonging 
the  paralysis  as  the  stinging  does.  Whether  the  malaxation 
would  be  sufficient  of  itself  to  produce  the  paralysis  he  could  not 
decide,  for  it  appears  to  be  impossible  to  induce  the  Cerceris  to 
undertake  the  kneading  until  after  it  has  reduced  the  Halictus 
to  quietude  by  stinging. 

Fabre  made  some  very  interesting  observations  on  Cerceris 
tnlerculiita,  their  object  being  to  obtain  some  definite  facts  as  to 
the  power  of  these  Insects  to  find  their  way  home  when  removed 
to  a  distance.  He  captured  twelve  examples  of  the  female, 
marked  each  individual  on  the  thorax  with  a  spot  of  white 
paint,  placed  it  in  a  paper  roll,  and  then  put  all  the  rolls,  with 
their  prisoners,  in  a  box  ;  in  this  they  were  removed  to  a  distance 
of  two  kilometres  from  the  home  and  then  released.  He  visited 
the  home  five  hours  afterwards,  and  was  speedily  able  to  assure 
himself  that  at  any  rate  four  out  of  the  twelve  had  returned  to 
the  spot  from  whence  they  had  been  transported,  and  he  enter- 
tained no  doubt  that  others  he  did  not  wait  to  capture  had  been 
equally  successful  in  home- finding.  He  then  commenced  a  second 
experiment  by  capturing  nine  examples,  marking  each  with  two 
spots  on  the  thorax,  and  confining  them  in  a  dark  box.  They 
were  then  transported  to  the  town  of  Carpentras,  a  distance  of 
three  kilometres,  and  released  in  the  public  street,  "  in  the  centre 
of  a  populous  quarter,"  from  their  dark  prison.  Each  Cerceris 
on  being  released  rose  vertically  between  the  houses  to  a  sufficient 
height,  and  then  at  once  passed  over  the  roofs  in  a  southerly 
direction— the  direction  of  home.  After  some  hours  he  went 
back  to  the  homes  of  the  little  wasps,  but  could  not  find  that 
any  of  them  hail  then  returned;  the  next  day  he  went  again, 
and  found  that  at  any  rate  five  of  the  Cerceris  liberated  the 
previous  day  were  then  at  home.  This  record  is  of  considerable 


in  SPHEGIDAE — MIMESIDES  I2/ 

interest  owing  to  two  facts,  viz.  that  it  is  not  considered  that  the 
Cerceris  as  a  rule  extends  its  range  far  from  home,  and  that  the 
specimens  were  liberated  in  a  public  street,  and  took  the  direc- 
tion of  home  at  once. 

Philanthus  apivorus  is  one  of  the  best  known  of  the  members 
of  this  sub -family  owing  to  its  habit  of  using  the  domestic 
honey-bee  as  'the  food  for  its  offspring.  In  many  respects  its 
habits  resemble  those  of  Cerceris  ornata,  except  that  the  Pkil- 
anthus  apparently  kills  the  bee  at  once,  while  in  the  case  of  the 
Cerceris,  the' Hal-ictus  it  entombs  does  not  perish  for  several  days. 
The  honey-bee,  when  attacked  by  the  Philanthus,  seems  to  be 
almost  incapable  of  defending  itself,  for  it  appears  to  have  no 
power  of  finding  with  its  sting  the  weak  places  in  the  armour, 
of  its  assailant.  According  to  Fabre,  it  has  no  idea  of  the  Phil- 
anthus "being  the  enemy  of  its  race,  and  associates  with  its 
destroyer  on  amicable  terms  previous  to  the  attack  being  made  on 
it.  The  Philanthus  stings  the  bee  on  the  under- surface  of  the 
mentum  ;  afterwards  the  poor  bee  is  subjected  to  a  violent  process 
of  kneading,  by  which  the  honey  is  forced  from  it,  and  this  the 
destroyer  greedily  imbibes.  The  bee  is  then  carried  to  the  nest 
of  the  Philanthus.  This  is  a  burrow  in  the  ground  ;  it  is  of 
unusual  depth — about  a  yard  according  to  Fabre — and  at  its  ter- 
mination are  placed  the  cells  for  the  reception  of  the  young  ;  in 
one  of  these  cells  the  bee  is  placed,  and  an  egg  laid  on  it :  as 
the  food  iu  this  case  is  really  dead,  not  merely  in  a  state  of 
anaesthesia,  the  Pkilanthus  does  not  complete  the  store  of  food 
for  its  larvae  all  at  once,  but  waits  until  the  latter  has  consumed 
its  first  stock,  and  then  the  mother-wasp  supplies  a  fresh  store 
of  food.  In  this  case,  therefore,  as  in  Bembex,  the  mother  really 
tends  the  offspring. 

Sub-Fam.  9.  Mimesides.  -  -  Small  Insects  with  pedicellate  hind 
body,  tlie  pedicel  not  cylindric ;  mandibles  not  excised  ex- 
ternally ;  inner  margin  of  eyes  not  concave ;  middle  tibia 
with  one  spur ;  wings  with  two,  or  three,  submarginal  cells. 

Mimesides  is  here  considered  to  include  the  Pemphredonides 
of  some  authors.  Mimesides  proper  comprises  but  few  forms,  and 
those  known  are  small  Insects.  Psen  concolor  and  P.  a.tratus 
form  their  nests  in  hollow  stems,  and  the  former  provisions  its 
nest  with  Homopterous  Insects  of  the  family  Psyllidae.  Little 


128 


HYMENOPTERA 


CHAP. 


FIG.  50. — Mimesa  bicolor  f, 
Britain. 


information  exists  as  to  their  liabits  ;   but   Verhoeff  states   that 

the  species  of  Pscn  —  like  mem- 
bers of  the  Pemphredoninae— 
do  not  form  cocoons. 

The  Pemphredonine  subdivi- 
sion includes  numerous  small  and 
obscure  Insects  found  chiefly  in 
Europe  and  North  America  (Fig. 
51,  P.  lugubris)',  they  resemble 
the  smaller  black  species  of  Cra- 
bronides,  and  are  distinguished 
from  them  chiefly  by  the  exist- 
ence of  at  least  two  complete, 
submarginal  cells  on  the  an- 
terior wing  instead  of  one. 
The  species  of  Passaloecus  live  in  the  burrows  that  they  form 

in  the  stems  of  plants  ;  Pemphredon  lugubris  frequents  the  decayed 

wood  of  the  beech.      The  larva  and  pupa  of  the  latter  have  been 

described    by    Verhoeff;   no 

cocoon    is    formed    for    the 

metamorphosis.     Both  these 

genera  provision  their  nests 

with     Aphidae.        This 

also  the  case  with  Stt 

pendulus,  but    the    burrows 

of  this  species  form  a  com- 

plex  system    of  diverticula 

proceeding  from  an   irregu- 

lar main  channel  formed  in 

the  pithy  stems   of  bushes. 

Cemonus    unicolor,  according   to    Giraud,    forms    its    burrows    in 

bramble  -  stems,   but   it   also    takes   advantage,  for    the  purposes 

of  nidification,  of   the  abandoned    galls   of   Ct/nij>n,   and   also   ol 

a    peculiar   swelling    formed   by   a    fly  —  Llpm-n   lucens    —on    the 

common    reed,    Arundo    p/i  /•</>/  mites.      This    species    also    makes 

use  of  Aphidae,  and  Verhoeff  states  that  it  has  only  an  imperfect 

instinct  as  to  the  amount  of  iood  it  stores. 

Sub-Fam.  10.   Crabronides  --Pi'onoitun  short,  front  u-rmj  u-iih 
one  co////>/i  fr  submarginal  and  two  discoidal  cell*  :   hind  body 


s 


FIG.  51. — Pemphredon  luyitbris  9.     Britain. 


Ill 


SPHEGIDAE CRABRONIDES 


129 


/•(triable  in  form,  pedicellate  in  some  abnormal  forms,  but  more 
usually  not  stalked. 

The  Crabronides  ( Vespa  crabro,  the  hornet,  is  not  of  this  sub- 
family) are  wasp-like  little  Insects,  with  unusually  robust  and 
quadrangular  head.  They  frequently  have  the  hind  tibiae  more 
or  less  thickened,  and  the  clypeus  covered  with  metallic  hair. 
It  appears  at  present 
that  they  are  specially 
attached  to  the  tem- 
perate regions  of  the 
northern  hemisphere, 
but  this  may  possibly  be 
in  part  due  to  their 
having  escaped  attention 
elsewhere.  In  Britain 
they  form  the  most  im- 
portant part  of  the 
fossorial  Hymenoptera, 
the  genus  Crabro 
(with  numerous  sub- 
genera)  itself  comprising  thirty  species.  The  males  of  some  of 
the  forms  have  the  front  tibiae  and  tarsi  of  most  extraordinary 
shapes.  They  form  burrows  in  dead  wood,  or  in  pithy  stems, 
(occasionally  in  the  earth  of  cliffs),  and  usually  store  them  with 
Diptera  as  food  for  the  larvae :  the  wings  and  dried  portions  of 
the  bodies  of  the  flies  consumed  by  Crabronides  are  often  exposed 
to  view  when  portions  of  old  wood  are  broken  from  trees. 

The  genus  Oxybelus  is  included  by  some  systematists,  but 
with  doubt,  in  this  sub-family  ;  if  not  placed  here,  it  must  form  a 
distinct  sub-family.  It  has  the  metathorax  spinose,  and  the  sub- 
marginal  and  first  discoidal  cells  are  not,  or  are  scarcely,  separated. 

Crabro  leucostomus  has  been  observed  by  Fletcher  to  form 
cells  for  its  larvae  in  the  soft  wood  of  broken  willows  :  the  food 
stored  therein  consists  of  two-winged  flies  of  the  family  Dolicho- 
podidae.  This  Crabro  is  parasitised  by  an  Ichneumonid  of  the 
genus  Tryphon,  and  by  a  two-winged  fly  of  uncertain  genus,  but 
belonging  to  the  family  Tachinidae.  The  metamorphoses  of 
Crabro  clirysostomus  have  been  briefly  described  by  Verhoeff: 
the  food  stored  consists  of  Diptera,  usually  of  the  family  Syr- 

VOL.  VI  K 


FIG.  52. — Crabro  cephalotes  ? .     Britain. 


130  HYMENOPTERA  CHAP,  in 

phidae  ;  the  larva  spins  an  orange-red  cocoon,  passes  the  winter 
therein,  and  assumes  the  pupal  form  in  the  spring ;  there  is,  he 
says,  a  segment  more  in  the  female  pupa  than  there  is  in  the  male. 

The  species  of  the  sub-genus  Crossocerus  provision  their  nests 
with  Aphididae,  but  C.  wesmaeli  makes  use,  for  the  purpose, 
according  to  Ferton,  of  an  elegant  little  fly  of  the  family 
Tipulidae ;  according  to  Pissot  this  same  wasp  also  makes  use 
of  a  species  of  Typldocylta,  a  genus  of  the  Homopterous  division  of 
Rhynchota.  Supposing  there  to  be  no  mistake  as  to  this  latter 
observation,  the  choice  of  Diptera  and  of  Homoptera  by  the  same 
species  indicates  a  very  peculiar  habit. 

Fertonius  (Crossocerus}  luteicollis  in  Algeria  forms  cells  at  a 
slight  depth  in  sandy  soil,  and  provisions  them  with  ants.  The 
ant  selected  is  Tapinoma  erraticum,  and  the  individuals  captured 
are  the  wingless  workers.  The  mode  of  hunting  has  been  de- 
scribed by  Ferton  ;  the  \vasp  hovers  over  one  of  the  ant-paths  at  a 
distance  of  a  few  millimetres  only  above  the  surface,  and  when 
an  ant  that  is  considered  suitable  passes,  the  Fertonius  pounces 
on  it,  stings  it,  and  carries  it  off  to  the  burrow  ;  forty  or  fifty 
ants  are  accumulated  in  a  cell,  the  egg  is  laid  in  the  heap  of 
victims  about  one-third  of  the  depth  from  the  bottom;  the 
resulting  larva  sucks  the  ants  one  by  one,  by  attaching  itself  to 
the  thorax  behind  the  first  pair  of  legs.  There  is  a  very 
interesting  point  in  connection  with  the  habits  of  this  species, 
viz.  that  the  ants  are  not  only  alive,  but  lively ;  they  have, 
however,  lost  the  power  of  co-ordinating  the  movements  of  the 
limbs,  and  are  thus  unable  to  direct  any  attack  against  the  feeble 
larva.  Ferton  thinks  there  are  three  generations  of  this  species 
in  a  single  year. 

NOTE. — In  a  note  on  p.  99  we  have  mentioned  the  new  publication  of 
Mr.  and  Mrs.  Peckham  on  the  habits  of  Fossores.  We  may  here  add  that  it 
contains  much  fresh  information  on  these  Insects,  together  with  criticisms  of 
the  views  of  Fabre  and  others.  One  of  the  points  most  noteworthy  is  that 
they  have  observed  Crabro  stirpicola  working  night  and  day  for  a  period  of 
forty-two  consecutive  hours.  They  made  experiments  on  Sembex  spinolae 
with  a  view  of  ascertaining  whether  the  female  provisions  two  nests  simul- 
taneously ;  as  tlie  result  they  think  this  improbable.  If  the  female  Beinbeeid 
make  nests  only  consecutively,  it  is  clear  it  must  have  but  a  small  fecundity. 
The  larval  life  extends  over  about  fifteen  days  ;  and  if  we  allow  three  months 
as  the  duration  of  life  of  a  female,  it  is  evident  that  only  about  six  young 
can  be  produced  in  a  season. 


CHAPTER   IV 


HYMENOPTERA    ACULEATA    COXTIXUED- 

OR    ANTS 


-DIVISION  IV.    FORMICIDAE 


B 


Division  IV.  Heterogyna  or  Formicidae— Ants. 

The  segment,  or  the  two  segments,  behind  the  propodeum,  either 
small  or  of  irregular  form,  so  that  if  not  throughout  of 
small  diameter,  the  articulation  until  the  segment  behind  is 
slender,  and  there  is  great  mobility. 
The  trochanters  undivided.  The 
individuals  of  each  species  are 
usually  of  three  kinds,  males,  females 
and  workers ;  the  latter  h  are  no 
wings,  but  the  males  and  females 
(ire  usually  winged,  though  the 
females  soon  lose  the  flying  organs. 
They  live  in  communities  of  various 
numbers,  the  majority  being  workers. 
The  larvae  are  helpless  maggots  fed 
<f  nd  tended  by  the  ivorkers  or  by 

"  FIG.   53  — Abdomens    of   ants. 

A,   Of  Camponotus  ruli-i/^.-i 

IN    ants    the    distinction    between     the        (Formicides) ;  B,   of  Ecta- 

,-,  .  ^,111-  tnmma  auralum  (Ponerides); 

three  great  regions  of  the  body  is  very        c>  of  Aphmnog^i.,    bar- 
marked.       The    abdomen     is    connected        bara  (Myrmicides).    «,  Pro- 

.  .  podeum  ;  b,  first  abdominal 

with  the  propodeum  in  a  peculiar  manner,        segment  forming  a  scale  or 
one    or    two    segments    being    detached        node :  c,  second  ;  rf,  third 

abdominal  segment. 

from    the    main    mass    to    form    a    very 

mobile  articulation.      This  is  the  most  distinctive  of  the  char- 
acters of  ants.      The   structure  and  form  of  these  parts  varies 


132  HYMENOPTERA  CHAP. 

greatly  in  the  family  :  and  the  Amblyoponides  do  not  differ  in 
a  marked  manner  from  the  Scoliidae  in  ibssorial  Hymenoptera. 

The  arrangement  of  the  parts  of  the  mouth  is  remarkable, 
and  results  in  leaving  the  mandibles  quite  .free  and  unconnected 
with  the  other  trophi ;  the  mouth  itself  is,  except  during  feeding, 

closed  completely 
by  the  lower  lip 
and  maxilla  assum- 
ing an  ascending 
vertical  direction, 
while  the  upper 

FIG.  54.-Front  of  head  of  Dinopon  y  h  d 

A,  Mouth  closed  ;  B,  opi-n. 

and  overlaps  the 

lower  lip,  being  closely  applied  to  it ;  so  that1  in  Ponerides 
the  palpi,  except  the  apices  of  the  maxillary  pair,  are  enclosed 
between  the  upper  and  lower  lips  (Fig.  54,  A).  In  Cryptocerini 
the  palpi  are  not  covered  by  the  closed  lips,  but  are  protected  by 
being  placed  in  chinks  at  the  outsides  of  the  parts  closing  the 
mouth.  The  mandibles  of  ants  can  thus  be  used  in  the  freest 
manner  without  the  other  parts  of  the  mouth  being  opened  or  even 
moved.  The  mandibles  close  transversely  over  the  rest  of  the 
mouth,  and  when  shut  are  very  firmly  locked.  There  are, 
however,  some  ants  in  which  the  lips  remain  in  the  position 
usual  in  mandibulate  Insects. 

The  antennae,  except  in  the  males  of  some  species,  have  a 
long  basal  joint  and  are  abruptly  elbowed  at  its  extremity.  The 
eyes  and  ocelli  vary  excessively,  and  may  be  totally  absent  or 
very  highly  developed  in  the  same  species.  The  winged  forms 
are,  however,  never  blind.  The  size  of  the  head  varies  extremely 
in  the  same  species ;  it  is  frequently  very  small  in  the  males, 
and  largest  in  the  workers.  In  some  ants  the  worker-caste 
consists  of  large-headed  and  small- headed  individuals  ;  the  former 
are  called  soldiers,  and  it  has  been  supposed  that  some  of  them 
may  act  the  part  of  superior  officers  to  the  others.  It  should  be 
clearly  understood  that  there  is  no  definite  distinction  between 
soldiers  and  workers;  so  that  in  this  respect  they  are  widely 
different  from  Termites. 

The  complex  mass  forming  the  thorax  is  subject  to  great 
change  of  structure  in  the  same  species,  according  as  the  indi- 
viduals are  xvinged  or  wingless.  The  sutures  between  the  dorsal 


FORMICIDAE — ANTS 


133 


(notal)  pieces  are  frequently  obliterated  in  the  workers,  while 
they  are  distinct  in  the  males  and  females,  and  the  pieces  them- 
selves are  also  much  larger  in  size  in  these  sexed  individuals. 
The  pro-mesothoracic  stigma  is 
apparently  always  distinct ;  the 
meso-metathoracic  one  is  distinct 
in  the  male  Dorylus,  but  can  scarcely 
be  detected  in  the  winged  forms  of 
other  ants,  owing  to  its  being  en- 
closed within,  and  covered  by,  the 
suture  between  the  two  segments : 
in  the  workers,  however,  it  is  usually 
quite  conspicuous.  The  posterior 
part  of  the  thoracic  mass,  the  pro- 
podeum  or  median  segment,  is  of 
considerable  size  ;  no  transverse 
suture  between  the  component  pieces 
of  this  part  can  be  seen,  but  its 
stigma  is  always  very  distinct.  The  Fia  ^_0ecodoma  cephaMes.  South 

peduncle,  Or  pedicel,  formed    by    the  America.     A,   Worker   major  ;   B, 

,  .,  female  after  casting  the  wings. 

extremely   mobile    segment   or    seg- 
ments   at    the    base   of   the  abdomen   (already  noticed  as    form- 
ing the  most  conspicuous  character  of  the  family),  exhibits  much 


FIG.  56. — Stridulating  organ  of  an  ant,  Myrmica  rubra,  var.  laevinodis.  Sagittal  section 
of  part  of  the  6th  and  7th  post-cephalic  segments.  (After  Janet.)  a,  a1,  muscles  ; 
6,  connecting  membrane  (corrugated)  between  6th  and  7th  segments  :  c,  6th  seg- 
ment ;  d,  its  edge  or  scraper  ;  e,  striate  area,  or  file  on  7th  segment ;  /,  posterior 
part  of  7th  segment ;  g,  cells,  inside  body  ;  ,h,  trachea. 

variety.       Sometimes   the  first   segment  bears  a  plate  or  shield 
called   a   scale  (Fig.    53,   A,  V) ;    at    other    times    there    are    two 


134 


HYMENOPTERA 


CHAP. 


small  segments  (Fig.  53,  B,  C,  l>,  c~)  forming   nodes    or   knots,   of 

almost  any  shape.      The  articulations  between  these  segments  are 

of  the  most  perfect  description.      In  many  ants  these  parts  bear 

4 highly  developed  stridulating  organs, and  the  delicacy  and  perfection 

of  the  articulations  allow  the  parts  to  be 
moved  either  with  or  without  producing 
stridulation.  In  the  male  sex  the  peduncle 
and  its  nodes  are  much  less  perfect,  and 
possess  comparatively  little  capacity  for 
movement ;  in  the  male  of  Dorylus  (Figs. 
79,  A,  and  80,  /)  the  single  node  is 
only  imperfectly  formed.  The  eyes  and 
ocelli  of  the  males  are  usually  more 
largely  developed  than  they  are  in  the 
female,  though  the  head  is  much  smaller. 
The  legs  of  ants  are  elongate,  except 
in  a  few  forms ;  the  Cryptocerini  and 
the  males  of  Dorylides  being  the  most 
conspicuous  exceptions.  The  tarsi  are 
five -jointed,  the  basal  joint  being  dis- 
proportionately elongate,  so  that  in  use 
Fro.  57. — Combs  and  brushes  :  .•  .  •  /•  •, 

on  front  leg  of  an  ant,  Dino-  ^   acts  in   many  species  as  it   it  were  a 
ponera  grandis  (tip  of  tibia,   portion  of  the  tibia,  the  other  four  joints 

1  .earing  the  comb-like  spur,    £  -in  in  rrl      "f 

and  the  base  of  the  first  joint    forming  the  functional  loot.        ilie   Il'Ollt 

of  the  tarsus ;  cf.  fig.  75).   tibiae   are   furnished   with   a    beautiful 

A,  Inner,  B,  outer  aspect. 

combing  apparatus  (Fig.  57) 

Features  of  Ant-life. — In  order  that  the  reader  may  realise 
the  nature  of  ant-life  we  may  briefly  recount  its  more  usual  and 
general  features.  Numerous  eggs  are  produced  in  a  nest  by  one 
or  more  queens,  and  are  taken  care  of  by  workers.  These  eggs 
hatch  and  produce  helpless  maggots,  of  which  great  care  is 
taken  by  the  workers.  These  nurses  feed  their  charges  from 
their  own  mouths,  and  keep  the  helpless  creatures  in  a  fitting- 
state  by  transporting  them  to  various  chambers  in  conformity 
with  changes  of  temperature,  humidity,  and  so  on.  When  full 
grown  the  maggots  change  to  pupae.  In  some  species  the 
maggots  form  cocoons  for  themselves,  but  in  others  this  is  not 
the  case,  and  the  pupae  are  naked.1  After  a  brief  period  of 

1  The  pupae  and  cocoons  of  ants  are  usually  called  by  the  uninstructed,  "ants' 
eggs."     In  this  country  they  are  used  as  food  for  pheasants. 


iv  FORMICIDAE ANTS  135 

pupal  life  a  metamorphosis  into  the  perfect  Insect  occurs.  The 
creatures  then  disclosed  may  be  either  winged  or  wingless ;  the 
wingless  are  the  workers  and  soldiers — imperfect  females — the 
winged  are  males  or  females  fully  developed.  The  workers  re- 
main in  or  near  the  nest  they  were  produced  in,  but  the  winged 
individuals  rise  into  the  air  for  a  nuptial  flight,  often  in  great 
numbers,  and  couple.  When  this  is  accomplished  the  male 
speedily  dies,  but  the  females  cast  their  wings  and  are  ready  to 
enter  on  a  long  life  devoted  to  the  production  of  eggs.  From 
this  account  it  will  be  gathered  that  males  are  only  found  in 
the  nests  for  a  very  short  time ;  the  great  communities  consist- 
ing at  other  periods  entirely  of  the  two  kinds  of  females  and  of 
young.  The  imperfect  females  are  themselves  in  some  species 
of  various  kinds ;  each  kind  being  restricted,  more  or  less  com- 
pletely, to  a  distinct  kind  of  duty. 

No  Insects  are  more  familiar  to  us  than  ants ;  in  warm 
countries  some  of  them  even  invade  the  habitations  of  man,  or 
establish  their  communities  in  immediate  proximity  to  his 
dwellings.  Their  industry  and  pertinacity  have,  even  in  remote 
ages,  attracted  the  attention  and  admiration  of  serious  men  ;  some 
of  whom — we  need  scarcely  mention  Solomon  as  amongst  them— 
have  not  hesitated  to  point  out  these  little  creatures  as  worthy 
of  imitation  by  that  most  self-complacent  of  all  the  species  of 
animals,  Homo  sapiens. 

Observation  has  revealed  most  remarkable  phenomena 
in  the  lives  of  these  Insects.  Indeed,  we  can  scarcely  avoid 
the  conclusion  that  they  have  acquired  in  many  respects 
the  art  of  living  together  in  societies  more  perfectly  than 
our  own  species  has,  and  that  they  have  anticipated  us  in  the 
acquisition  of  some  of  the  industries  and  arts  that  greatly 
facilitate  social  life.  The  lives  of  individual  ants  extend  over  a 
considerable  number  of  years — in  the  case  of  certain  species  at 
any  rate — so  that  the  competence  of  the  individual  may  be 
developed  to  a  considerable  extent  by  exercise ;  and  one  genera- 
tion may  communicate  to  a  younger  one  by  example  the  arts 
of  living  by  which  it  has  itself  profited.  The  prolonged  life  of 
ants,  their  existence  in  the  perfect  state  at  all  seasons,  and  the 
highly  social  life  they  lead  are  facts  of  the  greatest  biological 
importance,  and  are  those  that  we  should  expect  to  be  accom- 
panied by  greater  and  wider  competence  than  is  usually  exhibited 


136  HYMENOPTERA 


CHAP. 


by  Insects.      There  can  indeed  be  little  doubt  that  ants  are  really 

t  a 

not  only  the  "  highest "  structurally  or  mechanically  of  all  Insects, 
but  also  the  most  efficient.  There  is  an  American  saying  to 
the  effect  that  the  ant  is  the  ruler  of  Brazil.  We  must  add  a 
word  of  qualification ;  the  competence  of  the  ant  is  not  like  that 
of  man.  It  is  devoted  to  the  welfare  of  the  species  rather  than  to 
that  of  the  individual,  which  is,  as  it  were,  sacrificed  or  specialised 
for  the  benefit  of  the  community.  The  distinctions  between  the 
sexes  in  their  powers  or  capacities  .are  astonishing,  and  those 
between  the  various  forms  of  one  sex  are  also  great.  The  differ- 
ence between  different  species  is  extreme ;  we  have,  in  fact,  the 
most  imperfect  forms  of  social  evolution  coexisting,  even  locally, 
with  the  most  evolute. 

These  facts  render  it  extremely  difficult  for  us  to  appreciate 
the  ant ;  the  limitations  of  efficiency  displayed  by  the  individual 
being  in  some  cases  extreme,  while  observation  seems  to  elicit 
contradictory  facts.  About  two  thousand  species  are  already 
known,  and  it  is  pretty  certain  that  the  number  will  reach  at 
least  five  thousand.  Before  passing  to  the  consideration  of  a 
selection  from  what  has  been  ascertained  as  to  the  varieties  of 
form,  and  of  habits  of  ants  we  will  deal  briefly  with  their  habita- 
tions and  polymorphism,  reserving  some  remarks  as  to  their 
associations  with  other  Insects  to  the  conclusion  of  this  chapter. 

Nests. — Ants  differ  greatly  from  the  other  Social  Hymenoptera 
in  the  nature  of  their  habitations.  The  social  bees  construct  cells 
of  wax  crowded  together  in  large  numbers,  and  the  wasps  do  the 
like  with  paper ;  the  eggs  and  young  being  placed,  each  one  in  a 
separate  cell,  the  combinations  of  which  form  a  comb.  Ants 
have,  however,  a  totally  different  system  ;  no  comb  is  constructed, 
and  the  larvae  are  not  placed  in  cells,  but  are  kept  in  masses  and 
are  moved  about  from  place  to  place  as  the  necessities  of  tempera- 
ture, air,  humidity  and  other  requirements  prompt.  The  habita- 
tions of  ants  are  in  all  cases  irregular  chambers,  of  which  there  is 
often  a  multiplicity  connected  by  galleries,  and  they  sometimes 
form  a  large  system  extending  over  a  considerable  area.  Thus 
the  habitations  of  ants  are  more  like  those  of  the  Termites  than 
those  of  their  own  allies  among  the  Hymenoptera.  They  are 
chiefly  remarkable  for  their  great  variety,  and  for  the  skilful 
manner  in  which  they  are  adapted  by  their  little  artificers  to 
particular  conditions.  The  most  usual  form  in  Europe,  is  a 


IV 


ANTS'  HABITATIONS 


'37 


number  of  subterranean  chambers,  often  under  the  shelter  of  a 
stone,  and  connected  by  galleries.  It  is  of  course  very  difficult  to 
trace  exactly  the  details  of  such  a  work,  because  when  excavations 
are  made  for  the  purposes  of  examination,  the  construction  becomes 
destroyed :  it  is  known,  however,  that  some  of  these  systems 
extend  to  a  considerable  depth  in  the  earth,  it  is  said  to  as  much 
as  nine  feet,  and  it  is  thought  the  object  of  this  is  to  have  access 
to  sufficiently  moist  earth,  for  ants  are  most  sensitive  to  variations 
in  the  amount  of  moisture ; 
a  quite  dry  atmosphere  is  in 
the  case  of  many  species  very 
speedily  fatal.  This  system 
of  underground  labyrinths 
is  sometimes  accompanied  by 
above-ground  buildings  con- 
sisting of  earth  more  or  less 
firmly  cemented  together  by 
the  ants ;  this  sort  of  dwell- 
ing is  inOSt  frequently  adopted  FlG.  58.— Portion  of  combined  nest  of  For- 
whell  the  soil  ill  which  the  '  aml  Solenopsis  fugax  (Alter 

nests  are  placed  is  sandy  ;  it 
is  probable  that  the  earth  is 
in  such  cases  fastened  together 
by  means  of  a  cement  pro- 
duced by  the  salivary  glands 
of  the  ants,  but  this  has  not 
been  determined  with  certainty  ;  vaulted  galleries  or  tunnels  of 
this  kind  are  constructed  by  many  species  of  ants  in  order  to 
* -liable  them  to  approach  desired  objects. 

In  South  America  Camponotus  ruftpes  and  other  species  that 
habitually  dwell  in  stumps,  in  certain  districts  where  they  are 
liable  to  inundations,  build  also  nests  of  a  different  nature  on 
trees  for  refuge  during  the  floods.  In  Europe,  a  little  robber-ant, 
Solenopsis  fugax,  constructs  its  dwelling  in  combination  with  that 
of  Fn' i/i  ir/f  f<i*ca  (Fig.  58),  in  such  a  manner  that  its  chambn> 
cannot,  on  account  of  the  small  size  of  the  orifices,  be  entered  by 
the  much  larger  Fur  mint.  Hence  the  robber  obtains  an  easy 
living  at  the  expense  of  the  larger  species.  The  Sauba  or  Sauva 
ants  of  South  America  (the  genus  Atta  of  some,  Oecodoma  of 
other  authors)  appear  to  be  most  proficient  in  the  art  of  sub- 


Forel.)  x  |.  f,  f,  Chambers  of  Formica, 
recognisable  by  the  coarser  shading ; 
s,  s',  chambers  of  the  Solenoftsis  (with 
finer  shading)  ;  s",  opening  in  one  of  the 
chambers,  the  entrance  to  one  of  the 
galleries  that  connects  the  chambers  of  the 
Solenopsis;  ic,  walls  forming  the  founda- 
tions of  the  nest  and  the  limits  of  the 
chambers. 


'38 


HYMENOPTERA 


CHAP. 


terranean  mining.     Their  systems  of  tunnels  and  nests  are  known 
to  extend  through  many  square  yards  of  earth,  and  it  is  said  on 
the  authority  of  Hamlet  Clark  that  one  species  tunnelled   under' 
the   bed  of  the   river  Parahyba  at  a  spot  where   it  was  as  broad 
as  the  Thames  at  London  Bridge. 

A  considerable  number  of  ants,  instead  of  mining  in  the 
ground,  form  chambers  in  wood;  these  are  usually  very  close  to 
one  another,  because,  the  space  being  limited,  galleries  cannot  be 
indulged  in.  Ctimponotus  ligniperdus  in  Europe,  and  0.  pennsyl- 
vanicus  in  North  America,  work  in  this  way. 

Our  British  Lasius  fuliginosus  lives  in  decayed  wood.  Its 
chambers  are  said  by  Forel  to  consist  of  a  paper-like  substance 
made  from  small  fragments  of  wood.  Cryptocerus  burrows  in 

branches.  Colobopsis  lives  in  a 
similar  manner,  and  Forel  in- 
forms us  that  a  worker  with 
a  large  head  is  kept  stationed 
within  the  entrance,  its  great  head 
acting  as  a  stopper ;  when  it  sees 


a  nest-fellow  desirous  of  entering 


the  nest,  this  animated  and  intel- 
ligent front-door  then  retreats  a 
little  so  as  to  make  room  for 
ingress  of  the  friend.  Forel  has 
observed  that  in  the  tropics  of 
America  a  large  number  of  species 
of  ants  live  in  the  stems  of  grass. 
There  is  also  quite  a  fauna  of 
ants  dwelling  in  hollow  thorns, 
in  spines,  on  trees  or  bushes,  or 
in  dried  parts  of  pithy  plants ; 
and  the  tropics  also  furnish  a 
number  of  species  that  make  nests 
of  delicate  paper,  or  that  spin 
together  by  means  of  silk  the 
leaves  of  trees.  One  eastern 
species — Polyrhachis  spiniycra — fabricates  a  gauze-like  web  of 
silk,  with  which  it  lines  a  subterranean  chamber  after  the 
manner  of  a  trap-door  spider. 

Some   species   of  ants  appear   to   lind  both   food   and   shelter 


Kii;.  .ri9. — Ant-plant,  Hydnophytwn  mon- 
taniim.     Java.     (After  Forel.) 


iv  ANTS  139 

entirely  on  the  tree  they  inhabit,  the  food  being  usually  sweet 
stuff  secreted  by  glands  of  the  plant.  It  is  thought  that  the 
ants  in  return  are  of  considerable  benefit  to  the  plant  by  defend- 
ing it  from  various  small  enemies,  and  this  kind  of  symbiosis  has 
received  much  attention  from  naturalists.  A  very  curious  con- 
dition exists  in  the  epiphytic  plants  of  the  genera  Myrmecodia 
and  Hydnophytum ;  these  plants  form  large  bulb-like  (Fig.  59) 
excrescences  which,  when  cut  into,  are  found  to  be  divided  into 
chambers  quite  similar  to  those  frequently  made  by  ants.  Though 
these  structures  are  usually  actually  inhabited  by  ants,  it  appears 
that  they  are  really  produced  by  the  plant  independent  of  the 
Insects. 

Variability  and  Polymorphism  of  Ants. — Throughout  the 
Hymenoptera  there  are  scattered  cases  in  which  one  of  the  sexes 
appears  in  dimorphic  form.  In  the  social  kinds  of  bees  and 
wasps  the  female  sex  exists  in  two  conditions,  a  reproductive 
one  called  queen,  and  an  infertile  one  called  worker,  the  limits 
between  the  two  forms  seeming  in  some  cases  (honey-bee)  to  be 
absolute  as  regards  certain  structures.  This  sharp  distinction 
in  structure  is  rare ;  while  as  regards  fertility  intermediate  con- 
ditions are  numerous,  and  may  indeed  be  induced  by  changing 
the  social  state  of  a  community.1  In  ants  the  phenomena  of  the 
kind  we  are  alluding  to  are  very  much  more  complex.  There  are 
no  solitary  ants ;  associations  are  the  rule  (we  shall  see  there  are 
one  or  two  cases  in  which  the  association  is  with  individuals  of 
other  species).  In  correlation  with  great  proclivity  to  socialism 
we  find  an  extraordinary  increase  in  the  variety  of  the  forms  of 
which  species  are  made  up.  In  addition  to  the  male  and  female 
individuals  of  which  the  species  of  Insects  usually  consist,  there 
are  in  ants  workers  of  various  kinds,  and  soldiers,  all  of  which 
are  modified  infertile  females.  But  in  addition  to  the  existence 
of  these  castes  of  infertile  females,  we  find  also  numerous  cases 
of  variability  or  of  dimorphism  of  the  sexual  individuals ;  and 
this  in  both  sexes,  though  more  usually  in  the  female.  Thus 
there  exists  in  ants  an  extraordinary  variety  in  the  polymorphism 
of  forms,  as  shown  by  the  table  on  p.  141,  where  several  very 
peculiar  conditions  are  recorded. 

The   complex   nature   of  these  phenomena  has  only  recently 

1  The  parthenogenetic  young  produced  by  worker  females  are  invariably  of  the 
male  sex. 


140  HYMENOPTERA  CHAP. 

become  known,  and  as  yet  has  been  but  little  inquired  into.  The 
difference  between  the  thoracic  structure  in  the  case  of  the  winged 
rind  wingless  females  of  certain  species  (Fig.  55,  and  in  vol.  v. . 
tiir.  .S-'39)  is  enormous,  but  in  other  species  this  difference  appears 
to  be  much  less.  The  ordinary  distinctions  between  the  queen- 
female  and  worker-females  appear  to  be  of  two  kinds;  firstly, 
that  the  former  is  winged,  the  latter  wingless  ; 1  and  secondly,  that 
the  former  possesses  a  receptaculum  seminis,  the  latter  does  not. 
In  a  few  cases  it  would  seem  that  the  dimorphism  of  winged 
;ind  wingless  forms  is  not  complete,  but  that  variability  exists. 
Intermediate  conditions  between  the  winged  and  wingless  forms 
are  necessarily  rare;  nevertheless  a  certain  number  have  already 
been  detected,  and  specimens  of  Lasius  aliemts  have  been  found 
with  short  wings.  In  rather  numerous  species  some  or  all  of 
the  fertile  females  depart  from  the  usual  state  and  have  no  wings  ; 
(a  similar  condition  is  seen,  it  will  be  recollected,  in  Mutillides 
and  Thynnides  of  the  neighbouring  family  Scoliidae).  A  di- 
morphism as  regards  wings  also  exists  in  the  male  sex,  though  it  is 
only  extremely  rarely  in  ants  that  the  males  are  wingless.  Never- 
less  a  few  species  exist  of  which  only  wingless  males  have  been 
found,  and  a  few  others  in  which  both  winged  and  wingless 
individuals  of  this  sex  are  known  to  occur.  The  wingless  males  of 
course  approach  the  ordinary  workers  ( ==  infertile  wingless  females) 
in  appearance,  but  there  is  not  at  present  any  reason  for 
supposing  that  they  show  any  diminution  in  their  male  sexual 
characters.  The  distinction  between  workers  and  females  as 
based  on  the  existence  or  non-existence  of  a  receptaculum  seminis 
has  only  recently  become  known,  and  its  importance  cannot  yet 
be  estimated.  The  adult,  sexually  capable,  though  wingless  forms, 
are  called  ergatoid,  because  they  are  similar  to  workers  ('E^ar?;?, 
a  worker).2 

1  The  student  must  recollect  that  the  winged  female  ants  cast  their  wings 
previously  to  assuming  the  social  life.  The  winglessness  of  these  females  is  a 
totally  different  phenomenon  from  that  we  here  allude  to. 

-  See  Fun  1,  Verh.  Ges.  deutsch.  Xalurf.  Ixvi.  1894,  2,  pp.  142-147  ;  and  Emery 
/>'/<>/.  ( '<  nt i'ii II, I.  xiv.  1S<)1,  p.  53.  The  term  ergatoid  applies  to  both  sexes  ;  a  species 
with  worker-like  female  is  ergatogynous  ;  with  a  worker-like  male  ergatandrous. 


IV 


ANTS 


141 


Table  of  the  Chief  Forms  of  Polymorphism  in  Ants. 


1-9 

•v 

0 

. 

M 
g 

| 

S 

""S  ^ 

,. 

£M 

•—     * 

flj     * 

^  S  S 

o 

°  c    . 

Cj   <v* 

\*~  ^ 

^j   ^ 

.5  3;  T~ 

"S 

--  ^-  '— 

Xame  of  Ants. 

^"5 

^ 

T  s 

sl 

"S^^ 

"  &•  c 

r-  :^   "~ 

a 

O  a; 

i'l 

1  i^ 

t,'    ,         t. 

'•5 

§>s 

^ 

% 

C  +3  rt 

is 

o 

C  J 

O 

a 

o 

H 

M^ 

CO 

^ 

~ 

Miinaica,  Polyrhachis,  ~\ 

etc. 

"*" 

Camponotus,        Atta,\ 

Phcidologeton,  etc.  .  J 

"*" 

Pheidole,   subg.    Colo-} 

bopsis      .         .         .  / 

EC  i  t  o  n     h  a  m  atu  m,  "j 

E.   quadriglume,  - 

+ 

+ 

+  • 

+ 

+ 

E.  foreli,  etc.  . 

Cryptocerus         disco-  \ 

ccplmlus,  etc.            .  J 

+ 

+ 

+ 

Strongylognathus 

+ 

+ 

+ 

Carebara   and    Solen-  ~j 

opsis     (except      S.  r 

+ 

+ 

+ 

geminata)        .          .  | 

Solenopsis  geminata   . 

+ 

+ 

+ 

+ 

f    + 

Formica  rufa     . 

+ 

+ 

-   excep- 

(  tionally 

Ponera  punctatissima 

+ 

+ 

+ 

+ 

Ponera  ergatandria    . 

? 

+ 

+ 

+ 

Cardiocondyla  cmeryi 

+ 

+ 

+ 

+ 

C.     wroughtonii    and  ) 

, 

C.  stambuloffi  .         .  j 

Formicoxentis        niti-  ~\ 

- 

dulus      .         .         .  J 

+ 

+ 

Tomognathus 

+ 

+ 

+ 

Odontomachus       Jtae-} 

( 

. 

+ 

matodcs  . 

+ 

+ 

'   excep- 
[  tionally 

Polyergus  . 

+ 

+ 

+ 

Dorylus,       Anomma,} 

+ 

+ 

Eciton  part.    . 

Aenictus    . 

-f- 

+ 

Leptogenys,      Dia-\ 

, 

camma    .         .         .j 

Myrmecocystus      mel-} 

1    and 

ligcr,  M.  mexicanusj 

"j  honey- 
\_  pots 

f     + 

f  + 

Ponera  eduardi  . 

+ 

+ 

1    eyes 
[  large 

I'Vi-s 

[obsolete 

Ancr  gates  . 

+ 

+ 

In  addition  to  the  above  there  are  apparently  cases  of  females  with  post-meta- 
niorphic  growth  in  Dorylides,  but  these  have  not  yet  been  the  subject  of  investiga- 
tion. 


14-  HYMENOPTERA  CHAI'. 

Much  has  been  written  about  the  mode  in  which  the  variety 
of  forms  of  a  single  species  of  ant  is  produced.  As  to  this  there 
exists  but  little  actual  observation  or  experiment,  and  the 
subject  has  been  much  complicated  by  the  anxiety  of  the  writers 
to  display  the  facts  in  a  manner  that  will  support  some  general 
theory.  Dewitz  was  of  opinion  that  workers  and  queens  of  ants 
were  produced  from  different  kinds  of  eggs.  This  view  finds 
but  little  support  among  recent  writers.  Hart  in  recording  the 
results  of  his  observations  on  the  parasol  ant  (of  the  genus  Attct) 
—one  of  the  species  in  which  polymorphism  is  greatest — says1 
that  these  observations  prove  that  "ants  can  manufacture  at 
will,  male,  female,  soldier,  worker  or  nurse,"  but  he  has  not 
determined  the  method  of  production,  and  lie  doubts  it  being 
"  the  character  of  the  food."  There  is,  however,  a  considerable 
1  Hjdy  of  evidence  suggesting  that  the  quality  or  quantity  of  the 
food,  or  both  combined,  are  important  factors  in  the  treatment 
by  which  the  differences  are  produced.  The  fact  that  the  social 
Insects  in  which  the  phenomena  of  caste  or  polymorphism  occur, 
though  belonging  to  very  diverse  groups,  all  feed  their  young,  is 
of  itself  very  suggestive.  When  we  add  to  this  the  fact  that  in 
ants,  where  the  phenomena  of  polymorphism  reach  their  highest 
complexity,  the  food  is  elaborated  in  their  own  organs  by  the 
feeders  that  administer  it,  it  appears  probable  that  the  means 
of  producing  the  diversity  may  be  found  herein.  Wasmann  has 
pointed  out  that  the  ants'-nest  beetle,  Lomechusa,  takes  much 
food  from  the  ants,  and  itself  destroys  their  young,  and  that  in 
nests  where  Lomeclmsa  is  abundant  a  large  percentage  of  erga- 
togynous  forms  of  the  ants  are  produced.  He  attributes  this  to 
the  fact  that  the  destruction  of  the  larvae  of  the  ant  by  the 
beetle  brings  into  play  the  instinct  of  the  ants,  which  seek  to 
atone  for  the  destruction  by  endeavouring  to  produce  an 
increased  number  of  fertile  forms  ;  many  ergatogynous  individuals 
being  the  result.  This  may  or  may  not  be  the  case,  but  it  is 
clear  that  the  ants'  instinct  cannot  operate  without  some 
material  means,  and  his  observation  adds  to  the  probability  that 
this  means  is  the  food  supply,  modified  either  qualitatively  or 
quantitatively. 

The    existence    of    these    polymorphic     forms     led     Herbert 
Spencer   to  argue   that  the   form  of  an  animal   is  not  absolutely 

1   Nature  li.  1894,  p.  12:.. 


iv  ANTS  143 

determined  by  those  "  Aulau'en  "  or  rudiments  that  Weismann 
and  his  school  consider  to  be  all  important  in  determining  the 
nature  or  form  of  the  individual,  for  if  this  were  the  case,  how 
can  it  be,  he  asked,  that  one  egg  may  produce  either  a  worker, 
nurse,  soldier  or  female  ant  ?  To  this  "Wasmann  (who  continued 
the  discussion)  replied  by  postulating  the  existence  of  double,  triple 
or  numerous  rudiments  in  each  egg,  the  treatment  the  egg  receives 
merely  determining  which  of  these  rudiments  shall  undergo  de- 
velopment.1 Forel  seems  to  have  adopted  this  explanation  as  being 
the  most  simple.  The  probability  of  Weismann's  hypothesis  being 
correct  is  much  diminished  by  the  fact  that  the  limit  between  the 
castes  is  by  no  means  absolute.  In  many  species  intermediate  forms 
are  common,  and  even  in  those  in  which  the  castes  are  believed  to 
be  quite  distinct,  intermediate  forms  occur  as  very  rare  excep- 
tions.2 Emery  accounts 3  for  the  polymorphism,  without  the 
assistance  of  the  Weismannian  hypothetical  compound  rudiments, 
by  another  set  of  assumptions  ;  viz.  that  the  phenomenon  has 
been  gradually  acquired  by  numerous  species,  and  that  we  see  it 
in  various  stages  of  development ;  also  that  variation  in  nutrition 
does  not  affect  all  the  parts  of  the  body  equally,  but  may  be 
such  as  to  carry  on  the  development  of  certain  portions  of  the 
organisation  while  that  of  other  parts  is  arrested.  Speaking 
broadly  we  may  accept  this  view  as  consistent  with  what  we 
know  to  be  the  case  in  other  Insects,  and  with  the  phenomena  of 
post-embryonic  development  in  the  class.  But  it  must  be  ad- 
mitted that  our  knowledge  is  at  present  quite  inadequate  to 
justify  the  formulation  of  any  final  conclusions. 

The  geological  record  of  Formicidae  is  not  quite  what  we 
should  have  expected.  They  are  amongst  the  earliest  Hymen- 
optera ;  remains  referred  to  the  family  have  been  found  in  the 
Lias  of  Switzerland  and  in  the  English  Purbecks.  In  Tertiary 
times  Formicidae  appear  to  have  been  about  the  most  abundant 
of  all  Insects.  At  Florissant  they  occur  in  thousands  and  form 
in  individuals  about  one-fourth  of  all  the  Insects  found  there. 
They  have  also  been  met  with  numerously  in.  the  European 
Tertiaries,  and  Mayr  studied  no  less  than  1500  specimens  found 

1  B'wl.  Ccntralbl.  xv.  1895,  p.  640. 

2  Prof.  Forel  has  favoured  the  writer  by  informing  him  of  several  cases  of  these 
rare  intermediate  forms  he  has  himself  detected. 

3  Biol.  CcntralU.  xiv.  1894,  p.  53. 


144  HYMENOPTERA  CHAP. 

in  amber.      Formicides  and  Myrmicides  are  more  abundant   than 
Ponerides,  but   this    latter   group   has   the    larger    proportion    of 
extinct  genera ;   conditions  but  little  dissimilar  to  those  existing  • 
at  present. 

Classification  of  Ants. — Ants  are  considered  by  many  ento- 
mologists to  form  a  series  called  Heterogyna.  They  can, 
however,  be  scarcely  considered  as  more  than  a  single  family, 
Formicidae,  so  that  the  serial  name  is  superfluous.  Their 
nearest  approach  to  other  Aculeates  is  apparently  made,  by 
AmUyopone,  to  certain  Mutillides  (e.g.  Apterogynct)  and  to  the 
Thyiinides,  two  divisions  of  Scoliidae.  Emery  considers  Dory- 
lidt'.s  rather  than  Amblyoponides  to  be  the  most  primitive  form 
of  ants,  but  we  are  disposed  to  consider  Forel's  view  to  the  effect 
we  have  above  mentioned  as  more  probably  correct.  The  point 
is,  however,  very  doubtful.  The  condition  of  the  peduncle  is  in 
both  the  sub-families  we  have  mentioned  very  imperfect  compared 
with  that  of  other  ants.  Both  these  sub-families  are  of  very 
small  extent  and  very  imperfectly  known.  We  shall  also 
follow  Forel  in  adopting  six  sub-families,  Camponotides,  Dolicho- 
derides,  Myrmicides,  Ponerides,  Dorylides,  and  Amblyoponides. 
Emery  rejects  the  Amblyoponides  as  being  merely  a  division  of 
the  Ponerides.  This  latter  group  displays  the  widest  relations 
of  all  the  sub-families,  and  may  be  looked  on  as  a  sort  of  central 
form.  The  Camponotides  and  Dolichoderides  are  closely  allied, 
and  represent  the  highest  differentiation  of  the  families  in  one 
direction.  The  Myrmicides  are  also  highly  differentiated,  but 
are  not  allied  to  the  Camponotides  and  Dolichoderides.1 

Sub-Fam.  1.  Camponotides. — Hind  body  furnished  with  lni.t  one 
constriction,  so  that  only  a  single  scale  or  node  exists  on  the 
pedicel.  Poison-sac  forming  a  cushion  of  convolutions,  on 
which  is  situate  the  modified  sting,  which  forms  merely  an 
ejaculatory  orifice  for  the  poison. 

The  members  of  this  very  extensive  division  of  ants  can  be 
readily  distinguished  from  all  others,  except  the  Dolichoderides, 
by  the  absence  of  a  true  sting,  and  by  the  peculiar  form  of  the  hind 
body ;  this  possesses  only  a  single  scale  at  the  base,  and  has  no 

1  Forel's  latest  views  on  this  subject  will  be  found  in  the  Ann.  Sac.  cnt.  Bdgique 
xxxvii.  1893,  p.  161  ;  the  very  valuable  paper  by  Emery,  in  ZooL  Jahrb.  Syst. 
viii.  1896,  p.  760. 


iv  ANTS — CAMPONOTIDES  145 

constriction  at  all  on  the  oval,  convex  and  compact  mass  of  the 
abdomen  behind  this.  The  cloacal  orifice  is  circular,  not,  as  in 
other  ants,  transverse.  These  characters  are  accompanied  by  a 
difference  in  habits.  The  Camponotides,  though  they  do  not 
sting,  produce  poison  in  large  quantity,  and  eject  it  to  some  dis- 
tance. Hence,  if  two  specimens  are  confined  in  a  tube  they  are 
apt  to  kill  one  another  by  the  random  discharges  they  make. 
Janet  suggests  that  in  order  to  neutralise  the  effect  of  this  very 
acid  poison,  they  may  have  some  means  of  using,  when  they  are 
in  their  natural  abodes,  the  alkaline  contents  of  a  second  gland 
with  which  they  are  provided.  We  shall  mention  the  characters 
by  which  the  Camponotides  are  distinguished  from  the  small 
sub-family  Dolichoderides  when  we  deal  with  the  latter. 

The  sub -family  includes  800  or  more  species.  Camponotus 
itself  is  one  of  the  most  numerous  in  species  of  all  the  genera  of 
Formicidae,  and  is  distributed  over  most  parts  of  the  earth.  We 
have  no  species  of  it  in  Britain,  but  in  the  south  of  Europe  the 
Camponotus  become  very  conspicuous,  and  may  be  seen  almost 
everywhere  stalking  about,  after  the  fashion  of  our  British  wood- 
ant,  Formica  n/fa,  which  in  general  appearance  Camponotus  much 
resembles. 

Until  recently,  the  manner  in  which  fresh  nests  of  ants  were 
founded  was  unknown.  In  established  nests  the  queen-ant  is 
fed  and  tended  by  the  workers,  and  the  care  of  the  helpless  larvae 
and  pupae  also  devolves  entirely  on  the  workers,  so  that  the 
queens  are  relieved  of  all  functions  except  that  of  producing  eggs. 
It  seemed  therefore  impossible  that  a  fresh  nest  could  be  estab- 
lished by  a  single  female  ant  unless  she  were  assisted  by  workers. 
The  mode  in  which  nests  are  founded  has,  however,  been  recently 
demonstrated  by  the  observations  of  Lubbock,  M'Cook,  Adlerz, 
and  more  particularly  by  those  of  Blochmann,  who  was  successful 
in  observing  the  formation  of  new  nests  by  Camponotus  ligni- 
perdus  at  Heidelberg.  He  found  under  stones  in  the  spring 
many  examples  of  females,  either  solitary  or  accompanied  only 
by  a  few  eggs,  larvae  or  pupae.  Further,  he  was  successful  in 
getting  isolated  females  to  commence  nesting  in  confinement,  and 
observed  that  the  ant  that  afterwards  becomes  the  queen,  at  first 
carries  out  by  herself  all  the  duties  of  the  nest :  beginning  by 
making  a  small  burrow,  she  lays  some  eggs,  and  when  these  hatch, 
feeds  and  tends  the  larvae  and  pupae  ;  the  first  specimens  of  these 

VOL.  VI  L 


146  HYMENOPTERA 


CHAP. 


latter  that  become  perfect  Insects  are  workers  of  all  sizes,  and 
at  once  undertake  the  duties  of  tending  the  young  and 
feeding  the  mother,  who,  being  thus  freed  from  the  duties  of 
nursing  and  of  providing  food  while  she  is  herself  tended  and 
fed,  becomes  a  true  queen-ant.  Thus  it  seems  established  that 
in  the  case  of  this  species  the,  division  of  labour  found  in  the 
complex  community,  does  not  at  first  exist,  but  is  correlative  with 
increasing  numbers  of  the  society.  Further  observations  as  to  the 
growth  of  one  of  these  nascent  communities,  and  the  times  and 
conditions  under  which  the  various  forms  of  individuals  composing 
a  complete  society  first  appear,  would  be  of  considerable  interest. 

An  American  species  of  the  same  genus,  C.  pennsylvanicus, 
the  carpenter-ant,  establishes  its  nests  in  the  stumps  of  trees. 
Leidy  observed  that  solitary  females  constructed  for  themselves 
cells  in  the  wood  and  closed  the  entrances,  and  that  each  one  in 
its  solitary  confinement  reared  a  small  brood  of  larvae.  The 
first  young  produced  in  this  case  are  said  to  be  of  the  dwarf 
caste,  and  it  was  thought  by  the  observer  that  the  ant  remained 
not  only  without  assistance  but  also  without  food  during  a  period 
of  some  weeks,  and  this  although  she  was  herself  giving  food  to 
the  larvae  she  was  rearing. 

Adlerz  states  that  the  females  or  young  queens  take  no  food 
while  engaged  in  doing  their  early  work,  and  that  the  large 
quantity  of  fat-body  they  possess  enables  them  to  undergo  several 
months  of  hunger.  In  order  to  feed  the  young  larvae  they  use 
their  own  eggs  or  even  the  younger  larvae.  It  is  to  the  small 
quantity  of  food  rather  than  to  its  nature  that  he  attributes  the 
small  size  of  the  first  brood  of  perfect  workers.  M.  Janet :  has 
recently  designed  an  ingenious  and  simple  apparatus  for  keeping 
ants  in  captivity.  In  one  of  these  he  placed  a  solitary  female  of 
Lasiii*  (t/ic/ius,  unaccompanied  by  any  workers  or  other  assistants. 
;tii(l  he  found  at  the  end  of  98  days  that  she  was  taking  care  of 
a  progeny  consisting  of  50  eggs,  2  larvae,  5  pupae  in  cocoons,  5 
without  cocoons.  On  the  102nd  day  workers  began  to  emerge 
from  the  cocoons.2  From  these  observations  it  is  evident  that 
the  queen-ant,  when  she  begins  her  nest,  lives  under  conditions 
extremely  different  from  those  of  the  royal  state  she  afterwards 
reaches. 

1  Ann.  Sod.  cut.  France,  1893,  p.  467. 
z  Ann.  Soc.  cat.  France,  1893,  JJii/L  p.  cclxiv. 


JV 


ANTS — CAMPONOTIDES 


147 


In  many  kinds  of  ants  the  full-grown  individuals  are  known 
to  feed  not  only  the  larvae  by  disgorging  food  from  their  own 
mouths  into  those  of  the  little  grubs,  but  also  to  feed  one  another. 
This  has  been  repeatedly  observed,  and  Forel  made  the  fact  the 
subject  of  experiment  in  the  case  of  Camponotus  ligniperdus. 
He  took  some  specimens  and  shut  them  up  without  food  for 
several  days,  and  thereafter  supplied  some  of  them  with  honey, 
stained  with  Prussian  blue ;  being  very  hungry,-  they  fed  so 
greedily  on  this  that  in  a  few  hours  their  hind  bodies  were  dis- 
tended to  three  times  their  previous  size.  He  then  took  one  of 
these  gorged  individuals  and  placed  it  amongst  those  that  had 
not  been  fed.  The  replete  ant  wras  at  once  explored  by  the 
touches  of  the  other  ants  and  surrounded,  and  food  was  begged 
from  it.  It  responded  to  the  demands  by  feeding  copiously  a 
small  specimen  from  its  mouth  :  when  this  little  one  had  received 
a  good  supply,  it  in  turn  communicated  some  thereof  to  other 
specimens,  while  the  original  well-fed  one  also  supplied  others, 
and  thus  the  food  was  speedily  distributed.  This  habit  of  receiv- 
ing and  giving  food  is  of  the  greatest  importance  in  the  life- 
history  of  ants,  and  appears  to  be  the  basis  of  some  of  the 
associations  that,  as  wre  shall  subsequently  see,  are  formed  with 
ants  by  numerous  other  Insects. 

OecopliyllcL  smaragdina,  a  common  ant  in  Eastern  Asia,  forms 
shelters  on  the  leaves  of  trees  by  curling  the  edo;es  of  leaves 

t/  O  O 

and  joining  them  together.  In  doing  this  it  makes  use  of  an 
expedient  that  would  not  be  believed  had  it  not  been  testified  by 
several  competent  and  independent  witnesses.  The  perfect  ant 
has  no  material  with  which 
to  fasten  together  the  edges 
it  curls ;  its  larva,  how- 
ever, possesses  glands  that 
secrete  a  supply  of  material 
fur  it  to  form  a  cocoon 
with,  and  the  ants  utilise 
the  larvae  to  effect  their 
purpose.  Several  of  them 
combine  to  hold  the  foliage  in  the  desired  position,  and  while 
they  do  so,  other  ants  come  up,  each  one  of  which  carries  a 
larva  in  its  jaws,  applies  the  mouth  of  the  larva  to  the  parts 
where  the  cement  is  required,  and  makes  it  disgorge  the  sticky 


FIG.  60. — Oecoplrylla  smarciyiUna.     Worker 
using  a  larva  for  spinning. 


148  HYMENOPTERA  CHAP. 

material.  Our  figure  is  taken  from  a  specimen  (for  which  we 
are  indebted  to  Mr.  E.  E.  Green)  that  was  captured  in  the  act 
of  bearing  a  larva. 

Formic tt  ri'ftt,  the  Red-ant,  Wood-ant,  or  Hill-ant,  is  in  this 
country  one  of  the  best-known  members  of  the  Formicidae.  It 
frequents  woods,  especially  such  as  are  composed,  in  whole  or 
part,  of  conifers,  where  it  forms  large  mounds  of  small  sticks, 
straws,  portions  of  leaves,  and  similar  material.  Although  at 
first  sight  such  a  nest  may  appear  to  be  a  chaotic  agglomeration, 
yet  examination  reveals  that  it  is  arranged  so  as  to  leave  many 
spaces,  and  is  penetrated  by  galleries  ramifying  throughout  its 
structure.  These  mound-nests  attain  a  considerable  size  when  the 
operations  of  the  industrious  creatures  are  not  interfered  with,  or 
their  work  destroyed,  as  it  too  often  is,  by  ignorant  or  mischievous 
persons.  They  may  reach  a  height  of  three  feet  or  near  it,  and 
a  diameter  of  twice  that  extent.  The  galleries  by  which  the 
heaps  are  penetrated  lead  down  to  the  earth  below.  From  the 
mounds  extend  in  various  directions  paths  constantly  traversed 
by  the  indefatigable  ants.  M'Cook  observed  such  paths  in  the 
Trossachs ;  they  proceed  towards  the  objects  aimed  at  in  lines 
so  straight  that  he  considers  they  must  be  the  result  of  some 
sense  of  direction  possessed  by  the  ants  ;  as  it  is  impossible  to 
suppose  they  could  perceive  by  the  sense  of  sight  the  distant 
objects  towards  which  the  paths  were  directed :  these  objects  in 
the  case  M'Cook  describes  were  oak-trees  up  which  the  ants 
ascended  in  search  of  Aphides. 

M'Cook  further  observed  that  one  of  the  oak-trees  was  reached 
by  individuals  from  another  nest,  and  that  each  of  the  two  parties 
was  limited  to  its  own  side  of  the  tree,  sentinels  being  placed  on 
the  limits  to  prevent  the  trespassing  of  an  intruder ;  he  also 
noticed  that  the  ants  saw  an  object  when  the  distance  became 
reduced  to  about  an  inch  and  a  half  from  them.  This  species  is 
considered  to  be  wanting  in  individual  courage  ;  but  when  acting 
in  combination  of  vast  numbers  it  does  so  with  intelligence  and 
success.  It  does  not  make  slaves,  but  it  has  been  observed  by 
Bignell  and  others  that  it  sometimes  recruits  its  numbers  by 
kidnapping  individuals  from  other  colonies  of  its  own  species. 
Its  nests  are  inhabited  by  forty  or  fifty  species  of  guests  of  various 
kinds,  but  chiefly  Insects.  Another  ant,  Myrmica  laevinodis, 
sometimes  lives  with  it  in  perfect  harmony,  and  Formicdxenus 


iv  CAMPONOTIDES— SLAVE-MAKING  ANTS  149 

nilididus  lives  only  with  F.  rufa.  Amongst  the  most  peculiar 
of  its  dependants  we  may  mention  large  beetles  of  the  genera 
Cetonia  and  Clytlira,  which  in  their  larval  state  live  in  the 
hills  of  the  wood-ant.  It  is  probable  that  they  subsist  on  some 
of  the  vegetable  matter  of  which  the  mounds  are  formed.  Adlerz 
has  given  some  attention  to  the  division  of  labour  amongst  the 
different  forms  of  the  workers  of  ants,  and  says  that  in  F.  rufa  it 
is  only  the  bigger  workers  that  carry  building  and  other  materials, 
the  smaller  individuals  being  specially  occupied  in  the  discovery 
of  honey -dew  and  other  Aphid  products.  In  Camponotus  it 
would  appear,  on  the  other  hand,  that  the  big  individuals  leave 
the  heavy  work  to  be  performed  by  their  smaller  fellows. 

The  wood-ant  and  its  near  allies  have  been,  and  indeed  still 
are,  a  source  of  great  difficulty  to  systematists  on  account  of  the 
variation  that  occurs  in  the  same  species,  and  because  this  differs 
according  to  locality.  Our  European  F.  rufa  has  been  supposed 
to  inhabit  North  America,  and  the  interesting  accounts  pub- 
lished by  M'Cook  of  the  mound-making  ant  of  the  Alleghanies 
were  considered  to  refer  to  it.  This  Insect,  however,  is  not  F. 
rufa,  as  WAS  supposed  by  M'Cook,  but  F.  exsectoides,  Forel.  It 
forms  colonies  of  enormous  extent,  and  including  an  almost  in- 
credible number  of  individuals.  In  one  district  of  about  fifty 
acres  there  was  an  Ant  City  containing  no  less  than  1*700  of 
these  large  ant-hills,  each  one  teeming  with  life.  It  was  found 
by  transferring  ants  from  one  hill  to  another  that  no  hostility 
whatever  existed  between  the  denizens  of  different  hills  ;  the 
specimens  placed  on  a  strange  hill  entered  it  without  the  least 
hesitation.  Its  habits  differ  in  some  particulars  from  those  of 
its  European  congener  ;  the  North  American  Insect  does  not  close 
the  formicary  at  night,  and  the  inquilines  found  in  its  nest  are 
very  different  from  those  that  live  with  F.  rufa  in  Europe. 
Whether  the  typical  wood-ant  occurs  in  North  America  is 
doubtful,  but  there  are  races  there  that  doubtless  belong  to 
the  species. 

F.  sanguinea  is  very  similar  in  appearance  to  its  commoner 
congener  F.  rufa,  and  is  the  only  slave-making  ant  we  possess  in 
lUitain.  This  species  constructs  its  galleries  in  banks,  and  is 
of  very  courageous  character,  carrying  out  its  military  operations 
with  much  tactical  ability.  It  is  perfectly  able  to  live  without 
the  assistance  of  slaves,  and  very  frequently  does  so  :  indeed  it 


HYMENOPTERA  CHAP. 


has  been  asserted  that  it  is  in  our  own  islands  (where,  however, 
it  is  comparatively  rare)  less  of  a  slave-owner  than  it  is  in 
Southern  Europe,  but  this  conclusion  is  very  doubtful.  It  ap- 
pears when  fighting  to  be  rather  desirous  of  conquering  its 
opponents  by  inspiring  terror  and  making  them  aware  of  its 
superiority  than  by  killing  them ;  having  gained  a  victory  it 
will  carry  off  the  pupae  from  the  nest  it  has  conquered  to  its 
own  abode,  and  the  ants  of  the  stranger-species  that  develop  from 
these  pupae  serve  the  conquerors  faithfully,  and  relieve  them  of 
much  of  their  domestic  duties.  The  species  that  F.  sanguinea. 
utilises  in  this  way  in  England  are  F.  fusca,  F.  cunicularia,  and 
possibly  Lasius  flatus.  Huber  and  Forel  have  given  graphic 
accounts  of  the  expeditions  of  this  soldier-ant.  In  the  mixed 
colonies  of  F.  sanguinea  and  F.  fusca  the  slaves  do  most  of  the 
house-work,  and  are  more  skilful  at  it  than  their  masters.  Adlerz 
says  that  one  of  the  slaves  will  accomplish  twice  as  much  work 
of  excavation  in  the  same  time  as  the  slave-owner ;  these  latter 
being  lazy  and  fond  of  enjoyment,  while  the  slaves  are  very 
industrious. 

Polyergus  rv/escens,  an  European  ant  allied  to  Formica,  is 
renowned  since  the  time  of  Huber  (1810)  as  the  slave-making 
or  Amazon  ant.  This  creature  is  absolutely  dependent  on  its 
auxiliaries  for  its  existence,  and  will  starve,  it  is  said,  in  the 
midst  of  food  unless  its  servitors  are  there  to  feed  it.  "Wasmann, 
however,  states  that  PO////-/V///.S  dues  possess  the  power  of 

feeding  itself  to  a  certain  extent.  Be 
this  as  it  may,  the  qualities  of  this  ant 
as  warrior  are  superb.  When  an  indi- 
vidual is  fighting  alone  its  audacity  is 
splendid,  and  it  will  yield  to  no  superi- 
ority of  numbers  ;  when  the  creatures  are 
acting  as  part  of  an  army  the  individual 
boldness  gives  place  to  courage  of  a  more 
suitable  sort,  the  ants  then  exhibiting  the 

FIG.  61.— Head  of  Polyergws     aet  of  retreating  or  making  flank  move- 
nifcscens.     (After  Andre. )  J~, 

ments  when  necessary.      It  a  Jrolyergus 

that  is  acting  as  a  member  of  a  troop  finds  itself  isolated,  and 
in  danger  of  being  overpowered,  it  has  then  no  hesitation  in 
seeking  safety  even  by  flight.  This  species  is  provided  with 
mandibles  of  a  peculiar  nature  :  they  are  not  armed  with  teeth, 


iv  CAMPONOTIDES SLAVE-MAKING  ANTS  I  5  I 

but  are  pointed  and  curved  ;  they  are  therefore  used  after  the 
manner  of  poignards,  and  when  the  ant  attacks  a  foe  it  seizes 
the  head  between  the  points  of  these  curved  mandibles,  and  driv- 
ing them  with  great  force  into  the  brain  instantly  paralyses  the 
victim. 

Mandibles  of  this  shape  are  evidently  unfitted  for  the  purposes 
of  general  work,  they  can  neither  cut,  crush,  nor  saw,  and  it  is 
not  impossible  that  in  their  peculiar  shape  is  to  be  found  the 
origin  of  the  peculiar  life  of  Polyergus :  we  find  similar  mandi- 
bles reappearing  amongst  the  aberrant  Dorylides,  and  attaining  a 
maximum  of  development  in  the  ferocious  Eciton ;  they  also 
occur,  or  something  like  them,  in  a  few  aberrant  Myrmicides ; 
and  in  the  male  sex  of  many  other  ants,  which  sex  exercises  no 
industrial  arts,  this  sort  of  mandible  is  present. 

The  ants  that  Polyergus  usually  attacks  in  order  to  procure  slaves 
are  Formica fusca  and  F.fusca,  race  auricularia  ;  after  it  has  routed 
a  colony  of  one  of  these  species,  P.  rufescens  pillages  the  nest  and 
carries  off  pupae  and  some  of  the  larger  larvae  to  its  own  abode. 
When  the  captives  thus  deported  assume  the  imago  state,  they 
are  said  to  commence  working  just  as  if  they  were  in  their  own 
houses  among  their  brothers  and  sisters,  and  they  tend  their 
captors  as  faithfully  as  if  these  were  their  own  relatives  :  possibly 
they  do  not  recognise  that  they  are  in  unnatural  conditions,  and 
may  be  quite  as  happy  as  if  they  had  never  been  enslaved.  The 
servitors  are  by  no  means  deficient  in  courage,  and  if  the  place 
of  their  enforced  abode  should  be  attacked  by  other  ant-enemies 
they  defend  it  bravely.  The  fact  that  P.  ru/escens  does  not  feed 
its  larvae  has  been  considered  evidence  of  moral  degeneration, 
but  it  is  quite  possible  that  the  Insect  may  be  unable  to  do  so 
on  account  of  some  deficiency  in  the  mouth -parts,  or  other 
similar  cause.  The  larvae  of  ants  are  fed  by  nutriment  regurgi- 
tated from  the  crop  of  a  \vorker  (or  female),  and  applied  to  the 
excessively  minute  mouth  of  the  helpless  grub  :  for  so  delicate 
a  process  to  be  successfully  accomplished,  it  is  evident  that  a 
highly  elaborated  and  specialised  arrangement  of  the  mouth- 
parts  must  exist,  and  it  is  by  no  means  improbable  that  the 
capacity  of  feeding  its  young  in  true  ant-fashion  is  absent  in 
Polyergus  for  purely  mechanical  reasons. 

M'Cook  states  that  the  North  American  ant,  7Wy/v///x  />/<  idus, 
which  some  entomologists  consider  to  be  merely  a  variety  of 


152 


IIYMENOPTERA 


CHAP. 


the  European  species,  makes  slaves  of  Formica  scJiaufussi,  itself 
does  no  work,  and  partakes  of  food  only  when  fed  by  its  servi- 
tors. He  did  not,  however,  actually  witness  the  process  of  feed- 
ing. AVhen  a  migration  takes  place  the  servitors  deport  both 
the  males  and  females  of  P.  hi.cidus.  M'Cook  adds  that  the 
servitors  appear  to  be  really  mistresses  of  the  situation,  though 
they  avail  themselves  of  their  power  only  by  working  for  the 
advantage  of  the  other  species. 

The  honey-ant  of  the  United  States  and  Mexico  has  been  in- 
vestigated by   M'Cook  and  others;   the    chief  peculiarity  of  the 

species  is  that  certain  individuals  are 
charged  with  a,  sort  of  honey  till  they 
become  enormously  distended,  and  in  fact 
serve  as  leather  bottles  for  the  storage 
of  the  fluid.  The  species  Myrmecocyslus 
liortideorum  and  M.  mclliger,  are  mode- 
rate-sized Insects  of  subterranean  habits, 
the  entrance  to  the  nest  of  M.  1 1  or  tide  or  u  in 
being  placed  in  a  small  raised  mound. 
The  honey  is  the  product  of  a  small  gall 
found  on  oak  leaves,  and  is  obtained  by 
i-  the  worker-ants  during  nocturnal  expedi- 
fooiis,  from  which  they  return  much  dis- 

v 

tended  ;  they  feed  such  workers  left  at 
home  as  may  be  hungry,  and  then  apparently  communicate  the 
remainder  of  the  sweet  stuff  they  have  brought  back  to  already 
partly  charged  ;'  honey-bearers "  left  in  the  nest.  The  details 
of  the  process  have  not  been  observed,  but  the  result  is  that  the 
abdomens  of  the  bearers  become  dis- 
tended to  an  enormous  extent  (Figs. 
62,  63),  and  the  creatures  move  but 
little,  and  remain  suspended  to  the 
roof  of  a  special  chamber.  It  is 
considered  by  M'Cook  that  these 
living  honey-tubs  preserve  the  fond 
till  a  time  when  it  is  required  for 
the  purposes  of  feeding  the  com- 
munity. The  distension  is  pro- 
duced entirely  by  the  overcharging 
of  the  honey-crop,  the  other  contents  of  the  abdomen  being 


FIG.  62.—  J/y /•-//.  * 

m ii nn.       Honey  -  pot     ant, 
dorsal  view. 


Flu.  63. — Mi/rmecocystus 
Lateral  view. 


iv  ANTS — CAMPONOTIDES  153 

forced  by  the  distention  to  the  posterior  part  of  the  body. 
Lubbock  has  since  described  an  Australian  ant,  Melophorus 
i njiatus,  having  a  similar  peculiar  habit,  but  belonging  to  the 
allied  tribe  Plagiolepisii.  Quite  recently  a  South  African  honey- 
tub  ant  belonging  to  the  distinct  genus  Plagiolepis  (Ptrimeni 
For.)  has  been  discovered,  affording  a  proof  that  an  extremely 
specialised  habit  may  arise  independently  of  relation  between  the 
Insects,  and  in  very  different  parts  of  the  world. 

Species  of  the  genus  Lasius  are  amongst  the  most  abundant 
of  the  ant-tribe  in  Britain.  They  are  remarkable  for  their  con- 
structive powers.  L.  niger,  the  common  little  black  garden-ant, 
forms  extensive  subterranean  galleries,  and  is  extremely  successful 
in  the  cultivation  of  various  forms  of  Aphidae,  from  the  products 
of  which  the  species  derives  a  large  part  of  its  subsistence.  The 
ants  even  transport  the  Aphidae  to  suitable  situations,  and  thus 
increase  their  stock  of  this  sugary  kind  of  cattle,  and  are  said  to 
take  the  eggs  into  their  own  dwellings  in  the  autumn  so  that 
these  minute  and  fragile  objects  may  be  kept  safe  from  the 
storms  and  rigours  of  winter.  These  little  creatures  are  brave, 
but  when  attacked  by  other  ants  they  defend  themselves  chiefly 
by  staying  in  their  extensive  subterranean  galleries,  and  blocking 
up  and  securing  these  against  their  assailants. 

Z.  fuliginosus,  another  of  our  British  species,  has  very  different 
habits,  preferring  old  trees  and  stumps  for  its  habitation  ;  in  the 
hollows  of  these  it  forms  dwellings  of  a  sort  of  card  ;  this  it 
makes  from  the  mixture  of  the  secretions  of  its  salivary  glands 
with  comminuted  fragments  of  wood,  after  the  fashion  of  wasps. 
It  is  a  moderate-sized  ant,  much  larger  than  the  little  L.  niger, 
and  is  of  a  black  colour  and  remarkably  shining ;  it  gives  off 
a  very  strong  but  by  no  means  disagreeable  odour,  and  may  be 
seen  on  the  hollow  trees  it  frequents,  stalking  about  in  large 
numbers  in  a  slow  and  aimless  manner  that  contrasts  strikingly 
with  the  active,  bustling  movements  of  so  many  of  its  congeners. 
When  this  species  finds  suitable  trees  near  one  another,  a  colony 
is  established  in  each  ;  the  number  of  individuals  thus  associated 
becomes  very  large,  and  as  the  different  colonies  keep  up  inter- 
communication,  this  habit  is  very  useful  for  purposes  of  defence. 
Forel  relates  that  he  once  brought  a  very  large  number  of 
Formica  pratensis  and  liberated  them  at  the  base  of  a  tree  in 
which  was  a  nest  of  L.  fuliginosus  ;  these  latter,  finding  them- 


154  HYMENOPTERA  CHAP. 

selves  thus  assaulted  and  besieged,  communicated  in  some  way, 
information  of  the  fact  to  the  neighbouring  colonies,  and  Forel 
soon  saw  large  columns  of  the  black  creatures  issuing  from  the 
trees  near  by  and  coming  with  their  measured  paces  to  the 
assistance  of  their  confreres,  so  that  the  invaders  were  soon  dis- 
comfited and  destroyed.  Although  the  European  and  North 
American  representatives  of  the  sub-family  Camponotides  live 
together  in  assemblies  comprising  as  a  rule  a  great  number  of 
individuals,  and  although  the  separate  nests  or  formicaries  which 
have  their  origin  from  the  natural  increase  of  a  single  original 
nest  keep  up  by  some  means  a  connection  between  the  members, 
and  so  form  a  colony  of  nests  whose  inhabitants  live  together  on 
amicable  terms,  yet  there  is  no  definite  information  as  to  how 
long  such  association  lasts,  as  to  what  is  the  nature  of  the  ties 
that  connect  the  members  of  the  different  nests,  nor  as  to  the 
means  by  which  the  colonies  become  dissociated.  It  is  known  that 
individual  nests  last  a  long  time.  Charles  Darwin  has  mentioned 
in  a  letter  to  Forel  that  an  old  man  of  eighty  told  him  he  had 
noticed  one  very  large  nest  of  Formica  n/fx  in  the  same  place 
ever  since  he  was  a  boy.  But  what  period  they  usually  endure 
is  not  known,  and  all  these  points  probably  vary  greatly  according 
to  the  species  concerned.  It  has  been  well  ascertained  that  when 
some  ants  find  their  nests,  for  some  unknown  reason,  to  be  unsuit- 
able the  inhabitants  leave  their  abodes,  carrying  with  them  their 
young  and  immature  forms,  and  being  accompanied  or  followed  by 
the  various  parasites  or  commensals  that  are  living  with  them. 
Wasmann  and  other  entomologists  have  observed  that  the  ants 
carry  bodily  some  of  their  favourite  beetle-companions,  as  well 
as  members  of  their  own  species.  Forel  observed  that  after 
a  nest  of  Formica  pratensis  had  been  separated  into  two  nests 
placed  at  a  considerable  distance  from  one  another  so  as  to  have 
no  intercommunication,  the  members  yet  recognised  one  another 
as  parts  of  the  same  family  after  the  lapse  of  more  than  a  month  ; 
but  another  observation  showed  that  after  some  years  of  separation 
they  were  no  longer  so  recognised. 

Although  it  is  now  well  ascertained  that  ants  are  able  to 
distinguish  the  individuals  belonging  to  their  own  nests  and 
colonies  from  those  that,  though  of  their  own  species,  are  not  so 
related  to  them,  yet  it  is  not  known  by  what  means  the  recogni- 
tion is  effected  ;  there  is,  however,  some  reason  to  suppose  that  it 


IV 


ANTS CAMPONOTIDES 


155 


is  by  something  of  the  nature  of  odour.  One  observer  has  noticed 
that  if  an  ant  fall  into  water  it  is  on  emerging  at  first  treated  as 
if  it  were  a  stranger  by  its  own  friends  ;  but  other  naturalists  have 
found  this  not  to  be  the  case  in  other  species.  Contact  with 
corrosive  sublimate  deprives  ants  for  a  time  of  this  power  of 
recognising  friends,  and  under  its  infhience  they  attack  one 
another  in  the  most  ferocious  manner. 

The  nests  and  colonies  of  the  species  of  Camponotides  we 
have  considered  are  all  constructed  by  societies  comprising  a 
great  number  of  indi- 
viduals ;  there  are, 
however,  in  the  tropics 
numerous  species  that 
form  their  nests  on 
foliage,  and  some  of 
these  contain  only  a 
few  individuals.  The 
leaf -nests  (Fig.  64)  of 
certain  species  of  Poly- 
/'//acltis  are  said  to  be 
formed  of  a  paper-like 
material,  and  to  con- 
tain each  a  female  and 
about  8  or  10  worker 
ants.  Forel :  has  ex- 
amined nests  of  several 
Indian  species,  and  finds  they  differ  from  those  of  other  ants  in 
consisting  of  a  single  cavity,  lined  with  silk  like  that  of  a  spider. 
These  nests  are  further  said  to  be  constructed  so  as  to  render 
them  either  inconspicuous  or  like  other  objects  on  the"  leaves  ; 
P.  argentea  covers  its  small  dwelling  with  little  bits  of  vegetable 
matter,  and  a  nest  of  P.  rastdla  was  placed  between  two  leaves 
in  such  a  manner  as  to  be  entirely  hidden.  All  the  species  of 
the  genus  do  not,  however,  share  these  habits,  P.  mayri  making 
a  card-nest,  like  Dolichoderus  and  some  other  ants.  The  species 
of  the  genus  Polyrhachis  are  numerous  in  the  tropics  of  the  Old 
World. 

Forbes  noticed  that   a   species  of  this  genus,  that  makes  its 
paper-like  nest  on  the  underside  of  bamboo-leaves  produces  a  noise 
1  Forel,  J.  Bombay  Soe.  viii.  1893,  p.  36. 


FIG.  64. — Nest  of  Polyrhachis  sp.     (After  Smith.) 


HYMENOPTERA 


CHAP. 


by  striking  the  leaf  with  its  head  in  a  series  of  spasmodic  taps. 
The  same  observer  has  recorded  a  still  more  interesting  fact  in 
the  case  of  another  species  of  this  genus — a  large  brown  ant- 
found  in  Sumatra.  The  individuals  were  "  spread  over  a  space, 
perhaps  a  couple  of  yards  in  diameter,  on  the  stem,  leaves,  and 
branches  of  a  great  tree  which  had  fallen,  and  not  within  sight 

of  each  other  ;  yet  the  tapping. was 
set  up  at  the  same  moment,  con- 
tinued exactly  the  same  space  of 
time,  and  stopped  at  the  same  in- 
stant ;  after  the  lapse  of  a  few 
seconds  all  recommenced  at  the 
same  instant.  The  interval  was 
always  of  about  the  same  duration, 
though  I  did  not  time  it ; 
each  ant  did  not,  however,  beat 
synchronously  with  every  other 
in  the  congeries  nearest  to  me  ; 
there  were  independent  tappings, 
so  that  a  sort  of  tune  was  played, 
each  congeries  dotting  out  its 
own  music,  yet  the  beginnings 
and  endings  of  the  musical  parties 
were  strictly  synchronous." 
Mr.  Peal  has  also  recorded  that  an  ant — the  name  is  not 
mentioned,  but  it  may  be  presumed  to  be  an  Assamese  species- 
makes  a  concerted  noise  loud  enough  to  be  heard  by  a  human 
being  at  twenty  or  thirty  feet  distance,  the  sound  being  produced 
by  each  ant  scraping  the  horny  apex  of  the  abdomen  three  times 
in  rapid  succession  on  the  dry,  crisp  leaves  of  which  the  nest  is 
usually  composed.  These  records  suggest  that  these  foliage-ants 
keep  up  a  connection  between  the  members  of  different  nests 
somewhat  after  the  same  fashion  as  do  so  many  of  the  terrestrial 
Camponotides.  Although  the  species  of  Cainponotides  have  no 
special  organ  for  the  production  of  sound  in  the  position  in  which 
one  is  found  in  Mvrmicides  and  Ponerides,  yet  it  is  probable  that 

v  >    t/  x 

they  are  able  to  produce  a  sound  by  rubbing  together  other  parts  . 
of  the  abdomen. 


FIG.  65. —  P<->h/,-/u:i-//i.i  JHI, nl  ii 
worker.      Singapore. 


IV 


ANTS 


157 


Sub-Fam.  2.  Dolichoderides. — Hind  //^/y  furnished  u-ith  lut 
one  constriction  so  that  only  a  single  scale  or  node  is  formed  ; 
tiling  rudiincntari/  ;  the  poison-sac  without  cushion. 

The  Dolichoderides  are  similar  to  Camponotides  in  appearance, 
and  are  distinguished  chiefly  by  the  structure  of  the  sting  and  the 
poison  apparatus.  To  this  we  may  add  that  Forel  also  considers 
the  gizzard  to  be  different  in  the  two  sub-families,  there  being  no 
visible  calyx  in  the  Dolichoderides,  while  this  part  is  largely 
developed  in  the  Camponotides.  This  is  one  of  the  least  extensive 
of  the  sub-families  of  ants,  not  more  than  150  species  being- 
yet  discovered.  Comparatively  little  is 
known  of  the  natural  history  of  its 
members,  only  a  very  small  number  of 
species  of  Dolichoderides  being  found  in 
Europe.  The  best  known  of  these  (and 
the  only  British  Dolichoderid)  is  Tapi- 
noma  erraticum,  a  little  ant  of  about  the 
size  of  Lasius  niger,  and  somewhat  similar 
in  appearance,  but  very  different  in  its 
habits.  T.  erraticum  does  not  cultivate 
or  appreciate  Aphides,  '  but  is  chiefly 
carnivorous  in  its  tastes.  Our  knowledge 
of  it  is  due  to  Forel,  who  has  noticed  that 
it  is  very  fond  of  attending  the  fights 
between  other  ants.  Here  it  plays  the 
part  of  an  interested  spectator,  and 
watching  its  opportunity  drags  off  the 
dead  body  of  one  of  the  combatants  in 
order  to  use  it  as  food.  Although  desti- 
tute of  all  power  of  stinging,  this  Insect 
has  a  very  useful  means  of  defence  FlG-  66-— fapinoma  en-ati- 

.  .        .  cum,      worker.       Britain. 

m    the    anal    glands    with    which    it    is        Upper  side  and  profile, 
provided  ;   these    secrete    a    fluid    having 

a  strong  characteristic  odour,  and  possessing  apparently  very 
noxious  qualities  when  applied  to  other  ants.  The  Tn/ii- 
noma  has  no  power  of  ejecting  the  fluid  to  a  distance,  but  is 
very  skilful  in  placing  this  odorous  matter  on  the  body  of  an 
opponent  by  touching  the  latter  with  the  tip  of  the  abdomen  ; 
on  this  being  done  its  adversary  is  usually  discomfited.  This 


i;8  HYMENOPTERA 


CHAP. 


Insect  is  subterranean  in  its  habits,  and  is  said  to  change  its 
abode  very  frequently.  T.  erraticum  occurs  somewhat  rarely  in 
Britain.  Forel  has  also  noted  the  habits  of  Liometopum  micro- 
cephalum,  another  small  European  species  of  Dolichoderides.  It 
is  a  tree-ant,  and  by  preference  adopts,  and  adapts  for  its  use,  the 
1  mrrows  made  by  wood-boring  beetles.  It  forms  extremely  populous 
colonies  which  may  extend  over  several  large  trees,  the  inhabitants 
keeping  up  intercommunication  by  means  of  numerous  workers. 
Xo  less  than  twelve  mighty  oaks  were  found  to  be  thus  united 
into  a  colony  of  this  ant  in  one  of  the  Bulgarian  forests.  The 
species  is  very  warlike,  and  compensates  for  the  extreme  minute- 
ness of  its  individuals  by  the  skilful  and  rapid  rushes  made  by 
combined  numbers  on  their  ant-foes  of  larger  size. 

Fritz  M tiller  has  given  a  brief  account,  under  the  name  of 
the  Imbauba  ant,  of  a  Brazilian- arboreal  ant,  that  forms  small 
nests  in  the  interior  of  plants.  The  species  referred  to  is  no 
doubt  an  Azteca,  and  either  A.  instabilis,  or  A.  mulleri.  The  nests 
are  founded  by  fertilised  females  which  may  frequently  be  found 
in  the  cells  on  young  Cecropia  plants.  Each  internode,  he  says, 
has  on  the  outside,  near  its  upper  part,  a  small  pit  where  the  wall 
is  much  thinner,  and  in  this  the  female  makes  a  hole  by  which 
she  enters.  Soon  afterwards  the  hole  is  completely  closed  by  a 
luxuriant  excrescence  from  its  margins,  and  it  remains  thus  closed 
until  about  a  dozen  workers  have  developed  from  the  eggs  of 
the  female,  when  the  hole  is  opened  anew  from  within  by  the 
workers.  It  is  said  that  many  of  the  larvae  of  these  ants  are 
devoured  by  the  grubs  of  a  parasite  of  the  family  Chalcididae. 
Tbis  Insect  is  thought  to  protect  the  plant  from  the  attacks  of 
leaf-cutting  ants  of  the  genus  Atfn. 

We  may  here  briefly  remark  that  much  has  been  written 
about  the  benefits  conferred  on  plants  by  the  protection  given  to 
them  in  various  ways  by  ants  :  but  there  is  reason  to  suppose 
that  a  critical  view  of  the  subject  will  not  support  the  idea  of 
the  association  being  of  supreme  importance  to  the  trees.1 

Sub-Fam.  2.  Myrmicides. — Pedicel  <>f  ahdomcn  formed  of  two 
in  11- marked  nodes  (knot-like  segments*).  Sting  present  (absent 
i a  Hie  Cryptocerini  and  Attini').  (It  should  be  noted  that  the 

1   See   von  Iliering,  Berlin,  cut.  Zcitschr.  xxxix.  1894,   p.  364  ;  and   Forel,  Ann. 
Soc.  cut.  /:.•/,/;,{//,•,  \\.  1896,  p.  170. 


IV 


ANTS MYRMTCIDES 


159 


workers  of  the  genera  Eciton  and  Aenictus  of  the  sub-family 
Dorylides  have,  like  the  Myrmicides,  tivo  nodes  in  the 


This  sub-family  consists  of  about  1000  species,  and  includes 
a  great  variety  of  forms,  but,  as  they  are 
most  of  them  of  small  size,  they  are  less 
known  than  the  Camponotides,  and  much 
less  attention  has  been  paid  to  their 
habits  and  intelligence.  Forel,  until  re- 
cently, adopted  four  groups  :  Myrmiciui, 
Attini,  Pseudomyrmini  and  Cryptocerini  ; 
but  he  is  now  disposed  to  increase  this 
number  to  eight.1  They  are  distinguished 
by  differences  in  the  clypeus,  and  in  the 
form  of  the  head  ;  but  it  must  be  noted 
that  the  characters  by  which  the  groups  , 

J  FIG.    6/.  —  Pheulologeton  labo- 

are    defined    are    not    in    all    cases    fully        riosus,    large    and    small 
applicable    to    the    males.      The    Crypto-        workers>    East  Iudia- 
cerini   are    in   external    structure    the   most    highly    modified    of 
Hymenoptera,  if  not  of  all  the  tribes  of  Insecta. 

i.   The  MYRMICINI  proper  are  defined  by  Forel  as  having  the 
antennae  inserted  near  the  middle,  a   little   behind   the   front,  of 

the  head,  which  has  carinae  on  the  inner 
sides,  but  none  on  the  outer  sides,  of  the 
insertions  of  the  antennae  ;  the  clypeus  ex- 
tends between  the  antennae. 

Certain  genera  of  small  European  ants  of 
the  group  Myrmicini  display  some  most 
anomalous  phenomena.  This  is  especially 
the  case  in  Formicoxenus,  Anergates  and 
Tomognathus.  The  facts  known  have,  how- 
ever, been  most  of  them  only  recently  dis- 
covered, and  some  obscurity  still  exists  as  to 
many  of  even  the  more  important  points 
iu  these  extraordinary  life-histories. 

it  has  long  lieen  known  that  the  little 
fonmcoxenus  mtiduius  lives  as  a  guest 
in  the  nests  of  Formica  rufa,  the  wood  -ant;  and  another 
similar  ant,  Xtenamma  westiuoodi,  which  shares  the  same  life, 


FIG.  68.—  Formicoxenus 
mtiduius,  male.  (After 

Adlerz.  ) 


Ann.  Soc.  cut.  Belgique,  xxxvii.  1893,  p.  163. 


i6o 


HVMENOPTERA 


CHAP. 


was  declared  by  Nylander  and  Smith  to  be  its  male ;  it  was 
however  shown  some  years  ago  by  Andre  that  this  is  a  mistake, 
and  that  S.  westwoodi  is  really  the  male  of  another  ant  that 
had  till  then  been  called  Asemorhoptrum  lippulinn.  This  correc- 
tion left  the  workers  and  females  of  Formicoxenus  nitidulus 
destitute  of  a  male,  but  Acllerz  has  recently  discovered  that  the 
male  of  this  species  is  wingless  and  similar  to  the  worker,  the 
female  being  a  winged  Insect  as  usual.  It  is  very  curious  that 
the  characters  by  which  the  male  is  distinguished  from  the 
worker  should  vary  in  this  species  ;  but  according  to  Adlerz  this 
is  the  case,  individuals  intermediate  in  several  points  between 
the  males  and  workers  having  been  discovered.  This  pheno- 
menon of  quite  wingless  males  in  species  where  the  female  is 
winged  is  most  exceptional,  and  is  extremely  rare  in  Insects  ;  but 
it  occurs,  as  we  shall  see,  in  one  or  two  other  Myrmicides.  Charles 

Darwin  made  the  very 
reasonable  suggestion 
that  winged  males  may 
be  developed  occasion- 
ally as  an  exceptional 
phenomenon,  and  it  is 
very  probable  that  this 
may  be  the  case,  though 
it  has  not  yet  been 
demonstrated.  Formi- 
coxenus nitidulus  occurs 
in  England  in  the  nests 
of  Formica  rufa  and  of 
F.  congerens,  but  we 
are  not  aware  that  the 
male  has  ever  been 

Fia.GQ.—Anergatesatratulus.  Europe.  A.  male,  with  found  ill  this  country, 
part  of  hind  leg  broken  off  ;  B,  female,  with  wings.:  C,  T,  „„..,„  Awernnt^  is 
female,  after  casting  the  wings  and  becoming  a  queen. 

allied  to  Formicoxenus, 

and  occurs  in  Central  Europe,  but  has  not  been  found  in  Britain ; 
the  female,  as  in  Formicoxenus,  is  winged  and  the  male  wingless, 
but  there  is  no  worker-caste  ;  the  male  is  a  rather  helpless  creature, 
and  incapable  of  leaving  the  nest.  The  species  lives  in  company 
with  Tetru'inoritnn  cawjtitintt,  a  little  ant  very  like  M//n/t!c</,  and  not 
uncommon  in  South-East  England.  The  female  Anergates  is  at 


I 


IV 


M  VRMICIDES ANERGA  TES  I  6  I 


first  an  active  little  creature  with  wings,  but  after  these  are  lost 
the  body  of  the  Insect  becomes  extremely  distended  as  shown  in 
Fig.  69,  C;  the  creature  is  in  this  state  entirely  helpless,  and  as 
there  are  no  workers,  the  Anergates,  is  completely  dependent,  for 
the  existence  of  itself  and  its  larvae,  on  the  friendly  offices  of  the 
Tetramorium  that  lives  with  it.  The  mode  of  the  association 
of  these  two  Insects  is  at  present  both  unparalleled  and  inexplic- 
able, for  only  workers  of  the  Tetramorium  are  found  in  company 
with  the  £  and  5  Anergates ;  the  community,  in  fact,  consisting 
of  males  and  females  of  one  species  and  workers  of  another.  The 
nests  of  Anergates  are  so  rare  that  only  a  few  naturalists  have 
been  able  to  observe  them  (Schenk,  von  Hagens,  and  Forel  may 
be  specially  mentioned),  but  in  the  spots  where  they  occur, 
nests  of  the  Tetramorium,  containing  all  the  forms  of  that  species, 
are  numerous,  and  it  therefore  seems  probable  that  a  young  fertile 
female  of  the  Anergates  may  leave  a  nest  in  which  it  was  born, 
enter  a  nest  of  the  Tetramorium,  and,  destroying  the  queen  thereof, 
substitute  herself  in  the  place  of  the  victim  ;  but  if  this  be  really 
the  case,  the  larvae  and  pupae  of  the  Tetramorium  must  also  be 
destroyed,  for  no  young  of  the  Tetramorium  are  ever  found  in 
these  strange  associations.  It  is  very  difficult  to  believe  that 
the  Tetramorium  workers  should  be  willing  to  accept  as  their 
queen  a  creature  that  commenced  her  acquaintance  with  them  by 
destroying  their  own  queen  or  queens  and  a  number  of  their 
young  sisters  ;  especially  as  the  Tetramorium  is  a  more  powerful 
ant  than  the  Anergates,  and  could  readily  dispose  of  the  murderous 
intruder  if  it  were  disposed  to  do  so.  It  is  known,  however, 
that  colonies  of  Tetramorium  completely  destitute  of  queens  some- 
times occur,  and  Wasmann  has  suggested  that  the  female  Aner- 
gates may  seek  out  one  of  these,  and  installing  herself  therein  as 
a  substitute,  may  be  accepted  by  the  orphaned  colony.  This 
plausible  hypothesis  has  still  to  be  verified. 

The  genus  Cardiocondyla  also  exhibits  the  phenomenon  of 
apterous,  worker-like  males,  while  in  one  species,  C.  emeryi,  a 
winged  male  is  also  known  to  exist. 

Tomognathus  sublaevis  is  a  little  Myrmicid  ant,  found  rarely 
in  Denmark  and  Sweden,  where  its  habits  have  recently  been 
studied  by  Adlerz.  A  band  of  the  Tomognathus  attack  the  nest 
of  another  little  Myrmicid,  Leptothorax  acervorv.  m ,  and  succeed 
by  their  own  pertinacity  and  the  fears  of  the  Leptothorax  in 

VOL.  VI  M 


1 62  HYMENOPTERA 


CHAP. 


obtaining  possession  of  it ;  the  legitimate  owners  disappear,  leav- 
ing the  Tomognathus  in  possession  of  their  larvae  and  pupae ; 
these  complete  their  development  only  to  find  themselves  the 
slaves  of  Tomognathus.  The  subsequent  relations  of  the  two 
ants  are  friendly,  the  slaves  even  preventing  their  masters  from 
wandering  from  the  nest  when  they  wish  to  do  so.  If  an  estab- 
lished mixed  community  of  this  nature  is  in  want  of  additional 
servitors,  the  Tomognatlius  secure  a  supply  by  raids  after  the 
fashion  of  the  Amazon-ant,  bringing  back  to  their  abode  larvae 
and  pupae  of  Leptothoraoc  to  be  developed  as  slaves.  It  was  for- 
merly supposed  that  the  Tomognathus  continued  its  species  by 
perpetual  parthenogenesis  of  the  workers,  for  neither  males  nor 
females  could  be  found.  Adlerz  l  has,  however,  now  discovered  the 
sexual  individuals.  The  male  is  an  ordinary  winged  ant,  and  is 
so  like  that  sex  of  the  Lcptoilwrax,  that  Adlerz  had  failed  to 
distinguish  the  two  before  he  reared  them.  The  females  are 
apterous,  and  in  fact  like  the  workers.  It  would  perhaps  be 
more  correct  to  say  that  the  workers  of  this  species  vary  greatly 
but  never  become  winged  ;  some  of  them  have  ocelli  and  a  struc- 
ture of  the  thorax  more  or  less  similar  to  that  of  winged  females, 
though  none  have  been  found  with  wings.  Certain  of  these 
females  possess  a  receptaculum  seminis,  and  Adlerz  treats  this  as 
the  true  distinction  between  female  and  worker.  In  accordance 
with  this  view  the  female  of  Tomognatli  us  may  be  described  as  a 
worker -like  individual  possessing  a  receptaculum  seminis,  and 
having  more  or  less  of  the  external  structures  of  winged  females, 
though  never  being  actually  winged.  It  is  probable  that  other 
workers  reproduce  parthenogenetically.  The  males  of  this  species 
will  not  unite  with  females  from  the  same  nest,  thus  differing 
from  many  other  ants,  in  which  union  between  individuals  of  the 
same  nest  is  the  rule.  Finally,  to  complete  this  curious  history, 
we  should  remark  that  the  larvae  of  the  Tomot/nathus  are  so 
similar  to  those  of  the  Leptothorax  that  Adlerz  is  quite  unable  to 
distinguish  the  two. 

Stronyylognatlius  testaceusand  S.  kuhcri  live  in  association  with 
Tetramorium  caespit-um,  and  are  cared  for  by  these  latter  ants;  it 
is  notable  that  as  in  the  case  of  the  slave-making  Polyergus 
rufescens  the  mandibles  of  the  Strongylognathus  are  cylindrical 
and  pointed,  and  I  her* 'tore  unsuitable  for  industrial  occupations. 

1  Jiili.  Hvenska  Ale.  x.\i.  1896,  Afd.  iv.  Xo.  -1. 


iv  ANTS MYRMICIDES  163 

S.  testaceus  is  a  weak  little  ant,  and  lives  in  small  numbers  in  the 
nests  with  T.  caespitum,  which  it  is  said  to  greatly  resemble  in 
appearance.  The  proportions  of  the  forms  of  the  two  species 
usually  associated  is  peculiar,  there  being  a  great  many  workers 
of  T.  caespitum  both  in  the  perfect  and  pupal  states,  and  also  all 
the  sexes  of  the  Strongylognathus,  of  which,  however,  only  a  few 
are  workers.  This  would  seem  to  suggest  that  S.  testaceus  attacks 
and  pillages  the  nests  of  T.  caespitum  in  order  to  carry  off  worker 
pupae,  just  as  Polyergus  ru/escens  does.  But  the  facts  that  S. 
testaceus  is  a  weaker  Insect  than  the  Tetramorium,  and  that  only 
a  few  of  its  worker-caste  are  present  in  a  community  where  there 
are  many  workers  of  the  Tetramorium,  seem  to  negative  the  view 
that  the  latter  were  captured  by  the  former ;  and  the  mode  in 
which  the  associated  communities  of  these  two  species  are  started 
and  kept  up  is  still  therefore  in  need  of  explanation. 

Strongylognathus  huberi  is  a  much  stronger  Insect  than  its 
congener,  S.  testaceus,  and  Forel  has  witnessed  its  attack  on 
T/'framorium  caespitum.  Here  the  raid  is  made  in  a  similar 
manner  to  that  of  Polyergus  ru/escens  on  Formica ;  the  Tctramo- 
r in  in  is  attacked,  and  its  pupae  carried  off  to  the  abode  of  the 
Strongylognathus  to  serve  in  due  time  as  its  slaves.  The  man- 
dibles of  S.  huberi,  being  similar  in  form  to  those  of  Polyergus 
ru/escens,  are  used  in  a  similar  manner. 

Although  T.  caespitum  is  common  enough  in  South-East  Eng- 
land, it  is  to  be  regretted  that  none  of  the  guests  or  associates  we 
have  mentioned  in  connection  with  it  occur  in  this  country.  It 
is  a  most  variable  species,  and  is  distributed  over  a  large  part  of 
the  globe. 

Our  British  species  of  Myrmicides,  about  ten  in  number, 
all  belong  to  the  group  Myrmicini ;  none  of  them  are  generally 
common  except  Murmica  rubra,  which  is  a  most  abundant  Insect, 
and  forms  numerous  races  that  have  been  considered  by  some 
entomologists  to  be  distinct  species ;  the  two  most  abundant  of 
these  races  are  M.  ruginodis  and  M.  scabrinodis,  which  sometimes, 
•at  the  time  of  the  appearance  of  the  winged  individuals,  form  vast 
swarms. 

The  tiny  Mb-nomorium  pharaonis  is  a  species  that  has 
been  introduced  into  Britain,  but  now  occurs  in  houses  in 
certain  towns ;  it  sometimes  accumulates  on  provisions  in  such 
numbers  as  to  be  a  serious  nuisance.  Seventeen  thousand 


164 


HYMENOPTERA 


CHAP. 


individuals   weigh    1    gramme,  and   it    is    probable    that    a    nest 

may  include  millions  of  specimens. 

The  genus  Aphaenogaster^  and  its  immediate-  allies  include  the 

harvesting  ants  of  Europe  and  North  America  :  they  form  subter- 

ranean nests  consisting  of  iso- 
lated chambers  connected  by 
galleries  ;  some  of  the  chambers 
are  used  as  store  -houses  or 
granaries,  considerable  quantities 
of  corn,  grass,  and  other  seeds 
being  placed  in  them.  A. 
structor  and  A.  lar/i/i/'//*  have 
been  observed  to  do  this  in 
Southern  Europe  by  Lespes, 
Moggridge,  and  others. 

In  the  deserts  about  Algeria 
and  Tunis  a  harvesting  ant, 
Aphaenogaster  (Messor)  aren- 
arius,  is  an  important  creature  : 
its  subterranean  dwellings  are 
very  extensive,  and  are  placed 
at  a  depth  of  several  feet  from 
the  surface.  Entrance  to  these 
dwellings  is  obtained  by  small 

holes,  which  are  the   orifices   of 
Flu.  70.  —  Aphaenogaster  (Messor)  barbarus.         ,  ,  „  , 

Algeria.    A,  male  ;  B,  winged  female  :   galleries  many  feet    in    length  : 


C,   large  worker   or  soldier;    D,   small 
worker,      x  -I}. 


the      holes     are      SUlTOimded      by 

.        . 

pellets  ot  sand  projecting  some- 
what above  the  general  surface,  and  consequently  making  the 
places  conspicuous.  The  subterranean  works  occupy  an  area  of 
iifty  or  a  hundred  square  yards  excavated  at  a  depth  of  three  to 
six  feet.  In  these  immense  nests  there  exists  a  form  of  worker, 
of  very  small  size,  that  never  conies  to  the  surface.2 

Pogonomyrmex  l><irl><itns  and  other  species  have  been  observed 
to  do  harvesting  in  North  America.  After  the  workers  of  P. 
!>/  1,  -I  in  Ins  have  taken  the  seeds  into  the  nest  they  separate  the 
husks  and  carry  them  out,  depositing  them  on  a  heap  or  kitchen- 

1  Until  I'crcully  this  genus  was  generally  known  as  Atta,  but  this  name  is  now 
applied  to  the  leai'-futting  ants,  that  were  formerly  called  Oeeodoma. 

2  Foivl,  /;,///.  Soc.   Vaudoise,  xxx.  pp.  29-30,  1S91. 


IV 


ANTS MYRMICIDES  165 


midden,  formed  near  by.  M'Cook  has  witnessed  and  described 
the  process  of  stripping  the  seeds. 

Certain  genera — e.g.  Aphaenogaster,  Plieidole — exhibit  great 
disparity  in  the  forms  of  the  workers,  some  of  which  are  of 
size  much  superior  to  the  others,  and  possess  disproportionately 
large  heads ;  these  large  individuals  are  found  in  the  same  nest 
as  the  smaller  forms.  All  the  intermediate  forms  may  frequently 
be  found,  and  at  the  same  time,  in  the  genus  Apliaenogaster ;  but 
in  Pheidole  intermediates  are  of  the  utmost  rarity. 

The  genus  Cremastogaster  is  remarkable  on  account  of  the 
shape  of  the  hind  body  and  its  articulation,  which  give  the 
abdomen  the  appearance  of  being  put  on  upside  down.  This 
mode  of  articulation  may  allow  the  Insect  to  threaten  its  enemies 


X 

A  B 

Fio.  71.' — Oremastogaster  tricolor,  worker.     A,  with  abdomen  extended  ;  B,  uplifted. 

when   they  are  in  front   of  it ;  but  it   is   doubtful  whether   the 
Cremastogaster  possesses  an  effective  sting. 

ii.  The  group  ATTINI  is  distinguished  by  the  presence  of  a 
carina  near  the  eye,  by  the  antennae  being  inserted  at  a  moderate 
distance  from  one  another,  by  the  clypeus  being  prolonged  back- 
wards between  them ;  and  by  the  absence  of  a  sting.  The 
group  is  not  represented  in  Europe,  but  in  Tropical  America  the 
ants  belonging  to  it  are  amongst  the  most  important  of  natural 
objects.  The  species  of  the  genus  Atta  (usually  styled  Oecodomct) 
are  the  formidable  leaf-cutting  ants  of  America.  They  occur  in 
enormous  colonies  in  certain  places,  and  will  in  a  short  time 
completely  strip  a  tree  of  its  leaves.  As  they  appear  to  prefer 
trees  of  a  useful  kind,  especially  those  planted  by  man,  their 
ravages  are  often  of  the  most  serious  nature.  The  natives, 
feeling  it  hopeless  to  contend  with  these  Insect  hordes,  only  too 
frequently  abandon  all  attempts  to  cultivate  the  trees  and 
vegetables  the  Insects  are  fond  of.  Both  Bates  and  Belt  have 


1 66  HYMENOPTERA 


CHAP. 


given  accounts  of  some  points  in  the  economy  of  these  ants. 
They  are  amongst  the  largest  of  the  Formicidae,  the  females  in 
some  cases  measuring  about  two  and  a  half  inches  across  their 
expanded  wings  ;  the  males  are  much  smaller,  but  are  less  dis- 
similar to  their  partners  than  is  usual  among  ants.  The  workers, 
on  the  other  hand,  are  so  extremely  different,  that  no  one  would 
suppose  them  to  he  at  all  related  to  the  males  and  females  (see 
vol.  v.  Fig.  339). 

The  mode  of  operation  of  these  ants  is  to  form  paths  from 
their  formicary  extending  for  a  considerable  distance  in  various 
directions,  so  that  they  have  a  ready  access  to  any  spot  in  a 
district  of  considerable  extent ;  when  a  tree  or  bush  is  found 
bearing  leaves  suitable  for  their  purposes,  the  worker  ants  ascend 
it  in  large  numbers  and  cut  up  the  leaves  by  biting  out  of  them 
pieces  similar  in  size  and  shape  to  a  small  coin ;  these  pieces  are 
then  carried  back  in  the  jaws  of  the  ants  to  their  nests ;  the  ant- 
paths  are  therefore  constantly  traversed  by  bands  of  little  creatures 
carrying  burdens  homewards,  or  hurrying  outwards  in  search  of 
suitable  trees. 

The  formicaries  are  of  considerable  size,  and  are  described 
as  consisting  of  low  mounds  of  bare  earth  of  considerable  extent. 
Bates  speaks  of  as  great  a  circumference  as  forty  yards  ;  these 
accumulations  of  earth  have  frequently  an  appearance  different 
from  the  adjoining  soil,  owing  to  their  being  formed  of  subsoil 
brought  up  from  below ;  they  are  kept  bare  by  the  ants  con- 
stantly bringing  to  and  depositing  on  the  surface  fresh  material 
resulting  from  their  subterranean  excavations.  The  true  abodes, 
beneath  the  earth,  are  of  greater  extent  than  the  mounds  them- 
selves, and  extend  to  a  considerable  depth ;  they  consist  of 
chambers  connected  by  galleries. 

The  leaf -cutting  ants  extend  their  range  to  North 
America,  and  M'Cook  has  recently  called  attention  to  a  case 
there  in  which  A.  fen-ens  made  an  underground  route  at  an 
average  depth  of  18  inches,  and  at  an  occasional  depth  oT  0 
feet,  extending  448  feet  entirely  beneath  the  earth,  after  which 
it  was  continued  for  185  feet  to  reach  a  tree  which  the  ants  were 
engaged  in  defoliating.  This  route, extending  altogether  to  a  length 
of  more  than  GOO  feet,  presented  only  a  very  slight  deviation 
from  a  straight  line  drawn  between  the  point  of  departure  and 
the  object  to  be  attained.  By  what  sense  this  ant  was  enabled 


IV 


MYRMICIDES LEAF-CUTTING  ANTS  I  6/ 


to  make  a  subterranean  tunnel  in  a  straight  line  to  a  desired 
object  situated  at  so  great  a  distance,  we  know  not. 

The  use  the  leaf-cutting  ants  make  of  the  enormous  amount 
of  material  they  gather  was  for  long  a  subject  of  debate,  and  has 
only  recently  been  ascertained  by  the  observations  of  Moller. 
After  being  carried  to  the  nest  the  pieces  of  leaves  are  cut  into 
small  fragments  by  another  set  of  workers  and  formed  into  balls, 
which  are  packed  in  various  parts  of  the  nest,  and  amongst 
which  the  mycelium  of  a  fungus — Rozites  gongylophora — -ramifies. 
This  fungus  the  ants  cultivate  in  the  most  skilful  manner : 
they  manage  to  keep  it  clear  from  mouldiness  and  bacterial 
agents,  and  to  make  it  produce  a  modified  form  of  growth  in 
the  shape  of  little  white  masses,  each  one  formed  by  an  agglomera- 
tion of  swellings  of  the  mycelium.  These  form  the  chief  food  of 
the  colony.  Moller  ascertained  by  experiment  that  the  results 
were  due  to  a  true  cultivation  on  the  part  of  the  ants :  when 
they  were  taken  away  from  the  nests,  the  mycelium  produced 
two  kinds  of  conidia  instead  of  the  ant-food. 

Many  details  of  the  economy  of  these  leaf-cutting  ants  are 
still  very  imperfectly  known.  The  large-headed  forms,  called 
soldiers,  have  been  the  subject  of  contradictory  statements ; 
Bates  having  concluded  from  his  own  observations  that  they 
are  harmless,  while  Mr.  J.  H.  Hart  assures  us  that  they  are  very 
fierce  and  vindictive,  and  inflict  very  serious  wounds  by  biting 
(the  Attini  do  not  sting).  We  anticipate  that  the  observations 
of  both  these  naturalists  will  prove  to  be  substantially  correct, 
and  that  the  differences  in  habits  will  be  found  to  be  owing  to 
distinctions  in  the  conditions  of  the  community.  In  connection 
with  this  point  we  may  remark  that  the  function  of  the  ex- 
cessively large  heads  of  certain  kinds  of  soldier-ants  is  still 
obscure.  In  the  East  Indian  Pheidologeton  diversus  the  big- 
soldiers  are  quite  one  hundred  times  as  large  as  the  smaller 
workers.  As  these  latter  bite  viciously  it  would  naturally  be 
supposed  that  their  gigantic  confreres  with  enormous  heads  would 
be  warriors  of  a  most  formidable  nature  ;  but,  as  a  matter  of  fact, 
the  giants  are  unable  to  bite  even  when  they  try  to  do  so. 
Aitken  has  somewhere  suggested  that  these  enormous  individuals 
play  the  part  of  state  elephants ;  and  we  have  been  informed  by 
Colonel  Bingham  that  the  small  ants  may  frequently  be  seen 
riding  in  numbers  on  their  unwieldy  fellows.  We  anticipate 


1 68  HYMENOPTERA  CHAP. 

however,  that  some  other  function  will  be  found  to  exist  for 
these  forms  with  enormous  heads.  An  examination  of  their 
organs  of  sense  and  of  voice  is  very  desirable. 

Details  of  the  modes  in  which  the  great  communities  of  the 
leaf- cutting  Attidae  are  maintained,  are  still  wanting.  The 
females  do  not,  we  have  been  informed  by  Mr.  Hart,  possess 
any  considerable  powers  of  aftergrowth,  so  that  there  is  no  reason 
to  suppose  them  to  be  unusually  prolific.  At  certain  seasons 
great  swarms  of  winged  individuals  are  produced,  and  after 
leaving  the  nests  pair  in  the  manner  of  our  European  Myrmica. 
Possibly  the  females  may,  after  losing  their  wings,  again  enter 
the  large  communities.  Yon  Ihering  states  that  the  workers  of 

o  o 

Atta  lundi  are  fertile. 

iii.  The  group  PSEUDOMYRMIXI  includes  the  genera  Pscudo- 
ini/riiia  and  Himn,  which  are  by  some  entomologists  treated  as 
but  a  single  genus.  The  antennae  are  inserted  near  together  on  the 
front  of  the  head  ;  there  is  no  carina  on  the  head  external  to 
their  insertion,  and  the  clypeus  does  not  extend  forwards  between 
them.  The  Insects  are  usually  of  elongate  form,  possess  a  sting, 
and  have  a  naked  pupa.  The  group  occurs  in  both  hemispheres, 
but  is  exclusively  exotic,  and  but  little  is  known  of  the  habits  of 
its  members.  Forel  has  recently  observed  that  numerous  species 
live  inside  dried  stems  of  grass  or  in  hollow  twigs,  and  are 
beautifully  adapted  for  this  mode  of  life  by  their  elongate  form, 
some  of  them  being  as  slender  as  needles.  Some  interesting 
observations  have  been  made  in  Nicaragua  by  Belt  on  Pscudo- 
mynna  bicolor  and  its  relations  with  an  acacia-tree,  in  the  thorns 
of  which  it  lives.  The  acacia  in  question  is  called  the  bull's-horn 
thorn,  because  the  branches  and  trunk  are  armed  with  strong 
curved  spines,  set  in  pairs,  and  much  resembling  the  horns  of 
the  quadruped  whose  name  they  bear.  The  ant  takes  possession 
of  a  thorn  by  boring  a  small  hole  near  the  distal  extremity,  and 
forms  its  nest  inside.  The  leaves  of  this  plant  are  provided 
with  glands  that  secrete  a  honey-like  fluid,  which  it  appears 
forms  the  chief,  if  not  the  sole,  subsistence  of  the  ant.  I'.elt 
considers  that  the  presence  of  the  ant  is  beneficial  to  the  acacia  ; 
he  supposes  that  the  ants  assume  the  rights  of  proprietors,  and  will 
not  allow  caterpillars  or  leaf-cutting  ants  to  meddle  with  their 
property ;  the  leaves  are,  he  thinks,  so  preserved  to  the  benefit 
of  the  tree. 


IV 


ANTS MYRMICIDES 


169 


Kothney  has  given   some   particulars   of  the   habits   of  Sima 
rufo-nigra,  an  ant  of  this  group  that  appears  to  be  not  uncommon 


FIG.  72. — Sima  rufo-nigra  and 
its  associates.  A,  winged 
female  ;  B,  worker,  of  the 
ant ;  C,  Kliinoijsis  ruji- 
cornis,  a  fossorial  wasp  of 
the  sub-family  AmjinH- 
cicles  ;  D,  a  spider,  Salticus 
sp.  The  coloration  is  ex- 
tremely similar  in  all  these 
creatures. 


near  Calcutta,  where  it  lives  on  the  trunks  of  trees  in  company 
with  a  spider  and  a  wasp  that  greatly  resemble  it  in  form  and 
in  colour.  The  three  creatures  seem  to  associate  together 
on  amicable  terms ;  indeed  the  wasp  and  the  ant  occasionally 
indulge  in  wrestling  matches  without  doing 
one  another  any  serious  harm.  In  connection 
with  this  fact  we  may  observe  that  other 
species  of  ants  have  been  observed  to  indulge 
in  sports  and  feats  of  agility. 

S.  leviceps,  an  Australian  species  of  this 
genus,  is  furnished  with  a  stridulating  file 
that  has  the  appearance  of  being  constructed 

so  as   to  produce   two  very  different  kinds  of  Fit;.  73.— stridulating  file 
j  of  Sima  lerlceps. 

iv.  The  CRYPTOCERINI  are  distinguished  from  other  ants  by  their 
antennae  being  inserted  at  the  sides  of  the  head,  where  they  are 
placed  between  ridges  or  in  a  groove  into  which  they  can  be 
withdrawn  ;  when  in  some  cases  they  are  entirely  concealed. 
These  ants  assume  a  great  variety  of  shapes  and  forms,  some  of  which 
look  almost  as  if  they  were  the  results  of  an  extravagant  imagin- 
ation. The  skeleton  is  usually  much  harder  than  it  is  in  other 


170  HYMENOPTERA  CHAP. 

ants  ;  the  abdomen  consists  almost  entirely  of  one  very  large  seg- 
ment, there  being,  however,  three  others  visible  at  its  extremity  ; 
these  segments  can  be  only  slightly  protruded,  and  the  ants  have 
110  power  of  stinging.  They  are  probably  most  of  them  arboreal 
in  their  habits.  Nearly  all  of  the  known  forms  are  exotic. 
According  to  the  observations  of  Bates  the  species  of  the  genus 

Cryptocerus  in  the  Amazons  Valley 
may  frequently  be  observed  in  dry 
open  places  on  low  trees  and  1  tushes, 
or  running  on  branches  of  newly  felled 
trees  ;  they  also  visit  flowers  abund- 
antly. The  species  generally  are 
wood-borers,  usually  perforating  the 
dead  branches  of  trees.  C.  atmttis  has 
been  observed  to  construct  its  nests 
in  the  dead,  suspended  branches  of 
woody  climbers  :  a  number  of  neatly 
drilled  holes  are  all  that  can  he  seen 
pressed  first  joint  of  the  haul  externally  ;  but,  inside,  the  wood  is 

foot    is    shown   at  a    and  b  in    P       -,  c  •,-, 

different  positions.  freelj  perforated   with   intercommuni- 

cating    galleries.       Each     community 

appears  to  consist  of  a  single  female  and  two  kinds  of  workers  ; 
the  latter  in  some  species  are  quite  unlike  each  other,  differing 
in  the  form  of  the  head,  and  in  the  armature  of  the  thorax  and 
nodes  of  the  peduncle.  The  species  of  Cryj>t<«-fi'nx  appear  to  be 
omnivorous,  and  are  frequently  attracted  by  the  excrement  of  birds. 
The  pupae  are  not  enclosed  in  a  cocoon.  In  the  South  of  Europe 
two  very  minute  ants,  of  the  genera  /S'/v////////o///.s  and  k'jri.tritus, 
belonging  to  this  family,  are  met  with  under  very  large  stones 
partly  embedded  in  the  earth.  They  are  of  the  greatest  rarity. 

Sub-fam.  4.  Ponerides.  --Hind  body  elongate,furnished  i'-itJi  one 
node  at  the  base,  «n<l  li«ri  n</  <ih<>  i/i-ntt  fnjmriti/  <//'  •inurement 
between  the  first  «nd  second  segments,  bct/'-t^'/i  •<>•//  ir/i  there  is 
a  .s7  //////  constriction,  Rtin<j  wrl! 


This  suit-family  includes  numerous  genera  and  about  400 
species.  The  Ponerides  have  an  elongate  hind-body;  the  second 
segment  behind  the  node  is  eapable  of  great  movement  in  and  out 
of  the  preceding  segment,  and  for  this  purpose  is  furnished  with 
a  basal  portion  slightly  more  slender  than  the  apical  part;  this 


iv  ANTS — PONERIDES  17  I 


basal  part  is  usually  concealed  within  the  more  anterior  segment, 
the  hind  margin  of  which  embraces  it  very  closely.  On  the 
middle  of  the  dorsal  aspect  of  this  articulation  there  is  usually 
placed  a  stridulating  organ,  consisting  of  an  elongate  band  or 
patch  of  very  fine  lines  ;  this  gives  out  a  sound  when  the  second 
segment  is  moved  in  and  out  of  the  first  at  a  time  when  the 
posterior  edge  of  the  latter  is  slightly  depressed. 

We  follow  Forel  in  including  the  Australian  bull-dog  ants— 
Mynnecia — in  Ponerides,  as  well  as  the  Odontomachi.  The 
former  have,  however,  a  definite  pedicel,  consisting  of  two  nodes 
(Fig.  76).  In  the  Odontomachi  the  mandibles  are  approximate 
at  their  bases,  being  inserted  on  the  middle  of  the  front  of  the 
head  (Fig.  77). 

This  sub-family  includes  a  considerable  number  of  species, 
and  is  found  in  all  parts  of  the  world.  Extremely  little  is 
known  as  to  the  habits,  but  the  true  Ponerides  do  not,  so 
far  as  is  known,  occur  in  large  communities,  and  it  seems 
probable  that  they  are  destitute  of  the  powers  of  combined 
action  that  are  so  remarkable  in  the  Camponotides,  and  in  some 
of  the  Myrmicides  and  Dorylides.  Most  of  the  species  that 
have  been  described  are  known  by  only  one  sex,  so  that  very 
little  knowledge  exists  as  to  the  sexual  distinctions  ;  but  from 
the  little  that  is  kno\vn  it  would  appear  that  the  three  sexual 
forms  are  not  so  differentiated  as  they  are  in  most  of  the  Cam- 
pouotides  and  Myrmicides. 

The  species  of  the  genus  Leptoyenys  are  believed  by  Emery 
and  Forel  to  possess  an 
apterous  female.  Mr. 
Perkins  has  observed  that 
the  Hawaiian  L.falciyera 
has  workers  with  differ- 
ent kinds  of  sting,  but 
no  true  female.  Males  of 
this  species  are,  however, 
abundant.  "\Vroughton 
has  recently  discovered 
that  one  member  of  this 

„       m  .,  FIG.  75. — 1)11111/11,11, 'I'll  </rtiu<lix,  worker.      Amazons. 

genus     is     of     Termito- 

phagous  habits,  but  this  is  not  the  case  with  L.fulcigera.      Dino- 

ponera  grandis  (Fig.    75)   is    the   largest    of   the    Ponerides,   its 


1/2  HYMENOPTERA  CHAP. 

workers  attaining  an  inch  and  a  quarter  in  length.  This  Insect, 
according  to  Bates,  marches  in  single  file  in  the  thickets  at  Para  ; 
its  colonies  consist  of  a  small  number  of  individuals,  and  are 
established  at  the  roots  of  slender  trees.  The  effects  of  its 
powerful  sting  are  not  so  serious  as  is  the  case  with  some  of  the 
smaller  ants. 

In  Britain  we  have  only  two  representatives  of  the  sub-family, 
viz.  Ponera  contracta,  a  small  ant  of  dirty-yellow  colour,  found 
rarely  in  the  Southern  counties,  living  in  moss  or  under  stones. 
Its  colonies  consist  of  only  a  few  individuals  ;  Forel  giving  fifty 
as  the  highest  number  he  has  observed.  The  second  species,  P. 
pwnctatissima,  presents  the  almost  unique  peculiarity  of  possess- 
ing two  forms  of  the  male  sex,  one  of  them  resembling  the 
worker  in  most  of  its  peculiarities,  and  in  being  destitute  of 
wings,  while  the  other  is  winged,  as  is  usual  in  male  ants.  In 
the  island  of  St.  Vincent  another  species  of  Ponera  has  been  dis- 
covered having  an  apterous  and  worker-like  male,  and  was  named 
by  Forel  P.  t'l'f/nfifiidria.1  The  discovery  of  this  form  has  led 
him  to  express  some  doubt  as  to  whether  Ponera  pu  nchiti^i  nm 
has  two  forms  of  males ;  but  it  seems  probable  that  it  really  is 
so,  the  ergatoid  males  being  produced  under  somewhat  different 
circumstances  from  the  normal  males.  We  have  already  said 
that  Ci'ti'diocnittfi/la  and  a  few  other  Myrmicides  exhibit  an 
analogous  peculiarity. 

The  genus  Myrmccia  is  confined  to  the  Australian  continent 
;nul  Tasmania,  and  includes  a  considerable  number  of  species  of 
large  and  moderate-sized  ants,  the  classification  of  which  has 
been  a  subject  of  difference  of  opinion-.  This  has  arisen  from 
the  fact  that  the  nodes  of  the  abdominal  pedicel  are  more  similar 
to  those  existing  in  the  Myrmicides  than  to  those  of  the  typical 
Ponerides.  There  are,  however,  some  American  members  of  the 
latter  sub-family  (Para /m in  /•»  <-l«r<it«,  <v/.)  that  differ  but  little 
in  this  point  from  J///v///.r/^,  and,  moreover,  the  pupae  of  Jfyr- 
mecia  are  enclosed  in  a  cocoon,  while  in  the  Myrmicides  they 
are  usually  naked.  On  the  other  hand  the  nests  are,  it  appears, 
very  large  and  populous,  more  like  what  exists  in  the  Myrmi- 
cides ;  there  is  no  true  stridulating  organ  on  the  first  abdominal 
segment.  The  genus  is  therefore  one  of  those  interesting 
anomalies  that  form  so  large  a  proportion  of  the  Australian 

1    Tr.  ent.  Soc.  l.nn,],,ii.  is;i:;,  j.j..  :i6"i-467. 


iv  PONERIDES  —  BULL-DOG  ANTS  173 

fauna,  and  will  probably  be  ultimately  treated  as  a   distinct  sub- 
family.     There  are  about  thirty  species. 

The  ants  of  this  genus  are  well  known  to  the  residents  in 
Australia,  where  they  are  called  "  1  mil- 
dog  ants."  They  form  large  mounds  of 
earth  for  their  nests.  The  workers,  and 
females  (Fig.  76)  are  much  alike  except 
during  the  period  when  the  latter  are 
still  carrying  their  wings.  The  males, 
however,  differ  considerably,  being  of 
more  slender  form,  and  possessing  only 
insignificant  mandibles,  and  straight 
antennae  with  a  quite  short  basal  joint. 

Forel  considers  Myrmecia  to  be  the 
most  formidable  of  all  the  ants  ;  the 
hills  are  said  to  be  sometimes  five  feet 


FIG.  /  6.  —  Myrmeaa  jtyrifo. 

high,  and  the  colonies  are  immense  in  Australia.  Female  after 
numbers,  while  the  Insect  is  an  inch  or  casting  wings' 
more  in  length,  and  armed  with  a  very  powerful  sting,  the  use 
of  which  on  the  human  body  is  said  to  give  rise  in  some  cases 
to  serious  symptoms.  On  the  other  hand,  we  have  seen  state- 
ments to  the  effect  that  the  sting  of  Myrmecia,  has  only  very 
evanescent  sequelae  ;  it  is  also  said  that  the  ant-hills  have  only 
a  slight  elevation,  so  that  probably  both  these  points  differ 
according  to  the  species.  It  appears  from  a  communication  of 
Miss  Shepherd's  that  the  formidable  Myrmecia,  forficata  has  its 
larvae  destroyed  by  a  parasitic  Hymenopteron  (Eucharis  myr- 
meciae*)  of  brilliant  colour  and  considerable  size,  so  that  we  have 
the  curious  fact  of  the  hordes  of  this  most  formidably  armed  ant. 

e/ 

which  possesses  also  large  eyes,  falling  a  victim  to  a  brilliant  and 
very  conspicuous  Insect.  Particulars  of  this  case  of  parasitic  attack 
are  still  wanting.  There  are  other  cases  known  of  the  larvae  of 
ants  being  destroyed  by  parasitic  Diptera  and  Hymenoptera,  but 
in  none  of  them  have  any  sufficient  observations  been  made  as  to 
the  mode  in  which  the  attack  is  made.  Lowne  says  that  M.  t/n/uxn 
itself  attacks  large  beetles  of  the  genus  Anoplognathus  and  buries 
them  ;  and  he  also  adds  the  very  curious  statement  that  M.  niyro- 
cincta,  when  running,  is  able  to  take  leaps  of  a  foot  in  length. 
The  Odontomaehi  were  formerly  considered  a  distinct  sub- 

v 

family,    distinguished    by    the    peculiar    mandibles    (Fig.    77). 


1/4  HYMENOPTERA  CHAP. 

Many  of  the  Ponerides  have  elongate  mandibles,  but  they  are 
inserted  at  the  sides  of  the  front  of  the  head,  not  in  the  middle 
of  the  front.  These  organs  in  some  species  of  Odontomachi 
serve  as  levers:,  by  aid  of  which  the  Insect  can  execute  considerable 
leaps.  In  only  a  few  species  are  the  males  known  ;  Mayr  and 
Forel  state  that  they  are  destitute  of  the  peculiar  mandibles 
characteristic  of  the  worker. 

The  unique  European  representative  of  the  Odontomachi, 
Anochetus  ghiliani,  occurs  in  Andalusia.  Near  Tangier  Mr. 
George  Lewis  found  it  to  be  not  uncommon  ;  but  the  sexes  are 

not  known,  and  it  even  appears  doubt- 
ful   whether    there    exists    any    well- 
,  marked  division  between   workers  and 

female.  Lewis  observed,  among  the 
ordinary  forms,  individuals  with  longer 
bodies,  usually  one  in  a  nest,  and  he 
supposed  these  to  be  females  ;  Saun- 
ders,  on  examining  these  examples, 
found  them  to  possess  distinct  ocelli, 
and  therefore  agreed  with  Lewis  as  to 
their  being  the  female  sex.  Dr.  Emery 

subsequently     examined     these     same 

FIG.  77.  —  Anochetus  ghiliani,  •  j  i         i          •  ^ 

worker.    Tangier  specimens,  and    took   what   is  scarcely 

a  different  view,  viz.  that  they  are  not 

females  but  an  intermediate  form;  and  he  also  expressed  the 
opinion  that  "  the  true  female  may  not  exist."  The  male  of 
Anochetus  is  not  known.  The  female  of  A.  mayri,  a  Neotropical 
.species,  has  rudimentary  wings. 


Sub-fam.  5.   Dorylides.  —  Clypens  extreme///  *///>///,  the 

in  *<•  rt  <'<1  very  near  flic  front  margin  of  the  head.  Hind 
laxly  nxniilly  elongate  anil  subcylindricol,  with  an  imperfect 
l><'ilircl  formed  by  f/ie  constriction  of  tlie  Imrk  of  tlie  first 
segment,  but  occasionally  tin  re  nee  tiro  tiodrs  in  the  workers. 
Distinctions  bctn-een  tlie  hro  sexes,  mnl  between  the  workers 
i/n</  xe,ee<]  forms,  enormous.  tlie  ijiieen*  truly  ivingless.  The 
female*  <i  n<l  worker*  nxiiiilly  hfiiif/,  or  <tt  onyrnte  destitute  of 
fiieefteil  rt/rs.  (In  Ecilonini  /lie  antennae  are  not  inserted, 
i/nite  ill  I  lie  front  of  the  head,  and  there  arc  ttco  nudes  in  the 
pedicel.^) 


IV 


DORYLIDES — WANDERING  ANTS 


175 


We  have  reserved  to  the  end  of  the  ants  the  consideration  of 
the  two  groups  Dorylides  and  Amblyoponides,  recent  investigations 
having  rendered  it  somewhat  doubtful  whether  they  can  be 
maintained  as  distinct  from  Ponerides.  The  chief  character  of 
the  Dorylides  is  that  the  males  are  much  less  ant-like  in  form 
than  they  are  in  the  other  groups,  and  that  the  distinction 
between  the  females  and  workers  are  enormous.  The  little  that 
is  known  as  to  the  males  and  females  of  this  group  suggests 
the  view  that  these  sexes  may  offer  sufficient  reason  for  keep- 
ing the  Dorylides  as  a  group  distinct  from  the  other  ants ;  but 
it  must  be  admitted  that  it  is  very  difficult  to  find  satisfactory 
characters  to  distinguish  the  workers  of  the  Dorylides  in  some 
cases  from  the  Ponerides,  in  others  (Eciton}  from  the  Myrmicides.1 

The  Dorylides  are  of  great  interest,  for  they  exhibit  the  remark- 
able phenomenon  of  a  nomadic 
social  life,  accompanied  by  im- 
perfect sight  in  the  wanderers. 
The  sub-family  includes  two 
apparently  distinct  groups : 
(1)  the  Ecitonini,  peculiar  to 
the  New  World,  and  having 
a  close  relationship  with  the 
Myrmicides  ;  and  (2)  the 
Dorylini  existing  chiefly  in 
the  eastern  hemisphere,  and 
related  closely  by  its  workers 
to  the  Ponerides  and  Ambly- 
oponides. (i.)  The  ECITONINI 
consist  of  the  species  of  the 
genus  Eciton,  the  wandering 
ants  of  America,  and  of  Labi- 
dus,  which  there  is  now  good 
reason  for  believing  to  con- 
sist of  the  males  of  Eciton. 
The  female  is  still  uncertain.  The  Eciton  are  nomad  ants 
having  no  fixed  abode,  but  wandering  from  place  to  place  in 
search  of  prey,  and  forming  temporary  resting-places.  The 


FIG.  78. — Various  forms  of  worker  of 
hamatum.     Guatemala. 


1  For  a  valuable  revision  of  Dorylus  and  its  allies  see  Emery,  Zool.  Jahrb.  Syst. 
viii.  1895,  pp.  685,  etc.  We,  however,  doubt  the  wisdom  of  extending  the  sub- 
family so  as  to  include  Cerapachys,  Parasyscia,  etc. 


176  HVMENOPTERA 


CHAP. 


species  are  rather  numerous,  and  the  habits  of  several  have  been 
described  by  Bates,  who,  however,  was  not  acquainted  with  some 
of  the  most  peculiar  features  in  their  biology,  these  having  been 
since  revealed  by  Belt  and  AY.  Miiller. 

These  ants  are  predaceous  in  their  habits,  and  some  of  the 
species  travel  in  vast  hordes ;  they  occasionally  enter  houses  and 
clear  them  of  much  of  the  vermin  with  which  they  may  be 
infested.  They  have  no  facetted  eyes,  some  of  the  forms  being 
quite  blind,  while  others  have  a  pair  of  peculiar  lenses  in  the 
position  normally  occupied  by  the  compound  eyes.  Usually 
there  are  two  castes  of  the  workers,  and  in  some  species  these  are 
very  different  from  one  another,  the  mandibles  being  in  the 
larger  form  very  elongate,  cylindrical  and  unfit  for  industrial 
purposes,  while  the  individuals  of  the  smaller  caste  have  the 
outer  jaws  shorter,  with  their  edges  apposed  and  coadapted :  in 
other  species  individuals  with  mandibles  differentiated  from  the 
normal  form  do  not  exist.  The  nomad  habits  of  these  ants  were 
described  by  Bates,  but  the  detection  of  their  temporary  resting- 
places  was  reserved  for  Belt,  who  found  that,  after  their  plundering 
raids,  they  retired  to  a  place  of  concealment,  and  there  clustered 
t<  >gether  in  a  compact  mass  like  a  swarm  of  bees.  Belt  says  : 
"  They  make  their  temporary  habitations  in  hollow  trees  and 
sometimes  underneath  large  fallen  trunks  that  offer  suitable 
hollows.  A  nest  that  I  came  across  in  the  latter  situation  was 
open  at  one  side.  The  ants  were  clustered  together  in  a  dense 
mass,  like  a  great  swarm  of  bees,  hanging  from  the  roof,  but 
reaching  to  the  ground  below.  Their  innumerable  long  legs 
looked  like  brown  threads  binding  together  the  mass,  which 
must  have  been  at  least  a  cubic  yard  in  bulk,  and  contained 
hundreds  of  thousands  of  individuals,  although  many  columns 
were  outside,  some  bringing  in  the  pupae  of  ants,  others  the  legs 
and  dissected  bodies  of  various  Insects.  1  was  surprised  to  see 
in  this  living  nest  tubular  passages  leading  down  to  the  centre 
of  the  mass,  kept  open,  just  as  if  it  had  been  formed  of  inorganic 
materials.  Down  these  holes  the  ants  who  were  bringing  in 
booty  passed  with  their  prey.  I  thrust  a  long  stick  doWn  to 
tlic  centre  of  the  cluster  and  brought  out  clinging  to  it  many 
ants  holding  larvae  and  pupae." 

Turning  now  to  the  LnhnJuf,  question:  many  American 
species  of  this  genus  have  long  been  known,  though  all  of  them 


iv  DORYLIDES WANDERING  ANTS  I  // 

by  the  male  sex  only.  The  discoveries  (to  be  subsequently 
alluded  to)  made  in  the  Old  World  as  to  the  relations  between  the 
driver  ants  and  Dorylus  raised  a  suspicion  that  Labidus  might 
In.-  the  male  of  Eciton,  the  distinctions  in  the  two  cases  being- 
very  analogous :  this  conjecture  has  been  almost  proved  to  be 
correct  by  the  recent  observations  of  Hetschko  and  W.  Miiller. 
The  latter,  wrho  observed  the  temporary  nests  of  Eciton  liamatum, 
confirms  Belt's  statements  as  to  the  ants  hanging  together  in 
clumps,  like  swarms  of  bees  ;  he  also  states  that  the  change  from 
one  temporary  abode  to  another  takes  place  at  night,  though,  as 
is  well  known,  the  hunting  forays  of  this  ant  are  carried  on  in 
the  daytime.  The  periods  of  migration  appear  to  be  determined 
by  the  time  at  which  all  the  larvae  have  assumed  the  pupal 
state,  this  at  any  rate  being  the  time  chosen  in  the  case  observed 
by  Miiller.  This  naturalist  bagged  a  part  of  one  of  the  nests 
by  the  aid  of  ether,  and  found  the  larger  portion  to  consist  of 
pupae ;  there  were  also  some  larvae  and  eggs ;  a  specimen  of 
Labidus  (L.  burchelli)  was  also  found  on  friendly  terms  with  the 
EC  it  on-  workers  ;  and  myrmecophilous  Coleoptera  were  discovered. 
The  pupae  are  enclosed  in  cocoons.  Persistent  search  failed  to 
reveal  any  female,  but  the  examination  was  made  under  great 
difficulties.  Miiller  also  states  that  the  earliest  pupated  larvae 
yield  soldiers,  the  latest  the  smallest  forms  of  workers.  From 
observations  made  by  Forel  on  a  pupa,  it  seems  probable  that 
a  wingless  form  of  male  may  be  found  to  exist.  If  there- 
i'i  >re,  as  appears  practically  certain,  Labidus  is  the  winged  male  of 
Eciton,  it  is  probable  also  that  males  of  more  or  less  worker-like 
form  exist,  as  is  now  known  to  be  the  case  in  some  other 
Formicidae. 

We  may  here  notice  a  peculiar  apterous  female  ant  recently 
described  by  Andre  under  the  name  of  Pscudodictkadia  incerf". 
He  thought  this  might  prove  to  be  the  female  of  Eciton- 
Lubidus ;  but  his  description  and  figure  are  imperfect,  and  do  not 
greatly  support  his  idea  of  a  connection  between  Eciton  and 
Psc  ti  dodic  tkadia. 

ii.  The  group  DOKYLINI  includes  the  genus  Dorylus,  which  was 
founded  many  years  ago  for  Insects  very  like  Labidus.  As  in 
the  case  of  the  American  Insect  named,  males  only  were  known  ; 
two  or  three  allied  genera,  consisting  exclusively  of  individuals 
of  the  sex  mentioned,  were  subsequently  described.  In  the 

VOL.  VI  N 


178 


HYMENOPTERA 


CHAP. 


I 


regions  inhabited   by  these  males  numerous  species  of  blind  ants 

are  known,  but  only  in  the 
worker  form,  and  were,  or  still 
are,  referred  to  genera  called 
Typhlopone  and  Anomma.  No- 
thing that  could  be  considered 
to  be  a  female  pertaining  to 
any  of  these  Insects  was  dis- 
covered until  Gerstaecker  de- 
scribed under  the  generic  name 
Dicthadia  an  extraordinary 
apterous  female  ant  found  in 
Java,  and  it  was  suspected 
that  it  might  be  the  long- 
expected  female  of  the  male 
Don/lus  and  of  the  worker 


Typhlopone  or  Anomma.  This 
remained  for  many  years  with- 
out confirmation,  but  in  1880 
Trinien  announced  the  dis- 

TiG.'iV.—Darylushelcolus.    Africa.    A,  male;    covery   ill    South  Africa    of    ail 
B,   female  (Dicthadia)  ;   C,  worker   major  „ 

(T>/j>?i/<ij><>,<c) ;  D,  worker  minor.    (After  enormous  apterous  female  ant, 
Emer>"-)  allied    to    Dicthadia;    it    had 

been  disinterred  from  a  nest  of  small  red  ants  believed  (wrongly) 
to  be  Anomma.  As  Dorylus  had  been  previously  found  in  con- 
nection with  allied  worker  ants  it  has  since  then  been  clear  that 
notwithstanding  the  enormous  differences  existing  between  these 
three  forms  they  may  all  pertain  to  one  (or  to  closely  allied) 
species.  From  this  summary  the  student  shotild  understand  that 
he  will  find  in  myrmecological  literature  many  references  to  two 
or  three  genera  that  really  belong  to  one  species. 

The  workers  of  the  Dorylini  at  present  known  are  without 
exception  quite  blind,  and  are  believed  to  be  all  of  predaceous 
habits;  it  is  thought  by  some  that  they  have  no  fixed  abodes, 
but,  like  the  Ecitonini,  frequently  change  their  residence,  and  it 
has  been  suggested  that  in  doing  so  they  make  use  of  the  nests 
of  other  ants  as  temporary  abodes ;  all  these  points  are,  however, 
still  unsettled,  and  as  there  are  several  genera  it  is  not  unlikely 
that  considerable  variety  will  be  found  to  prevail.  The  driver 
ants  of  Africa,  belonging  to  the  genus  Anomma,  are  in  some 


IV 


DORYLIDES DRIVER  ANTS 


179 


FIG.  80. — Body  of  male  of  Dorylus  sp.  Uelagoa  Bay. 
a,  pronotuni  ;  t>,  r,  divisions  of  mtsonotum  ;  d, 
nietanotum  ;  e,  propodeum  ;  ./',  first  abdominal  seg- 
ment ;  (j.  //,  points  of  insertion  of  anterior  and  pos- 
terior wings. 


respects  similar  to  Eciion  in  luibits,  as  they  enter  human  habita- 
tions and  cause  nearly  everything  else  to  quit ;  it  is  probable 
that  they  are  also  exclusively  carnivorous.  Savage  detected  the 
nests  of  A.  arc  ens,  but  the  account  he  has  given  of  them  is  too 
vague  to  permit  one  to  decide  whether  the  assemblages  he  saw 
were  of  a  nomad  kind.  The  workers  of  this  species  vary  greatly 
in  size,  and  Emery  has 
recently  stated  that 
lie  believes  all  the 
supposed  species  of 
the  genus  to  be 
merely  varieties  of  A. 
burmeisteri.  The 
female  of  the  driver 
ants  is  still  quite 
unknown.  A  Dorylus 
has  been  ascertained 
to  be  the  male  of  Typlilopone.  The  male  Dorylus  (Figs.  *79,  A, 
and  80)  is  of  great  interest,  for  the  propodeum  is  in  a  more  primi- 
tive form  than  it  is  in  any  other  petiolate  Hymenopteron  known  to 
us,  while  at  the  same  time  the  pronotum  and  mesonotum  are  very 
highly  developed.  The  genus  Typldatta  Sin.  has  been  recently 
identified  by  Wroughton  and  Forel  as  the  worker-condition  of 
which  Aenictus  is  the  winged  male.  The  genus  Alaopone  will 
probably  be  found  to  have  some  species  of  Dorylus  as  its 
male. 

The  females  of  the  Dorylides  are  amongst  the  rarest  of  Insects, 
and  are  also  amongst  the  greatest  of  natural  curiosities.  Although 
worker  ants  and  female  ants  are  merely  forms  of  one  sex — the 
female — yet  in  this  sub-family  of  ants  they  have  become  so 
totally  different  from  one  another  in  size,  form,  structure,  and 
habits  that  it  is  difficult  to  persuade  oneself  they  can  possibly 
issue  from  similar  eggs.  In  the  Insect  world  there  are  but  few 
cases  in  which  males  differ  from  females  so  greatly  as  the 
workers  of  Dorylides  do  from  the  females,  the  phenomena  finding 
their  only  parallel  in  the  soldiers  and  females  of  Termites ;  the 
mode  in  which  this  difference  is  introduced  into  the  life  of  the 
individuals  of  one  sex  is  unknown.  The  largest  of  all  the 
Dorylides  are  the  African  Insects  of  the  genus  fihognnts.  Only 
the  male  is  known. 


I  80  HYMENOPTERA 


CHAP. 


The  specimens  of  female  Dorylides  that  have  been  detected  may, 
after  fifty  or  sixty  years  of  research,  be  still  counted  on  the  fingers. 
As  the  greatest  confusion  exists  in  entomological  literature 
owing  to  the  forms  of  a  single  species  having  been  described  as 
two  or  three  genera,  the  following  summary  of  the  principal 
names  of  genera  of  Dorylides  may  be  useful  :— 

Eciton  =  the  workers,  Labidus  =  male  :  ?  unknown. 

J'fii-Hi/ixJirf/iitt/ii/  :  female  only  known,  possibly  that  of  Eciton. 

Cheliomyrmex  :   workers  and  soldiers  only  known. 

Aenictus  =  the  male,  Typlilatt«  —  worker :      unknown. 

Rliogmus :    male  ;    female    unknown.      (According    to   Emery 
the  worker  is  very  small  and  like  Alaopone.} 

Anomma  :   only  worker  known  ;  male  probably  a  Dorylus. 

Dorylvs  =  male  ;  Dicthadia  =  9  :  Alaopone  and  TypJilopone  - 
workers. 


Sub-Fam.  6.  Amblyoponides. — Abdomen  destitute  of  distinct 
IH'ilirf]  ;  f/ie  articulation  between  the  first  and  second 
segments  behind  the  true  petiole  being  broad. 

"We   follow  Forel  in  separating  Amblyorjone  and  a  few  allies 
from    the    Ponerides,    because    the    abdominal    pedicel    is    more 

imperfect  than  in  any  other  ants.  It  is, 
indeed,  very  difficult  to  frame  a  definition 
that  will  include  the  Amblyoponides 
among  ants,  and  at  the  same  time  sepa- 
rate Formicidae  and  Scoliidae.  Forel  con- 
siders the  Amblyoponides  to  approach 
closely  to  certain  divisions  of  the  Scoliidae 
(Thyimides,  e.g.}.  Little  is  known  of  these 
\jf)  I  \.  Insects,  though  they  are  widely  distri- 
1  mtecl.  A  in  bli/npone,  is  found  in  Australia 
and  Xew  Zealand  ;  the  allied  genus 

f,  worker.   Sfiomafomma    has    a    ^ide    distribution, 
Tasmania. 

occurring  even    in    Europe.      The    social 

life  is  believed  to  be  imperfect,  and  the  habits  subterranean  and 
M'llmtary.  The  males  and  females  are  winged;  the  latter  much 
resemble  the  workers,  which  are  nearly  blind,  and  have  a  con- 
siderable general  resemblance  to  Anomma,  in  Dorylides. 

Association  of  Ants   with   other   kinds   of  Insects.    -We 
have  already  alluded  to  tin-   fact    that   a    few  species  of  ants   are 


iv  INSECTS  INHABITING  ANTS'-NESTS  I  8  I 

used  liy  other  species  as  attendants,  and  that  the  two  kinds  then 
live  together  quite  amicably ;  and  we  have  also  seen  that  a  few 
ants  live  in  association  with  other  species  on  terms  that  are  not 
yet  understood.  One  little  ant,  Formicoxenus  niti<lntux,  lives 
only  in  the  large  nests  of  Formica  rufa ;  these  ants  tolerate 
the  little  Form-iro,irn./>s,  which  so  far  as  is  known  does  them 
neither  sjood  nor  harm.  There  are  also  a  considerable  number  of 

O 

species  of  small  ants  that  are  in  the  habit  of  choosing  the  neigh- 
bourhood of  larger  species  for  their  dwelling-places;  in  some 
cases  the  nests  are  constructed  actually  within  a  portion  of  the 
edifice  of  the  more  powerful  species,  and  the  rule  then  appears 
to  be  that  these  neighbours  do  not  molest  one  another.  X<  it- 
withstanding  the  militant  lives  that  many  of  them  lead,  ants 
cannot  be  considered  as  of  generally  ferocious  disposition. 

But  the  most  remarkable  point  in  connection  with  their 
toleration  consists  in  the  fact  that  the  nests  of  many  species  are 
inhabited  by  quite  a  colony  of  foreign  Insects  of  various  Orders  ; 
many  of  these,  being  found  nowhere  else,  are  spoken  of  as  ants'- 
nest  or  Myrmecophilous  Insects.1  The  relations  of  ants  with 
other  Insects  are  of  the  most  varied  and  complex  character ; 
some  of  their  guests  live  with  them  on  terms  of  the  most  intimate 
association,  being  indeed  absolutely  dependent  for  their  existence 
on  the  good  offices  of  their  hosts  ;  others  of  the  ants'-nest  Insects 
are  enemies,  while  others  are  neutral  or  indifferent  to  the  ants. 
We  have  already  mentioned  that  the  guests  migrate  in  company 
with  their  hosts. 

Many  species  of  ants  derive  a  considerable  portion  of  their 
sustenance  from  the  sweet  substances  excreted  by  Aphidae. 
Ants  may  constantly  be  seen  occupied  with  clusters  of  Aphidae, 
and  it  is  said  that  the  ingenious  little  creatures  defend  from 
enemies  the  manufacturers  of  the  sweet-stuff  they  are  so  fond  of, 
even  going  so  far  as  to  form  barricades  and  covered  places  for  the 
isolation  and  protection  of  this  peculiar  kind  of  cattle  ;  a  few 
ants  keep  some  of  the  root -feeding  Aphidae  in  their  nests. 
Coccidae  and  other  Homoptera,  which  also  excrete  much  matter 
of  a  sugary  nature,  are  likewise  consorted  with  by  ants;  as  are 
also  the  larvae  of  some  butterflies  of  the  family  Lycaenidae ; 
these  latter  being  believed  to  furnish  to  the  ants  some  substance 

1  A    Catalogue  of  Myrmecophilous  and  Termitophilous  Arthropods  was   pub-' 
lished  by  Wasmanu,  Berlin  1894. 


I  82  HYMENOPTERA  CHAP. 


of  ;i  nutritious  kind.  The  Insects  we  have  spoken  of  are,  how- 
ever, rather  of  the  nature  of  ant-cattle,  and  the  fondness  of  the 
ants  for  them  is  not  very  remarkable.  The  relations  of  the  ants 
to  the  peculiar  species  of  Insects  that  live  only  in  or  around  their 
nests  are  much  more  extraordinary.  The  greater  number  of  these 
guests  belong  to  the  Order  Coleoptera,  and  of  these  there  are  many 
hundreds — probably  many  thousands — of  species  that  depend  on 
ants  for  their  existence.  The  family  Pselaphidae  furnishes  a 
large  number  of  ants'-nest  beetles,  and  it  appears  probable  that 
most  of  them  excrete  some 
sugary  substance  of  which  the 
ants  are  fond.  Many  of  these 
Pselaphidae  are  of  the  most 
fantastic  shapes,  more  especi- 
ally the  members  of  the  sub- 
family Clavigerides.  But  the 

0      ,,      ,  ,  FIG.  82. — The  beetle,  A temeles,  soliciting 

most    curious    of    all    the   ants-          food  from  an  ant.     (After  Wasmann.) 

nest  beetles  are  the  Paussidae, 

a  family  exclusively  dependent  on  ants,  and  having  the  curious 
faculty,  when  disturbed,  of  bombarding— that  is,  of  discharging 
a  small  quantity  of  vapour  or  liquid  in  a  state  of  minute 
subdivision  accompanied  by  a  detonation.  Many  species  of 
Staphylinidae  are  peculiar  to  ant's-nests,  and  most  of  them  are 
indifferent  or  inimical  to  their  hosts,  but  some  of  them,  such  as 
Atemeles  (Fig.  82)  and  Lomechusa,  are  doubtless  producers  of  sweet 
stuff  that  is  liked  by  the  ants.  The  ants  feed  some  of  their  special 
favourites  amongst  these  guests  in  the  same  manner  as  they  feed 
one  another,  viz.  by  opening  the  mouth,  causing  a  drop  of  liquid 
to  appear  on  the  lip,  and  remaining  passive  while  the  guest 
partakes  of  the  proffered  bonne  boucJie.  This  way  of  giving  food 
to  other  individuals  is  a  most  remarkable  feature  in  the  character 
of  ants;  it  is  not  the  same  system  that  they  adopt  in  feeding  the 
larvae,  for  they  then  make  a  series  of  actual  movements,  and 
force  the  nutriment  into  the  mouths  of  the  grubs.  Besides  the 
Insects  we  have  mentioned  there  are  also  Orthoptera,  Hemiptera, 
Poduridae  and  Thysanura,,  Acari,  and  small  Isopod  crustaceans 
that  live  exclusively  in  company  with  ants.  We  have  mentioned 
that  a  few  Hymenopterous  and  Dipterous  parasites  have  been 
detected  living  at  the  expense  of  ants ;  it  is  probable  that 
closer  observation  of  the  ant  larvae  and  pupae  in  their  nests 


iv  INSECTS  INHABITING  ANTS'-NESTS  183 

will   disclose   a   greater  number  of  the   parasites   of   this    latter 
class. 

Much  attention  has  been  given  to  the  relations  between  ants 
and  their  guests  by  Wasmann.1  He  arranges  them  in  four 
categories  ;  1,  "  Symphily  "  for  the  true  guests,  which  are  fed  and 
tended  by  the  ants,  the  guests  often  affording  some  substance 
the  ants  delight  in  ;  2,  "  Metochy,"  the  class  of  tolerated  guests, 
being  so  far  as  is  known  not  disagreeable  to  the  hosts ;  3, 
"  Synecthry,"  including  those  Insects,  etc.,  to  which  the  ants 
are  hostile,  but  which  nevertheless  maintain  themselves  in  the 
midst  of  their  foes ;  4,  Parasites,  dwelling  in  the  bodies  of  the 
adult,  or  of  the  young  ants.  Many  of  these  ants'-nest  Insects 
present  a  more  or  less  perfect  resemblance  to  the  ants  in  one  or 
more  points,  such  as  sculpture,  colour,  size,  or  form.  To  these 
resemblances  Wasmann  attaches  great  importance.  We  should, 
too,  notice  that  some  of  the  inquilines  '2  have  become  acquainted 
with  the  movements  and  habits  of  the  ants,  and  stroke  them  (as 
the  ants  do  one  another)  to  induce  them  to  disgorge  food  in  the 
manner  we  have  alluded  to.  According  to  Janet,  ants  of  the 
genus  Lasius  are  infested  by  Acari  of  the  genus  Antennophorus. 
The  ants  carry  the  mites,  which  assume  positions  so  as  not  to 
cause  greater  inconvenience  than  is  inevitable.  Moreover,  the 
ants  give  food  to  the  mites  when  requested,  and  behave  in  a  most 
obliging  way  to  them,  though  there  is  not  any  reason  for  supposing 
that  in  this  case  the  ants  derive  any  benefit  from  the  Symphily. 

The  relations  between  ants  and  plants  have  been  of  late  years 
much  discussed.  We  have  already  briefly  alluded  to  the  subject 
when  speaking  of  the  Pseudomyrmini.  We  will  here  only  remark 
that  ants  frequent  plants  not  only  for  the  purpose  of  securing  the 
sweet  stuff  excreted  by  the  Aphidae  that  live  on  them,  but  also 
for  the  sake  of  getting  the  sweet  products  the  plants  themselves 
afford.  Mr.  Aitken,  speaking  of  ants  in  India,  says :  "  I  have 
come  to  the  conclusion  that  one  of  the  most  important  sources  of 
food-supply  which  ants  have  is  the  sacchariferous  glands  to  be 
found  at  the  bases  of  so  many  leaves."  It  is  supposed  that  the 
ants  are  on  the  whole  beneficial  to  the  plants  that  thus  afford  them 
supply  ;  and  this  fact  is  considered  by  many  to  afford  an  adequate 
explanation  of  the  existence  of  these  interesting  relations. 

1  For  a  summary  of  this  subject  see  Wasmann,  Congr.  internal.  Zool.  Hi.  1896, 
pp.  411-440.  2  For  explanation  of  tliis  term  see  vol.  v.  p.  524. 


CHAPTER   V 

COLEOPTEKA OR    BEETLES 

Order  V.  Coleoptera. 

Apparently  wingless  Insects  when  at  rest,  but  really  with  four 
wings;  the  elytra,  or  anterior  pair,  shell-like,  reposing 
an.  the  back  of  the  body  and  fitted  together  accurately 
a  font/  the  middle  I//  a  straight  suture;  the  posterior  pair 
membranous,  folded  together  under  the  elytra.  Mouth  with 
mandibles;  lower  lip  not  divided  along  the  middle.  Meta- 
//i<i/'/>/iosis  great  and  very  abrupt ;  the  larra  being  a  grub  or 
maggot,  which  changes  to  a •  jmpa  (usually  soft}  in  which  the 
external  structure  of  the  perfect  Insect  is  conspicuous. 

COLEOPTERA — or  Beetles — are  chiefly  distinguished  from  other 
Insects  by  the  solidity  of  their  external  integument,  and  by  the 
peculiar  nature  of  the  first  pair  of  their  alar  organs,  which  do 
not  serve  as  instruments  of  flight,  but  as  shells  for  protecting  the 
upper  face  of  the  after-body,  which,  unlike  the  other  parts,  remains 
as  a  rule  soft  and  membranous.  These  modifications  of  structure, 
though  apparently  slight,  must  be  really  extremely  advantageous, 
for  beetles  are  the  predominant  Order  of  Insects  in  the  existing 
epoch.  They  depart  from  most  other  Insects  in  being  less  aerial  in 
their  habits  ;  therefore,  notwithstanding  their  enormous  numbers, 
they  do  not  meet  the  eye  so  frequently  as  flies,  bees,  or  butter- 
flies. The  parts  of  the  hard  outer  skeleton  are  beautifully 
fitted  together,  and  as  their  modifications  are  easily  appreciated 
they  offer  as  fascinating  a  subject  for  study  as  do  the  skeletons 
of  Yertebrata.  The  habits  of  beetles  are  so  extremely  varied 
that  it  is  but  little  exaggeration  to  say  that  Coleoptera  are  to 
be  found  everywhere,  when  looked  for.  The  number  of  species 
at  present  known  is  probably  about  150,000.  Of  these  some- 
where about  3300  have  been  found  in  Britain.  The  structure 


CHAP.  V 


COLEOPTERA BEETLES 


I85 


of  the  hard  parts  of  the  skeleton  is  of  importance,  as  the  classi- 
fication of  this  enormous  number  of  species  is  entirely  based 
thereon  ;  it  will  be  readily  understood  from  the  accompanying 
diagram  (Fig.  83).  The  general  proportions  of  the  chief  parts 
of  the  body  call  for  a  few  remarks.  The  prothorax  is  remarkably 
free,  and  is  therefore  capable  of  a  much  greater  amount  of  move- 
ment independent  of  the  after-body  than  it  is  in  other  Insects. 
The  mesothorax  is,  on  the  other  hand,  much  reduced  ;  its  chief 
function  in  the  higher  forms  is  to  support  the  elytra,  and  to 


Fru.  83. — Under- surface  of  a  beetle, 
Harpalus  caliyinosus ;  legs  and 
antenna  of  one  side,  and  some  parts 
of  the  mouth  removed.  A,  an- 
tenna ;  B,  mandible  ;  C,  labruni  ; 
D.  ligula  ;  E,  paraglossa ;  F.  labial 
palp  ;  G,  inner  lobe  of  maxilla  ; 
H,  outer  lobe  (palpiform)  of 
maxilla  ;  I,  maxillary  palp  ;  K, 
mentum  ;  L,  gena  ;  M,  gula  :  N, 
huccal  fissure  ;  V,  plates  of  ven- 
tral segments.  1,  Prostermim  ; 
2.  prosternal  episternum  ;  3,  pro- 
sternal  epimerou  :  4,  anterior  and 
middle  coxal  cavities  ;  5,  iuflexed 
side  of  pronotum;  6,  nifsosterimm  ; 
7,  mesosternal  episternum  ;  8, 
mesosternal  epimeron  ;  9,  nieta- 
sternum  ;  10,  posterior  division  of 
metasternum  or  ante-coxal  piece  ; 
11,  metasternal  episternum  ;  12, 
metasternal  epimeron  ;  13,  epi- 
pleuron  or  inflexed  margin  of  ely- 
tron ;  14,  ventral  or  ambulatory 
setae  ;  15,  trochanter  ;  16,  pos- 
terior coxa  ;  17,  femur  ;  18,  tibia  ; 
19,  tarsus.  (Modified  from  Le- 
coiite  and  Horu.) 


help  to  keep  them  together  by  means  of  its  scutellum.  The 
metathorax,  on  the  contrary,  is  largely  developed,  except  in  the 
rather  numerous  forms  that  are  entirely  deprived  of  powers  of 
night.  The  composition  of  the  abdomen  has  been  a  subject  of 
great  difference  of  opinion.  Its  upper  surface  is  usually  entirely 
covered  by  the  elytra;  the  parts  visible  on  the  lower  surface  are 
called  ventral  segments,  and  are  usually  five  in  number.  Although 
these  five  plates  may  constitute  all  that  is  superficially  visible  of 
the  abdomen,  yet  if  the  elytra  are  taken  off  it  is  found  that  a  larger 
number  of  segments — usually  seven  or  eight — are  visible  on 
the  dorsum.  This  seeming  discrepancy  of  number  between  the 


'-14 


I  86  COLEOPTERA 


CHAP. 


dorsal  and  ventral  plates  is  due  to  two  facts ;  1,  that  the 
hind  coxae  have  a  great  and  complex  development,  so  that  they 
conceal  the  true  base  of  the  venter,  which,  moreover,  remains 
membranous  to  a  greater  or  less  extent,  and  thus  allows  much 
mobility,  and  at  the  same  time  a  very  accurate  coadaptation 
between  the  hard  parts  of  the  venter  and  the  metasteruum  l  ;  2, 
that  the  terminal  segments  are  withdrawn  into  the  interior  of 
the  body,  and  are  correspondingly  much  modified,  the  modifica- 
tion being  greater  in  the  case  of  the  ventral  than  in  that  of  the 
dorsal  plates.  The  anatomy  of  the  parts  of  the  abdomen  that 
are  not  externally  visible  has  not  been  adequately  studied  by 
coleopterists,  but  Yerhoeff  has  inaugurated  a  careful  study  of 
the  comparative  anatomy  of  the  terminal  segments 2 ;  unfor- 
tunately, however,  he  has  not  so  thoroughly  studied  the  modifi- 
cations at  the  base,  and  as  it  is  not  clear  that  these  are  so 
uniform  as  he  has  taken  for  granted,  it  is  possible  that  his  num- 
bering of  the  segments  may  have  to  be  in  some  cases  modified. 
The  retracted  plates  or  segments  are  so  intimately  connected 
with  the  internal  copulatory  organs  that  it  is  no  easy  matter  to 
interpret  them.  For  the  nomenclature  of  these  parts  we  must 
refer  the  student  to  Verhoeff's  later  works.  He  considers  the 
abdomen  as  composed  of  ten  segments,  the  dorsal  plates  being 
demonstrable,  while  the  tenth  ventral  plate  is  usually  absent. 
The  anal  orifice  is  placed  immediately  beneath  the  tenth  dorsal 
plate,  and  above  the  genital  orifice,  which  lies  behind  and  above 
the  ninth  ventral  plate.  Peytoureau  admits  a  diversity  in  both 
the  number  of  segments  and  the  position  of  the  orifice.  These 
studies  in  comparative  anatomy  are  surrounded  with  difficulties, 
and  no  morphological  conclusions  based  on  them  can  be  con- 
sidered as  final  until  they  have  been  confirmed  by  observation 
of  the  development  of  the  parts. 

The  elytra — or  wing-cases  —  frequently  have  a  remarkable 
sculpture,  the  use  of  which  is  unknown.  According  to  Hofbauer 
there  are  between  the  outer  and  inner  layers,  glands  secreting  a 

1  An  interesting  exception  occurs  in  the  Malacodermidae,  where  this  coadaptation 
is  wanting,  or  is  imperfect ;  they  are  frequently  considered  to  be  the  most  primitive 
of  existing  beetles. 

2  In  a  series  of  memoirs  in  various  German  periodicals  during  the  last  five  or  six 
years  (see  especially  Deutsche  ent.   Zcit.  1893  and  1894,  also  subsequent  years  of 
Arch.  Xaturgcs.}.     It  should  be  noticed  that  in  the  course  of  his  studies  Verhoetf 
has  modified  some  of  his  earlier  views. 


BEETLES  187 


fluid  that  reaches  the  surface  through  small  pores.  Hicks  sup- 
posed that  he  detected  nerve  cells.  Meinert  is  of  opinion  that 
the  elytra  correspond  to  the  teguke  of  Hymenoptera  rather  than 
to  the  wings  of  other  Insects,  but  the  little  evidence  that  exists  is 
not  favourable  to  this  view.  The  two  elytra  are  usually,  in  repose, 
very  perfectly  fitted  together  by  a  complete  coadaptation  along  the 
middle  of  the  body,  so  that  it  is  difficult  to  separate  them  ;  this 
line  of  junction  is  called  the  suture.  There  are  forms  in  which 
the  coadaptation  is  quite  imperfect  (Malacodermidae)  and  some 
in  which  it  does  not  exist  at  all  (Meloty.  The  wings  proper  of 
beetles  correspond  to  the  posterior  pair  in  other  Insects,  and  are 
much  more  irregular  in  nervuration  than  those  of  most  other  In- 
sects, correlative,  it  is  supposed,  with  the  folding  they  are  subjected 
to  in  order  to  get  them  beneath  the  wing-cases.  There  are  large 
numbers  of  species,  genera,  and  groups  of  genera,  all  the  members 
of  which  have  the  wings  so  much  reduced  in  size  as  to  be  quite 
useless  for  purposes  of  flight.  These  forms  are  called  apterous, 
though  they  are  not  really  so,  for  the  elytra  (which  are  really 
the  anterior  wings)  are  present,  and  even  the  posterior  wings 
are  not  truly  absent  in  these  cases,  though  they  are  sometimes 
so  extremely  rudimentary  as  to  elude  all  but  the  most  careful 
observation.  The  number  of  forms  in  which  the  elytra  are 
absent  is  extremely  small ;  this  condition  occurs  only  in  the 
female  sex  ;  it  is  usually  confined  to  cases  in  which  the  female 
is  larva-like  in  form ;  but  in  the  extraordinary  Mediterranean 
Lamellicorn  genus,  Packypus,  the  females  are  destitute  of  wings 
and  elytra,  though  the  anterior  parts  of  the  body  are  normally 
formed :  these  individuals  live  underground  and  rarely  or  never 
emerge.  When  the  wings  are  absent  the  elytra  are  frequently 
soldered ;  that  is  to  say,  united  together  along  the  suture  by  some 
sort  of  secondary  exudation  ;  this  union  occurs  in  every  degree  of 
firmness,  and  appears  to  be  variable  in  the  individuals  of  one 
species ;  probably  in  accordance  with  the  age  of  the  individual. 
In  most  beetles  the  elytra  are  not  only  themselves  closely  con- 
nected, but  are  also  very  accurately  coadapted  with  the  sides  of 
the  body,  except  at  the  tip.  Sometimes  a  coadaptation  occurs 
between  the  tips  of  the  elytra  and  the  body,  but  not  at  the  tip  of 
the  latter.  In  such  cases  one  or  more  dorsal  plates  are  left  ex- 
posed :  the  last  of  such  exposed  dorsal  plates  is  termed  pygidium  : 
a  similar  plate  anterior  to  the  pygidium  is  called  propygidium. 


I  88  COLEOPTERA 


CHAP. 


Larvae. — Owing  to  the  difficulty  of  rearing  Coleoptera,  less 
is  perhaps  known  of  their  life-histories  than  of  those  of  other 
Insects.  They  exhibit,  however,  extreme  diversity  correlative 
with  the  great  specialisation  of  so  many  beetles  to  particular 
kinds  of  life.  Most  beetles  must  have  exactly  the  right  condi- 
tions to  live  in.  The  larvae  of  many  forms  are  known.  They 
are  composed  of  a  head,  three  thoracic  segments  (usually  very 
distinct),  and  a  number  of  abdominal  segments  varying  from  eight 
to  ten.  Coleopterous  larvae  are  usually  described  as  having  nine 
abdominal  segments;  and  it  is  but  rarely  that  ten  can  be  readily 
detected ;  they  are,  however,  visible  in  various  forms,  as  is  the 
case  in  the  form  figured  (Fig.  84).  A  great  many  of  them 
possess  a  peculiar  pseudopod  at  the  underside  of  the  body  near 
or  at  the  extremity  ;  it  can  in  many  cases  be  entirely  retracted 
into  the  body,  and  is  generally  described  as  being  the  pro- 
truded termination  of  the  ali- 
mentary canal.  Inspection  of  a 
series  of  larvae  shows  that  it 
represents  a  body  segment :  it  is 
FIG.  84. —Larva  of  a  i.eetie,  Family  sometimes  armed  with  hooks. 

Cerambycidae   (I.Aroniiti     ii<i~in<-luitt().    mi  •          p  n     J.T  i 

The  first  spiracle  is  placed  just  at  the  Three  pairs  of  small  thoracic  legs 
hind  margin  of  the  large  prothoracic  are  often  present,  but  are  very 
segment.  (From  La  Massaiie. )  Pj  m, 

often    completely    absent.       These 

thoracic  legs  may  be  present  in  the  young  larva,  but  not  in  the 
older  (Bruchus).  The  usual  number  of  spiracles  is  nine  pairs, 
•  me  prothoracic,  eight  abdominal;  but  this  is  subject  to  many 
exceptions,  and  mesothoracic  and  metathoracic  stigmata  are  occa- 
sionally found.  The  figures  we  give  in  the  following  pages  will 
enable  the  student  to  form  some  idea  of  the  variety  of  form 
exhibited  by  beetle  larvae. 

Pupation  usually  takes  place  in  a  cavity  in  the  earth,  or 
near  the  feeding-place,  but  a  great  many  species  form  a  cocoon, 
composed  either  of  fragments  of  earth  or  of  wood,  and  slightly 
cemented  together.  A  few  suspend  themselves  by  the  tail  after 
the  manner  of  butterfly  caterpillars  (Cassididae,  Coccinellidae). 
The  pupae  are  usually  extremely  soft,  their  appendages  not 
being  fastened  to  the  body.  But  some  pupae  (Staphylinides) 
are  truly  obtected,  having  a  hard  shell  and  the  rudimentary 
appendages  fastened  by  exudation  to  the  body,  like  Lepi- 
dopterous  pupae,  and  others  (Coccinellidae)  are  intermediate 


BEETLES  189 


between  this  state  and  the  normal  soft  pupa.  The  pupal  state 
lasts  but  a  short  time,  from  one  to  three  weeks  being  the  usual 
period.  The  perfect  Insect  is  at  first  soft  and  almost  colourless, 
and  it  is  often  some  days  before  it  attains  its  complete  coloration 
and  hardness. 

Classification. — Owing  to  the  hardness  of  the  skeleton,  beetles 
shrivel  but  little  after  death,  so  that  the  form  and  relations  of 
the  various  sclerites  can  usually  be  detected  with  ease.  These 
sclerites  seem  to  be  remarkably  constant  (except  in  the  case  of 
sexual  distinctions)  within  the  limits  of  each  species,  and  are 
very  useful  for  the  formation  of  genera  and  groups  of  genera  : 
but  they  vary  so  much  outside  the  limits  mentioned  that  it  is 
very  difficult  to  make  use  of  them  for  defining  the  larger  groups. 
Hence  it  is  not  easy  to  frame  accurate  definitions  of  the 
families,  and  still  less  so  to  arrange  these  families  in  more  com- 
prehensive series.  The  natural  difficulty  has  been  much  increased 
by  the  habit  coleopterists  have  of  framing  their  definitions 
on  what  is  visible  without  the  aid  of  dissection.  Nevertheless 
considerable  progress  has  been  made.  "We  are  obliged  at  present 
to  adopt  upwards  of  eighty  families ;  and  we  are  able  to  dis- 
tinguish  on  positive  characters  five  series;  this  leaves  a  large 
number  of  forms  still  unclassified,  and  these  we  have  here 
associated  as  a  sixth  series,  which  we  have  called  Coleoptera  Poly- 
morpha.  This  series  corresponds  with  the  two  series  called  in 
books  Clavicornia  and  Serricornia.  As  it  is  admitted  to  be 
impossible  to  define  these  two  series,  we  think  it  much  better  to 
act  accordingly,  and  to  establish  for  the  present  a  great  group 
that  can  only  be  characterised  by  the  fact  that  its  members  do 
not  belong  to  any  of  the  other  five  series.  No  doubt  a  larger 
knowledge  of  development,  coupled  with  the  advance  of  com- 
parative anatomy,  will  ultimately  bring  about  a  better  state  of 
affairs.  The  Strepsiptera,  with  one  family  Stylopidae,  are  only 
provisionally  included  among  the  Coleoptera.  These  six  series 
are  fairly  equal  as  regards  extent.  Though  the  Polymorpha 
includes  the  larger  number  of  forms,  yet  a  large  part  of  them 
belong  to  four  great  families  (Staphylinidae,  Buprestidae,  Elat- 
eridae,  Malacodermidae),  which  are  easily  recognisable,  so  that 
the  number  of  unmanageable  forms  is  not  really  great.  Indeed, 
an  acquaintance  with  the  external  anatomy  of  two  or  three 
dozen  species,  selected  as  typical,  would  enable  a  student  to  classify 


1 90  COLEOPTERA  CHAP. 

with    tolerable    certainty   the   vast  majority   of   species    that    he 
would  subsequently  meet  with. 

Series  1.  Lamellicornia. — Antennae  with  the  terminal  joints  leaf-like  (or 
broader  than  the  others,  if  not  actually  leaf-like),  and  capable  of 
separation  and  of  accurate  apposition.  Tarsi  five-jointed. 

Series  2.  Adephaga — (Caraboidea  of  some  authors). — Antennae  never  lamelli- 
f 01-111,  thin  at  the  end  ;  all  the  tarsi  five-jointed,  with  the  fourth 
joint  quite  distinct.  Maxillae  highly  developed,  with  the  outer 
lobe  slender  and  divided  into  two  segments  so  as  to  be  palpiiorm. 
Abdomen  with  six  (or  more)  ventral  segments  visible. 

Series  3.  Polymorpha. — Antennae  frequently  with  either  a  club,  i.e.  the 
distal  joints  broader  [Clavicorn  series  of  authors],  or  the  joints  from 
the  third  onwards  more  or  less  saw-like,  the  serrations  being  on  the 
inner  face  [Serricorn  series  of  authors];  but  these  and  all  the  other 
characters,  including  the  number  of  joints  in  the  feet,  very  variable. 

Series  4.  Hetcromcra. — Front  and  middle  tarsi  five-jointed,  hind  tarsi  four- 
jointed.  Other  characters  very  variable. 

Series  5.  Phytophaga. — Tarsi  four-jointed  [apparently],  but  with  a  small  addi- 
tional joint  at  the  base  of  the  fourth  joint  :  sole  usually  densely 
pubescent  [sometimes  the  feet  are  bare  beneath  or  bristly,  and 
occasionally  the  small  joint  at  the  base  of  the  fourth  joint  is  more 
distinct]. 

Series  6.   Rhynchophora. — Head   prolonged   in    front    to   form    a  beak  ;  gula 
indistinguishable.     [Palpi  usually  not  evident.]     Tarsi  four-jointed 
[apparently],   but   with    a   very  minute   additional  joint    at    the 
extreme  base  of  the  fourth  joint. 
Streps'iptera  (see  p.  '298). 

The  first  and  second  series,  with  much  of  the  third,  form  the 
Pentainera,  the  fifth  and  sixth  the  Tetramera  [or  Pseudotetra- 
inera  *].  The  term  Isomera  was  applied  by  Leconte  and  Horn 
to  a  combination  of  series  1,  2,  13,  and  5. 

Series  I.    Lamellicornia. 

Tarsi  five-jointed  ;  antennae  with  the  terminal  joints  (usually  three, 
sometimes  more),  broader  on  one  side,  so  as  to  form  a  peculiar 
cluli,  the  leaves  of  which  are  movable,  and  in  repose  are 
more  or  less  perfectly  eoadapted  so  as  to  hare  the  'appearance 
of  being  lut  one  piece. 

This  series  includes  three  families,  Passalidae,  Lucanidae,  and 
Scarabaeidae  :  the  latter  includes  an  enormous  majority  of  the 
>]><-<-ies,  and  in  them  the  structure  of  the  antennae  characteristic 
<jf  the  scries  is  well  developed;  but  in  the  other  two  families 

1   We  consider  this  term  inferior  to  Tetramera  for  nomenclatorial  purposes. 


LAMELLICORNS 


the  form  of  the  antennae  is  not  so  widely  different  from  that  of 

other  Coleoptera.      The  larvae  live  on  decaying  vegetable  matter, 

roots  or  dung.      They 

have    three    pairs   of 

legs,    and    are    thick 

clumsy 

curved 


grubs     with 

bodies,  the 
last  two  segments 
being  of  larger  size 
than  usual.  Many  of 
them  possess  organs 
of  stridulation,  and 
the  structure  of  their 
spiracles  is  very 
peculiar,  each  one 
being  more  or  less 
completely  sur- 
rounded by  a  chitin- 
ous  plate.  The 
spiracles  usually  form 

a        System 

C'losed     except    at    the 

moment  when  the 
skin  is  shed  and  the  tracheal  exuviae  are  detached.  Meinert T 
considers  these  spiracles  to  be  organs  of  hearing.  The  life  of  the 
larvae  is  passed  underground  or  in  the  decaying  wood  on  which 
the  Insect  feeds. 

Most  of  the  members  of  this  series  are  remarkable  on  account 
of  the  great  concentration  of  the  nerve-centres.  This  is  extreme 
in  Rhizotrogus,  where  there  are  only  two  great  ganglia,  viz.  the 
supra-oesophageal  and  a  great  ganglion  situate  in  the  thorax, 
and  consisting  of  the  conjoined  infra-oesophageal,  thoracic,  and 
abdominal  ganglia,  According  to  Brandt2  there  are  several 
distinct  forms  of  concentration  in  the  series  ;  the  Lucanidae  only 
participate  in  it  to  the  extent  that  the  perfect  Insects  exhibit 
fewer  ganglia  than  the  larvae  ;  the  latter  possess  two  cephalic, 
three  thoracic,  and  eight  abdominal  ganglia,  while  the  perfect 
Insect  has  the  abdominal  ganglia  reduced  in  number  to  six,  and 


FIG.    85.  —  Antennae   of   Lamellicoms.  1.    AWt«s  inter- 

entirely           niptus ;    -2,    Lucan-us    cerrus  <3  ;    3,  J'/K/I/KCUS    splen- 

didulus   9;   4,  Phileurus  didymus  ?;  5, 
fitllo  (J. 


1  J >(mske  SeM:  Mr.  (G),  viii.  No.  1,  1895. 

2  Horae  Soc.  ent.  lloss.  xiv.  1879,  ]>.  15. 


I92 


COLEOPTERA 


CHAP. 


they  are  placed  partially  in  the  thorax.  The  diminution  in 
number  takes  place  in  this  case  by  the  amalgamation  of  the  first 
two  abdominal  with  the  last  thoracic  ganglia. 

Fam.  1.  Passalidae. — Lcibrum  large,  mobile  ;  mentum  deeply 
cut  out  in  the  middle  for  the  accommodation  of  the  liyida  ;  the 
lamellae  of  the  anten/nt  In-onnlit  together  by  the  curling  up  of  the 
antenna.  The  elytra  entirely  cover  the  dorsal  suifuce  <>f  the  abdo- 
men,. There  are  four  or  five  hundred  species  of  this  family  known  ; 
they  are  usually  shining-black,  unattractive  beetles,  of  large  size, 


-I-  -I 


FIG.  86.— View  of  one 
7  side  of  nieso-  ami 
metathorax  of  a 
Passalid  larva  from 
Borneo  showing  the 
stridulating  organs. 
a,  b,  Portions  of  the 
metathorax  ;  c,  coxa 
of  2nd  leg;  d, striate 
or  stridulating  area 
thereon  ;  e,  basal 
part  of  femur  of 
middle  leg  ;  /',  hairs 
with  chitiuous  pro- 
cess at  base  of  each  ; 
g,  the  diminutive 
3rd  leg  modified 
for  scratching  the 
striated  area,  x  20. 


-I 


and  are  abundant  in  the  decaying  wood  of  tropical  forests.  They 
are  quite  absent  from  Europe,  and  there  is  only  one  species  in 
the  United  States  of  North  America.  The  larvae  are  very 
interesting,  from  the  fact  that  they  appear  to  have  only  four  legs. 
This  arises  from  the  posterior  pair  being  present  only  as  very 
short  processes,  the  function  of  which  is  to  scrape  striated  areas  on 
the  preceding  pair  of  legs  and  so  produce  sound.  In  the  specie^ 
figured  (Fig.  86)  this  short  leg  is  a  paw-like  structure,  bearing 
several  hard  digits ;  but  in  other  species  it  is  more  simple,  and 
without  the  digits.  The  perfect  Insect  has  no  sound-producing 
organs,  and  it  is  very  remarkable  therefore  to  find  the  larvae 


v  LAMELLICORNIA STAG-BEETLES  193 

provided  with  highly -developed  stridulatoiy  structures.  No 
auditory  organ  is  known,  unless  the  peculiar  spiracles  be 
such. 

Fam.  2.  Lucanidae  (Stag-beetles). — Labrum  indistinct,  fixed  ; 
mentum  not  excised ;  antennae  not  curled  in  repose,  with  but  little 
coadaptation  of  the  terminal  joints  ;  the  elytra,  entirely  cover  the 
dorsal  surface  of  the  abdomen.  The  Stag-beetles  are  well  known 
on  account  of  the  extraordinary  development  of  the  mandibles  in 
the  male  sex,  these  organs  being  in  some  cases  nearly  as  long  as 
the  whole  of  the  rest  of  the  Insect,  and  armed  with  projections 
or  teeth  that  give  the  Insects  a  most  formidable  appearance.  So 
far  as  we  have  been  able  to  discover,  these  structures  are  put  to 
very  little  use,  and  in  many  cases  are  not  capable  of  being  of 
service  even  as  weapons  of  offence.  The  males  are  usually 
very  much  larger  than  the  females,  and  are  remarkable  on 
account  of  the  great  variation  in  the  stature  of  different  indi- 
viduals of  the  same  species  ;  correlative  with  these  distinctions 
of  individual  size  we  find  extreme  differences  in  the  development 
of  the  head  and  mandibles.  Moreover,  the  small  male  specimens 
exhibit  not  merely  reductions  in  the  size  of  the  mandibles,  but  also 
show  considerable  differences  in  the  form  of  these  parts,  due, 
in  some  cases,  apparently  to  the  fact  that  only  when  a  certain 

length  of  the  mandible 
is  attained  is  there  any 
development  of  certain 
of  the  minor  projec- 
tions :  in  other  cases  it 
is  not  possible  to  adopt 
this  view,  as  the  small 
B  mandibles  bear  as  many 

FIG.  87.-HeadManaprothoraxofformsof  the  male  of  projections  ES    the    large 

a  stag-beetle  ;    Homoeoderns  mellyl  (Africa).     A,  forms  do,  Or  even    more. 

Large.  B.,  intermediate,  C,  small  forms.      (From  a  T 

photograph  by  ROberthtir.)  In     each     species     these 

variations    fall,   in    the 

majority  of  cases,  into  distinct  states,  so  that  entomologists  describe 
them  as  "  forms,"  the  largest  developments  being  called  teleodont, 
the  smallest  priodont ;  the  terms  mesodont  and  amphiodont  being 
applied  to  intermediate  states.  Leuthner,  who  has  examined  many 
specimens,  states  that  in  Odontolabis  sinensis,  no  intermediates 
between  the  teleodont  and  mesodont  forms  occur,  and  as  the 

VOL.  VI  0 


194 


COLEOPTERA 


CHAP. 


two  forms  are  very  different  they  are  liable  to  be  mistaken  for 
distinct  species. 

There  are  at  present  between   500  and   600   species  of  stag- 
beetles  known ;  the  Indo-Malayan  and  Austro-Malayan  regions 
being   richest   in   them.      Australia   possesses   many   remarkable 
and  aberrant  forms.      In   the   Ceratognathini — a  group   well  re- 
presented in  New  Zealand  as  well  as 
in  Australia — the  structure  of  the 
antennae  is  like  that  of  the  Scara- 
baeidae,  rather  than   of  the  Luca- 
nidae.       The   most   aberrant   form 
known    is,    however,   our    common 
Sinodendron  cylindricum ;   this  de- 
parts  in   numerous    features    from 
other    Lucauidae,    and    instead    of 
the  mandibles  of  the  male  being 
FIG.    w.— Sinodendron   cyiindricum.    more  largely  developed,  there  is  a 

A,  Larva;  B,  pupa.   New  Forest. 

horn    on    the    head ;     it     is    very 

doubtful  whether  this  Insect  should  be  allowed  to  remain  in 
the  family.  Little  is  known  of  the  habits  and  development  of 
Lucanidee,  except  in  the  case  of  three  or  four  species  that  are 
common  in  Europe. 

The  common  stag-beetle,  Lucanus  cervus,  is  our  largest  British 
beetle.  The  larva  much  resembles  that  of  Melolontlia  mdgaris, 
but  attains  a  larger  size,  and  the  anal  aperture  is  placed  longitu- 
dinally instead  of  transversely  ;  it  lives  in  decaying  wood,  or  eats 
the  roots  of  trees  without  being  injurious  ;  its  life  in  this  state 
lasts  about  four  years  ;  the  pupal,  period  is  passed  through  rapidly, 
and  the  perfect  Insect  may  remain  for  months  underground 
before  it  becomes  active ;  this  occurs  in  June  and  July.  This 
larva  stridulates  by  scraping  certain  hard  tubercular  ridges  on 
the  third  pair  of  legs,  over  a  specially  adapted  rough  area  at  the 
base  of  the  second  pair. 

The  Passalidae  and  Lucanidae  are  united  by  some  authorities 
as  a  group  called  Pectinicornia ;  the  term  Lamellicornia  being 
then  confined  to  the  Scarabaeidae.  The  Passalidae  appear,  how- 
ever, to  be  really  more  nearly  allied  to  the  Scarabaeidae  than  to 
the  Lucanidae. 

Fam.  3.  Scarabaeidae  (Chafers'). — The  leaflets  of  the  antennae 
are  well  coadapted,  and  are  susceptible  of  separation.  The  elytra 


v  LAMELLICORNIA — SCARABAEIDAE  195 

•usually  leave  the  pygidimii  uncovered.  The  number  of  visible 
i'1'ntral  segments  is  usually  six,  or  at  the  sides  seven,  not  Jive,  as  in 
Lucanidae  and  Passalidae.  This  is  one  of  the  most  important 
families  of  Insects.  About  13,000  species  are  already  known; 
as  some  of  them  are  highly  remarkable  creatures  on  account  of 
the  males  being  armed  with  horns,  they  are  figured  in  many 
works  on  natural  history.  There  is  great  variety  of  form,  and 
the  following  five  sub-families  may  be  adopted,  though  authorities 
are  by  no  means  agreed  as  -to  the  classification  of  this  extensive 
family,  which,  moreover,  lie  it  remarked,  is  increasing  by  the  dis- 
covery of  about  300  new  species  every  year. 

Abdominal  spiracles  plaivd  in  a  line  on  the  connecting  membranes,  and  en- 
tirely covered  by  the  wing-cases  (Laparosticti).  Sub-fain.  1.  CopRiDES.1 

Abdominal  spiracles  placed  almost  in  a  line,  but  only  the  basal  three  on  the 
connecting  membranes  ;  the  terminal  one  usually  not  covered  by  the 
wing-cases.  Sub-fain.  2.  MELOLONTHIDES. 

Abdominal  spiracles  placed  in  two  lines,  the  basal  three  on  the  connecting 
membranes,  the  others  on  the  ventral  segments  (Pleurosticti). 

The  claws  of  the  tarsi  unequal.  Sub-fam.  3.  RUTELIDES. 

The  claws  of  the  tarsi  equal  ;  the  front  coxae  transverse,  but  little  pro- 
minent in  the  descending  axis.  Sub-fam.  4.  DYNASTIDES. 

The  claws  of  the  tarsi  equal ;  the  front  coxae  more  prominent,  shorter 
transversely.  Sub-fam.  5.  CETONIIDES. 

i.  The  COPRIDES  form  an  immense  group  of  about  5000  species  ; 
they  differ  somewhat  in  habits  from  other  Lamellicorns,  inasmucb 
as  most  of  them  live  on  dung,  or  decaying  animal  matter ;  the 
sub-family  connects  with  the  Lucanidae,  so  far  as  superficial  char- 
acters go,  by  means  of  two  of  its  groups,  Trogini  and  Nicagini, 
the  latter  being  very  near  to  the  Ceratognathini  in  Lucanidae. 
So  little  is  known  as  to  the  morphology  and  development  of 
these  groups  that  it  is  not  possible  to  pronounce  an  opinion  as 
to  the  validity  of  this,  apparent  alliance.  Trox  stridulates  by 
rubbing  two  raised  lines  on  the  penultimate  dorsal  segment 
across  two  striate  ribs  on  the  inner  face  of  the  elytra ;  Geotrupes, 
on  the  other  hand,  produces  an  audible  sound  by  rubbing  together 
a  file  on  the  posterior  coxa  and  a  fine  ridge  on  the  contiguous 
ventral  segment.  The  larva  in  this  genus  has  a  different  organ 

1  In  this  sub-family  there  are  numerous  forms  iu  which  the  elytra  cover  the 
pygidium,  and  in  which  the  number  of  conspicuous  ventral  segments  is  reduced  to 
five  or  even  lour.  We  use  the  term  Coprides  as  equivalent  to  the  "Laparosticti" 
of  Lacordaire  (Gen.  Col.  iii.  1856)  ;  it  thus  includes  the  "Comlni"  and  "  Glaphy- 
rini  "  of  the  Cutaloyus  Coleopterorum,  vol.  iv.  Munich,  1869. 


1 96  COLEOPTERA  CHAP. 

for  stridulatiou  from  the  imago ;  it  is  placed  on  the  second  and 
third  pairs  of  legs,  the  latter  pair  being  much  reduced  in  size. 

The  most  interesting  division  of  the  Coprides  is  the  group 
Scarabaeini.  Xo  member  of  this  group  inhabits  the  British 
islands,  but  in  Southern  Europe,  and  in  still  warmer  lands,  these 
Insects  are  well  known  from  the  curious  habit  many  of  the  species 
have  of  rolling  about  balls  of  dung  and  earth.  The  long  hind 
legs  are  chiefly  used  for  this  purpose,  and  it  is  on  the  peculiar 
structure  of  these  limbs  that  the  group  has  been  established. 
Many  of  the  stone  Scarabaei  found  in  Egyptian  tombs  represent 
some  kind  of  Scarabaeini,  and  it  has  been  said  that  the  ancient 
Egyptians  looked  on  these  Insects  as  sacred  because  of  their 
movements.  These  must  certainly  appear  very  strange  to  those 
who  see  them  and  are  unacquainted  with  their  object.  It  is 
stated  that  the  dwellers  in  the  vallev  of  the  Xile  thought  the 

«. 

actions  of  these  Insects,  when  rolling  their  balls,  were  typical  of 
the  planetary  and  lunar  revolutions :  and  that  the  sudden 
appearance  of  the  beetles  after  a  period  of  complete  absence  was 
emblematic  of  a  future  life.  Many  accounts  have  been  o-iven 

c. 

of  the  habits  of  members  of  this  group,  but  according  to  Fabre 
all  are  more  or  less  erroneous ;  and  he  has  described  the  habits 
and  life-history  of  Scarabaeus  sacer  (Fig.  89),  as  observed  by  him 
in  Southern  France.  These  Insects  act  the  part  of  scavengers  by 
breaking  up  and  burying  the  droppings  of  cattle  and  other 
animals.  The  female  Xcarabaeus  detaches  a  portion  of  the  dung 
and  forms  it  iiito  a  ball,  sometimes  as  large  as  the  fist :  this  it 
rolls  along  by  means  of  its  hind  legs,  by  pushing  when  necessary 
with  its  broad  head,  or  by  walking  backwards  and  dragging  the 
ball  with  its  front  legs.  The  strength  and  patience  displayed  by 
the  creature  in  the  execution  of  this  task  are  admirable.  Fre- 
quently the  owner  of  this  small  spherical  property  is  joined,  so 
Fabre  informs  us,  by  a  friend,  who  is  usually  of  the  same  sex  and 
assists  her  in  pushing  along  the  ball  till  a  suitable  place  is  reached. 
AVhen  this  is  attained,  the  owner  commences  to  excavate  a  chamber 
for  the  reception  of  the  ball ;  sometimes  the  false  friend  takes  ad- 
vantage of  the  opportunity  thus  offered  and  carries  off  the  ball 
for  her  own  use.  Should  no  disappointment  of  this  sort  occur,  the 
Scarabaeus  accomplishes  the  burying  of  the  ball  in  its  subterranean 
chamber,  and  accompanies  it  for  the  purpose  of  devouring  it ;  the 
feast  is  continued  without  intermission  till  the  food  is  entirely 


LAMELLICORNIA COPRIDES 


197 


exhausted,  when  the  *SV"/v//V/< //.<  .-^eks  a  fresh  store  of  provender 
u>  lie  treated  in  a  similar  manner.  According  to  M.  Fabre's 
account  these  events  occur  in  the  spring  of  the  year,  and  when 
the  hot  weather  sets  in  the  ,SVv//w/,</<  //.;•  passes  through  a  period  of 
quiescence,  emerging  again  in  the  autumn  to  recommence  its 
labours,  which  are  now,  however,  directed  immediately  to  the  con- 
tinuance of  the  species  :  a  larger  subterranean  chamber  is  formed. 
and  to  this  retreat  the  beetle  carries  dung  till  it  has  accumulated 
a  mass  of  the  size  of  a 
moderate  apple ;  this  mate- 
rial is  carefully  arranged, 
previous  to  the  laying 
of  the  egg,  in  such  a 
manner  that  the  grub  to 
be  hatched  from  the  egg 
shall  find  the  softest  and 
most  nutritive  portions 
close  to  it,  while  the 
d>arser  and  more  innu- 
tritions parts  are  arranged 
-  ts  to  be  reached  by  the 
grub  only  after  it  has 
acquired  some  strength  ; 
lastly,  a  still  more  deli- 
cate and  nutritive  paste 
is  prepared  by  the  mother 
tie  for  a  first  meal  for 
the  newly -hatched  grub, 
by  some  of  the  food  being 
submitted  to  a  partial  digestion  in  her  organs ;  finally,  the  -  _  _ 
is  deposited  in  the  selected  spot,  and  the  chamber  closed.  Certain 
of  the  Coprides  exhibit,  according  to  Fabre,  some  extremely 
exceptional  features  in  their  life-histories.  The  mother,  instead 
of  dying  after  opposition,  survives,  and  sees  the  growth  of  her 
vnung  to  the  perfect  state,  and  then  produces  another  generation. 
Xo  similar  case  can  be  pointed  out  in  Insects,  except  in  the  Social 
kinds:  but  from  these  the  Coprides  observed  by  Fabiv  differ  pro- 
foundly, inasmuch  as  the  number  of  eggs  produced  by  the  mother 
i-  extremely  small;  Copris  hispanus,  for  instance,  producing  in 
eaeh  of  its  acts  of  oviposition  only  one.  two,  or  three  __- 


FIG.  89. — Scambaeu-s  sneer.     Portueal. 


COLEOPTERA  CHAP. 


ii.  The  MELOLONTHIDES  are  probably  almost  as  numerous  as  the 
Coprides,  some  4000  species  being  already  known.  The  larvae 
are  believed  to  feed  chiefly  on  roots.  Melolontha  vulgar  is,  the 
common  cockchafer,  is  very  abundant  in  some  parts  of  Europe, 
and  owing  to  this  and  to  the  great  damage  it  causes,  has  attracted 
much  attention.  The  memoir  by  Straus-Durckheim  l  on  its 
anatomy  is  one  of  the  classical  works  of  Entomology.  This  In- 
sect is  so  injurious  in  some  parts  of  France  that  money  is  paid 
by  the  local  authorities  for  its  destruction.  M.  Eeiset  informs 
us  that  under  this  arrangement  867,173,000  perfect  cockchafers, 
and  647,000,000  larvae  were  destroyed  in  the  Seine-inferieure 
in  the  four  years  from  the  middle  of  1866  to  1870.  Unlike 
the  Coprides,  the  larval  life  in  Melolonthides  is  prolonged,  and 
that  of  the  imago  is  of  brief  duration.  In  Central  Europe  the 
life-cycle  of  the  individual  in  M.  r//A/"/'/x  occupies  three  years, 
though  in  dry  periods  it  may  be  extended  to  four  years.  In 
Scandinavia  the  time  occupied  by  the  development  appears  to  be 
usually  five  years.  The  fertile  female  enters  the  ground  and 
deposits  its  eggs  in  two  or  three  successive  batches  of  about 
fifteen  each.  The  eggs  swell  as  the  development  of  the  embryo 
progresses  ;  the  larva  emerges  about  five  weeks  after  the  eggs 
have  been  deposited,  and  is  of  relatively  large  size.  When 
young  the  larvae  can  straighten  themselves  out  and  crawl,  but 
when  older  they  lose  this  power,  and  when  above  ground  rest 
helplessly  on  their  sides.  In  the  winter  they  descend  deeply 
into  the  earth  to  protect  themselves  from  frost.  The  pupa 
state  lasts  only  a  few  days,  but  after  the  final  transformation  the 
perfect  Insect  may  remain  motionless  for  as  much  as  eight 
months  underground  before  commencing  its  active  life  in  the  air.2 
In  the  perfect  state  the  Insect  is  sometimes  injurious  from  the 
large  quantity  of  foliage  it  destroys.  Schiodte  3  considered  that 
these  larvae  (and  those  of  numerous  other  Scarabaeidae)  stridu- 
late  by  rubbing  certain  projections  on  the  stipes  of  the  maxilla 
against  the  under-surface  of  the  mandible.  These  surfaces  appear, 
however,  but  little  adapted  for  the  purpose  of  producing  sound. 

iii.  The  EUTELIDES  number  about  1500  species  :  there  ;ire  many 


1  Considerations  y/^'/v/A's  .•>•///•  I'anatomie  comparde  des  animautc  articulds,  etc., 
Paris  1828,  4to.  xix.  and  435  pp.,  and  Atlas  of  ten  (xx.)  plates,  and  36  pp. 
-  Raspail.  Me,  n.  SIK-.  zool.  France,  vi.  1893,  pp.  202-213. 
:l  Ann.  soc.  ent.  /''m/tce,  (v.)  iv.  1874.  p.  39. 


v  LAMELLICORNIA DYNASTIDES CETONIIDES  199 

Insects  of  brilliant  metallic  colours  amongst  them,  but  very  little 
is  known  as  to  their  life-histories.  The  larvae  are  very  much 
like  those  of  Melolonthides. 

iv.  The  DYNASTIDES  are  the  smallest  division  in  number  of 
species,  there  being  scarcely  1000  known ;  but  amongst  them 
we  find  in  the  genera  Dynastes  and  Megasoma  some  of  the 
bniM'st  of  existing  Insects.  The  horns  and  projections  on  the 
heads  and  prothoraces  of  some  of  the  males  of  these  Insects  are 
truly  extraordinary,  and  it  does  not  appear  possible  to  explain 
their  existence  by  any  use  they  are  to  their  possessors.  These 
structures  are  but  little  used  for  fighting.  Baron  von  Hiigel 
informs  the  writer  that  in  Java  he  has  observed  large  numbers 
of  Xylotrupes  gideon;  he  noticed  that  the  males  sometimes  carry 
the  females  by  the  aid  of  their  horns ;  but  this  must  be  an  excep- 
tional case,  for  the  shape  of  these  instruments,  in  the  majority  of 
Dynastides,  would  not  allow  of  their  being  put  to  this  use.  The 
development  of  these  horns  varies  greatly  in  most  of  the  species, 
but  he  did  not  find  that  the  females  exhibited  any  preference  for 
the  highly  armed  males.  The  fact  that  the  males  are  very  much 
larger  than  the  females,  and  that  the  armature  is  usually  confined 
to  them,  suggests,  however,  that  some  sexual  reason  exists  for  these 
remarkable  projections.  Many  Dynastides  possess  organs  of  stridu- 
lation,  consisting  of  lines  of  sculpture  placed  so  as  to  form  one  or 
two  bands  on  the  middle  of  the  propygidium,  and  brought  into 
play  by  being  rubbed  by  the  extremities  of  the  wing-cases.  This 
apparatus  is  of  a  less  perfect  nature  than  the  structures  for  the 
same  purpose  found  in  numerous  other  beetles.  "We  have  no 
member  of  this  sub-family  in  Britain,  and  there  are  scarcely  a 
dozen  in  all  Europe.  Decaying  vegetable  matter  is  believed  to 
be  the  nutriment  of  Dynastides.  The  European  Oryctes  nasicofnis 
is  sometimes  found  in  numbers  in  spent  tan.  The  growth  a::d 
development  of  the  individual  is  believed  to  be  but  slow. 

v.  The  CETONIIDES  are  renowned  for  the  beauty  of  their  colours 
and  the  elegance  of  their  forms;  hence  they  are  a  favourite 
group,  and  about  1600  species  have  been  catalogued.  They  ;nv 
specially  fond  of  warm  regions,  but  it  is  a  peculiarity  of  the 
sub-family  that  a  large  majority  of  the  species  are  found  in  the 
Old  World  ;  South  America  is  inexplicably  poor  in  these  Insects, 
notwithstanding  its  extensive  forests.  In  this  sub-family  the 
mode  of  night  is  peculiar  ;  the  elytra  do  not  extend  down  the 


20O  COLEOPTERA  CHAP. 

sides  of  the  body,  so  that,  if  they  are  elevated  a  little,  the  wings 
can  be  protruded.  This  is  the  mode  of  flight  adopted  by  most 
Cetoniides,  but  the  members  of  the  group  Trichiini  fly  in  the 
usual  manner.  In  Britain  we  have  only  four  kinds  of  Cetoniides  ; 
they  are  called  Kose-chafers.  The  larvae  of  C.fioricola  and  some 
other  species  live  in  ants'  nests  made  of  vegetable  refuse,  and  it 
is  said  that  they  eat  the  ants'  progeny.  Two  North  American 
species  of  Euphoria  have  similar  habits.  The  group  Cremasto- 
chilini  includes  numerous  peculiar  Insects  that  apparently  have 
still  closer  relations  with  ants.  Most  of  them  are  very  aberrant 
as  well  as  rare  forms,  and  it  has  been  several  times  observed  in 
N'nrth  America  that  species  of  Cremastochilus  not  only  live  in 
the  nests  of  the  ants,  but  are  forcibly  detained  therein  by  the 
owners,  who  clearly  derive  some  kind  of  satisfaction  from  the 
companionship  of  the  beetles.  The  species  of  the  genus  Lomap- 
ft'i-a  stridulate  in  a  peculiar  manner,  by  rubbing  the  edges  of  the 
hind  femora  over  a  striate  area  on  the  ventral  segments. 


Series  II.    Adephaga  or  Caraboidea. 

All  tli,-  tarsi  five-jointed ;  antennae  filiform,  or  nearly  so;  -mouth - 
l>iirf*  //////>///  ilcrelvpi'il,  flic  outer  lolie  of  tin'  nui.'-iUn  /n  <//•/// 
nl  inni/x  di ri<l <-<!  into  ii  I  ii-ti-jiiiiiti-il  pa/juts  ;  *//j>j>u,'ts  of  the 
liiliinl  palpi  il<  rt'liipnl  ^.s  joints  of  tlie  palpi,  and  in  so///' 
cases  approximate  at  their  bases.  Alxlunn n  n-itli  tin'  imposed 
*•  <j  me  nix  inn  more  in  number  at  the  sides  than  a/u//</  the 
in 'nl /lie,  the  number  Iciinj  nxnall/i  :fi re  along  the  midill<,  */./• 
nt  iifh  side.. 

THIS  extensive  series  includes  the  tiger-beetles,  ground-beetles, 
and  true  water -beetles ;  it  consists  of  six  families,  and  forms 
a  natural  assemblage.  It  is  sometimes  called  Garni vora  or 
Filicornia.  The  exceptions  to  the  characters  we  have  mentioned 
are  but  few.  The  supports  of  the  labial  palpi  are  frequently 
covered  by  the  mentum,  and  then  the  palpi  appear  three-jointed; 
but  when  the  joint-like  palpiger  is  not  covered  these  palps  appear 
four-jointed.  As  a  rule,  approximation  of  these  supports  is  indica- 
tive of  high  development.  In  some  of  the  lower  forms  the  trophi 
remain  at  a  lower  stage  of  development  than  is  usual.  This  is 
especially  the  case  with  the  genus  Amphizoa,  which  forms  of 


v  ADEPHAGA TIGER-BEETLES  2OI 

itself  the  family  Amphizoidae.  The  Bombardier-beetles  make  an 
exception  as  regards  the  abdominal  structure,  for  in  some  of  them 
no  less  than  eight  segments  are  visible,  either  along  the  middle 
line  or  at  the  sides  of  the  venter.  In  Hydroporides  (one  of  the 
divisions  of  Dytiscidae)  the  front  and  middle  feet  have  each  only 
four  joints.  Many  naturalists  unite  the  Gyrinidae  with  the 
Adephaga,  and  a  few  also  associate  with  them  the  Paussidae  and 
Ehyssodidae ;  but  we  think  it  better  at  present  to  exclude  all 
these,  though  we  believe  that  both  Paussidae  and  Rhyssodidae 
will  ultimately  "be  assigned  to  the  series.  The  larvae  are  usually 
very  active,  and  have  a  higher  development  of  the  legs  than  is 
usual  in  this  Order.  Their  tarsi  possess  two  claws. 

Fam.  4.  Cicindelidae  (Tiger -beetles).  —  Clypeus  extending 
laterally  in  front  of  the  insertion  of  the  antennae.  Lower  lip  with 
the  palpi  usually  yreatli/  developed,  but  with  the  liijula  and  pam- 
f/lossae  very  much  reduced,  often  .sr^/w///  to  be  detected.  M/i.i'illni' 
with  the  outer  lobe  form  in*/  a  tiro-jointed  palp}  the  inner  lobe 
elongate,  furnished  «t  the  tip  with  a  hook-like  process,  which  is 
usually  articulated  by  a  joint  //•////  f//c  lobe  itself.  The  tiger-beetles 
are  very  active  Insects,  running  with  extreme  speed,  and  some- 
times flying  in  a  similar  manner ;  they  are  all  predaceous,  and 
amongst  the  most  voracious  and  fierce  of  the  carnivorous  beetles, 
so  that  they  well  deserve  their  name.  Bates,  speaking  of  the 
Amazonian  Megacephala,  says  "  their  powers  of  running  exceed 
anything  I  have  ever  observed  in  this  style  of  Insect  locomotion  ; 
they  run  in  a  serpentine  course  over  the  smooth  sand,  and  when 
closely  pursued  by  the  hand  they  are  apt  to  turn  suddenly  back 
and  thus  baffle  the  most  practised  hand  and  eye."  He  further 
says  that  the  species  he  observed  (being  of  diverse  colours) 
a  "'reed  in  colour  with  the  general  colours  of  the  "  locale  thev 

O  ™  f1 

inhabit."  The  larvae  of  Cicindelidae  live  in  deep  burrows,  sink- 
ing more  or  less  vertically  into  the  ground,  and  in  these  they 
take  up  a  peculiar  position,  for  which  their  shape  is  specially 
adapted;  the  head  and  prothorax  are  broad,  the  rest  of  the  body 
slender,  the  fifth  segment  of  the  abdomen  is  furnished  on  the 
back  with  a  pair  of  strong  hooks ;  the  ocelli  on  the  sides  of  the 
head  are  very  perfect.  Supporting  itself  at  the  top  of  the  burrow 
by  means  of  these  hooks  and  of  its  terminal  tube,  the  larva  blocks 
the  mouth  of  the  burrow  with  its  large  head  and  prothorax,  and 

1  In  Theratides  this  outer  lobe  is  in  a  rudimentary  state,  like  a  seta. 


2O2 


COLEOPTERA 


CHAP. 


in  this  position  waits  for  its  prey.  This  consists  of  Insects  that 
may  alight  on  the  spot  or  run  over  it.  AVhen  an  Insect  ventures 
within  reach,  the  head  of  the  larva  is  thrown  back  with  a  rapid 
jerk,  the  prey  is  seized  by  the  long  sharp  mandibles,  dragged  to 
the  bottom  of  the  burrow  and  devoured.  The  burrows  are  often 
more  than  a  foot  deep,  and  are  said  to  lie  excavated  by  the  larva 
itself,  which  carries  up  the  earth  on  the  shovel-like  upper  surface 
of  its  head.  The  female  tiger-beetle  is  endowed  with  powerful 
and  elongate  excavating  instruments  at  the  termination  of  the 
body,  and  it  is  probable  that  when  placing  the  egg  in  the  earth 

she  facilitates  the  future  opera- 
tions of  the  larva  by  forming 
the  outlines  of  the  burrow.  Ex- 
tremely few  larvae  of  Cicin- 
delidae  are  known,  but  they  all 
exhibit  the  type  of  structure 
mentioned  above,  and  apparently 
have  similar  habits.  Our  little 
British  Cicindd«,  most  of  which 
are  so  active  on  the  wing,  agree 
in  these  respects  with  the  African 
species  of  Jbnificora,  which  are 
entirely  apterous,  and  are  the 
largest  of  the  Cicindelid.ie.  Per- 

Fio.    90.  —  (Jicindela    hybrida.     Britain. 

A,  larva  (after  Schiodte) ;  B,  imago,  inguey  found  a  breeding-ground 

of  M,  tultci'culata  near  Kimberley  ; 

the  larvae  were  living  in  the  usual  Cicindelid  manner:  but  the 
ground  was  so  hard  that  he  was  not  able  to  investigate  the 
burrows,  and  there  were  but  few  Insects  that  could  serve  as  food 
in  the  neighbourhood. 

The  Ciciudelidae,  although  one  of  the  smaller  families  of  Cole- 
optera,  now  number  about  1400  species;  of  these  about  one-half 
belong  to  the  great  genus  Cicindela,  to  which  our  four  British 
representatives  of  the  Cicindelidae  are  all  assigned.  There  is  no 
general  work  of  much  consequence  on  this  important  family,  and 
its  classification  is  not  thoroughly  established.1 

Tiger-beetles  display  considerable  variety  of  structure,  especially 
iis  regiirds  the  mouth,  which  exhibits  very  remarkable  develop- 

1  Tin-  first   portion   of  a    classification    of  (.'icindrliiUe   by   Dr.    "\Valther  Horn, 
J'i'i-isi"n  ili' i'  Cicindeliden,  Berlin,  1898,  lias  appeared  since  this  was  written. 


CICINDELIDAE TIGER-BEETLES 


203 


iin'iits  of  the  palpi  and  labrum  (Fig.  91).  The  tiger-beetles, 
like  most  other  Insects  that  capture  living  prey,  do  not  consume 
their  victims  entire,  but  subsist  chiefly  on  the  juices  they 
squeeze  out  of  them ;  the  hard  and  innutritions  parts  are  rejected 
after  the  victim  has  been  thoroughly  lacerated  and  squeezed:  the 
mouth  forms  both  trap  and 
press ;  the  palpi  spread  out 
in  order  to  facilitate  the 
rapid  engulfing  of  a  victim, 
then  close  up  under  it  and 
help  to  support  it  in  the 
mouth  ;  while  the  labrum 
above  closes  the  cavity  in 
the  other  direction.  The 
mouth  itself  is  a  large  cavity 
communicating  very  freely 
with  the  exterior,  but  so 
completely  shut  off  from  the 
following  parts  of  the  ali- 
mentary canal  that  it  is 
difficult  to  find  the  orifice  of 
communication  ;  the  labium 


FIG.  91.  —  Mouth  -  parts  of  tiger  -  beetles.  A. 
Profile  of  Po0Wios£o»!ffl  sp.  (Madagascar)  :  a, 
antenna  ;  b,  labial  palp  ;  c,  maxillary  palp  ; 
d,  palpifonn  lobe  of  maxilla  ;  e,  mandible  ;  /. 
labrum.  B,  Section  of  head  of  Manticora, 


heing 


(South  Africa)  :  a,  front  of  upper 
part  of  head-capsule  ;  b,  gula  ;  c,  teutorium  ; 
(/,  eye  ;  e,  labrum  ;  /,  left  mandible  ;  g,  max- 
illa ;  /;,  maxillary  palp  ;  i,  labial  palp  ;  f,; 
support  of  this  palp  ;  /,  labium. 


much  modified  to 
form  the  posterior  wall. 
For  the  capture  of  the  prey, 
always  living  but  of  various 
kinds,  a  mechanism  with  great  holding  power  and  capable  of 
rapid  action  is  required.  The  mouth  of  the  terrestrial  Manticora 
(Fig.  91,  B),  exhibits  great  strength  ;  some  of  the  chitinous  parts 
are  extremely  thick,  the  mandibles  are  enormous,  the  palpi,  how- 
ever, are  comparatively  low  in  development.  In  the  arboreal 
genus  Pogonostoma  the  palpary  structures  (Fig.  91,  A)  attain  a 
development  scarcely  equalled  elsewhere  in  the  Insect  world.  The 
great  majority  of  the  Cicindelidae  are  inhabitants  of  the  warmer, 
or  of  the  tropical  regions  of  the  world,  and  very  little  is  known  as 
to  their  life-histories  ;  they  show  great  diversity  in  their  modes 
of  hunting  their  prey.  Some  are  wingless  ;  others  are  active  on 
the  wing ;  and  of  both  of  these  divisions  there  are  forms  that  are 
found  only  on  trees  or  bushes.  Some,  it  is  believed,  frequent 
onlv  the  mounds  of  Termites.  The  characteristic  feature  common 


204 


COLEOPTERA 


CHAl'. 


to  all  is  great  activity  and  excessive  wariness.  The  genus 
Pogonostoma,  to  which  we  have  already  alluded,  is  confined  to 
Madagascar,  where  the  species  are  numerous,  but  are  rare  in 
collections  on  account  of  the  difficulty  of  securing  them.  Eaffray 
informs  us  that  certain  species  frequent  the  trunks  of  trees,  up 
which  they  run  in  a  spiral  manner  on  the  least  alarm.  The  only 
way  he  could  obtain  specimens  was  by  the  aid  of  an  assistant ; 
the  two  approached  a  tree  very  quietly  from  opposite  sides,  and 
when  near  it,  made  a  rush,  and  joined  hands  as  high  up  the 
trunk  as  they  could,  so  as  to  embrace  the  tree,  when  the  Pogonos- 
toma fell  to  the  ground  and  was  captured. 

Fam.  5.  Carabidae  (Ground-beetles). — Clypeus  not  extending 
lateral///  in  front  of  the  antennae.  Maxillae  iritli  the  outer  lobe 
destitute  of  an  articulated  hook  at  the  ///<.  Antennae  covered 
(except  tin'  band  joints}  with  a  minute  pubescence.  Hind  legs  not 
very  different  from  the  middle  pair,  formed  for  running,  as  ttst/al 
in  beef  fry.  This  is  one  of  the  largest  and  most  important  of  the 

families  of  Coleoptera,  in- 
cluding as  it  does  12,000 
or  13,000  described 
species.  In  this  country 
( 'a  ra  b  idae  are  nearly 
entirely  terrestrial  in 
habits,  and  are  scarcely 
ever  seen  on  the  wing : 
many  of  the  species  indeed 
have  merely  rudimentary 
wings ;  in  the  tropics 
there  are,  however,  many 
arboreal  forms  that  take 
wing  with  more  or  less 
alertness.  The  larvae  (Fig. 
(.>2,  A)  are  usually  elon- 
gate in  form  and  run 
freely  :  they  may  be  known 
by  their  tarsi  ending  in  two  claws,  by  the  exserted,  sharp,  calliper- 
like  mandibles,  by  the  body  ending  in  two  processes  (sometimes 
jointed)  and  a  tube  of  varying  length  projecting  backwards. 
The  pupae  usually  have  the  hind  pair  of  legs  so  arranged  that 
the  tips  of  the  tarsi  project  behind,  beyond  the  extremity  of  the 


Sdiiodte)  ;  B,  imago. 


A,  Larva  (after 
Britain. 


v  ADEPHAGA CARABIDAE  2O5 

body.  The  Carabidae  are  carnivorous  and  predaceous  both  as 
larvae  and  perfect  Insects  ;  they  attack  living  Insects,  worms,  or 
other  small,  soft  creatures,  but  do  not  disdain  dead  specimens. 
Some  species  of  Carabus,  found  in  North  Africa  where  snails 
abound,  are  specially  formed  for  attacking  these  molluscs,  having 
the  head  long  and  slender  so  that  it  can  be  thrust  into  the  shell 
of  the  snail.  A  few  species  have  been  detected  eating  growing  corn, 
and  even  the  young  seeds  of  some  Umbelliferae  ;  these  belong  chiefly 
to  the  genera  Harpalus,  Zabrus,  and  Amara.  Some  species  of  the 
abundant  genera  Pterostichus  and  Harpalus,  are  said  to  be  fond  of 
ripe  strawberries.  The  most  anomalous  forms  of  Carabidae  are  the 
Pseudomorpliides,  a  sub-family  almost  peculiar  to  Australia,  the 
members  of  which  live  under  bark,  and  have  but  little  resemblance 
to  other  Carabids  owing  to  their  compact  forms  and  continuous 
outlines.  The  genus  Mormolyce  is  one  of  the  wonders  of  the  Insect 
world  on  account  of  the  extraordinary  shape  of  its  members ;  the 
sides  of  the  elytra  form  large  crinkled  expansions,  and  the  head 
is  unusually  elongate.  These  Insects  live  on  the  underside  of 
fallen  trees  in  the  Malay  Archipelago  and  Peninsula ;  no  reason 
whatever  can  be  at  present  assigned  for  their  remarkable  shape. 

There  are  a  considerable  number  of  blind  members  of  this 
family  :  some  of  them  live  in  caverns ;  these  belong  chiefly  to 
the  genus  Anophthcdmus,  species  of  which  have  been  detected  in 
the  caves  of  the  Pyrenees,  of  Austria,  and  of  North  America. 
It  has  been  shown  that  the  optic  nerves  and  lobes,  as  well  as  tin- 
external  organs  of  vision,  are  entirely  wanting  in  some  of  these 
cave  Carabidae  ;  the  tactile  setae  have,  however,  a  larger  develop- 
ment than  usual,  and  the  Insects  are  as  skilful  in  running  as  if 
they  possessed  eyes.  Anophthalmus  is  closely  related  to  our 
British  genus  Trechvs,  the  species  of  which  are  very  much  given 
to  living  in  deep  crevices  in  the  earth,  or  under  large  stones,  and 
have  some  of  them  very  small  eyes.  In  addition  to  these 
cavernicolous  Anophthalmus,  other  blind  Carabidae  have  been 
discovered  during  recent  years  in  various  parts  of  the  world, 
where  they  live  under  great  stones  deeply  embedded  in  the 
earth :  these  blind  lapidicolous  Carabidae  are  of  extremely 
minute  size  and  of  most  sluggish  habits ;  the  situations  in 
which  they  are  found  suggest  that  many  successive  generations 
are  probably  passed  under  the  same  stone.  Not  a  single 
specimen  has  ever  been  found  above  ground.  The  minute 


206  COLEOPTERA 


CHAP. 


Carabids  of  the  genus  ACJIKS,  that  pass  a  large  part  of  their 
lives  under  stones  below  high-water  mark  (emerging  only  when 
the  tide  uncovers  them),  on  the  borders  of  the  English  Channel 
and  elsewhere,  are  very  closely  allied  to  these  blind  Insects,  and 
have  themselves  only  very  small  eyes,  which,  moreover,  according 
to  Hammond  and  Miall,  are  covered  in  larger  part  by  a  peculiar 
shield.1  A  few  Carabidae,  of  the  genera  6V///>/V.s  and  Orthogonius, 
are  believed  to  live  in  the  nests  of  Termites.  Savage  found  the 
larva  of  G.  sculptilis  in  the  nests  of  Tcrmes  IcHicosus;  it  has 
been  described  by  Horn,  and  is  said  to  bear  so  great  a  resem- 
blance to  young  queens  of  the  Termites  as  to  have  been  mistaken 
for  them.2  Mr.  Haviland  found  Rhopalomelus  angusticoUis  in 
Termites'  nests  in  South  Africa.  Peringuey  states  that  it  emits 
a  very  strong  and  disagreeable  odour.  It  is  probable  that  it 
preys  on  the  Termites,  and  this  also  is  believed  to  be  the  habit 
of  the  Ceylonese  Hdluodes  taprobanae.  Some  species  of  the 
Mediterranean  genus  Siagona  stridulate  by  means  of  a  file  on 
the  under  surface  of  the  prothorax,  rubbed  by  a  striate  area, 
adapted  in  form,  on  the  anterior  femora. 

A  valuable  memoir  on  the  classification  of  this  important 
family  is  due  to  the  late  Dr.  (I.  H.  Horn  ;  3  he  arranges  Carabidae 
in  three  sub-families  ;  we  think  it  necessary  to  add  a  fourth  for 


1.  Middle  coxal  cavities  enclosed  externally  by  the  junction  of  the  nieso-  and 

nieta-sternum  ;    neither   epimeron   nor   episternum    attaining    tin- 

cavity. 
Head   beneath,   "with    a  deep    groove  on   each    side    near    the    eye    for 

the  reception  of  the  antennae  or  a  part  thereof. 

Sub-fam.  3.  PSEUDOMORPHIDES. 
Head  without  antennal  grooves.  Sub-fam.   2.  HARPALIDES. 

2.  Middle  coxal  cavities  attained  on  the  outside  by  the  tips  of  the  episterna 

and  epimera.  Sub-fam.  4.  MORMOLYCIDES. 

3.  Middle  coxal  cavities  attained  on  the  outside  by  the  tips  of  the  epinirm, 

but  not  by  those  of  the  episterna.  Sub-fain.    1.  CARABIDES. 

These  four  sub-families  are  of  extremely  different  extent  and 
nature.  The  Harpalides  are  the  dominant  forms,  and  include 
upwards  of  10,000  known  species;  while  the  various  tribes 
into  which  the  sub-family  is  divided  include,  as  a  rule,  each  many 


i/  of  aquatic  Insects,  1895,  p.  376. 
2  Tr.  Anur.  cnt.  Soc.  xv.  1888,  p.  18. 
<>j>.  cit.  v.  1881,  p.  91  ;  cf.  Sharp,  Tr.  cut.  Soc.  London,  1S82,  p.  61. 


ADEPHAGA AMPHIZOIDAE PELOBIIDAE 


207 


genera  ;  the  Carabides  are  next  in  importance,  with  upwards  of 
2000  species,  but  are  divided  into  a  comparatively  large  number  of 
tribes,  each  of  which  averages  a  much  smaller  number  of  genera 
than  do  the  tribes  of  Harpalides ;  Pseudomorphides  includes  only 
about  100  species ;  and  Mormolycides  consists  of  the  single  genus 
Mormolycc  with  three  species. 

Fam.  6.  Amphizoidae. — Antennae  destitute  of  pubescence  : 
outer  lobe  of  maxilla  not  jointed;  metasternum  with  a  short 
transverse  impressed  line  on  the  middle  behind.  Hind  legs  slender, 
not  formed  for  swimming.  This  family  is  limited  to  the  genus 
Ampliizoa ;  the  species  of 
which  may  be  briefly  de- 
scribed as  lowly  organised 
Carabidae  that  lead  an 
aquatic  life.  The  geo- 
graphical distribution  is 
highly  remarkable,  there 
being  but  three  species,  two 
of  which  live  in  Western 
Itforth  America,  the  third 
in  Eastern  Tibet.  The 
habits  of  American  Am- 
phizoa  are  known  ;  they  pass 
a  life  of  little  activity  in 
very  cold,  rapid  streams ; 

FIG.  93. — Amphizoa  lecontei.      North  America, 
they      do      not      SWllll,       but  A,  Larva  ;  B,  imago. 

cling  to  stones  and   timber. 

The  larva  was  recently  discovered  in  Utah  by  Messrs.  Hubbard 
and  Schwarz : :  it  has  the  same  habits  as  the  perfect  Insect, 
and  in  general  form  resembles  the  larvae  of  the  genus  Cardbus ; 
but  it  has  no  terminal  tube  to  the  body,  the  abdomen  consisting 
of  eight  segments  and  a  pair  of  short  terminal  appendages ;  the 
spiracles  are  obsolete,  with  the  exception  of  a  pair  placed  near  to 
one  another  at  the  termination  of  the  eighth  abdominal  segment. 
As  regards  the  mouth  this  larva  is  Carabid,  as  regards  the 
abdomen  and  stigmata  Dytiscid  of  a  primitive  type. 

Fam.  7.  Pelobiidae. — Antennae  destitute  of  pubescence  :  outer 
lobe  of  maxilla  jointed,  metasternum  with  a  short  transverse 
impressed  line  on  the  middle  behind.  Hind  legs  rather  slender, 

1  P.  ent.  Soc.   Washington,  ii.  1892,  p.  341. 


208 


COLEOPTERA 


CHAP. 


formed  for  swimming,  the  tarsi  longer  tlt/m  lite  tililae.  This  family 
is  limited  to  the  one  genus  Pelolnus  (Hygrolna  of  some  authors). 
Like  Ani]i}ii~oa,  to  which  it  is  in  several  respects  analogous,  it 
lias  a  singular  geographical  distribution ;  there  are  only  four 
known  species,  one  lives  in  Britain  and  the  Mediterranean  region, 
one  in  Chinese  Tibet,  two  in  Australia,  Pelobivs  may  be  briefly 

t/  *' 

described    as   a    Carabid    adapted    to    a    considerable    extent    for 
living    in    and   swimming    about    in   water ;  differing   thus  from 


FIG.  94. — Pelobius  tardus.      Britain.      A,  Young  larva  ;  B,  adult  larva  ;  C,  imago. 

(A  ami  B  alter  Scliiodte.) 

Amphizoa,  which  has  no  special  adaptation  for  swimming.  The 
larva  of  Pelobius  is  remarkable ;  it  breathes  by  means  of  1  iranchial 
filaments  on  the  under  surface  of  the  body,  the  spiracles  being 
present,  though  those  of  the  abdomen  are  very  minute  and  the 
others  small.  The  head  is  very  large,  the  mandibles  are  not 
tube-like,  the  food  being  taken  after  the  manner  of  the  Carabidae  ; 
the  8th  abdominal  segment  ends  in  three  long  processes ;  the 
small  9th  segment  is  retracted  beneath  them.  The  adult  7V/W^Vs 
inriliix  is  remarkable  for  its  loud  stridulation.  The  sound  is  pro- 
duced by  an  apparatus  described  correctly  by  Charles  Darwin:1 

1  Descent  of  Mi  in,,  i.  1890,   p.  338;  The  views  of  Landois  aud  Recker,  Arch.  f. 
Naturgesch.  Ivii.  1,  1891,  p.  101,  are  erroneous. 


V 


ADEPHAGA HALIPLIDAE 


209 


there  is  a  file  on  the  inside  of  the  wing-cases,  and  the  Insect 
turns  up  the  tip  of  the  abdomen  and  scrapes  the  tile  therewith. 
The  Insects  are  called  squeakers  in  the  Covent  Garden  market, 
where  they  are  sold. 

Fam.  8.  Haliplidae. — Antennae  hire,  ten  -  jointed  ;  meta- 
sternum  marked  l>y  a  transverse  line;  posterior  coxae  'prolonged 
as  plates,  covering  a,  large 
part  of  the  lower  surface 
of  the  abdomen ;  the 
slender,  hut  clubbed,  hind 
femora  move  between  these 
plates  and  the  abdomen. 
The  Haliplidae  are 
aquatic,  and  are  all  small, 
not  exceeding  four  or  five 
millimetres  in  length. 
The  ventral  plates  are 
peculiar  to  the  Insects  of 
this  family,  but  their  func- 
tion is  not  known.  The 
larvae  are  remarkable  on 
account  of  the  fleshy  pro- 
cesses disposed  on  their 
bodies ;  but  they  exhibit 
considerable  variety  in 
this  respect ;  their  man- 
dibles are  grooved  so  that 
they  suck  their  prey.  In 
the  larva  of  Haliplus, 
according  to  Schiodte, 
there  are  eight  pairs  of 
abdominal  spiracles,  but 
in  Cnemidotus  (Fig.  95, 

-r,N    , -,  ,          FIG.  95. — Cnemidotus  caesus.     England.    A,  Imago  ; 

B),  there  are   110   spiracles,          B,  larva,  highly  magnified.     (After  Schiodte.) 

and    air    is    obtained    by 

means  of  a  trachea  traversing  each  of  the  long  filaments.  The 
Insects  of  these  two  genera  are  so  similar  in  the  imaginal  instar 
that  it  is  well  worthy  of  note  that  their  larvae  should  be  distin- 
guished by  such  important  characters.  Haliplidae  is  a  small 
family  consisting  of  three  genera,  having  about  100  species; 

VOL.   VI  P 


210 


COLEOPTERA 


CHAP. 


it  is  very  widely  distributed.      We   have  13  species   in  Britain, 
all  the  genera  being  represented. 

Fam.  9.  Dytiscidae  (Water-beetles). — Antennae  bare;  hind 
legs  formed  for  sunmming,  not  capable  of  ordinary  walking  :  nieta- 
sternum  without  a-  transverse  line  across  it ;  behind  closely  united 
with  the  extremely  large  coxae.  Outer  lobe  of  maxilla  forming  a 
two-jointed  palpus. '  The  Dytiscidae,  or  true  water-beetles,  are  of 
interest  because — unlike  the  aquatic  Neuroptera — they  exist  in 

water  in  both  the 
larval  and  imaginal 
instars  ;  nevertheless 
there  is  reason  for  sup- 
posing that  they  are 
modified  terrestrial 
Insects :  these  reasons 
are  (1)  that  in  their 
general  organisation 
they  are  similar  to 
the  Carabidae,  and 
they  drown  more 
quickly  than  the 
majority  of  land 
beetles  do  ;  (2)  though 
the  larvae  are  very 
different  from  the 
larvae  of  terrestrial 
beetles,  yet  the  ima- 
ginal instars  are  much 
less  profoundly 
changed,  and  are  capable  of  existing  perfectly  wrell  on  land,  and 
of  taking  prolonged  nights  through  the  air  ;  (3)  the  pupa  is,  so 
far  as  known,  always  terrestrial.  The  larvae  and  images  are 
perfectly  at  home  in  the  water,  except  that  they  must  come  to 
the  surface  to  get  air.  Some  of  them  are  capable,  however,  when 
quiescent,  of  living  for  hours  together  beneath  the  water,  but 
there  appears  to  be  great  diversity  in  this  respect.1  The  hind 
pair  of  legs  is  the  chief  means  of  locomotion.  These  swiinming- 
legs  (Fig.  97)  are  deserving  of  admiration  on  account  of  their 
mechanical  perfection ;  this,  however,  is  exhibited  in  various 

1  Src  J.  Linn.  Soc.  Zool.  xiii.  1876,  p.  161. 


A 


FIG.  96. — Cybister  roesdi  (  =  laterima,rginalis  De  G.) 
Europe.     A,  Larva  (after  Sclriudte)  ;  B,  <J  imago. 


ADEPHAGA — WATER-BEETLES 


2  I  I 


B 


degrees,  the  legs  in  the  genera  Dytiscus  and  Hydroporus  being 
but  slender,  while  those  of  Cybister  are  so  broad  and  powerful,  that 
a  single  stroke  propels  the  Insect  for  a  considerable  distance. 

The  wing-cases  fit  perfectly  to  the  body,  except  at  the  tip,  so 
as  to  form  an  air-tight  space  between  themselves  and  the  back  of 
the  Insect ;  this  space  is  utilised  as  a  reservoir  for  air.  When 
the  Dytiscus  feels  the  necessity  for  air  it  rises  to  the  surface  and 
exposes  the  tip  of  the  body  exactly  at  the  level  of  the  water, 
separating  at  the  same  time  the  abdomen  from  the  wing-cases 
so  as  to  open  a  broad  chink  at  the  spot  where  the  parts  were, 
during  the  Insect's  submersion,  so  well  held  together  as  to  be  air- 
and  water  -  tight.  The  ter- 
minal two  pairs  of  spiracles 
are  much  enlarged,  and  by 
curving  the  abdomen  the 
beetle  brings  them  into  con- 
tact with  the  atmosphere ; 
respiration  is  effected  by  this 
means  as  well  as  by  the  store 
of  air  carried  about  under  the 
wing  -  cases.  The  air  that 
enters  the  space  between  the 
elytra  and  body  is  shut  in 
there  when  the  Insect  closes 
the  chink  and  again  dives  beneath  the  water.  The  enlargement 
of  the  terminal  stigmata  in  Dytiscus  is  exceptional,  and  in  forms 
more  highly  organised  in  other  respects,  such  as  Cybister,  these 
spiracles  remain  minute ;  the  presumption  being  that  in  this 
case  respiration  is  carried  011  almost  entirely  by  means  of  the 
•supply  the  Insect  carries  in  the  space  between  the  elytra  and  the 
base  of  the  abdomen.1  The  structure  of  the  front  foot  of  the  male 
Dytiscus,  and  of  many  other  water-beetles,  is  highly  remarkable, 
the  foot  being  dilated  to  form  a  palette  or  saucer,  covered  beneath 
by  sucker-like  structures  of  great  delicacy  and  beauty ;  by  the  aid 
of  these  the  male  is  enabled  to  retain  a  position  on  the  female  for 
many  hours,  or  even  days,  together.  Lowne  has  shown  that  the 


' — Hind-  or  swimming-leg  of  Cybister 
A,  The  whole  leg  detached  ; 
B,  the  movable  parts  in  the  striking  posi- 
tion, a,  Coxa  ;  b,  trochanter  ;  c,  lemur  ; 
d,  tibia  ;  e,  last  joint  of  tarsus. 


1  For  many  particulars  as  to  respiration  of  Dytiscus,  and  peculiarities  of  the 
larva  see  Miall,  Aquatic  Insects,  1895,  pp.  39,  etc.  (In  the  figure  given  on  p.  (30 
the  large  stigma  on  the  terminal  segment  of  the  abdomen  is  omitted,  though  it  is 
referred  to  in  the  text.) 


2  1 2  COLEOPTERA  CHAP. 

suckers  communicate  with  a  sac  in  the  interior  of  the  foot  contain- 
ing fluid,  which  exudes  under  pressure.  As  the  portions  of  the 
skeleton  of  the  female  on  which  these  suckers  are  brought  to 
bear  is-  frequently  covered  with  pores,  or  minute  pits,  it  is  prob- 
able that  some  correlation  between  the  two  organisms  is  brought 
about  by  these  structures.  The  females  in  many  groups  of 
Dytiscidae  bear  on  the  upper  surface  of  the  body  a  peculiar 
sculpture  of  various  kinds,  the  exact  use  of  which  is  unknown ; 
in  many  species  there  are  two  forms  of  the  female,  one  possessing 
this  peculiar  sculpture,  the  other  nearly,  or  quite,  without  it. 
The  larvae  of  Dytiscidae  differ  from  those  of  Carabidae  chiefly 
by  the  structure  of  the  mouth  and  of  the  abdomen.  They  are 
excessively  rapacious,  and  are  indeed  almost  constantly  engaged 
in  sucking  the  juices  of  soft  and  small  aquatic  animals,  by  no 
means  excluding  their  own  kind.  The  mode  of  suction  is  not 
thoroughly  known,  but  so  far  as  the  details  have  been  ascertained 
they  are  correctly  described,  in  the  work  on  aquatic  Insects,  by 
Professor  Miall,  we  have  previously  referred  to ;  the  mandibles 
are  hollow,  with  a  hole  near  the  tip  and  another  at  the  base,  and 
being  sharp  at  the  tips  are  thrust  into  the  body  of  a  victim,  and 
then  by  their  closure  the  other  parts  of  the  mouth,  which  are 
very  beautifully  constructed  for  the  purpose,  are  brought  into 
fitting  mechanical  positions  for  completing  the  work  of  emptying 
the  victim.  Nagel  states  that  the  larva  of  Dytiscus  injects  a 
digestive  fluid  into  the  body  of  its  victim,  and  that  this  fluid 
rapidly  dissolves  all  the  more  solid  parts  of  the  prey,  so  that  the 
rapacious  larva  can  easily  absorb  all  its  victim  except  the 
insoluble  outer  skin.  The  abdomen  consists  of  only  eight 
segments,  and  a  pair  of  terminal  processes ;  the  stigmata  are  all 
more  or  less  completely  obsolete — according  to  species — with  the 
exception  of  the  pair  on  the  eighth  segment  at  the  tip  of  the 
body ;  the  terminal  segments  are  frequently  fringed  with  hairs, 
that  serve  not  only  as  means  of  locomotion,  but  also  to  float  the 
pair  of  active  stigmata  at  the  surface  when  the  creature  rises  to 
get  air.  Although  the  larvae  of  Dytiscidae  are  but  little  known, 
yet  considerable  diversity  has  already  been  found.  Those  of 
Hyphydrus  and  some  species  of  Hydroporus  have  the  front  of  the 
head  produced  into  a  horn,  which  is  touched  by  the  tips  of  the 
mandibles. 

Dytiscidae  are  peculiar  inasmuch  as  they  appear  to  flourish 


v       POLYMORPHA CLAVICORNS,  SERRICORNS,  ETC.    2  I  3 

Lest  in  the  cooler  waters  of  the  earth.  Lapland  is  one  of  the 
parts  of  Europe  richest  in  Dytiscidae,  and  the  profusion  of  species 
in  the  tropics  compared  with  those  of  Europe  is  not  nearly  so 
great  as  it  is  in  the  case  of  most  of  the  other  families  of 
Coleoptera.  About  1800  species  are  at  present  known,  and  we 
have  rather  more  than  100  species  in  Britain.1 

Series  III.   Polymorpha. 

Ante'nnae  frequently  either  thicker  at  the  tip  (clavicorn)  or  serrate 
along  their  inner  edge  (serricorn) ;  but  these  characters,  as 
well  as  the  number  of  joints  in  the  feet  and  oilier  points,  are 
very  variable. 

Upwards  of  fifty  families  are  placed  in  this  series  ;  many  of 
these  families  are  of  very  small  extent,  consisting  of  only  a  few 
species ;  other  families  of  the  series  are  much  larger,  so 
that  altogether  about  40,000  species — speaking  broadly,  about 
one-fourth  of  the  Coleoptera — are  included  in  the  series.  We 
have  already  (p.  189)  alluded  to  the  fact  that  it  is  formed  by 
certain  conventional  series,  Clavicornia,  Serricornia,  etc,  united, 
because  it  has  hitherto  proved  impossible  to  define  them. 

Fam.  10.  Paussidae. — Antennae  of  extraordinary  form, usually 
two-jointed,  sometimes  six-  or  ten-jointed.  Elytra  elongate,  but  trun- 
cate behind,  leaving  the  pygidium  exposed.  Tarsi  five-jointed.  The 
Paussidae  have  always  been  recognised  as  amongst  the  most 
remarkable  of  beetles,  although  they  are  of  small  size,  the  largest 
attaining  scarcely  half  an  inch  in  length.  They  are  found  only 
in  two  ways ;  either  in  ants'  nests,  or  on  the  wing  at  night. 
They  apparently  live  exclusively  in  ants'  nests,  but  migrate 
much.  Paussidae  usually  live  in  the  nests  of  terrestrial  ants,  but 
they  have  been  found  in  nests  of  Cremastogaster  in  the  spines  of 
Acacia  fistulosa.  They  have  the  power  of  discharging,  in  an 
explosive  manner,  a  volatile  caustic  fluid  from  the  anus,  which  is 
said  by  Loinan  to  contain  free  iodine.  Their  relations  to  the 
ants  are  at  present  unexplained,  though  much  attention  has  been 
given  to  the  subject.  When  observed  in  the  nests  they  frequently 
appear  as  if  asleep,  and  the  ants  do  not  take  much  notice  of 
them.  On  other  occasions  the  ants  endeavour  to  drag  them  into 
the  interior  of  the  nest,  as  if  desirous  of  retaining  their  company  : 

1  For  classification  and  structure  see  Sharp,  "On  Dytiscidae,"  Sci.   Trans.  H. 
Dublin  Soc.  (2)  ii.  1882. 


214 


COLEOPTERA 


CHAP. 


the  Paussus  then  makes  no  resistance  to  its  hosts ;  if,  however,  it 
be  touched,  even  very  slightly,  by  an  observer,  it  immediately 
bombards :  the  ants,  as  may  be  imagined,  do  not  approve  of  this, 
and  run  away.  Nothing  has  ever  been  observed  that  would  lead 
to  the  belief  that  the  ants  derive  any  benefit  from  the  presence 
of  the  Paussi,  except  that  these  guests  bear  on  some  part  of  the 
body — frequently  the  great  impressions  on  thepronotum — patches 
of  the  peculiar  kind  of  pubescence  that  exists  in  many  other  kinds 
of  ants'-nest  beetles,  and  is  known  in  some  of  them  to  secrete  a 
substance  the  ants  are  fond  of,  and  that  the  ants  have  been  seen 

to  lick  the  beetles.  On  the  other  hand,  the 
Paussi  have  been  observed  to  eat  the  eggs 
and  larvae  of  the  ants.  The  larva  of  Paussus 
is  not  known,1  and  E affray  doubts  whether 
it  lives  in  the  ants'  nests.  There  are  about 
200  species  of  Paussidae  known,  Africa,  Asia 
and  Australia  being  their  chief  countries ; 
one  species,  P.  favieri,  is  not  uncommon 
in  the  Iberian  peninsula  and  South  France, 
and  a  single  species  was  formerly  found  in 
Brazil.  The  position  the  family  should 
FIG.  98.  —  Paussus  cepha-  occupy  has  been  much  discussed ;  the  only 
(After  Raffray.)  forms  to  which  they  make  any  real  ap- 

proximation  are   Carabidae,   of   the   group 

Ozaenides,  a  group  of  ground  beetles  that  also  crepitate.  Bur- 
meister  and  others  have  therefore  placed  the  Paussidae  in  the 
series  Adephaga,  but  we  follow  Eaffray's  view  (he  being  the  most 
recent  authority  on  the  family),2  who  concludes  that  this  is 
an  anomalous  group  not  intimately  connected  with  any  other 
family  of  Coleoptera,  though  having  more  affinity  to  CarabkLie 
than  to  anything  else.  The  recently  discovered  genus  Proto- 
paussus  has  eleven  joints  to  the  antennae,  and  is  said  to  come  nearer 
to  Carabidae  than  the  previously  known  forms  did,  and  we  may  an- 
ticipate that  a  more  extensive  knowledge  will  show  that  the  family 
may  find  a  natural  place  in  the  Adephaga.  The  description  of 
the  abdomen  given  by  E  affray  is  erroneous ;  in  a  specimen  of  the 
genus  Arthropterus  the  writer  has  dissected,  lie  finds  that  there 
1  Descriptions  of  larvae  that  may  possibly  be  those  of  Paussicls  have  been  pub- 
lished by  Xambeu,  Ann.  Soe.  Linn.  Lyon,  xxxix.  1892,  p.  137,  and  Erich.son,  Arch. 
Xatiirycsch.  xiii.  1847,  p.  275. 

-  Arch.  Mus.  Paris  (2),  viii.  and  ix.  1SS7. 


POLYMORPHA — WHIRLIGIG-BEETLES 


215 


are  five  ventral  segments  visible  along  the  middle,  six  at  the 
sides,  as  in  the  families  of  Adephaga  generally.  There  is  said 
to  be  a  great  difference  in  the  nervous  systems  of  Carabidae  and 
Paussidae,  but  so  little  is  known  on  this  point  that  we  cannot 
judge  whether  it  is  really  of  importance. 

Fam.  11.  Gyrinidae  (Whirligig  beetles). --Antennae  very 
short ;  four  eyes ;  middle  and  hind  legs  forming  short  broad 
paddles  ;  abdomen  with  six  segments  visible  along  the  middle,  seven 
«/ong  each  side.  These  Insects  are  known  to  all  from  their  habit 
of  floating  lightly  on  the  surface  of  water,  and  performing  graceful 
complex  curves  round 
one  another  without 
colliding  ;  sometimes 
they  may  be  met  with 
in  great  congregations. 
They  are  admirably  con- 
structed for  this  mode 
of  life,  which  is  com- 
paratively rare  in  the 
Insect  world ;  the 
Hydrometridae  amongst 
the  bugs,  and  a  small 
number  of  different 
kinds  of  Diptera,  being 
the  only  other  Insects 
that  are  devoted  to  a 
life  on  the  surface  of  the 
waters.  Of  all  these, 
Gyrinidae  are  in  their 
construction  the  most 
adapted  for  such  a 
career.  They  are  able 
to  dive  to  escape  danger, 


FIG.  99. — A,  Larva  of  Gyrinus  (after  Schiodte)  ;  B, 
under  side  of  Gyrinus  sp.  (after  Ganglbauer).  1, 
Prosternum  ;  2,  anterior  coxal  cavity  ;  3.  raeso- 
thoracic  episternum  ;  4,  mesoepimeron  ;  5,  nieso- 
sterrmm  ;  6,  metathoracic  episternum  ;  7,  middle 
coxal  cavity  ;  8,  metasternum  ;  9,  hind  coxa  ;  10, 
ventral  segments.  [X.B. — The  first  ventral  segment 
really  consists,  at  each  side,  of  two  segments  united  ; 
this  may  be  distinctly  seen  in  many  Gyrinidae.] 


and  they  then  carry  with  them  a  small  supply  of  air,  but  do  not 
stay  long  beneath  the  surface.  Their  two  hind  pairs  of  legs  are 
beautifully  constructed  as  paddles,  expanding  mechanically  when 
moved  in  the  backward  direction,  and  collapsing  into  an  extremely 
small  space  directly  the  resistance  they  meet  with  is  in  the  other 
direction.  The  front  legs  of  these  Insects  are  articulated  to  the 
thorax  in  a  peculiar  direction  so  that  their  soles  do  not  look 


2l6  COLEOPTERA  CHAP. 

downwards  but  towards  one  another  ;  hence  the  sensitive  ad- 
hesive surface  used  during  coupling  is  placed  on  the  side  of  the 
foot,  forming  thus  a  false  sole :  a  remarkable  modification  other- 
wise unknown  in  Insects.  They  breathe  chiefly  by  means  of  the 
very  large  metathoracic  spiracles. 

The  larvae  (Fig.  99,  A)  are  purely  aquatic,  and  are  highly 
modified  for  this  life,  being  elongate  creatures,  with  sharp, 
mandibles  and  nine  abdominal  segments,  each  segment  bearing 
on  each  side  a  tracheal  branchia ;  these  gills  assist  to  some  extent 
in  locomotion.  The  stigmata  are  quite  obsolete,  but  the  terminal 
segment  bears  four  processes,  one  pair  of  which  may  be  looked  on 
as  cerci,  the  other  as  a  pair  of  gills  corresponding  with  the  pair 
on  each  of  the  preceding  segments.  The  mandibles  are  not 
suctorial,  but,  according  to  Meinert,  possess  an  orifice  for  the 
discharge  of  the  secretion  of  a  mandibular  gland.  Gyrinidae 
are  chiefly  carnivorous  in  both  the  larval  and  imaginal  instars. 
Fully  300  species  are  known;  they  are  generally  distributed, 
though  wanting  in  most  of  the  islands  of  the  world  except  those 
of  large  size.  The  finest  forms  are  the  Brazilian  Enliydrus  and 
the  Porrorhynchus  of  tropical  Asia.1  In  Britain  we  have  nine 
species,  eight  of  Gyrinus,  one  of  Orectochilus ;  the  latter  form  is 
rarely  seen,  as  it  hides  during  the  day,  and  performs  its  rapid 
gyrations  at  night. 

The  Gyrinidae  are  one  of  the  most  distinct  of  all  the  families 
of  Coleoptera  :  by  some  they  are  associated  in  the  Aclephagous 
series ;  but  they  have  little  or  no  affinity  with  the  other  mem- 
bers thereof.  Without  them  the  Adephaga  form  a  natural  series 
of  evidently  allied  families,  and  we  consider  it  a  mistake  to  force 
the  Gyrinidae  therein  because  an  objection  is  felt  by  many  tax- 
ouomists  to  the  maintenance  of  isolated  families.  Surely  if 
there  are  in  nature  some'  families  allied  and  others  isolated,  it  is 
better  for  us  to  recognise  the  fact,  though  it  makes  our  classifi- 
cations look  less  neat  and  precise,  and  increases  the  difficulty  of 
constructing  "  tables." 

Fam.  12.  Hydrophilidae.--T#m  five-jointed,  the  first  joint 
in  many  cases  so  small  as  to  be  scarcely  evident:  antennae 
short,  of  less  than  eleven  joints,  not  filiform,  but  consisting  of 

1  For  classification  and  monograph  of  the  family,  see  Regimbart,  Ann.  Svc.  ent. 
France,  1882,  1883,  and  1886.  For  a  catalogue,  Severin,  Ann.  Soe.  cnt.  Hclyiqi" , 
xxxiii.  1889. 


v  POLYMORPHA HYDROPHILIDAE  2  I / 

three  parts,  a  basal  part  of  one  or  two  elongate  joints,  an  inter- 
mediate part  of  two  or  more  small  joints,  and  an  apical  part  of 
lui-ger  (or  at  any  rate  broader}  joints,  which  are  pubescent,  the  others 
being  bare.  Outer  lobe  of  maxillae  usually  complex,  but  not  at 
all  palpiform,  maxillary  palpi  of  ten  very  long ;  the  parts  of  the 
labium  much  concealed  behind  the  mentum,  the  labial  palpi  very 
widely  separated.  Hind  coxae  extending  the  width  of  the 
body,  short,  the  lamina  interior  small  in  comparison  with  the 
lamina  exterior.  Abdomen  of  Jive  visible  segments.  The  Hydro- 
philidae  are  an  extensive  family  of  beetles,  unattractive  in  colours 
and  appearance,  and  much  neglected  by  collectors.  A  large  part 
of  the  family  live  in  water,  though  most  of  them  have  only 
feeble  powers  of  aquatic  locomotion,  and  the  beetles  appear 
chiefly  to  devote  their  attention  to  economising  the  stock  of  air 
each  individual  carries  about.  The  best  known  forms  of  the 
family  are  the  species  of  Hydrophilus.  They  are,  however,  very 
exceptional  in  many  respects,  and  are  far  more  active  and  pre- 
daceous  than  most  of  the  other  forms.  Much  has  been  written 
about  Hydrophilus  piceus,  one  of  the  largest  of  British  beetles. 
This  Insect  breathes  in  a  most  peculiar  manner :  the  spiracles 
are  placed  near  bands  of  delicate  pubescence,  forming  tracts  that 
extend  the  whole  length  of  the  body,  and  in  this  particular 
species  cover  most  of  the  under  surface  of  the  body ;  these 
velvety  tracts  retain  a  coating  of  air  even  when  the  Insect  is 
submerged  and  moves  quickly  through  the  water.  It  would 
appear  rather  difficult  to  invent  a  mechanism  to  supply  these 
tracts  with  fresh  air  without  the  Insect  leaving  the  water ;  but 
nevertheless  such  a  mechanism  is  provided  by  the  antennae  of 
the  beetle,  the  terminal  joints  of  which  form  a  pubescent  scoop, 
made  by  some  longer  hairs  into  a  funnel  sufficiently  large  to 
convey  a  bubble  of  air.  The  Insect  therefore  rises  to  the  sur- 
face, and  by  means  of  the  antennae,  which  it  exposes  to  the  air, 
obtains  a  supply  with  which  it  surrounds  a  large  part  of  its 
body ;  for,  according  to  Miall,  it  carries  a  supply  on  its  back, 
under  the  elytra,  as  well  as  on  its  ventral  surface.  From  the 
writer's  own  observations,  made  many  years  ago,  he  inclines  to 
the  opinion  that  the  way  in  which  the  Hydrophilus  uses  the 
antennae  to  obtain  air  varies  somewhat  according  to  circumstances. 
Many  of  the  members  of  the  sub-family  Hydrophilides  con- 
struct egg-cocoons.  In  the  case  of  Hydrophilus  piceus,  the  boat- 


218 


COLEOPTERA 


CHAP. 


like  structure  is  provided  with  a  little  mast,  which  is  supposed  by 
some  to  be  for  the  purpose  of  securing  air  for  the  eggs.  Helo- 
cliares  and  Spercheus  (Fig.  100)  carry  the  cocoon  of  eggs  attached 

to  their  own  bodies.  Philydrus  constructs, 
one  after  the  other,  a  number  of  these 
egg-bags,  each  containing  about  fifteen 
eggs,  and  fixes  each  bag  to  the  leaf  of 
some  aquatic  plant ;  the  larvae  as  a  rule 
hatch  speedily,  so  that  the  advantage  of 
the  bag  is  somewhat  problematic. 

The  larvae  of  the  aquatic  division  of 
the  family  have  been  to  a  certain  extent 
studied  by  Schiodte  and  others  ;  those  of 
the  Sphaeridiides — the  terrestrial  group 
of  the  family — are  but  little  known.  All 
the  larvae,  seem  to  be  predaceous  and 
carnivorous,  even  when  the  imago  is  of 
vegetable -feeding  habits  ;  and  Dumi'ril 
FIG.  100.  —  Spercheus  emar-  states  that  in  Hydrous  caroboides  the 

gmatus    ?.      Britain.      A, 

Upper  surface  of  beetle ;  alimentary     canal     undergoes     a     great 
B,  under  surface  of  abdo-  c]lange  at  tjie   period   of  metamorphosis, 

nifiii.     with     the     egg -sac 


B 


men. 


ruptured  and  some  of  the  becoming    very    elongate    in    the    adult, 
JS  escaping.  though  in   the   larva  "it  was  short,      The 

legs  are  never  so  well  developed  as  they  are  in  the  Adephaga, 
the  tarsi  being  merely  claw -like  or  altogether  wanting;  the 
mandibles  are  never  suctorial.  The  respiratory  arrangements 
show  much  diversity.  In  most  of  the  Hydrophilides  the  process 
is  carried  on  by  a  pair  of  terminal  spiracles  on  the  eighth 
abdominal  segment,  as  in  Dytiscidae,  and  these  are  either 
exposed  or  placed  in  a  respiratory  chamber.  In  Bcrosus  the 
terminal  stigmata  are  obsolete,  and  the  sides  of  the  body  bear 
long  branchial  filaments.  Cussac  says  that  in  fycrcliev.s  (Fig. 
101)  there  are  seven  pairs  of  abdominal  spiracles,  and  that  the 
larva  breathes  by  presenting  these  to  the  air ; l  but  Schiodte 
states  that  in  this  form  there  are  neither  thoracic  nor  abdominal 
spiracles,  except  a  pair  placed  in  a  respiratory  chamber  on  the 
eighth  segment  of  the  abdomen,  after  the  manner  described  by 
Miall  as  existing  in  Hydrol'm*.  No  doubt  Cussac  was  wrong  in 
supposing  the  peculiar  lateral  abdominal  processes  to  be  stig- 

1  Ann.  Soc.  cut.  France,  xxi.  1852,  p.  619. 


POLYMORPHA HYDROPHILIDAE PLATYPSYLLIDAE     2  I  9 


matiferous.  In  Berosus  there  are  patches  of  aeriferous,  minute 
pubescence  on  the  body.  The  pupae  of  Hydrophilides  repose  on 
the  dorsal  surface,  which  is  protected  by 
spinous  processes  on  the  pronotum,  and 
on  the  sides  of  the  abdomen. 

We  have  already  remarked  that  this 
is  one  of  the  most  neglected  of  the 
families  of  Coleoptera,  and  its  classifica- 
tion is  not  satisfactory.  It  is  usually 
divided  into  Hydrophilides  and  Sphaer- 
idiides.  The  Sphaeridiid.es  are  in  large 
part  terrestrial,  but  their  separation  from 
the  purely  aquatic  Hydrophilides  cannot 
be  maintained  on  any  grounds  yet  pointed 
out.  Altogether  about  1000  species  of 
Hydrophilidae  are  known,  but  this  pro- 
bably is  not  a  tenth  part  of  those  exist-  FIG.  101.— -Larva  of  Spercheus 
T  T>  -j.  •  i  i  •  emarginatus.  (After 

ing.      In  Britain  we  have   nearly  ninety        Schiodte). 

species.       Some    taxononiists    treat    the 

family  as  a  series  with  the  name  Palpicornia.  The  series  Phil- 
hydrida  of  older  authors  included  these  Insects  and  the  Parnidae 
and  Heteroceridae. 

Fam.  13.  Platypsyllidae.--This  consists  of  a  single  species. 
It  will  be  readily  recognised  from  Fig.  102,  attention  being  given 
to  the  peculiar  antennae,  and  to  the  fact  that  the  mentum  is  tri- 
lobed  behind.  This  curious  species  has  been  found  only  on  the 
beaver.  It  was  first  found  by  Ritsema  on  American  beavers 
(Castor  canadensis)  in  the  Zoological  Gardens  at  Amsterdam,  but 
it  has  since  been  found  on  wild  beavers  in  the  Rhone  in  France  ; 
in  America  it  appears  to  be  commonly  distributed  on  these 
animals  from  Alaska  to  Texas.  It  is  very  remarkable  that  a 

t/ 

wingless  parasite  of  this  kind  should  be  found  in  both  hemi- 
spheres. The  Insect  was  considered  by  Westwood  to  be  a  separate 
Order  called  Achreioptera,  but  there  can  be  no  doubt  that  it  is  a 
beetle.  It  is  also  admitted  that  it  shows  some  points  of  resem- 
blance with  Mallophaga,  the  habits  of  which  are  similar.  Its 
Coleopterous  nature  is  confirmed  by  the  larva,  which  has  been 
described  by  both  Horn  and  Eiley.1  Little  is  known  as  to  the 
food  and  life-history.  Horn  states  that  the  eggs  are  placed  on 

1  Horn,  Tr.  Amer.  cut.  Soc.  xv.  1888,  p.  23  ;  Riley,  Insect  Life,  i.  1S89,  p.  300. 


22O 


COLEOPTERA 


CHAP. 


the  skin  of  the  beaver  amongst  the  densest  hair  ;  the  larvae  move 
with  a  sinuous  motion,  like  those  of  Staphylinidae.      It  has  been 


B 


FIG.  102. — Platypsyllus  castoris.     A,  Upper  side  ;  B,  lower  side,  with  legs  of  one  side 
removed  ;  C,  antenna.     (After  Westwood.) 

suggested    that    the    Insect    feeds    on    an    Acarid,   Schizocarpus 
mintjandi ;  others  have  supposed  that  it  eats  scales  of  epithelium 

or  hairs  of  the  beaver. 

Fam.  14.  Leptinidae.  -  -  Antennae 
rather  long,  eleven-jointed,  without  club,  bet 
a  little  thicker  at  the  extremity.  Eyes  absent 
or  imperfect.  Tarsi  five- jointed.  Elytra 
quite,  covering  abdomen.  Mentum  with  the 
posterior  angles  spinoiisly  prolonged.  A 
family  of  only  two  genera  and  two  species. 
Their  natural  history  is  obscure,  but  is 
apparently  of  an  anomalous  nature ;  the 
inference  that  may  be  drawn  from  the 
little  that  is  known  being  that  they  are 
parasitic  on  mammals.  There  is  little  or 
nothing  in  their  structure  to  indicate  this, 

except    the    condition    of  blindness ;   and 
FIG.  103. — Lent  inns  testaceus.  T  i        -,c     i 

Britain  until  recently  the  Insects  were  classified 

amongst     Silphidae.       Leptinus     testaceus 

(Fig.  103)  is  a  British  Insect,  and  besides  occurring  in  Europe 
is  well  known  in  North  America.      In  Europe  it  has  been   found 


v  POLYMORPHA LEPTINIDAE SILPHIDAE  221 

in  curious  places,  including  the  nests  of  mice  and  bumble-bees. 
In  America  it  has  been  found  on  the  mice  themselves  by  Dr. 
Ryder,  and  by  Riley  in  the  nests  of  a  common  field-mouse, 
together  with  its  larva,  which,  however,  has  not  been  described. 
The  allied  genus  Leptinillus  is  said  by  Riley  to  live  on  the 
beaver,  in  company  with  Platypsyllus?  It  has  been  suggested 
that  the  natural  home  of  the  Leptinus  is  the  bee's  nest,  and 
that  perhaps  the  beetle  merely  makes  use  of  the  mouse  as  a 
means  of  getting  from  one  nest  of  a  bumble-bee  to  another. 

Fam.  15.  Silphidae. — The  mentum  is  usually  a  transverse 
plate,  having  in  front  a  membranous  hypoglottis,  which  bears  the 
exposed  labial  palpi,  and  immediately  behind  them  the  so-called 
bilobed  ligula.  The  anterior  coxae  are  conical  and  contiguous : 
prothoracic  epimera  and  episterna  not  distinct.  Visible  abdomi- 
nal segments  usually  Jive,  but  sometimes  only  four,  or  as  many  as 
seven.  Tarsi  frequently  Jive-jointed,  but  often  with  one  joint  less. 
Elytra  usually  covering  the  body  and  free  at  the  tips,  but  occasion- 
ally shorter  than  the  body,  and  even  truncate  behind  so  as  to  expose 
from  one  to  four  of  the  dorsal  plates;  but  there  are  at  least  three 
dorsal  plates  in  a  membranous  condition  at  the  base  of  the  abdomen. 
These  beetles  are  extremely  diverse  in  size  and  form,  some  being 
very  minute,  others  upwards  of  an  inch  long,  and  there  is  also 
considerable  range  of  structure.  In,  this  family  are  included 
the  burying-beetles  (Necrophorus),  so  well  known  from  their  habit 
of  making  excavations  under  the  corpses  of  small  Vertebrates, 
so  as  to  bury  them.  Besides  these  and  Silpha,  the  roving 
carrion  -  beetles,  the  family  includes  many  other  very  different 
forms,  amongst  them  being  the  larger  part  of  the  cave-beetles 
of  Europe  and  North  America.  These  belong  mostly  to  the 
genera  Bathyscia  in  Europe,  and  Adelops  in  North  America  ;  but 
of  late  years  quite  a  crowd  of  these  eyeless  cave-beetles  of  the 
group  Leptoderini  have  been  discovered,  so  that  the  European 
catalogue  now  includes  about  20  genera  and  150  species.  The 
species  of  the  genus  Catopomorphus  are  found  in  the  nests  of 
ants  of  the  genus  Aphaenogaster  in  the  Mediterranean  region. 
Scarcely  anything  is  known  as  to  the  lives  of  either  the  cave- 
Silphidae  or  the  myrmecophilous  forms. 

The  larvae  of  several  of  the  larger  forms  of  Silphidae  are  well 
known,  but  very  little  has  been  ascertained  as  to  the  smaller  forms. 

1  Insect  Life,  i.  1889,  pp.  200  and  306. 


222 


COLEOPTERA 


CHAP. 


Those  of  the  burying-beetles  have  spiny  plates  on  the  back  of  the 
body,  and  do  not  resemble  the  other  known  forms  of  the  family. 
The  rule  is  that  the  three  thoracic  segments  are  well  developed, 
and  that  ten  abdominal  segments  are  also  distinct  ;  the  ninth 
abdominal  segment  bears  a  pair  of  cerci,  which  are  sometimes 
elongate.  Often  the  dorsal  plates  are  harder  and  better  developed 
than  is  usual  in  Coleopterous  larvae.  This  is  especially  the  case 

with  some  that  are  en- 
dowed with  great  powers 
of  locomotion,  such  as  8. 
obscura  (Fig.  104).  The 
food  of  the  larvae  is  as  a 
rule  decomposing  animal 
or  vegetable  matter,  but 
some  are  predaceous,  and 
attack  living  objects. 
The  larger  Silplia  larvae 
live,  like  the  Necro- 
plmrus,  on  decomposing 
animal  matter,  but  run 

obscuni.     Europe,    ''bout  to    Seek    it;    hence 

lacrymosa,    many  Specimens   of  SOme 
J 

ot  these  large  larvae  may 
sometimes  be  found  amongst  the  bones  of  a  very  small  dead  bird. 
We  have  found  the  larva  and  imago  of  8.  tJwracica  in  birds'  nests 
containing  dead  nestlings.  8.  atrata  and  8.  laevigata  make  war 
on  snails.  S.  lapponica  enters  the  houses  in  Lapland  and  ravages 
the  stores  of  animal  provisions.  8.  opaca  departs  in  a  very 
decided  manner  from  the  habits  of  its  congeners,  as  it  attacks 
beetroot  and  other  similar  crops  in  the  growing  state  ;  it  is 
sometimes  the  cause  of  serious  loss  to  the  growers  of  beet.  The 
larvae  of  the  group  Anisotomides  are  believed  to  be  chiefly 
subterranean  in  habits  ;  that  of  A.  cinnamomea  feeds  on  the 
truffle,  and  the  beetle  is  known  as  the  truffle-beetle. 

The  number  of  species  of  Silphidae  known  must  be  at  present 
nearer  900  than  800.  Of  these  an  unusually  large  proportion  lie- 
long  to  the  European  and  North  American  regions  ;  Silphidae  being 
apparently  far  from  numerous  in  the  tropics.  Rather  more  than 
100  species  are  natives  of  Britain.  The  family  reappears  incon- 
siderable force  in  New  Zealand,  and  is  probably  well  represented 


FIG.    104.—  A,    Larva    of 
(After    Schiodte).       B, 
Australia. 


v  SCYDMAENIDAE — GNOSTIDAE PSELAPHIDAE  223 

in  South  Australia  and  Tasmania.  The  most  remarkable  form 
known  is  perhaps  the  Australian  genus  Ptomaphila  (Fig.  104,  B). 
The  classification  of  the  family  is  due  to  J)r.  Horn.1  The 
only  change  of  importance  that  has  since  been  suggested  is 
the  removal  of  Sphaerites  from  this  family  to  Synteliidae. 
Anisotomidae  and  Clambidae  have  been  considered  distinct 
families,  but  are  now  included  in  Silphidae. 

Fam.  16.  Scydmaenidae. — Minute  Insects  allied  to  Silphidae, 
I  nit  with  the  hind  coxae  separated,  and  the  facets  of  the  eyes  coarser  ; 
the  tarsi  are  five-jointed  ;  the  number  of  visible  abdominal  segments  is 
six.  These  small  beetles  are  widely  spread  over  the  earth's  surface, 
and  about  700  species  are  now  known,  of  which  we  have  about  a 
score  in  Britain  ;  many  live  in  ants'  nests,  but  probably  usually 
rather  as  intruders  than  as  guests  that  have  friendly  relations 
with  their  hosts.  Nothing  is  known  as  to  their  life-histories,  but 
the  food  of  the  imago,  so  far  as  is  known,  consists  of  Acari.  Mastigus 
is  a  very  aberrant  form,  found  in  moss  and  dead  leaves  in  Southern 
Europe.  By  means  of  Brathinus  the  family  is  brought  very  near 
to  Silphidae  ;  Casey,  however,  considers  Brathinus  to  belong  to 
Staphylinidae  rather  than  to  Scydmaenidae.  The  South  European 
Leptomastax  is  remarkable  on  account  of  the  slender,  long,  sickle- 
shaped  mandibles.  The  Oriental  genus  Clidicus  is  the  largest  and 
most  remarkable  form  of  the  family ;  it  has  a  very  slender  neck 
to  its  broad  head,  and  is  more  than  a  quarter  of  an  inch  long. 

Fam.  17.  Gnostidae.  -  -  Minute  Insects  with  three-jointed 
antennae,, five-jointed  tarsi,  and  three  apparent  ventral  segments,  the 
first  of  which,  however,  is  elongate,  and  consists  of  three  united 
plates.  Elytra  entirely  covering  the  after-body.  The  family  con- 
sists of  two  species  which  have  been  found  in  the  nests  of  ants, 
of  the  genus  Cremastogaster,  in  Brazil.2 

Fam.  18.  Pselaphidae.  Very  small  Insects ;  the  elytra  much 
abbreviated,  usually  leaving  as  much  as  half  the  abdomen  uncovered  ; 
the  maxillary  palpi  usually  greatly  developed,  and  of  a  variety  of 
remarkable  forms;  the  segments  of  the  abdomen  not  more  than 
seven  in  number,  with  little  or  no  power  of  movement.  T<t  rxi  •//•//// 
not  more  than  three  joints.  These  small  Coleoptera  mostly  live  in 
the  nests  of  ants,  and  present  a  great  diversity  of  extraordinary 

1   Tr.  Amer.  ent.  Soc.  viii.  1880,  pp.  219-321. 

!  Westwood,    Tr.   cni.    Soc.   London  (X.S.)  iii.   1855,    p.   90;  Wasmaim,   Krit. 
Verzeichniss  Myrmekoph.  Arthropod.  1894,  p.  121. 


224  COLEOPTERA  CHAP. 

shapes,  and  very  peculiar  structures  of  the  antennae  and  maxillary 
palpi.  Owing  to  the  consolidation  of  some  of  its  segments,  the 
abdomen  frequently  appears  to  have  less  than  the  usual  number. 
In  the  curious  sub-family  Clavigerides,  the  antennae  may  have 
the  joints  reduced  to  two  or  even,  to  all  appearance,  to  one ;  the 
tarsi  suffer  a  similar  reduction.  There  are  about  2500  species  of 
Pselaphidae  known  ;  many  of  them  have  never  been  found  outside 
the  ants'  nests ;  very  little,  however,  is  known  as  to  their  natural 
history.  It  is  certain  that  some  of  them  excrete,  from  little 
tufts  of  peculiar  pubescence,  a  substance  that  the  ants  are  fond 
of.  The  secretory  patches  are  found  011  very  different  parts  of 
the  body  and  appendages.  Claviger  testaceus  is  fed  by  the  ants 
in  the  same  way  as  these  social  Insects  feed  one  another  ;  the 
Claviger  has  also  been  seen  to  eat  the  larvae  of  the  ants.  They 
ride  about  on  the  backs  of  the  ants  when  so  inclined.  The 
family  is  allied  to  Staphylinidae,  but  is  easily  distinguished  by 
the  rigid  abdomen.  Only  one  larva — that  of  Chennium  bituber- 
c'ulatum — is  known.  It  appears  to  be  very  similar  to  the  larvae 
of  Staphylinidae.  The  best  account  of  classification  and  structure 
is  that  given  by  M.  Achille  Eaffray,1  who  has  himself  discovered 
and  described  a  large  part  of  the  known  species. 

Fam.  19.  Staphylinidae. — Elytra  very  short,  leaving  always 
some  of  the  abdominal  segments  exposed,  and  covering  usually  only 
two  of  the  segments.  Abdomen  usually  elongate,  with  ten  dorsal,  an  ft 
seven  or  eight  ventral  segments ;  of  the  latter  six  or  seven  are  usual/// 
exposed;  the  dorsal  plates  as  hard  as  the  ventral,  except  sometime 
in  the  case  of  the  first  two  segments ;  the  segments  very  mobile,  so 
lit  at  the  abdomen  can  be  curled  upwards.  The  number  of  tar  sal 
joints  very  variable,  often  Jive,  but  frequently  as  few  as  three,  and 
not  ahoays  the  same  on  all  the  feet.  Staphylinidae  (formerly  called 
Brachelytra  or  Microptera)  is  one  of  the  most  extensive  of  even 
the  great  families  of  Coleoptera ;  notwithstanding  their  diversity, 
they  may  in  nearly  all  cases  be  recognised  by  the  more  than 
usually  mobile  and  uncovered  abdomen,  combined  with  the  fact 
that  the  parts  of  the  mouth  are  of  the  kind  we  have  mentioned 
in  Silphidae.  The  present  state  of  the  classification  of  this 
family  has  been  recently  discussed  by  Ganglbauer.2  At  present 

1  Rev.  cnt.  franc,  ix.  1890. 

Die  Kdfer  von  Mitteleuropa :  II.  Familicnreihc,  Staphylinoideu.     Vienna,  1895 
and  1899. 


POLYMORPHA STAPHYLIXIDAE 


225 


a  limit  9000  species  are  known,  some  of  which  are  minute,  while 
scarcely  any  attain  a  size  of  more  than  an  inch  in  length,  our 
cm  union  British  black  cock-tail,  or  "devil's  coach-horse  beetle," 
(_)i'!/l>nx  oh  us,  being  amongst  the  largest.  Though  the  elytra 
are  short,  the  wings  in  many  forms  are  as  large  as  those  of 
the  majority  of  beetles;  indeed  many  Staphylinidae  are  more 
apt  at  taking  flight  than  is  usual  with  Coleoptera ;  the  wings 
when  not  in  use  are  packed  away  under  the  short  elytra, 
being  transversely  folded,  and  otherwise  crumpled,  in  a  com- 
plicated but  orderly  manner.  It  is  thought  that  the  power 
of  curling  up  the  abdomen  is 
connected  with  the  packing 
away  of  the  wings  after  flight ; 
but  this  is  not  the  case :  for 
though  the  Insect  sometimes 
experiences  a  difficulty  in  fold- 
ing the  wings  under  the  elytra 
after  they  have  been  expanded, 
yet  it  overcomes  this  difficulty 
by  slight  movements  of  the  base 
of  the  abdomen,  rather  than 
by  touching  the  wings  with 
the  tip.  What  the  value  of 
this  exceptional  condition  of 
short  elytra  and  corneous  dorsal 
abdominal  segments  to  the  , 

FIG.  105.— Staphylinidae.    A,  Larva  of  Pln- 
Insect     may    be    IS     at     present          lonthusnitidus.  Britain.  (After  Schiddte.) 

« I  uite  mysterious.     The   habits       B-  °^Mf  o!?ns>  Brit/lil1  >  ,C'  ^  °f  aljd°- 

1  .  men,  of  0.  olens   \vith  stink-vessels. 

of  the  members  of  the  family 

are  very  varied ;  many  run  with  great  activity ;  the  food  is 
very  often  small  Insects,  living  or  dead ;  a  great  many  are 
found  in  fungi  of  various  kinds,  and  perhaps  eat  them.  It  is 
in  this  family  that  we  meet  with  some  of  the  most  remarkable 
cases  of  symbiosis,  i.e.  lives  of  two  kinds  of  creatures  mutually 
accommodated  with  good  will.  The  relations  between  the 
Staphylinidae  of  the  genera  Atemeles  and  Lomechusa,  and  certain 
ants,  in  the  habitations  of  which  they  dwell,  are  very  interesting. 
The  beetles  are  never  found  out  of  the  ants'  nests,  or  at  any  rate 
not  very  far  from  them.  The  most  friendly  relations  exist  between 
them  and  the  ants :  they  have  patches  of  yellow  hairs,  and  these 
VOL.  vr  Q 


226  COLEOPTERA 


CHAP. 


apparently  secrete  some  substance  with  a  flavour  agreeable  to  the 
ants,  which  lick  the  beetles  from  time  to  time.  On  the  other 
hand,  the  ants  feed  the  beetles  ;  this  they  do  by  regurgitating 
food,  at  the  request  of  the  beetle,  on  to  their  lower  lip,  from  which 
it  is  then  taken  by  the  beetle  (Fig.  82).  The  beetles  in  many 
of  their  movements  exactly  resemble  the  ants,  and  their  mode 
of  requesting  food,  by  stroking  the  ants  in  certain  ways,  is  quite 
ant-like.  So  reciprocal  is  the  friendship  that  if  an  ant  is  in 
want  of  food,  the  Lomecliusa  will  in  its  turn  disgorge  for  the 
benefit  of  its  host.  The  young  of  the  beetles  are  reared  in  the 
nests  by  the  ants,  who  attend  to  them  as  carefully  as  they  do  to 
their  own  young.  The  beetles  have  a  great  fondness  for  the 
ants,  and  prefer  to  sit  amongst  a  crowd  thereof;  they  are 
fond  of  the  ants'  larvae  as  food,  and  indeed  eat  them  to  a 
very  large  extent,  even  when  their  own  young  are  receiving 
food  from  the  ants.  The  larva  of  Lonn'di  usa,  as  described  by 
Wasmann  (to  whom  we  are  indebted  for  most  of  our  knowledge 
of  this  subject),1  when  not  fully  grown,  is  very  similar  to  the 
larvae  of  the  ants ;  although  it  possesses  legs  it  scarcely  uses 
them :  its  development  takes  place  with  extraordinary  rapidity, 
two  days,  at  most,  being  occupied  in  the  egg,  and  the  larva 
completing  its  growth  in  fourteen  days.  Wasmann  seems  to  be 
of  opinion  that  the  ants  scarcely  distinguish  between  the  beetle- 
larvae  and  their  own  young  ;  one  unfortunate  result  for  the  beetle 
follows  from  this,  viz.  that  in  the  pupal  state  the  treatment  that 
is  suitable  for  the  ant -larvae  does  not  agree  with  the  beetle- 
larvae  :  the  ants  are  in  the  habit  of  digging  up  their  own  kind 
and  lifting  them  out  and  cleaning  them  during  their  meta- 
morphosis ;  they  also  clo  this  with  the  beetle-larvae,  with  fatal 
results ;  so  that  only  those  that  have  the  good  fortune  to  be 
forgotten  by  the  ants  complete  their  development.  Thus  from 
thirty  Lomechusa  larvae  Wasmann  obtained  a  single  imago,  and 
from  fifty  Ate  //teles  larvae  not  even  one. 

Many  other  Staphylinidae  are  exclusively  attached  to  ants' 
nests,  but  most  of  them  are  either  robbers,  at  warfare  with  the 
ants — as  is  the  case  with  many  species  of  Myrmedonia  that  lurk 
about  the  outskirts  of  the  nests — or  are  merely  tolerated  by  the 
ants,  not  receiving  any  direct  support  from  them.  The  most 

1   J'crylcichende  Studien   «/»r  Amfiscngiistc,  Xijhoff,    1890;   and   Tijdschr.  cut. 
xxxiii.  1890,  pp.  93,  etc.  ;  T,wl.  Ccntralbl.  xv.  1895,  p.  632. 


v     STAPHYLTNIDAE SPHAERIIDAE TRICHOPTL-.RYGIDAE    22/ 


the 

The 


remarkable  Staphylinidae  yet  discovered  are  some  viviparous 
species,  forming  the  genera  Corotoca  and  Spiraclitlia,  that  h;i\i- 
very  swollen  abdomens,  and  live  in  the  nests  of  Termites  in 
Brazil:1  very  little  is,  however,  known  about  them.  A  very 
l;irge  and  powerful  Staphylinid,  Velleius  dilatatus,  lives  only  in 
the  nests  of  hornets  and  wasps.  It  has  been  supposed  to  be  a 
defender  of  the  Hymenoptera,  but  the  recent  observations  of 
Janet  and  Wasmann  make  it  clear  that  this  is  not  the  case  :  the 
Velleius  has  the  power  of  making  itself  disagreeable  to 
hornets  by  some  odour,  and  they  do  not  seriously  attack  it. 
Velleius  finds  its  nutriment  in  larvae  or 
pupae  of  the  wasps  that  have  fallen  from 
their  cells,  or  in  other  organic  refuse. 

The  larvae  of  Staphylinidae  are  very 
similar  to  those  of  Carabidae,  but  their 
legs  are  less  perfect,  and  are  terminated 
only  by  a  single  claw ;  there  is  no  dis- 
tinct labruni.  The  pupae  of  some  are 
obtected,  i.e.  covered  by  a  secondary  exu- 
dation that  glues  all  the  appendages 
together,  and  forms  a.  hard  coat,  as  in 
Lepidoptera.  We  have  about  800  species 
of  Staphylinidae  in  Britain,  and  it  is  prob- 
able that  the  family  will  prove  one  of  the 
most  extensive  of  the  Order.  It  is  prob- 
able that  one  hundred  thousand  species 
or  even  more  are  at  present  in  existence. 

Fam.  20.  Sphaeriidae.  -  -  Very 
minute.  Antennae  eleven-jointed,  clubbed. 
Tarsi  three-jointed.  Abdomen  icith  only 
three  visible  ventral  segments.  This  family 
includes  only  three  or  four  species  of  In- 
sects about 

very  convex,  and  may  be  found  walking 
on  mud.  8.  acaroides  occurs  in  our  fens. 
Mr.  Matthews  considers  that  they  are 
most  nearly  allied  to  Hydrophilidae.2 

Fam.   21.   Trichopterygidae. — Extremal;/    minute:    aiit<:/in<i<- 


of  an  inch  long.    They  are  FlG-    106.— TYicAopferys  /«*»- 

cularis.  Britain.  A,  Gut- 
line  of  perfect  Insect  ;  B, 
part  of  upper  surface  ;  C, 
larva  from  side  ;  D,  from 
above  ;  E,  pupa  ;  F,  wiug  ; 
G,  natural  size  of  imago. 


1  Schiodte,  Ann.  Sci.  Nat.  Zool.  (4)  v.  1857,  p.  169. 
-  Mol.  Centr.  Amer.  Col.  ii.  pt.  i.  1888,  p.  156. 


228 


COLEOPTERA 


CHAP. 


clavicorn  (bfisid  and  <q>ic«l  joints  thicker  than  middle  joints} ;  tarsi 
three-jointed;  elytra  so'inctinirs  covering  abdomen,  in  other  cases 
leaving  a  variable  number  of  segments  exposed;  'icings  fringed. 
Tliis  family  comprises  the  smallest  Insects  ;  Nanosella  fungi  being 
only  y-J-Q-  of  an  inch  long,  while  the  largest  Trj.choptej.ygid  is 
only  yV  of  an  inch.  The  small  size  is  not  accompanied  by  any 
degeneration  of  structure,  the  minute,  almost  invisible  forms,  having 
as  much  anatomical  complexity  as  the  largest  Insects.  Very  little 
is  known  as  to  the  natural  history.  Probably  these  Insects  exist  in 
all  parts  of  the  world,  for  we  have  about  eighty  species  in  England, 
and  Trichopterygidae  are  apparently  numerous  in  the  tropics.1 

Fam.  22.  Hydroscaphidae. —  Extremely  minute  aquatic  Insects, 
•t'-i/h  chingnte  abdomen.  Antennae  eight -jointed.  The  other 
characters  are  much  the  same  as  those  we  have  mentioned  for 
Trichopterygidae.  The  family  is  not  likely  to  come  before  the 
student,  as  only  three  or  four  species  from  Southern  Europe  and 
North  America  are  known." 

Fam.  23.  Corylophidae. — Minute  beetles.  Tarsi  fonr-jn', ni> <1 . 
Imt  tijtj>i'ii,-i  ,i<i  on///  three -jointed,  oii'i/nj  to  the  hind  joint  bring 
nnirrti/rd  ////  tlie  <  inn i'i/i n<itc  (or  notched^)  second  j<>i/if.  tiix  free 
ventral  segments.  Maxillae  v.'ith  only  one  lobe.  Antfiiiuir  of 

peculiar  form.  There  are  about 
200  species  of  these  little  Insects, 
but  the  family  is  apparently  repre- 
sented all  over  the  world,  and  will 
probably  prove  to  be  much  more 
extensive.  The  peculiar  larva  of 
Ortlioperus  brunnipes  was  found 
abundantly  by  Perris  in  thatch  in 
France.  Mr.  Matthews  proposes 
to  separate  the  genus  Aphanoceph- 
alus  as  a  distinct  family,  Pseudocory- 
FIG.  107.— A,  Larva  of  Orthoperus  lophidae.3  In  Corylophidae  the 

brim  ill  ties  (after  Perris);  B,  0.  <'/"-         •  r.  •  • ,-, 

marius,  perfect  Insect.     Britain.      wmgs    are    fringed    With    long     hairs, 

as    is   the    case    in    so    many    small 

Insects:  the  species  of  Aphanoceplialus  are  rather  larger  Insects, 
and  the  wings  are  not  fringed  ;  the  tarsi  are  only  three-jointed. 

Monograph,  Trichopterygia  illustrata,  by  A.  Matthews,  London,  1872. 
2  For  further  information  refer  to  Matthews,  An  Essay  on  Hydroscapha,  London, 


B 


\ 


1S76,  20  pp.  1  pi. 


Hist.  (5)  xix.  1887,  p.  115. 


POLYMORPRA SCAPHIDIIDAE — SYNTELIIDAE 


229 


Fam.  24.  Scaphidiidae. — Front  coxae  small,  conical;  prothorax 

very  closely  applied  to  the  after-body  ;  bind  coxae  transverse,  witlcl;/ 
separated :  abdomen  with  six  or  seven  visible  ventral  plates ; 
antennae  at  the  extremity  with  about  Jive  joints  that  become 
<l  fa  dually  broader.  Tarsi  Jive-jointed.  This  family  consists  of  a 
few  beetles  mat  live  in  fungi,  and  run  with  extreme  rapidity  ; 
they  are  all  small,  and  usually  rare  in  collections.  Some  of  the 
exotic  forms  are  remarkable  for  the  ex- 
treme tenuity  and  fragility  of  the  long 
antennae,  which  bear  fine  hairs.  The 
number  of  described  species  does  not  at 
present  reach  200,  but  the  family  is  very 
widely  distributed.  We  have  three  or 
four  species  in  Britain.  All  we  know  of 
the  larvae  is  a  description  of  'that  of 
Scaphisoma  agaricinum  by  Ferris;1  it  is 


like  the  larva   of  Staphylinidae,  there  are 
nine   abdominal  segments  in  addition  to  a 


FIG.  108. — Scaphisoma  agari- 
cinum. Britain.  A 
Larva  (after  Perris)  ;  B 
perfect  Insect. 


very  short,  broad  pseudopod,  and  very  short 

cerci.      This  larva  feeds  on  agarics  ;  'it  goes  through  its  development 

in  about  three  weeks ;  unlike  the  adult  it  is  not  very  active. 
Fam.  25.    Synteliidae. — Antennae  davicorn,  with  very  large 

club  :  labium,  with  hypoglottis  and   the  parts  beyond  it,  exposed. 

Front  coxae  transverse.     Abdmni'ii  with  Jive  visible  ventral  segments, 

and  eight  or  nine  dorsal,  the  b/ixidfour  of  which  are  semi-corneous. 

This  family  includes  only  five  species;  its  clas- 
sification has  given  rise  to  much  difference 
of  opinion.  We  have,  after  consideration 
of  all  its  characters,  established  it  as  a 
distinct  family 2  allied  to  Silphidae.  The 
perfect  Insects  live  on  the  sap  running  from 
trees  :  but  nothing  else  is  known  of  their 
natural  history.  Like  so  many  others  of 
the  very  small  families  of  aberrant  Cole- 
optera,  it  has  a  very  wide  distribution ; 

PIG.  \Q9.-Syntelia   west-  fyntelia  being  found  in  Eastern  Asia   and 
modi.   Mexico.   (From  Mexico,  while    the   sub-family   Sphaeritides 
occurs,  as  a   single   species,  in  Europe   and 


f 


Biol.  Cent/:  Amer.) 


North  America.      The  earlier  instars  are  unknown. 
1  Larres  dc  Coldopteres,  1878,  p.  11.  pi.  i.         -  Biol.  Centr.  Amer.  Col.  ii.  pt.  i.  p.  438. 


230 


COLEOPTERA 


CHAP. 


Fam.  26.  Histeridae. —  Very  compact  beetles,  with  very  hard 
integument,  short,  bent  «»/<// //'<v,  with  a  very  compact  club:  no 
hypofjlottis.  Elytra  closely  applied  to  body,  but  straight  behind, 
leaving  fc'<>  xe/juients  exposed.  Abdomen  with  Ji  re  visible  ventral 
segments ;  vo'/A.  seven  <l<>rx«l  */>/i//ents,  all  liard.  Front  ce.'-<«- 
strongly  transverse,  hind  coxae  widely  separated.  The  extremely 
compact  form,  and  hard  integument,  combined  with  the  peculiar 
antennae — consisting  of  a  long  basal  joint,  six  or  seven  small 
joints,  and  then  a  very  solid  club  of  three  joints  covered  with 

minute  pubescence  —  render 
these  Insects  unmistakable.  The 
colour  is  usually  shining  black, 
but  there  are  numerous  depar- 
tures from  this.  The  way  in 
which  these  Insects  are  put 
together  so  as  to  leave  no  chink 
in  their  hard  exterior  armour 
when  in  repose,  is  very  remark- 


able. The  mouth  -  parts  are 
rather  highly  developed,  and 
the  family  is  entitled  to  a  high 
rank  ;  it  consists  at  present  of 
about  2000  species  ; l  in  Britain 
we  have  about  40.  The  larvae 
are  without  ocelli  or  labrum, 
FIG.  UQ.—Platysoma  depression.  Europe,  but  have  well-developed  mancli- 

A,    Larva    (after    Schiodte)  ;  B,    perfect    ,  ,  i  •     T 

insect.  oles,     the     second     and     third 

thoracic   segments  being  short, 

the  ninth  segment  of  the  abdomen  terminal,  with  two  distinctly 
jointed  cerci.2  Histeridae  are  common  in  dung,  in  carcases,  decay- 
ing fungi,  etc.,  and  some  live  under  bark — these  being,  in  the 
case  of  the  genus  Hololepta,  very  flat.  Some  are  small  cylinders, 
elaborately  constructed,  for  entering  the  burrows  of  'Insects  in 
wood  (Trypanaeus) ;  a  certain  number  are  peculiar  to  ants'  nests. 
Formerly  it  was  supposed  that  the  Insects  were  nourished  on 
the  decaying  substances,  but  it  is  now  believed,  with  good  reason, 
that  they  are  eminently  predaceous,  in  both  larval  and  imaginal 

The  family  was  monographed  by  the  Abbe  de  Marseul  in  Ann.  Soc.  cut.  France, 
1853-1862,  but  great  additions  have  been  made  since  then. 

2  For  characters  of  larvae  of  various  genera,  see  Ferris,  Larrcs,  etc.  p.  24. 


HISTERIDAE PHALACRIDAE — NITIDULIDAE 


231 


instars,  and  devour  the  larvae  of  Diptera,  etc.      The  relations  of  the 
ants'-nest  forms  to  the  ants  is  not  made  out,  but  it  is  highly  probable 
that   they  eat   the  ants'   larvae,  and  furnish  the  ants  with  some 
dainty  relish.      A  few  species  live  in  company  with  Termites. 
Fam.  27.   Phalacridae. — Body  very  compact;  elytra  entirely 

covering  it;  apical  joints  of  antennae  rather 
broader,  usually  long ;  front  coxae  globular ; 
posterior  coxae  contiguous ;  abdomen  with 
five  visible  ventral  segments ;  tarsi  five- 
jointed,  fourth  joint  usually  small  and 
obscure.  This  family  consists  entirely  of 
small  Insects  :  the  tarsal  structure  is  very 
aberrant,  and  is  also  diverse,  so  that  the 
student  may  without  careful  observation 
FIG.  ill.  —  Olibrus  bicolor.  pass  the  Insects  over  as  having  only  four- 

J°illted  toi;  theh>  structure,  so  far  _  as 
the  front  two  pairs  are  concerned,  being 
very  nearly  that  of  many  Fhytophaga.  The  larvae  live  in  the 
heads  of  flowers,  especially  of  the  flowers  of  Compositae.  Having 
bored  their  way  down  the  stems,  they  pupate  in  earthen  cocoons. 
Heeger  1  says  that  he  has  observed  in  favourable  seasons  six 
generations  ;  but  the  larvae  die  readily  in  unfavourable  seasons, 
and  are  destroyed  in  vast  numbers  when  the  meadows  are 
mowed.  Seven  years  ago  very  little  was  known  as  to  the  family, 
and  the  list  of  their  species  scarcely  amounted  to  100,  but  now 
probably  300  are  described.  They  occur  in  all  parts  of  the 
world ;  we  have  fourteen  in  Britain. 

Fam.  28.  Nitidulidae. — Antennae  with  a  three-jointed  club ; 
all  the  coxae  separated,  and  each  with  an  external  prolongation  ; 
tarsi  five-jointed,  the  fourth  joint  smaller  than  any  of  the  others ; 
abdomen  with  Jive  visible  plates.  These  Insects  are  numerous, 
about  1600  species  being  at  present  known;  in  many  of  them 
the  elytra  nearly  or  qiiite  cover  the  hind  body,  but  in  many 
others  they  are  more  or  less  abbreviated ;  in  this  case  the 
Insects  may  be  distinguished  from  Staphylinidae  by  the  form 
of  their  antennae,  and  the  smaller  number  of  visible  ventral  seg- 
ments. The  habits  are  very  varied,  a  great  many  are  found  on 
flowers,  others  are  attracted  by  the  sap  of  trees ;  some  live  in 
"We  have  about  90  species  in  Britain  ;  several  forms  of 

1  SB.  Ak.   JFien.  xxiv.  1857,  p.  330. 


232 


COLEOPTERA 


CHAP. 


A 


the  geneva,  Meligethes  and  Epuracn  are  among  the  most  abundant 
of  our  beetles.  Most  of  what  is  known  as  to  the  larvae  is 
due  to  Ferris  ;  several  have  been  found  living  in  flowers  ;  that 
of  Pria  haunts  the  flower  of  Xalaniim  dulcamara  at  the  junction 
of  the  stamens  with  the  corolla;  the  larva  of  Meligethes  aeneus 

sometimes  occasions  much  loss  by  prevent- 
ing the  formation  of  seed  in  cultivated 
Cruciferae,  such  as  Eape.  These  floricolous 
larvae  grow  with  great  rapidity,  and  then 
leave  the  flowers  to  pupate  in  the  ground. 
The  larva  of  Nitidula  lives  in  carcases, 
though  it  is  not  very  different  from  that 
of  Pria.  The  larva  of  tforuiiia.  lives  in 

FIG.  112.— Pria  dulcamarae.  fermenting  sap,  and  has  four   hooks  curv- 
Britain.    A,  Larva  (after  ing  upwards  at  the  extremity  of  the  body. 

Ferris)  ;  B,  perfect  Insect.    .„,"'  .  /-/   7  7     7  •   ", 

The  curious   genus   Uybocephalus   consists 

of  some  very  small,  extremely  convex  Insects  that  live  in  flowers 
in  Southern  Europe ;  they  have  only  four  joints  to  the  tarsi. 
The  perfect  Insects  of  the  group  Ipides  are  remarkable  from 
having  a  stridulating  organ  on  the  front  of  the  head.  The  classi- 
fication of  the  well-known  genus  Pihizophagus  has  given  rise  to 
much  discussion ;  although  now  usually  placed  in  Mtidulidae, 
\vc  think  it  undoubtedly  belongs  to  Cucujidae. 

Fam.  29.  Trogositidae. — Differs  from  Nitidulidae  in  the  struc- 
ture of  tin'  tarsi  ;  tliese  appear  f<>  lefour- 
jointed,  with  tlie  third  joint  similar  in 
size  and  form  to  the  jircccdi  nij  ;  tliei/ 
are,  however,  reaUt/  five-jointed,  an  eX- 
fre/rtC/1/  sit  oft  liana/  joint  lici/iif  /'/'/'Sent. 
Hind  COXae  continuous.  The  chili  of  cacli 
antenna  is  hilat,-,-all//  asymmetric,  and 
the  sensitive  surface  is  confined  to  certain 
parts  of  the  joints.  There  are  some  400 
or  500  species  of  Trogositidae,  but  nearly 
all  of  them  are  exotic.  The  larvae  (Fig. 
113,  A),  are  predaceous,  destroying  other  FIG.  \\$.—TemnocMa  coerulea. 

Europe.       A,     Larva     (after 

larvae  in   large  numbers,  and  it  is  pro-        p^-ris)  •.  B,  perfect  insect, 
bable    that    the    imagos    do    the    same. 

The  larva  of  Tcnelroides  (better  known  as  Troaoxita}  -inauritanica 
is  found  in  corn  and  flour,  and  is  said  to  have  sometimes  been  very 


1'oLVMORPHA TROGOSITIDAE COLYDIIDAE 


233 


injurious  by  eating  the  embryo  of  the  corn,  but  it  is  ascertained 
that  it  also  devours  certain  other  larvae  that  live  on  the  corn. 
This  beetle  has  been  carried  about  by  commerce,  and  is  now  nearly 
cosmopolitan.  Our  three  British  species  of  Trogositidae  repre- 
sent the  three  chief  divisions  of  the  family,  viz.  Xemosomides, 
Temnochilides,  Peltides  ;  they  are  very  dissimilar  in  form,  the 
Peltides  being  oval,  with  retracted  head.  It  is  doubtful  whether 
the  members  of  the  latter  group  are  carnivorous  in  any  of  their 
stages  ;  it  is  more  probable  that  they  live  on  the  fungi  they 
frequent.  Peltidae  stand  as  a  distinct  family  in  many  works.1 

Fam.  30.  Colydiidae.  —  Antennae  with  a  terminal  club,  tarsi 
four  -jointed,  none  of  the  joints  broad;  front  and  middle  coxae 
small,  globose,  embedded  ;  hind  coxae  transverse,  either  contiguous  or 
separated  ;  Jive  visible  ventral  segments,  several  of  which  have  no 
movement.  This  is  a  family  of  interest,  owing  to  the  great  diver- 
sity of  form,  to  the  extraordinary  sculpture  and  clothing  exhibited 
by  many  of  its  members,  and  to  the  fact  that  most  of  its  members 
are  attached  to  the  primitive  forests,  and  disappear  entirely 
when  these  are  destroyed.  We  have  fifteen  species  in  Britain, 
but  about  half  of  them  are  of  the  greatest  rarity.  There  are 
about  600  species  known  at  present;  Xew  Zealand  has  produced 

the  greatest  variety  of  forms  ;  the  forests 
of  Teneriffe  are  rich  in  the  genus  Tar- 
[iliius.  The  sedentary  lives  of  many  of 
these  beetles  are  very  remarkable  ;  the 
creatures  concealing  themselves  in  the 
crannies  of  fungus-covered  wood,  and 
scarcely  ever  leaving  their  retreats,  so 
that  it  is  the  rarest  circumstance  to  find 
them  at  any  distance  from  their  homes. 
Langelandia  anophthalma,  lives  entirely 
underground  and  is  quite  blind,  the 


FIG.  114.— 


crenata. 


Britain.      A,     Larva    (after    optic    lobes    bei          absent.        Some    Coly- 

erfect  Insect. 


Ferris)  ;  B,  perfect  Insect. 


the 


. 

diidae   are   more   active,  and    enter 

burrows  of  wood-boring  Insects  to  destroy  the  larvae  ((',> 
Few  of  the  larvae  are  known  ;  but  all  appear  to  have  the  body 
terminated  by  peculiar  hard  corneous  processes,  as  is  the  case 
with  a  great  variety  of  Coleopterous  larvae  that  live  in  wood.2 

1  Catalogue  of  Trogositidae,  by  Leveille,  in  Ann.  Soc.  cnt.  France,  1888,  p.  429. 
-  For  classification,  see  Sharp,  Biol.  Ccntr.  A  mcr.  Co7,  ii.  pt.  i.  1894,  p.  443. 


234 


COLEOPTERA 


CHAP. 


Fam.    31.    Rhysodidae. —  Tarsi   four-jointed  ;    mouth-parts 

covered,  l>y  the  I  a  rye  'inentum  ;  front  tibiae  •  notched  on  the  inner 
cd(i>\  This  family  consists  only  of  a  few  species,  but  is  found 
nc.-irly  all  over  the  world  in  the  warm  and  temperate  regions. 
In  many  of  their  characters  they  resemble  the  Adephaga,  but  are 
very  different  in  appearance  and  in  the  mouth.  The  larvae  are 
not  known.  Some  authorities  think  these  Insects  should  be 
placed  in  the  series  Aclephaga,1  but  it  is  more  probable  that  -they 
will  prove  to  be  amongst  the  numerous  aberrant  forms  of  Coleop- 
tera  that  approach  the  various  large  natural  series,  without 
really  belonging  to  them.  The  three  families,  Colydiidae,  Cucu- 
jidae,  and  Rhysodidae,  exhibit  relations  not  only  with  other 
families  of  the  Coleoptera  Polymorpha,  but  also  with  most  of  the 
great  series  ;  Adephaga,  Rhynchophora,  Fhytophaga,  and  Hetero- 
mera,  being  each  closely  approached. 

Fam.  32.  Cucujidae. —  Tarsi  Jive-  or  four-jointed,  the  first 
joint  often  short:  anteniia.e  sometimes  r/nlilied,  but  more  often 
<j_iiite  tli  i  ii  ut  the  tip;  front  cud  midille  coj.ae  deeply  embedded, 
globular,  but  n-ith  an,  an<inlar  prolongation  externally  ;  abdomen 
with  Jive  visible  rrnfral  segments,  all  movable.  This  family  and 

the  Cryptophagidae  are  amongst  the 
most  difficult  families  to  define ; 

3=* 

indeed  it  is  in  this  portion  of  the 
Clavicorns  that  an  extended  and 
thorough  study  is  most  urgently 
required.  The  Cucujidae  include  a 
great  diversity  of  forms ;  they  are 
mostly  found  under  the  bark  of  trees, 
and  many  of  them  are  very  fl;ii. 
Many  of  the  larvae  are  also  very 

t/  t/ 

Fro.  115.— Brontes plcmatus.    Britain,   flat,  but   Ferris   says  there  is  great 

A,    Larva;    B,    pupa;    C,    perfect     i-  -f        •        fV-pir    ^rnr-tnrp  •     thpv 

Insect.      (A  and  B  after  Perils.) 

are     probably    chiefly    carnivorous. 

There  are  about  400  species  described  ;  we  have  nearly  a  score  in 
Britain. 

The  family  Cupesidae  of  certain  taxonomists  must  be  at 
present  associated  with  Cucujidae,  though  the  first  joint  of  the 
tarsus  is  elongate. 

1  See  Ganglbauer,  Kaf.   Mitteleuropas,  i.  p.  ">:;().  as  well  as   Leconte  and  Horn 
Classification,  etc.,  p.  130. 


\ 


POLYMORPHA — CRYPTOPHAGIDAE HELOTIDAE         235 


A 


Fam.  33.  Cryptophagidae. — Front  and  middle  coxae  very 
small  and  deeply  embedded;  antennae  with  enlarged  terminal  joints ; 
lursi  five- jointed,  the  posterior  sometimes  in  the  male  only  four  - 
jointed;  abdomen  with  five  visible  ventral  segments,  capable  of 
in  <  >  r*' at  cut,  the  first  much  longer  than  any  of  the  others.  A  small 
family  composed  of  obscure  forms  of 
minute  size,  which  apparently  have 
mould-eating  habits,  though  very  little 
is  known  on  this  point,  and  several  of 
the  genera  (Anther ophagus,  Tclmatophi- 
lus)  are  found  chiefly  on  growing  plants, 
especially  in  flowers.  Although  the 
imago  of  Antherophagus  lives  in  flowers, 
yet  the  larva  has  only  been  found  in 
the  nests  of  bumble-bees ;  there  is  FIG.  ne.—Cryptophagvs  denta- 
reason  for  believing  that  the  imago 
makes  use  of  the  bee  to  transport 
it  from  the  flowers  it  haunts  to  the  nests  in  which  it  is  to 
breed ; x  this  it  does  by  catching  hold  of  the  bee  with  its 
mandibles  when  the  bee  visits  the  flower  in  which  the  beetle  is 
concealed.  It  is  strange  the  beetle  should  adopt  such  a  mode  of 
getting  to  its  future  home,  for  it  has  ample  wings.  We  must 
presume  that  its  senses  and  instinct  permit  it  to  recognise  the 
bee,  but  do  not  suffice  to  enable  it  to  find  the  bee's  nest.  Some 
of  the  larvae  of  the  genus  Cryptophagus  are  found  abundantly  in 
the  nests  of  various  wasps,  where  they  are  probably  useful  as 
scavengers,  others  occur  in  the  nests  of  social  caterpillars,  and  they 
are  sometimes  common  in  loose  straw ;  this  being  the  habitat  in 
which  Penis  found  the  one  we  figure. 

Fam.  34.  Helotidae. — Front  and  middle  coxal  cavities  round, 
with  scarcely  any  angular  prolongation  externally ;  all  the  coxae 
widely  separated ;  five  visible  ventral  segments,  all  mobile. 
The  Insects  of  this  family  are  closely  allied  to  Trogositidae 
and  Nitidulidae,  and  have  the  tarsal  structure  of  the  former 
family ;  but  the  Helotidae  are  .^different  in  appearance  from 
any  members  of  either  of  these  two  families,  and  are  readily 
distinguished  by  the  coxal  character.  They  are  frequently 
classified  with  the  Erotylidae,  from  which  they  differ  by  the 
differently  shaped  feet,  especially  by  the  diminished  basal  joint. 

1  Ferris,  Larves.  etc..  j>.  75. 


236  COLEOPTERA  CHAP. 

There  is  lint  one  genns,  and  for  a  long  time  only  two  or  three 
species  were  known,  and  were  great  rarities  in  collections  :  in 
the  last  few  years  the  number  has  been  raised  to  nearly  forty.1 
They  are  remarkable  beetles  with  oblong  form,  and  a  somewhat 
metallic  upper  surface,  which  is  much  sculptured,  and  possesses 
four  yellow,  smooth  spots  on  the  elytra.  According  to  Mr.  George 
Lewis  they  are  found  feeding  at  the  running  sap  of  trees,  but  the 
larvae  are  not  known.  Helotidae  are  peculiar  to  the  Indo-Malayan 
rr- inn  (including  Japan)  with  one  species  in  Eastern  Africa, 

Fam.  35.  Thorictidae. — Tarsi  five-jointed,  none  ofthejoinf* 
hr  o«d  ;  front  coxae  small,  rather  prominent,  but  not  at  oil  fr« /in- 
verse;  fire  visible  re/itn/J  jila/rx,  a/I  mobile;  mctasternn  »i  very 
situ rt  ;  antennae  xln>ff,irith  a  solid  dub.  This  little  family,  con- 
sisting of  the  genus  Thorirfnx,  appears  to  be  a  distinct  one, 
though  the  structure  has  only  been  very  imperfectly  studied.  It 
is  peculiar  to  the  Mediterranean  region,  where  the  species  live  in 
ants'  nests.  They  appear  to  be  on  terms  of  great  intimacy  with 
the  ants  ;  a  favourite  position  of  the  beetle  is  on  the  scape  of  the 
antenna  of  an  ant ;  here  it  hooks  itself  on  firmly,  and  is  carried 
about  by  the  ant.  Like  so  many  other  ants'-nest  beetles, 
Thorictidae  possess  tufts  of  golden  hair,  which  secrete  some 
substance,  the  flavour  of  which  is  appreciated  by  the  ants;  these 
tufts  in  Thorictidae  are  situated  either  at  the  hind  angles  of  the 
pronotmn,  or  on  the  under  surface  of  the  body  on  each  side  of  the 
breast ;  AVasmaim  thinks  that  when  the  beetles  are  riding  about, 

as  above  described,  the  ants  have  tln-n 
an  opportunity  of  getting  at  the  patches 
on  the  under  surface. 

Fam.  36.  Erotylidae.--ram  five- 
jointed,  but  'iritJi  the  fourth  -usual/ //  very 
small,  the  first  three  mure  or  less  brood 
a/id  i>id>e*ee///  beneath.  Antennae  xfro//>//f/ 
clubbed.  Front  and  middle  coxal  aeetu- 
"\T/  )  bula  round,  without  angulcw^prolongation 

FIG.  in.-Tritoma  Mpustulata.   externally;  fire  risible  ventral  segments. 

Erotyiiiiae.   Britain.   A,  Larva  This  is  now  a  large  and  important  family 
(after  Ferris) ;  B,  perfect  Insect.  .  ...       i  •    u 

of  about  1800  species,  but  it  is  chiefly 
exotic  and  tropical,  its  members  haunting   the  fungoid  growths 

1  Ritsema,  Catalogue  of  Helota,  Xotcs  Lcijdcn  J/HS.  xiii.  1891,  p.  223,  and  xv. 
1S93,  p.  UK). 


EROTYLIDAE--MYCETOPHAGIDAE  -  COCCINELLIDAE     237 

in  forests.  "We  have  only  six  species  in  Britain,  and  the  whole 
of  Europe  has  only  about  two  dozen,  most  of  them  insignificant 
(and  in  the  case  of  the  Dacnides  aberrant,  approaching  the 
Cryptophagidae  very  closely).  The  sub-family  Languriicles  (quite 
wanting  in  Europe)  consists  of  more  elongate  Insects,  with  front 
acetabula  open  behind  ;  they  have  different  habits  from  Eroty- 
lides  proper  ;  some  are  known  to  live  as  larvae  in  the  stems  of 
herbaceous  plants.  They  possess  a  highly  developed  stridulating 
organ  on  the  front  of  the  head.  The  Clavicorn  Polymorpha  are 
very  closely  connected  with  the  Phytophaga  by  Languriicles. 

Fam.  37.  Mycetophagidae.  —  Tarsi  four-joint  n],  slender,  the 
front  fed  of  the  male  only  three-jointed  ;  coxae  oml,  not  deeply 
embedded;  abdomen  icif/i  jin-  rentral  seg- 
ments, all  movable.  A  small  family,  of  in- 
terest chiefly  because  of  the  anomaly  in  the 
feet  of  the  two  sexes,  for  which  it  is  im- 
possible to  assign  any  reason.  The  species 
are  small,  uninteresting  Insects  that  live 
chiefly  on  Cryptogams  of  various  kinds, 
especially  in  connection  with  timber  ;  the 

larvae  being  also  found   there.      There  are  - 

FIG.    Jl8.  —  Litargus   bifas- 

about    a    dozen    species    in    Britain,    and        ciatu*.  Mycetophagidae. 


scarcely  100  are  described  from  all  the 
world.  The  DiphyUid.es,  placed  by  Leconte 
and  Horn  in  this  family,  seem  to  go  better  in  Cryptophagidae. 

Fam.  38.  Coccinellidae  (Lady  -birds}.  —  Tarsi  apparent!;/  three- 
jointed  ;  the  jirst  two  joints  pubescent  ln/nntli;  the  third  joint 
consisting  really  of  tivo  joints,  the  small  true  third  joint  being 
inserted  near  the  base  of  the  second  joint,  the  upper  surfun-  of  which 
is  grooved  to  receive  it.  Head  much  concealed  l>i/  the  thorax. 
Antennae  feebly  clubbed.  The  lady-birds  number  fully  2000 
species.  The  structure  of  their  feet  distinguishes  them  from 
nearly  all  other  Coleoptera-  except  Endomychidae,  which  are  much 
less  rotund  in  form,  and  have  larger  antennae.  One  genus  of 
Endomychids  —  Panomoea  —  bears,  however,  a  singular  resemblance 
to  lady-birds,  both  in  form  and  style  of  coloration.  Several 
species  of  Coccinellidae  are  remarkable  on  account  of  the 
numerous  variations  in  colour  they  present.  Coccinellidae 
frequently  multiply  to  an  enormous  extent,  and  are  of  great 
value,  as  they  destroy  wholesale  the  plant  -lice,  scale  -  Insects, 


238  COLEOPTERA 


CHAP. 


and  Acari  thar  are  so  injurious  to  cultivated  plants.  They 
also  eat  various  other  soft-bodied  Insects  that  attack  plants.  As 
thev  are  excessivelv  voracious,  and  are  themselves  sin<nilarlv 

*  t,  t 

free  from  enemies  and  multiply  with  great  rapidity,  all  these 
features  of  their  economy  render  them  of  inestimable  value  to  the 
agriculturist  and  horticulturist.  The  species  of  the  sub-faniily 
Epilachnides  feed  on  plants,  and  one  or  two  are  occasionally  in- 
jurious. The  body-fluid  of  Coccinellidae  has  an  unpleasant  odour 
and  taste.  Many  lady-birds  have  the  power  of  exuding,  when 
disturbed,  small  quantities  of  a  yellow  fluid.  Lutz  has  shown  that 
this  is  not  a  special  secretion,  but  an  exudation  of  the  fluid  of 
the  body  that  takes  place  through  a  small  orifice  at  the  tip  of 
the  tibia,  from  pressure  caused  by  contraction  of  the  body  and  limb.1 
The  larvae  are  much  more  active  than  beetle-larvae  usually 
are,  and  many  of  them  are  very  conspicuous  when  running  about 
on  plants  to  hunt  their  prey.  They  usually  cast  their  skins 
three  times,  and  sometimes  concomitantlv  change  a  good  deal  in 

«• 

colour  and  form  :  the  larval  life  does  not  usuallv  exceed  four  or 

• 

five  weeks :  at  the  end  of  which  time  the  larva  suspends  itself 
by  the  posterior  extremitv.  which  is  slued  bv  a  secretion  to  some 

*  -L  «.     *  v 

object ;  the  larval  skin  is  pushed  back  to  the  anal  extremity, 
disclosing  the  pupa  :  this  differs  in  several  respects  from  the 
usual  pupa  of  beetles :  it  is  harder,  and  is  coloured,  frequently 
conspicuously  spotted,  and  dehisces  to  allow  the  escape  of  the 
beetle,  so  that  the  metamorphosis  is  altogether  more  like  that  of 
Lepidoptera  than  that  of  Coleoptera.  There  is  much  variety  in 
the  larvae ;  some  of  them  bear  large,  complexly-spined,  projections : 
those  of  the  group  Scymnites  have  small  depressions  on  the 
surface,  from  which  it  has  been  ascertained  that  waxy  secre- 
tions exude  :  but  in  Scymnus  minimus  no  such  excretions  are 
formed.  Certain  species,  when  pupating,  do  not  shuffle  the  skin  to 
the  extremitv  of  the  bodv,  but  retain  it  as  a  covering  for  the 

e.  t,     '  O 

pupa.  The  larvae  that  feed  on  plants  are  much  less  active  than 
the  predaceous  forms.  "\Ve  are  well  supplied  with  Coccinellidae 
in  Britain,  forty  species  being  known  here. 

The  systematic  position  of  Coccinellidae  amongst  the  Coleoptera 
has  been  for  long  a  moot  point.  Formerly  they  were  associated 
with  various  other  beetles  having  three-jointed,  or  apparently 
three-jointed,  feet,  as  a  series  with  the  name  Trimera,  or 

1  Z<jol.  virt:.  sviii.  1895.  p.  244. 


IXELLIDAE EXDOMYCHIDAE MYCETAEIDAE       2 

I'-'-udotrimera.      But  :..-  _      -rally  placed  in  the  Clavicorn 

ar   Endoniychidae,  rhoeff   has   recently  made   con- 

morphological   stu«:  the  male  genital  organs  of 

i,  and   as   the    result,   he    concludes   that  Coccinellidae 
radically    from    all    other     Coleoptera     as    regards    these 
-  •_  ictures,  and  he  therefore  treats  them  as  a  distinct  series  or 
sub-order,  termed  Siphonophora.      The  genus  Lithophilus  has  been 
red  doubtfully  a  member  of  Coccinellidae,  as  the  tarsi 
-sess  only  in  a  slight  degree  the  shape   characteristic  of  the 
.ilv  :   Verhoeff  finds  that  they  are  truly  Coccinellidae,  forming 
a  distinct  division,  Lithophilini:  and  our  little  species  of  Coccidula, 
which   have  somewhat  the  same  appearance  as  Lithophilini,  he 
its  as  another  separate  group,  Coceidulini. 
Fam.  39.  Kndomychidae.1- 

'  tico  joints  broad,  the  terminal  joint  elongate  ;  at  the  base  of 

terminal  joint  there  is,  however,  a,  very  small  joint,  so  that  the 

<i  are  pseudotetramerous  ;  antennae  rather  large,  with  a  large 

•' ;  labium  not  at  all  retracted  behind  the  mentum;  front  and 

hlle  coxae  globose  ;  abdomen  with  five  movable  ventral  segments, 

and,  a  sixth  more  or  less  visible  at  the  tip.      This  family  includes 

a  considerable  diversity  of  elegant  Insects  that  frequent  fungoid 

growths  on  wood.      It  comprises  at  present  fully  500  species,  but 

nearly  the  whole    of  them   are   exotic,  and  inhabit  the    tropical 

forests,     "\Ve  have  only  two  British  species,  both  of  which  are 

now    rarities,    but    apparently    were    much    commoner    at    the 

beginning  of  the  century.      The  larvae  are 

broader  than  is  usual  in  Coleoptera :  very 

few,  however,  are  known. 

Fam.    40.    Mycetaeidae. — T  • 

'.  the  first  two  joints  not  very  different 
third,    usually   slender;    abdomen 
n-ve  visible  ventral  segments,  which  are 
~le;  front  and   middle  coxae  globular.         A  B 

The  little  Insects  composing  this  familv  are  FIG.  ii9.--J/y«*a«i 

.Britain.      A.    La: 

many  placed  as  a   division  of  Endomy-        ^after  Bii^  r.  :  B?  per- 
chidae,  and  Verhoeff  is  of  opinion  that  the 
_     up  is  an  altogether  artificial  one ;.  but  we  think,  with  Duval, 
it   makes    matters    simpler   to    separate    them.      There   are  only 

1  G- :  -  :.  Monographie  dcr  E>id*>myehiden.  Leipzig.  -"-    ".         |          .Since  this 

work  was  published,  the  species  known  have  been  multiplied  two  or  three  times. 


24-O 


COLEOPTERA 


CHAP. 


some  forty  or  fifty  species,  found  chiefly  in  Europe  and  North 
America.  We  have  three  in  Britain ;  one  of  these,  Myeetaea 
hi /-fa  is  very  common,  and  may  be  found  in  abundance  in  cellars 
in  the  heart  of  London,  as  well  as  elsewhere  ;  it  is  said  to  have 
injured  the  corks  of  wine-bottles,  and  to  have  caused  leakage 
of  the  wine,  but  we  think  that  it  perhaps  only  increases  some 
previous  deficiency  in  the  corkage,  for  its  natural  food  is  fungoid 
matters.  The  larva  is  remarkable  on  account  of  the  clubbed 
hairs  at  the  sides  of  the  body. 

Fam.  41.  Latridiidae. — Tarsi  three-jointed;  anterior 
cavities  round,  not  prolonged  externally;  alxlomen  with  j!  rr 
innl  mobile  ventral  *</j inputs.  Very  small  Insects,  species  of  which 
are  numerous  in  most  parts  of  the  world,  the  individuals  being 
sometimes  very  abundant.  The  larvae  (Fig.  120,  A)  are  said  by 
IVrris  to  have  the  mandibles  replaced  by  fleshy  appendages.  The 
pupa  of  L*it  r'nl  i  us  is  remarkable,  on  account  of  the  numerous  long 
hairs  with  heads  instead  of  points;  the  larva  of  Cni-firm-ia  is 
very  like  that  of  Lai  rid  ins,  but  some  of  the  hairs  are  replaced  by 
obconical  projections.  The  suit-family  Monotomides  is  by  many 
treated  as  a  distinct  family  ;  they  have  the  elytra  truncate  behind, 
exposing  the  pygidium,  and  the  coxae  are  very  small  and  very 
deeply  embedded.  Most  of  the  Latridiidae  are  believed  to  live  on 
fungoid  matters ;  species  of  Monotoma 
live  in  ants'  nests,  but  probably  have 
no  relations  with  the  ants.  A  few 
species  of  Latridiides  proper  also  main- 
tain a  similar  life;  Coluocera formicaria 
is  said  to  be  fond  of  the  stores  laid  up 
by  ApJiaenogaster  structor  in  its  nests. 
About  700  species  are  now  known; 
scarcely  any  of  the  individuals  are  more 

than   one-tenth    of   an    inch   long.      We  FIG.  120. — Lutrui.ius  mi  nut  n^. 
have  about  40  species  in  Britain.      The 
North  American  genus  Stephostethus  has 
the  prosternum  constructed  behind  the  coxae,  somewhat   in   the 
same  manner  as  it  is  in  the  Ehynchophorous  series  of  Colenptem. 

Fam.   42.    Adimeridae. — Tarsi   apjix/ri/iir  <>/i///   tico-jointed, 
I  basal  joint  and  an  ch»if/afe  claw-bearing  joint,  but  between 


tin*   two   tin-re  are  two  very  small  joints.      This    family  consists 
only   of  the   American   genus   Adi/ncrus;   nothing  is   known   of 


POLYMORPHA DERMESTIDAE 


241 


the    life -history    of   these    small    Insects.        They    are    of    some 
interest,  as  this  structure  of  the  foot 
is  not  found  in  any  other  beetles. 

Fam.  43.  Dermestidae. — Tarsi 
jive-jointed;  antennae  usually  short, 
with  the  club  frequently  very  large 
in  proportion,  and  with  the.  under 
side  of  the  thorax  hearing  a.  hollow 
for  its  reception.  Front  coxae  rather 
long,  oblique:  hind  coxa  formed  to 
receive  the  femur  when  in  repose. 
A  family  of  300  or  400  species  of 
small  or  moderate-sized  beetles  ;  the  FlG-  121.  —  Adimerus  setosvs.  Adi- 

„  ,,  1-1  meridae.     A,  the  Insect  ;    B,    one 

SUrlace,    usually    Covered     With     hlie          foot  more  enlarged.    Mexico.    From 

hair,  forming  a  pattern,  or  with  BioL  Centr-  Amer-  CoL  ij-  P*-  *• 
scales.  By  turns,  the  position  of  which  has  long  been  disputed, 
has  now  been  placed  in  this  family ;  it  has  a  more  imperfectly 
formed  prosternum,  and  the  third  and  fourth  joints  of  the  tarsi 
are  prolonged  as  membranous  lobes  beneath  ;  the  hind  coxae  leave 
the  femora  quite  free.  Dermestidae  in  the  larval  state  nearly  all 
live  on  dried  animal  matter,  and  are  sometimes  very  destructive  ; 
some  of  them  totally  destroy  zoological  collections.  They  are 

very  remarkable  on  account  of  the  complex 
clothing  of  hairs  they  bear ;  they  have  good 
powers  of  locomotion,  and  many  of  them 
have  a  peculiar  gait,  running  for  a  short 
distance,  then  stopping  and  vibrating  some 
of  their  hairs  with  extreme  rapidity.  They 
exhibit  great  variety  of  form.  Many  of 
them  are  capable  of  supporting  life  for  long 
periods  on  little  or  no  food,  and  in  such 
cases  moult  an  increased  number  of  times  : 
pupation  takes  place  in  the  larval  skin. 
Anthrenus  fasciatus  has  been  reared  in  large 
numbers  on  a  diet  of  dried  horse-hair  in 
furniture.  The  young  larva  of  this  species 
observed  by  the  writer  did  not  possess 
the  remarkable,  complex  arrangement  of  hairs  that  appeared 
when  it  was  further  grown.  The  most  curious  of  Dermestid 
larvae  is  that  of  Tiresias  serra,  which  lives  amongst  cobwebs  in 

VOL.  VI  R 


FIG.   122.  —  Tiresias  serra 
Larva.     New  Forest. 


242  COLEOPTERA  CHAP. 

old  wood,  and  probably  feeds  on  the  remains  of  Insects  therein, 
perhaps  not  disdaining  the  cobwebs  themselves.  Attention  has 
been  frequently  called  to  the  hairs  of  the  larvae  of  these  Insects, 
but  they  have  never  been  adequately  discussed,  and  their  function 
is  quite  unknown. 

Fam.  44.  Byrrhidae  (Pill-beetles). — Oval  or  round, convex  beetles; 
tarsi  five-jointed,  front  coxae  not  exserted,  transverse ;  hind  coxa 
shic/di/iif  the  retracted  femur.  The  ivhole  of  the  appendages 
capable  of  a  complete  apposition  to  the  body.  Although  a  small 
family  of  only  200  or  300  species,  Byrrhidae  are  so  hetero- 
geneous that  no  characteristic  definition  that  will  apply  to 
all  the  sub-families  can  be  framed.  Very  little  is  known  as  to 
their  life -histories.  Byrrhus  pilula  is  one  of  our  commonest 
beetles,  and  may  be  found  crawling  on  paths  in  early  spring 
even  in  towns ;  it  moves  very  slowly,  and  when  disturbed,  at 
once  contracts  the  limbs  so  completely  that  it  looks  like  an 
inanimate  object.  The  larva  is  cylindrical,  soft ;  the  prothoracic 
and  last  two  abdominal  segments  are  larger  than  the  others, 
the  last  bearing  two  pseudopods ;  its  habits  are  unknown,  and 
110  good  figure  exists  of  it. 

The  chief  groups  of  Byrrhidae  are  Nosodendrides,  Byrrhides 
(including  Amphicyrtides),  Limnichides,  and  Chelonariides.  The 
first  consists  of  species  frequenting  the  exuding  sap  of  trees ; 
they  have  an  unusually  large  mentuni,  abruptly  clubbed  antennae, 
and  the  head  cannot  be  retracted  and  concealed.  The  genus 
yosw/,'>it/i'i'ii  serins  to  be  distributed  over  a  large  part  of  the 
world.  The  Byrrhides  have  the  antennae  gradually  thicker 
towards  the  tip,  the  mentum  small,  and  the  head  and  thorax  so 
formed  that  the  former  can  be  perfectly  retracted.  The  species 
are  rather  numerous,  and  are  found  in  the  northern  and  anti- 
]  MX  leal  regions,  being  nearly  completely  absent  from  the  tropics. 
The  Limnichides  are  minute  Insects  living  in  very  moist  places : 
they  have  small  delicate  antennae,  which  are  imperfectly  clubbed. 
The  group  is  very  widely  distributed. 

The  Chelonariides  are  a  very  peculiar  form  of  Coleoptera  : 
oval  Insects  of  small  size  with  the  prothorax  so  formed  that  the 
head  can  be  withdrawn  under  (rather  than  into)  it,  and  then 
abruptly  inflexed,  so  that  the  face  then  forms  part  of  the  under 
surface  :  the  antennae  have  the  basal  three  joints  thicker  than 
the  others ;  these  being  not  in  the  least  clubbed,  but  having  the 


POLYMORPHA  243 


joints  so  delicately  connected  that  the  organs  are  rarely  un- 
mutilated.  The  modifications  of  the  head  and  prothorax  are 
quite  unlike  those  of  other  Byrrhidae,  and  if  the  Chelonariides 
do  not  form  a  distinct  family,  they  should  be  associated  with 
Dascillidae.  -Nothing  is  known  as  to  the  earlier  stages.  They 
are  chiefly  tropical  Insects,  though  one  species  is  found  in  North 
America. 

Fam.  45.  Cyathoceridae — Minute  Insects  of "broad  form ;  parts 
of  the  mouth  concealed ;  antennae  four-jointed ;  tarsi  not  divided 
into  joints  ;  prosternum  small.  The  only  species  of  this  aberrant 
family,  Cyathocerus  horni,  has  been  found  in  Central  America. 
Nothing  is  known  as  to  its  life-history. 

Fam.  46.  Georyssidae. — -Antennae  short,  dulled ;  tarsi  four- 
jointcd;  prosternum  very  small;  front  coxae  exserted,  but  not 
contiguous.  There  are  about  two  dozen  species  of  these  small 
beetles  known.  Our  British  Georyssus  pygmaeus  lives  in  extremely 
wet  places,  and  covers  itself  with  a  coating  of  mud  or  fine  sand 
so  that  it  can  only  be  detected  when  in  movement.  Nothing 
further  is  known  as  to  its  life-history  or  habits.  Members  of 
the  genus  have  been  detected  in  widely- separated  parts  of  the 
globe. 

Fam.  47.  Heteroceridae. — Labrum  and  mandibles  projecting 
forwards;  antennae  short,  the  terminal  seven  joints  broad  and  short, 
forming  a  sort  of  broad  serrate  club  ;  legs  armed  u'ith  stout  spines ; 
fi/rsi  four-jointed.  The  Heteroceridae  are  small  beetles  covered 
with  very  dense  but  minute  pubescence  ;  they  live  in  burrows 
among  mud  or  sand  in  wet  places,  and  are  found  in  many  parts 
of  the  world.  They  possess  a  stridulating  organ  in  the  form 
of  a  slightly  elevated  curved  line  on  each  side  of  the  base  of  the 
abdomen,  rubbed  by  the  posterior  femur.  The  larvae  live  in  the 
same  places  as  the  beetles ;  they  have  well-developed  thoracic- 
legs,  the  mandibles  are  porrect,  the  three  thoracic  segments 
rather  large,  and  the  body  behind  these  becomes  gradually 
narrower ;  they  are  believed  to  eat  the  mud  amongst  which 
they  burrow.  "We  have  seven  British  species  of  Hetero- 
ceridae. 

Fam.  48.  Parnidae. — Prosternum.  distinct  in  front  of  the  coxae, 
iixinillil  i-lniii'iate,  behind  forming  a  process  receirnJ  into  a  definite, 
cavity  on  the  mesosternum ;  head  retractile,  1 1/ c  ///<»/////  protected 
by  the  prosternum.  Tarsi  Jive -jointed,  term  i /ml  joint  long. 


244  COLEOPTERA  CHAP. 

Although  the  characters  of  these  Insects  are  not  very  different 
from  those  of  Byrrhidae,  of  Dascillidae,  and  even  of  certain 
Elateridae,  there  is  practically  but  little  difficulty  in  distinguish- 
ing Parnidae.  They  are  of  aquatic  habits,  though  many,  in  the 
perfect  state,  frequently  desert  the  waters.  There  are  about 
300  or  400  species  known,  but  the  family  is  doubtless  more 
extensive,  as  these  small  beetles  attract  but  little  notice.  There 
are  two  groups: — 1.  Parnides,  in  which  the  front  coxae  have  a  con- 
siderable transverse  extension,  the  antennae  are  frequently  short 
and  of  peculiar  structure,  and  the  body  is  usually  clothed  with 
a  peculiar,  dense  pubescence.  2.  Elmides,  with  round  front  coxae, 
a  bare,  or  feebly  pubescent  body,  and  simple  antennae.  Parnus 
is  a  genus  commonly  met  with  in  Europe,  and  is  less  aquatic  in 
habits  than  its  congeners ;  it  is  said  to  enter  the  water  carrying 
with  it  a  coating  of  air  attached  to  its  pubescence.  Its  larvae 
are  not  well  known ;  they  live  in  damp  earth  near  streams,  and 
are  said  to  much  resemble  the  larvae  of  Elateridae.  Potamophilus 
urii niinatus  has  a  very  interesting  larva,  described  by  Dufour ;  it 
lives  on  decaying  wood  in  the  Adour.  It  is  remarkable  from 
the  ocelli  being  arranged  so  as  to  form  an  almost  true  eye  on 
each  side  of  the  head;  there  are  eight  pairs  of  abdominal 
spiracles,  and  also  a  pair  on  the  mesothorax,  though  there  are 
none  on  the  pro-  or  meta-thorax ;  each  of  the  stigmata  has  four 
elongate  sacs  between  it  and  the  main  trachea!  tube  ;  the  body 
is  terminated  by  a  process  from  which  there  can  be  protruded 
bunches  of  filamentous  branchiae.  The  larvae  of  Macronychus 
quadrituberculatus  is  somewhat  similar,  though  the  features  of  its 
external  structure  are  less  remarkable.  The  Elmides  live  attached 
to  stones  in  streams ;  the  larva  is  rather  broad,  fringed  at  the 
sides  of  the  body,  and  bears  behind  three  elegant  sets  of  fine 
filamentous  branchiae.  The  North  American  genus  Psephrm/x 
is  placed  in  Parnidae,  though  instead  of  five,  the  male  has 
seven,  the  female  six,  visible  ventral  segments ;  the  larva  is 
elliptical,  with  dilated  margins  to  the  body.  Friederich,  has 
given,1  without  mentioning  any  names,  a  detailed  account 
of  Brazilian  Parnid  larvae,  that  may  perhaps  be  allied  to 
Psephenus. 

Fam.  49.  Derodontidae. — Ta/'si  //Vr-/W///<v/,   x/mJer,  fourth 
joint  rather  small ;  front  cover  prominent  ami   transversely  pro- 

1  Stettin,  cnt.  Zeit.  xlii.  1881,  pp.  104-112. 


POLYMORPHA — DERODONTIDAE CIOIDAE 


245 


lonycd  ;  middle  coxae  small;  abdomen  with  five  visible  segments, 
all  mobile ,  the  first  not  elongated.  One  of  the  smallest  and  least 
known  of  the  families  of  Coleoptera ;  it 
consists  of  four  or  five  species  of  small 
Insects  of  the  genera  Derodontus  and 
Peltasticta,  found  in  Xorth  America, 
Europe,  and  Japan.  The  distinction  of  the 
family  from  Cleridae  is  by  no  means  cer- 
tain ;  our  European  Laricobius  apparently 
possessing  characters  hut  little  different. 
Nothing  is  known  as  to  the  life-histories. 
Fam.  50.  Cioidae. — Small  or  minute 
beetles;  antennae  short,  terminal  joints 
thicker;  tarsi  short,  four-jointed  ;  anterior 
and  middle  coxae  small,  oval,  deeply  em- 


c 


FIG.  123. — Derodontus  macu- 

bedded  ;    abdomen   with  Jim    ventral    sey-       iatus_    North  America. 

ments,  all  mobile.      The  position  of  these 

obscure  little  Insects  seems  to  be  near  Colydiidae  and  Crypto- 

phagidae,  though  they  are  usually 
placed  near  Bostrichidae.  So  far  as 
known,  they  all  live  in  fungi,  or  in 
wood  penetrated  by  fungoid  growths. 
The  cylindrical  larvae  live  also  in 
similar  matter  ;  they  usually  have  the 
body  terminated  behind  by  one  or  two 
huoks  curved  upwards;  that  of  Cis 
nielliei  (Fig.  124)  has,  instead  of  these 
hooks,  a  curious  chitinous  tube.  About 
300  species  of  the  family  are  now 
known ;  a  score,  or  so,  occurring  in 
Britain.  The  Hawaiian  Islands  have 
a  remarkably  rich  and  varied  fauna  of 

FIG.   l-2-i.—Cis  melliei.      Martin-    Cioiclae. 

ique.     A,  Perfect  Insect ;    B  j.  51    SpMndidae. This  family 

pupa  ;  C,   larva  ;  D,   terminal 

portion   of   body   of    larva,   of   half   a    dozen   species    of    rare  and 

(After  Coquerel.)  gmdl    Ingects>   Differs    from    Cioidae    by 

the  tarsi  being  five-jointed  at  any  rate  on  the  front  and  middle 
feet,  opinions  differing  as  to  whether  the  number  of  joints  of  the 
hind  tarsi  is  four  or  five.  These  Insects  live  in  fungi  growing 
in  wood,  e.g.  Reticularia  hortensis,  that  are  at  first  pulpy  and 


246 


COLEOPTERA 


CHAP. 


afterwards  become  powder.  The  larvae  of  both  of  our  British 
genera,  Sphindus  and  Aspidipliorus,  have  been  described  by 
Ferris,  who  considers  them  allied  to  the  fungivorous  Silphidae 
and  Latridiidae.  The  systematic  position  of  these  Insects  has 
been  the  subject  of  doubt  since  the  days  of  Latreille. 

Fam.  52.  Bostrichidae  (Apatidae  of  some  authors). — Tarsi 
five-jointed,  but  the  first  joint  very  short  and  imperfectly  separated 

from  the  second;  front  coxae  prominent,  con- 
tiguous, very  little  extended  transversely ;  five 
visible  ventral  segments.  The  Bostrichidae 
attack  dry  wood,  and  sometimes  in  such 
large  numbers  that  timber  is  entirely 
destroyed  by  them ;  most  of  them  make 
cylindrical  burrows  into  the  wood.  The 
larvae  have  the  posterior  part  of  the 
body  incurved,  and  resemble  the  wood- 
boring  larvae  of  Anobiidae  rather  than 
the  predaceous  larvae  of  Cleridae.  We 
follow  Leconte  and  Horn  in  placing 
Lyctides  as  a  division  of  Bostrichidae ; 
although  differing  very  much  in  appear- 

FIG.  125.-Apate  capudna.   ance>  the7  have  similar  habits  and  larvae. 
Europe.    A,  Larva  (after  The   typical   Bostiichides   are    remarkable 

Ferris)  ;    B,     pt-rt'ect    III-     n        ,  i      •  •    ,          n 

sect.  tor  their  variety  of  sculpture  and  for  the 

shapes  of  the  posterior  part  of  the  body : 

this  part  is  more  or  less  conspicuously  truncate,  and  furnished 
with  small  prominences.  Dinapate  u-riyhtii,  found  in  the  stems 
of  a  species  of  Yucca  in  the  Mojave  desert  of  California,  attains 
a  length  of  nearly  two  inches  ;  its  larva  is  extremely  similar  to 
that  of  A.  capudna,  Some  of  the  forms  (Plionapate}  stridulate 
in  a  manner  peculiar  to  themselves,  by  rubbing  the  front  leg 
against  some  projections  at  the  hind  angle  of  the  prothorax.  Up- 
wards of  200  species  of  the  family  are  known.  In  Britain  we 
have  only  four  small  and  aberrant  forms. 

Fam.  53.  Ptinidae. — Tarsi  five-jointed,  first  joint  not  reduced 
in  size,  often  longer  than  second ;  front  and  middle  coxae  small, 
not  transversely  extended,  the  former  sliglitly  prominent;  five 
visible  ventral  segments;  prostenuuii  very  short.  Here  are  in- 
cluded two  sub  -  families,  Ptinides  and  Anobiides ;  they  are 
considered  as  distinct  families  by  many  authors,  but  in  the 


POLYMORPHA — PTINIDAE 


247 


FIG.  126.—"  Biscuit-weevil." 
A  nobium  pan  iceum. 


present  imperfect  state  of  knowledge  l  it  is  not  necessary  to  treat 
them  separately.  Ptinidae  are  sometimes  very  destructive  to  dried 
animal  matter,  and  attack  specimens  in 
museums  ;  Anobiides  bore  into  wood,  and 
apparently  emerge  as  perfect  Insects  only 
for  a  very  brief  period;  Anobiutn  ($ito- 
il  1-1  •/>«*)  paniceum  is,  however,  by  no  means 
restricted  in  its  tastes ;  it  must  possess 
extraordinary  powers  of  digestion,  as  we 
have  known  it  to  pass  several  consecu- 
tive generations  on  a  diet  of  opium  ;  it 
has  also  been  reported  to  thrive  on 
tablets  of  dried  compressed  meat ;  in 
India  it  is  said  to  disintegrate  books ;  a 
more  usual  food  of  the  Insect  is,  how- 
ever, hard  biscuits ;  weevilly  biscuits  are 
known  to  every  sailor,  and  the  so-called  "  weevil "  is  usually 
the  larva  of  A.  paniceum  (Fig.  127,  B).  In  the  case  of  this  Insect 
we  have  not  detected  more  than  one  spiracle  (situate  on  the 
first  thoracic  segment) ;  the  other  known  larvae  of  Anobiides  are 
said  to  possess  eight  abdominal  spiracles.  The  skeleton  in  some 


FIG.  127.  —Early 
stages  of  Anobium 
paniceum.  A,  Eggs, 
variable  in  form  ; 
B,  larva  ;  C,  pupa  ; 
D,  asymmetrical 
processes  terminat- 
ing body  of  pupa. 
[This  larva  is  pro- 
bably the  "book- 
worm "  of  librar- 
ians]. 


of  this  sub-family  is  extremely  modified,  so  as  to  allow  the 
Insects  to  pack  themselves  up  in  repose  ;  the  head  is  folded  in 
over  the  chest,  and  a  cavity  existing  on  the  breast  is  thus  closed 
by  the  head ;  in  this  cavity  the  antennae  and  the  prominent 
mouth-parts  are  received  and  protected ;  the  legs  shut  together 

1  It  is  probable  that  we  do  not  know  more  than  the  fiftieth  part  of  the  existing 
species,  most  of  which  lead  lives  that  render  them  very  difficult  to  find. 


248  COLEOPTERA  CHAP. 

in  an  equally  perfect  manner,  so  that  no  roughness  or  chink 
remains,  and  the  creature  looks  like  a  little  hard  seed.  Anobium 
striatuin  is  a  common  Insect  in  houses,  and  makes  little  round 
holes  in  furniture,  which  is  then  said  to  be  "  worm-eaten."  A. 
(Xestoln.tnn*)  tessellatum ,  a  much  larger  Insect,  has  proved  very 
destructive  to  beams  in  churches,  libraries,  etc.  These  species 

are  the  "death-watches"  or  "greater 
death-watches  "  that  have  been  associated 
with  the  most  ridiculous  superstitions 
(as  we  have  mentioned  in  Volume  V., 
when  speaking  of  the  lesser  death- 
watches,  or  Psocidae).  The  ticking  of 
these  Insects  is  really  connected  with  sex, 
and  is  made  by  striking  the  head  rapidly 
against  the  wood  on  which  the  Insect 

O 

is  standing. 

The  very  anomalous   genus  Ectreplies 
FIG.  128. — Ectrepkes  kingi.  J 

West      Australia.        (After    (Fig.    128)     is     found    ill     ants'    liests     ill 

Westwood.)  Australia.     Westwood  placed  it  in   Tti- 

nidae.  Wasmann  has  recently  treated  it  as  a  distinct  family, 
Ectrephidae,  associating  it  with  Polyplocotes  and  Diplocotes,  and 
treating  them  as  allied  to  Scydmaenidae. 

Fam.  54.  Malacodermidae. — Kecen  (or  even,  eiglif)  visible  ven- 
tral segments,  tlie  lasal  one  not  co-adapted  in  form  with  the  coxae  ; 
tarsi  Jive-jointed.  Integument  softer  than  usual,  the  ^orfe  of  tJie 
body  not  accurately  co-ad  xpti-d.  This  important  family  includes 
a  variety  of  forms:  viz.  Lycides,  Drilides,  Lampyrides,  Telepho- 
rides ;  though  they  are  very  different  in  appearance,  classifiers 
have  not  yet  agreed  on  separating  them  as  families.  Of  these 
the  Lampyrides,  or  glow-worms,  are  of  special  interest,  as  most 
of  their  members  give  off  a  phosphorescent  light  when  alive ;  in 
many  of  them  the  female  is  apterous  and  like  a  larva,  and  then 
the  light  it  gives  is  usually  conspicuous,  frequently  much  more 
so  than  that  of  its  mate  ;  in  other  cases  the  males  are  the  most 
brilliant.  The  exact  importance  of  these  characters  in  the  crea- 
tures' lives  is  not  yet  clear,  but  it  appears  probable  that  in  the 
first  class  of  cases  the  light  of  the  female  serves  as  an  attraction 
to  the  male,  while  in  the  second  class  the  very  brilliant  lights  of 
the  male  serve  as  an  amusement,  or  as  an  incitement  to  rivalry 
amongst  the  individuals  of  this  sex.  The  well-known  fire-Hies 


V 


MALACODERMIDAE FIRE-FLIES — GLOW-WORMS 


249 


(Ludol(C)  of  Southern  Europe  are  an  example  of  the  latter  con- 
dition. They  are  gregarious,  and  on  calm,  warm  nights  crowds 
of  them  may  be  seen  moving  and  sparkling  in  a  charm- 
ing manner.  These  individuals  are  all,  or  nearly  all,  males ; 
so  rare  indeed  is  the  female  that  few  entomologists  have  even 
noticed  it.  The  writer  once  assisted  in  a  large  gathering  of 
Luciola  italica  in  the  Yal  Anzasca,  which  consisted  of  many 
hundreds  of  specimens ;  all  of  those  he  caught,  either  on  the 
wing  or  displaying  their  lights  on  the  bushes,  were  males,  but 
he  found  a  solitary  female  on  the  ground.  This  sex  possesses 
ordinary,  small  eyes  instead  of  the 
large,  convex  organs  of  the  male, 
and  its  antennae  and  legs  are 
much  more  feeble,  so  that  though 
provided  with  elytra  and  wings 
it  is  altogether  a  more  imper- 
fect creature.  Emery  has  given 
an  account  of  his  observations 
and  experiments  on  this  Insect, 
but  they  do  not  give  any  clear 
idea  as  to  the  exact  function  of 
the  light.1  In  our  British  glow- 
worm the  female  is  entirely  apter- 
ous  hence  the  name  gloW-WOrm  FIG.  129.—  Phengodes  hieronymi.  Cor- 
doba, South  America.  (After  Haase.) 
A.  Male  ;  B,  female.  I,  I,  Positions 
of  luminous  spots  ;  Is,  spiracles.  About 
x  3 
at  night  into  lighted  apartments. 


-but   the   male    has  elytra   and 
ample  wings,  and  frequently  flies 


Although  so  little  has  been  ascertained  as  to  the  light  of  Lampy- 
ridae,  there  are  two  facts  that  justify  us  in  supposing  that  it  is  in 
some  way  of  importance  to  the  species.  These  are:  (1)  that  in  a  great 
many  species  the  eyes  have  a  magnificent  and  unusual  develop- 
ment ;  (2)  that  the  habits  of  the  creatures  are  in  nearly  all  cases 
nocturnal.  It  is  true  that  the  little  Phosphaenus  liemipterus  is 
said  to  be  diurnal  in  habits,  but  it  is  altogether  an  exceptional 
form,  being  destitute  of  wings  in  both  sexes,  and  possessed  of 
only  very  feeble  light -giving  powers,  and  we  have,  moreover, 
very  little  real  knowledge  as  to  its  natural  history :  it  is  said 

1  Bull.  cnt.  Hal.  1886,  p.  406,  and  Ent.  Zeit.  Stettin,  xliii.  1887,  pp.  201-206. 
Kmrry  does  not  mention  the  name  of  the  species,  but  \ve  presume  it  to  be  the 
common  Italian  fire-fly,  Luciola  italica. 


250  COLEOPTERA  CHAP. 

that  the  female  is  of  the  utmost  rarity,  though  the  male  is  not 
uncommon. 

The  nature  of  the  luminosity  of  Lampyris  has  given  rise 
to  many  contradictory  statements ;  the  light  looks  somewhat 
like  that  given  off  by  phosphorus,  and  is  frequently  spoken  of 
as  phosphorescence ;  but  luminescence  is  a  better  term.  The 
egg,  larva,  pupa,  and  male  are  luminous  as  well  as  the  female 
(at  any  rate  in  L.  noctilma^) ;  the  luminescence  is,  however,  most 
marked  in  the  female  imago,  in  which  it  is  concentrated  near 
the  extremity  of  the  abdomen ;  here  there  are  t\vo  strata  of 
cells,  and  many  fine  capillary  tracheae  are  scattered  through  the 
luminous  substance.  Wielowiejski  concludes  that  the  light- 
producing  power  is  inherent  in  the  cells  of  the  luminous  organ, 
and  is  produced  by  the  slow  oxidation  of  a  substance  formed 
under  the  influence  of  the  nervous  system.  The  cells  are 
considered  to  be  essentially  similar  to  those  of  the  fat-body.1 
The  luminescence  of  Lampyridae  is  very  intermittent,  that  is  to 
say,  it  is  subject  to  rapid  diminutions  and  increases  of  its 
brilliancy  ;  various  reasons  have  been  assigned  for  this,  but  all 
are  guesses,  and  all  that  can  be  said  is  that  the  changes  are 
possibly  due  to  diminution  or  increase  of  the  air-supply  in  the 
luminous  organ,  but  of  the  way  in  which  this  is  controlled  there 
seems  to  be  no  evidence.  Considerable  difference  of  opinion  has 
existed  as  to  the  luminescence  of  the  eggs  of  Lampi/ris.  If  it  exist 
in  the  matter  contained  in  the  egg,  it  is  evident  that  it  is 
independent  of  the  existence  of  tracheae  or  of  a  nervous  system. 
Newport  and  others  believed  that  the  light  given  by  the  egg 
depended  merely  on  matter  on  its  exterior.  The  observations  of 
Dubois  '2  show,  however,  that  it  exists  in  the  matter  in  the  egg ; 
he  has  even  found  it  in  the  interior  of  eggs  that  had  been 
deposited  unfertilised. 

From  time  to  time,  since  the  commencement  of  the  nineteenth 
century,  there  have  appeared  imperfect  accounts  of  extraordinary 
light-giving  larvae  found  in  South  America,  of  various  sizes,  but 
attaining  in  some  cases  a  length,  it  is  said,  of  three  inches ;  they 
are  reported  as  giving  a  strong  red  light  from  the  two  extremities 
of  the  body,  and  a  green  light  from  numerous  points  along  the 

1  Zcitschr.    iviss.    Zool.   xxxvii.    1882,    p.   354  ;   also  Emery,   op.   cit.    xl.    1S84, 
p.  338.     For  another  theory  as  to  the  luminescence,  see  p.  259. 

2  Bull.  Soc.  Zool.  France,  xii.  1887,  p.  137,  postea. 


v  POLYMORPHA — GLOW-WORMS  251 

sides  of  the  body,  and  hence  are  called,  it  is  said,  in  Paraguay 
the  railway-beetle.  We  may  refer  the  reader  to  Haase's  paper1 
on  the  subject  of  these  "  larvae,"  as  we  can  here  only  say  that  it 
appears  probable  that  most  of  these  creatures  may  prove  to  be 
adult  females  of  the  extraordinary  group  Phengodini,  in  which  it 
would  appear  that  the  imago  of  the  female  sex  is  in  a  more  larva- 
like  state  than  it  is  in  any  other  Insects.  The  males,  however, 
are  well-developed  beetles ;  unlike  the  males  of  Lampyrides,  in 
general  they  have  not  peculiar  eyes,  but  on  the  other  hand  they 
possess  antennae  which  are  amongst  the  most  highly  developed 
known,  the  joints  being  furnished  on  each  side  with  a  long 
appendage  densely  covered  with  pubescence  of  a  remarkable 
character.  There  is  no  reason  to  doubt  that  Haase  was  correct 
in  treating  the  Insect  we  figure  (Fig.  129,  B)  as  a  perfect  Insect ; 
he  is,  indeed,  corroborated  by  Eiley.2  The  distinctions  between  the 
larva  and  female  imago  are  that  the  latter  has  two  claws  on  the 
feet  instead  of  one,  a  greater  number  of  joints  in  the  antennae, 
and  less  imperfect  eyes  ;  the  female  is  in  fact  a  larva,  making  a 
slightly  greater  change  at  the  last  ecdysis,  than  at  those  previous. 
It  is  much  to  be  regretted  that  we  have  so  very  small  a  know- 
ledge of  these  most  interesting  Insects.  Malacodermidae  are 

O  O 

probably  the  most  imperfect  or  primitive  of  all  beetles,  and  it 
is  a  point  of  some  interest  to  find  that  in  one  of  them  the 
phenomena  of  metamorphosis  are  reduced  in  one  sex  to  a 
minimum,  while  in  the  other  they  are — presumably  at  least 
—normal  in  character. 

Numerous  larvae  of  most  extraordinary,  though  diverse, 
shapes,  bearing  long  processes  at  the  sides  of  the  body,  and 
having  a  head  capable  of  complete  withdrawal  into  a  slender 
cavity  of  the  thorax,  have  long  been  known  in  several  parts  of 
the  world,  and  Dr.  AVilley  recently  found  in  Xew  Britain  a 
species  having  these  body-processes  articulated.  Though  they 
are  doubtless  larvae  of  Lampyrides,  none  of  them  have  ever  been 
reared  or  exactly  identified. 

A  very  remarkable  Ceylouese  Insect,  Dioptoma  adamsi 
Pascoe,  is  placed  in  Lampyrides,  but  can  scarcely  belong  there,  as 
apparently  it  has  but  five  or  six  visible  ventral  segments ;  this 
Insect  has  two  pairs  of  eyes,  a  large  pair,  with  coarse  facets  on 

1  Deutsche  ent.  Zeitsclir.  xxxii.  1888,  pp.  145-167. 
-  Ent.  Mag.  xxiv.  1887,  p.  148. 


252 


COLEOPTERA 


CHAP. 


the  under  side  of  the  head,  and  a  moderate-sized  pair  with  fine 
facets  on  the  upper  side.  Nothing  is  known  as  to  the  habits  of 
this  curiosity,  not  even  whether  it  is  luminous  in  one  or  both  sexes. 
It  is  believed  that  the  perfect  instar  of  Lampyrides  takes  no 
food  at  all.  The  larvae  were  formerly  supposed  to  be  vegetarian, 
but  it  appears  probable  that  nearly  all  are  carnivorous,  the  chief 
food  being  Mollusca  either  living  or  dead.  The  larvae  are  active, 
and  in  many  species  look  almost  as  much  like  perfect  Insects  as 
do  the  imagos. 

The  other  divisions  of  Malacodermidae — Lycides,  Drilides, 
Telephorides — also  have  predaceous,  carnivorous  larvae.  All  these 
groups  are  extensive.  Though  much  neglected  by  collectors  and 
naturalists,  some  1500  species  of  the  family  Malacodermidae 
have  been  detected.  We  have  about  50  in  Britain,  and  many 
of  them  are  amongst  the  most  widely  distributed  and  abundant 
of  our  native  Insects.  Thus,  however  near  they  may  be  to  the 
primitive  condition  of  Coleoptera,  it  is  highly  probable  that  they 
will  continue  to  exist  alongside  of  the  primitive  Cockroaches  and 
Aptera,  long  after  the  more  highly  endowed  forms  of  Insect-life 
have  been  extinguished  wholesale  by  the  operations  of  mankind 
on  the  face  of  the  earth. 

Fam.  55.  Melyridae  (or  Malachiidae). — Six  visible  and  move- 
able  ventral  abdominal  segments;  the  basal  part  more  or  less  distinct  I;/ 

co-ailiijit,  <i  with  the  coxae.  These 
Insects  are  extremely  numerous, 
but  have  been  very  little  studied. 
In  many  works  they  are  classified 
with  Malacodermidae,  but  \vere 
correctly  separated  by  Leconte 
and  Horn,  and  this  view  is  also 
taken  by  Dr.  Yerhoelf,  the  latest 
investigator.  The  smaller  num- 
ber of  visible  ventral  segments 
appears  to  be  due  to  a  change 
at  the  base  correlative  with  an 
adaptation  between  the  base  of 
Britain,  the  abdomen  and  the  hind 
The  characters  are  singu- 
with  those  of 


FIG.    130. — Malacliius    aeneus. 

A,    Larva    (after    Ferris)  ;    B,    female 
imago. 


coxae. 

larly    parallel 
Silphidae ;  but  in  Melyridae  the  antennae  are  filiform  or  serrate, 


v  POLYMORPHA— MELYRIDAE CLERIDAE  253 

not  clavate.  The  habits  in  the  two  families  are  different,  as  the 
Melyridae  are  frequenters  of  flowers.  Many  of  the  Melyridae 
have  the  integument  soft,  but  in  the  forms  placed  at  the  end 
of  the  family — e.g.  Zyyia — they  are  much  firmer.  Thus  these 
Insects  establish  a  transition  from  the  Malacodermidae  to  ordi- 
nary Coleoptera.  Although  the  images  are  believed  to  consume 
some  products  of  the  flowers  they  frequent,  yet  very  little  is 
really  known,  and  it  is  not  improbable  that  they  are  to  some 
extent  carnivorous.  This  is  the  case  with  the  larvae  that  are  known 
(Fig.  130,  larva  of  Malachius  aeneus}.  These  are  said  by  Ferris 
to  bear  a  great  resemblance  to  those  of  the  genus  Telephorus, 
belonging  to  the  Malacodermidae. 

Fam.  56.  Cleridae. — Tarsi  five-jointed ;  but  the  basal  joint  of 
the  posterior  very  indistinct,  usually  very  small  above,  and  closely 
united  with  the  second  by  an  oblique  splice ;  the  apices  of  joints 
two  to  four  usually  prolonged  as  membranous  flaps  ;  anterior  coxae 
prominent,  usually  contiguous,  rather  large,  but  their  cavities  not 
prolonged  externally  ;  labial  palpi  usually  with  large  hatchet- 
shaped  terminal  joint ;  ventral  segments  fire  or  six,  very  mobile. 
The  Cleridae  are  very  varied  in  form  and  colours  ;  the  antennae 
are  usually  more  or  less  clubbed  at  the  tip,  and  not  at  all  serrate, 
but  in  Cylidrus  and  a  few  others  they  are  not  clubbed,  and  in 
Cylidrus  have  seven  flattened  joints.  The  student  should  be 
very  cautious  in  deciding  as  to  the  number  of  joints  in  the  feet 
in  this  family,  as  the  small  basal  joint  is  often  scarcely  dis- 
tinguishable, owing  to  the  obliteration  of  its  suture  with  the 
second  joint.  The  little  Alpine  Laricobius  has  the  anterior  coxal 
cavities  prolonged  externally,  and  the  coxae  receive  the  femora  to 
some  extent,  so  that  it  connects  Cleridae  and  Derodontidae.  The 
Cleridae  are  predaceous,  and  their  larvae  are  very  active ;  they 
are  specially  fond  of  wood-boring  Insects  ;  that  of  Tillvs  elon- 
gatus  (Fig.  131)  enters  the  burrows  of  Ptilinus  pectinicornis  in 
search  of  the  larva.  The  members  of  the  group  Corynetides 
frequent  animal  matter,  carcases,  bones,  etc.,  and,  it  is  said,  feed 
thereon,  but  Perris's  recent  investigations  *  make  it  probable  that 
the  larvae  really  eat  the  innumerable  Dipterous  larvae  found  in 
such  refuse ;  it  is  also  said  that  the  larvae  of  Cleridae  spin 
cocoons  for  their  metamorphosis ;  but  Ferris  has  also  shown 
that  the  larvae  of  Nccrobia  ruficollis  really  use  the  puparia  formed 

1  Larvcs  des  CoUopteres,  1878,  p.  208. 


254 


COLEOPTERA 


CHAP. 


by  Diptera.  Some  of  the  species  of  Necrobia  have  been  spread 
by  commercial  intercourse,  and  N.  rufipes  appears  to  be  now  one 
of  the  most  cosmopolitan  of  Insects.  The  beautifully  coloured 
Corynctcs  cor  rule  us  is  often  found  in  our  houses,  and  is  useful,  as 
it  destroys  the  death-watches  (Anolium}  that  are  sometimes  very 
injurious.  T'i'icho<les  apiarius,  a  very  lively  -coloured  red  and 
blue  beetle,  destroys  the  larvae  of  the  honey-bee,  and  Lampert 

has  reared  TricJiodes  a/reariits 
from  the  nests  of  Chalicodoma 
tiiuraria,  a  mason-bee;  he  re- 
cords that  one  of  its  larvae, 
after  being  full  grown,  remained 
twenty  -  two  months  quiescent 
and  then  transformed  to  a  pupa. 
Still  more  remarkable  is  a  case 
of  fasting  of  the  larva  of  Tri- 
cJiodes ammios  recorded  by 
Mayet:1  this  Insect,  in  its 

•> 


* 

ew  Forest). 


w«  ;'Tf'5' 

A,  Head  ;  B,  front  leg  ; 


C,  termination  of  the  body,  more  mag-    immature     form,    destrOVS     Ad'l- 

•  ft        -t  ** 


•  ft        -t 

dium  maroccanum  ;  a  larva  sent 

from  Algeria  to  M.  Mayet  refused  such  food  as  was  offered  to 
it  for  a  period  of  two  and  a  half  years,  and  then  accepted 
mutton  and  beef  as  food  ;  after  being  fed  for  about  a  year  and  a 
half  thereon,  it  died.  Some  Cleridae  bear  a  great  resemblance 
to  Insects  of  other  families,  and  it  appears  probable  that  they 
resemble  in  one  or  more  points  the  Insects  on  which  they  feed. 
The  species  are  now  very  numerous,  about  1000  being  known, 
but  they  are  rare  in  collections;  in  Britain  we  have  only  nine 
species,  and  some  of  them  are  now  scarcely  ever  met  with. 

Fam.  57.   Lymexylonidae.  —  Elongate  1)eef/>-*,  v/7/6  soft  integu- 


ments,  front  and  middle  coxae  exserted,  longitudinal  in 
hirxi  slender,  Jive-jointed  ;  (t/ife/m/tr  *//«/•/,  serrate,  Imt  I'nfli,  r  Iroad. 
Although  there  are  only  twenty  or  thirty  species  of  this  family, 
they  occur  in  most  parts  of  the  world,  and  are  remarkable  on 
account  of  their  habit  of  drilling  cylindrical  holes  in  hard  wood, 
after  the  manner  of  Anobiidae.  The  larva  of  Lymex'ijlon  navale  was 
formerly  very  injurious  to  timber  used  for  constructing  ships,  but 
of  late  years  its  ravages  appear  to  have  been  of  little  importance. 
The  genus  Atractocerus  consists  of  a  few  species  of  very  abnormal 

1  Ann.  Sue.  cut.  France,  1894,  p.  7. 


POLYMORPHA DASCILLIDAE 


255 


Coleoptera,  the  body  being  elongate  and  vermiform,  the  elytra 
reduced  to  small,  functionless  appendages,  while  the  wings  are 
ample,  not  folded,  but  traversed  by  strong  longitudinal  nervures, 
and  with  only  one  or  two  transverse  nervures.  Owing  to  the 
destruction  of  our  forests  the  two  British  Lymexylonidae — L. 
navale  and  Hylecoetus  dermestoides — are  now  very  rarely  met 
with. 

Fam.  58.  Dascillidae.- — Small  or  moderate-sized  beetles,  with 
I'dtlier  flimsy  integuments,  antennae  either  serrate,  filiform,  or 
even  made  flabellate  by  long  appen- 
dages ;  front  coxae  elongate,  greatly 
('.'•sc/'ted  ;  abdomen  ivith  jive  mobile 
1-i'ntral  segments  ;  tarsi  Jive-jointed. 
This  is  one  of  the  most  neglected 
and  least  known  of  all  the  families 
of  Coleoptera,  and  one  of  the  most 
difficult  to  classify  ;  though  always 
placed  amongst  the  Serricornia,  it 
is  more  nearly  allied  to  Paruidae 
and  Byrrhidae,  that  are  placed  in 

Clavicornia,  than  it  is  to  any  of  the  FlG_  132.  __  Hydrocyphou  deflexions. 
ordinary  families  of  Serricornia.  It 
is  probable  that  careful  study  will 
show  that  it  is  not  natural  as  at  present  constituted,  and  that  the 
old  families,  Dascillidae  and  Cyphonidae,  now  comprised  in  it,  will 
have  to  be  separated.  Only  about  400  species  are  at  present 
known;  but  as  nearly  100  of  these  have  been  detected  in  New 
Zealand,  and  17  in  Britain,  doubtless  the  numbers  in  other 
parts  of  the  world  will  prove  very  considerable,  these  Insects 
having  been  neglected  on  account  of  their  unattractive  exterior, 
;ind  fragile  structure.  The  few  larvae  known  are  of  three  or 
four  kinds.  That  of  Dascillus  cervinus  is  subterranean,  and  is 
believed  to  live  on  roots ;  in  form  it  is  somewhat  like  a  Lamelli- 
corn  larva,  but  is  straight,  and  has  a  large  head.  Those  of  the 
<  'yphonides  are  aquatic,  and  are  remarkable  for  possessing  antennae 
consisting  of  a  great  many  joints  (Fig.  132,  A).  Tournier 
describes  the  larva  of  Helodes  as  possessing  abdominal  but  not 
thoracic  spiracles,  and  as  breathing  by  coming  to  the  surface  of 
the  water  and  carrying  down  a  bubble  of  air  adhering  to  the 
posterior  part  of  the  body;  the  larva  of  Hydrocyplion  (Fig.  132,  A) 


Britain.     A,  Larva  (after  Tournier)  ; 
B,  imago. 


256 


COLEOPTERA 


CHAP. 


possesses  several  finger-like  pouches  that  can  be  exstulpated  at 
the  end  of  the  body.  It  is  probable  that  these  larvae  are  carni- 
vorous. The  imago  of  this  Insect  abounds  on  the  bushes  along 
the  banks  of  some  of  the  rapid  waters  of  Scotland ;  according  to 
Touriiier,  when  alarmed,  it  enters  the  water  and  goes  beneath  it 
for  shelter.  The  third  form  of  larva  belongs  to  the  genus  Euci- 
netus,  it  lives  on  fungoid  matter  on  wood,  and  has  ordinary 
antennae  of  only  four  joints.1  It  is  very  doubtful  whether 
Eucinetas  is  related  to  other  Dascyllidae  ;  some  authorities  indeed 
place  it  in  Silphidae. 

Fam.    59.    Rhipiceridae.--^?^  fire -jointed,  furnished  u-ith 
a   robust  onychium  (a  straight  chitinons  process   bearing  hairs) 

between  th  e  claws ;  a  ntennae  of 
the  male  bearing  long  processes, 
and  sometimes  consisting  of  a 
large  manlier  of  joints.  3fan- 
dibles  robust,  strongly  curved, 
and  almost  calliper -like  in 
form.  This  small  family  of 
less  than  100  species  is  widely 
distributed,  though  confined  to 
the  warmer  regions  of  the 
earth,  a  single  species  occur- 
ring in  the  extreme  south  of 
Eastern  Europe.  Very  little 
is  known  as  to  the  natural 
history.  The  larva  of  Calli- 
rhipis  dcjcani  (Fig.  133,  A)  is 
described  by  Schiodte  as  hard, 
cylindrical  in  form,  and  peculi- 
truncate  behind,  so  that 


FIG.   133. — A,  Larva  of  GaUirhqris  dejeani 

(after  Schiiidte)  ;  B,  Rliipicrra  mystacina    there  appear    to    be    Ollly    eight 
male,  Australia ;   C,  under  side  of  its  hind      •,    •,         •       i  • 

foot.  abdominal  segments,  trie  ninth 

segment  being  so   short   as   to 

look  like  an  operculum  at  the  extremity  of  the   body.      It   lives 
in  wood. 

Fam.  60.  Elateridae  (Click-beetles]. — Antennae  more  or  less 
serrate  along  the  inner  margin,  frequently  pei'fi /i«/<\  rarely 
filiform.  Front  coxae  small,  spherical.  Thorax  -usually  with 

1  Perris,  Ann.  >SW.  ent.  France  (2)  ix.  1851,  p.  48. 


CLICK-BEETLES 


257 


FIG.  13-1. — Athous  rhombeus.  New 
Forest.  A,  Larva  ;  B,  female 
imago. 


J/ i /if?  nn  riles  more  or  less  prolonged  backwards;  with  a  prosternal 
process  that  can  he  received  in,  and  usually  can  move  in,  a 
mesosternal  cavity.  Hind  coxa  with  a  plate,  above  which  the  femur 
can  lie  received.  Visible  ventral  segments  'usually  Jive,  only  the 
if  i- initial  one  being  mobile.  Tarsi  Jive-jointed.  This  large  family 
of  Coleoptera  comprises  about  7000 
species.  Most  of  them  are  readily 
known  by  their  peculiar  shape,  and 
by  their  faculty  of  resting  on  the 
back,  stretching  themselves  out 
flat,  and  then  suddenly  o-oing  off 

t/  O  O 

with  a  click,  and  thus  jerking 
themselves  into  the  air.  Some, 
however,  do  not  possess  this  faculty, 
and  certain  of  these  are  extremely 
difficult  to  recognise  from  a  defi- 
nition of  the  family.  According 
to  Bertkau1  our  British  Lacon 
murinus  is  provided  near  the 
tip  of  the  upper  side  of  the  ab- 
domen with  a  pair  of  eversible 

glands,  comparable  with  those  that  are  better  known  in  Lepi- 
dopterous  larvae.  He  states  that  this  Insect  does  not  try 
to  escape  by  leaping,  but  shams  death  and  "  stinks  away '  its 
enemy.  The  glands,  it  would  appear,  become  exhausted  after  the 
operation  has  been  repeated  many  times.  The  extent  of  the  leap 
executed  by  click -beetles  differs  greatly ;  in  some  species  it  is 
very  slight,  and  only  just  sufficient  to  turn  the  Insect  right  side 
up  when  it  has  been  placed  on  its  back.  In  some  cases  the 
Insects  go  through  the  clicking  movements  with  little  or  no 
appreciable  result  in  the  way  of  consequent  propulsion.  Although 
it  is  difficult  to  look  on  this  clicking  power  as  of  very  great  value 
to  the  Elateridae,  yet  their  organisation  is  profoundly  modified  so 
us  to  permit  its  accomplishment.  The  junction  of  the  prothorax 
with  the  after-body  involves  a  large  number  of  pieces  which  an- 
all  more  or  less  changed,  so  that  the  joint  is  endowed  with  greater 
mobility  than  usual;  while  in  the  position  of  repose,  on  the  other 
hand,  the  two  parts  are  firmly  locked  together.'  The  thoracic 
stigma  is  of  a  highly  remarkable  nature,  and  the  extensive 

1  Arch.  Naturgesch.  xlviii.  1,  1882,  p.  371. 
VOL.  VI  S 


258  COLEOPTERA 


CHAP. 


membrane  in  which  it  is  placed  appears  to  be  elastic.  Although 
the  mechanics  of  the  act  of  leaping  are  still  obscure,  yet  certain 
points  are  clear ;  the  prosternal  process  possesses  a  projection,  or 
notch,  on  its  upper  surface  near  the  tip  ;  as  a  preliminary  to 
leaping,  this  projection  catches  against  the  edge  of  the  meso- 
sterual  cavity,  and  as  long  as  this  position  is  maintained  the 
Insect  is  quiescent ;  suddenly,  however,  the  projection  slips  over 
the  catch,  and  the  prosternal  process  is  driven  with  force  and 
rapidity  into  the  mesosternal  cavity  pressing  against  the  front 
wall  thereof,  and  so  giving  rise  to  the  leap. 

Several  larvae  are  well  known  ;  indeed  the  "  wire-worms " 
that  are  sometimes  so  abundant  in  cultivated  places  are  larvae 
of  Elateridae.  In  this  instar  the  form  is  usually  elongate  and 
nearly  cylindrical ;  the  thoracic  segments  differ  but  little  from 
the  others  except  that  they  bear  rather  short  legs ;  the  skin 
is  rather  hard,  and  usually  bears  punctuation  or  sculpture ; 
the  body  frequently  terminates  in  a  very  hard  process,  of 
irregular  shape  and  bearing  peculiar  sculpture  on  its  upper 
surface,  while  beneath  it  the  prominent  anal  orifice  is  placed  :  this 
is  sometimes  furnished  with  hooks,  the  function  of  which  has 
not  yet  been  observed.  The  majority  of  these  larvae  live  in 
decaying  wood,  but  some  are  found  in  the  earth  ;  as  a  rule  the 
growth  is  extremely  slow,  and  the  life  of  the  larva  may  extend 
over  two  or  more  years.  Some  obscurity  has  prevailed  as  to  their 
food  ;  it  is  now  considered  to  be  chiefly  flesh,  though  some  species 
probably  attack  decaying  roots ;  and  it  is  understood  that  wire- 
worms  destroy  the  living  roots,  or  underground  stems,  of  the  crops 
they  damage.  Various  kinds  of  Myriapods  (see  Vol.  Y.  p.  29)  are 
often  called  "wire-worm,"  but  they  may  be  recognised  by  possessing 
more  than  six  legs.  The  larvae  of  the  genus  Cardiophorus  are  very 
different,  being  remarkably  elongate  without  the  peculiar  terminal 
structure,  but  apparently  composed  of  twenty-three  segments. 

The  genus  Pyrophorus  includes  some  of  the  most  remarkable 
of  light-giving  Insects.  There  are  upwards  of  100  species, 
exhibiting  much  diversity  as  to  the  luminous  organs ;  some 
are  not  luminous  at  all ;  but  all  are  peculiar  to  the  Xew  "\Vorld, 
with  the  exception  that  there  may  possibly  be  luminous  species, 
allied  to  the  American  forms,  in  the  Fiji  Islands  and  the  New 
Hebrides.  In  the  tropics  of  America  the  Pyrophorits,  or  Cucujos, 
form  one  of  the  most  remarkable  of  the  natural  phenomena. 


v  ELATERIDAE FIRE-FLIES  259 

The  earliest  European  travellers  in  the  New  World  were  so  im- 
pressed by  these  Insects  that  descriptions  of  their  wondrous  display 
occupy  a  prominent  position  in  the  accounts  of  writers  like  Oviedo, 
whose  works  are  nearly  400  years  old.  Only  one  of  the  species 
has,  however,  been  investigated.  P.  noctiliicus  is  one  of  the  most 
abundant  and  largest  of  the  Pyroplnirux,  and  possesses  011  each  side 
of  the  thorax  a  round  polished  space  from  which  light  is  given 
forth  ;  these  are  the  organs  called  eyes  by  the  older  writers. 
Besides  these  two  eye-like  lamps  the  Insect  possesses  a  third 
source  of  light  situate  at  the  base  of  the  ventral  surface  of  the 
abdomen  ;  there  is  no  trace  of  this  latter  lamp  when  the  Insect 
is  in  repose  ;  but  when  on  the  wing  the  abdomen  is  bent  away  from 
the  breast,  and  then  this  source  of  light  is  exposed ;  hence,  when 
Hying,  this  central  luminous  body  can  be  alternately  displayed 
and  concealed  by  means  of  slight  movements  of  the  abdomen. 
The  young  larva  of  P.  noctilucus  is  luminous,  having  a  light- 
giving  centre  at  the  junction  of  the  head  and  thorax  ;  the  older 
larva  has  also  numerous  luminous  points  along  the  sides  of  the 
body  near  the  spiracles.  It  is  remarkable  that  there  should 
be  three  successive  seats  of  luminescence  in  the  life  of  the  same 
individual.  The  eggs  too  are  said  to  be  luminous.  The  light 
given  off  by  these  Insects  is  'extremely  pleasing,  and  is  used  by 
the  natives  on  nocturnal  excursions,  and  by  the  women  for  orna- 
ment. The  structure  of  the  light-organs  is  essentially  similar 
to  that  of  the  Lampyridae.  The  light  is  said  to  be  the  most 
economical  known  ;  all  the  energy  that  is  used  being  converted 
into  light,  without  any  waste  by  the  formation  of  heat  or 
chemical  rays.  The  subject  has  been  investigated  by  Dubois,1  who 
comes,  however,  to  conclusions  as  to  the  physiology  of  the 
luminous  processes  different  from  those  that  have  been  reached 
by  Wielowiejski  and  others  in  their  investigations  011  Glow- 
worms. He  considers  that  the  light  is  produced  by  the  reactions 
of  two  special  substances,  luciferase  and  luciferine.  Lucifernse 
is  of  the  nature  of  an  enzyme,  and  exists  only  in  the  luminous 
organs,  in  the  form,  it  is  supposed,  of  extremely  minute  granules. 
Luciferine  exists  in  the  blood  ;  and  the  light  is  actually  evoked 
by  the  entry  of  blood  into  the  luminous  organ. 

We  have  given  to  this  family  the  extension  assigned  to  it  by 

1   "  Les  Elateridea  hnniueux,"  Bull.  Soc.   Zool.   France,   xi.  1SS6  ;  also  Lemons 
dc  I'/ii/xin/tii/i'i'  iji'ngralc,  Paris.  1898,  and  C.R.  Ac.  Sci.  cxxiii.  1S96,  p.  653. 


260 


COLEOPTERA 


CHAP. 


Schiodte.  Leconte  and  Horn  also  adopt  this  view,  except  that 
they  treat  Throscides  as  a  distinct  family.  By  most  authors 
Eucnemides,  Throscides,  and  Cebrionides  are  all  considered  dis- 
tinct families,  but  at  present  it  is  almost  impossible  to  separate 
them  on  satisfactory  lines.  The  following  table  from  Leconte 
and  Horn  exhibits  the  characters  of  the  divisions  so  far  as  the 
imago  is  concerned  :— 

Posterior  coxae  laminate  ;  trochanters  small. 

Labrum    concealed  ;    antennae   somewhat    distant    from    the    eyes,    their 


insertion  narrowing  the  front 


EUCXEMIDES. 


Labnuu  visible,  free;   antennae  arising   near  the  eyes  under   the   frontal 
margin         .....  ELATERIDES. 

Lalirum  transverse,  connate  with  the  front. 

Ventral  segments  six  ;  claws  simple  ;  tibial  spurs  well  developed. 

(  'EBRIOXIDES. 
Ventral  segments  five  ;  claws  serrate  ;  tibial  spurs  moderate. 

PEROTHOPIDES. 

Posterior  coxae  not  laminate  ;   trochanters  of  middle  and  posterior  legs  very 
long   .  .  ...      CEROPHYTIDES. 

Throscides    are     considered     to     be     distinguished     by     the 

mesosternum  being  impressed  on  each  side 
in  front  for  the  accommodation  of  the 
posterior  face  of  the  front  coxae.  The 
genus  Throscus  has  the  antennae  clavate. 
The  classification  of  the  Elaterides  and 
these  forms  is  a  matter  of  the  greatest 
difficulty,  and,  if  the  larvae  are  also 
considered,  becomes  even  more  complex. 
Cebrionid  larvae  are  different  from 
those  of  any  of  the  other  divisions,  and 
possess  laminate,  not  calliper-like,  man- 
dibles. The  larvae  of  Eucnemides  (Fig. 
135)  are  very  little  known,  1  >ut  are 
highly  remarkable,  inasmuch  as  it  is 

FIG.     135. -Larva    of    Forna.c  difficult  to  lilld  any    mouth-opeiling 

n.  sp.     Hawaii.     A,   Upper 

side;  B,  under  side:  s  *,  in  some  of  them,  and  they  have  no  legs. 
Ei^ore  Srjd  \  g  The  other  divisions  possess  very  few  species 
under  side  of  terminal  seg-  compared  with  Elaterides.  Iii  Britain 

ment  ;  a.  anus.  i  •>  •  •  p    T-II 

we  have  about  sixty  species  ot  Elate- 
rides, four  of  Throscides  and  three  of  Eucnemides ;  Cerophytum 
was  probably  a  native  many  years  ago.  Neither  Perothopides 


POLYMORPHA BUPRESTIDAE 


26l 


nor  Cebrionides  are  represented  in  our  fauna  ;  the  former  of  these 
two  groups  consists  only  of  four  or  five  North  American  species, 
and  the  Cerophytides  are  scarcely  more  numerous. 

Fam.  61.  Buprestidae. — Antennae  serrate,  never  elongate  ; 
prothorax  fitting  closely  to  the  after-body,  with  a  process  received 
into  a  cavity  of  the  mesosternum  so  as  to  permit  of  no  movements 
of  nutation.  Five  visible  ventral  segments,  the  first  usually 
elongate,  closely  'united  with,  t/ic  second,  the  others  mobile.  Tarsi 
five-jointed,  the  first  four  joints  usually  with  membranous  pads 
beneath.  This  family  is  also  of  large  extent,  about  5000  species 
being  known.  Many  of  them  are  remarkable  for  the  magnificence 
of  their  colour,  which  is  usually  metallic,  and  often  of  the  greatest 
brilliancy  ;  hence  their  wing-cases  are 
used  by  our  own  species  for  adorn- 
ment. The  elytra  of  the  eastern  kinds 
of  the  genus  Sternocera  are  of  a  very 
brilliant  green  colour,  and  are  used 
extensively  as  embroidery  for  the 
dresses  of  ladies  ;  the  bronze  elytra 
of  Buprestis  (Euchroma)  gigantea 
were  used  by  the  native  chieftains  in 
South  America  as  leg -ornaments,  a 
large  number  being  strung  so  as  to 
form  a  circlet.  The  integument  of 
the  Buprestidae  is  very  thick  and  hard, 
so  as  to  increase  the  resemblance  to 
metal.  The  dorsal  plates  of  the  abdo- 
men are  usually  soft  and  colourless  in 
beetles,  but  in  Buprestidae  they  are 
often  extremely  brilliant.  The  metallic  colour  in  these  Insects  is 
not  due  to  pigment,  but  to  the  nature  of  the  surface.  Buprestidae 
appear  to  enjoy  the  hottest  sunshine,  and  are  found  only  where  there 
is  much  summer  heat.  Australia  and  Madagascar  are  very  rich 
in  species  and  in  remarkable  forms  of  the  family,  while  in  Britain 
we  possess  only  ten  species,  all  of  which  are  of  small  size,  and 
nearly  all  are  excessively  rare.  The  family  is  remarkably  rich  in 
fossil  forms;  no  less  than  28  percent  of  the  Mesozoic  beetles 
found  by  Heer  in  Switzerland  are  referred  to  Buprestidae. 

The  larvae  (Fig.  136,  A)  find  nourishment  in  living  vegetable 
matter,  the  rule  being   that  they  form  galleries  in  or  under  the 


FIG.  136. — A,  Larva  of  Euchroma 
(joliath  (after  Schiodte) ;  B,  imago 
of  MdanopMla  decostiyma. 
Europe. 


262  COLEOPTERA 


CHAP. 


bark  of  trees  and  bushes,  or  in  roots  thereof;  some  inhabit  the 
stems  of  herbaceous  plants  and  one  or  two  of  the  smaller  forms  have 
been  discovered  to  live  in  the  parenchyma  of  leaves.  A  few  are  said 
to  inhabit  dead  wood,  and  in  Australia  species  of  Etlion  dwell  in 
galls  on  various  plants.  Buprestid  larvae  axe  of  very  remarkable 
shape,  the  small  head  being  almost  entirely  withdrawn  into  the 
very  broad  thorax,  while  the  abdomen  is  slender.1  A  few,  how- 
ever, depart  from  this  shape,  and  have  the  thoracic  region  but 
little  or  not  at  all  broader  than  the  other  parts.  The  larvae  of 
Julodis — a  genus  that  inhabits  desert  or  arid  regions — are 
covered  with  hair ;  they  have  a  great  development  of  the 
mandibles  ;  it  is  believed  that  they  are  of  subterranean  habits, 
and  that  the  mandibles  are  used  for  burrowing  in  the  earth. 
Only  the  newly  hatched  larva  is,  however,  known. 


Series  IV.  Heteromera. 

Tarsi  of  the  front  and  middle  legs  with  five,  tJiOse  of  the  hind 

legs  with  four,  joints. 

This  series  consists  of  some  14,000  or  15,000  species. 
Twelve  or  more  families  are  recognised  in  it,  but  the  majority  of 
the  species  are  placed  in  the  one  great  family,  Tenebrionidae. 
The  number  of  visible  ventral  segments  is  nearly  always  live. 
Several  of  the  families  of  the  series  are  of  doubtful  validity  ; 
indeed  beyond  that  of  Tenebrioiiidae  the  taxonomy  of  this  series 
is  scarcely  more  than  a  convention.  The  larvae  may  be  con- 
sidered as  belonging  to  three  classes  :  one  in  which  the  body  is 

o       o  */ 

cylindrical  and  smooth  and  the  integument  harder  than  usual  in 
larvae ;  a  second  in  which  it  is  softer,  and  frequently  possesses 
more  or  less  distinct  pseudopods,  in  addition  to  the  six  thoracic 
legs;  and  a  third  group  in  which  hypermetamorphosis  prevails, 
the  young  larvae  being  the  creatures  long  known  as  Triungulins, 
and  living  temporarily  on  the  bodies  of  other  Insects,  so  that 
they  were  formerly  supposed  to  be  parasites. 

1  It  seems  impossible  to  understand  the  morphology  of  the  anterior  segments  by 
mere  inspection  ;  the  anterior  spiracle  being  seated  on  the  segment  behind  the 
broad  thorax.  Considerable  difference  of  opinion  has  prevailed  as  to  what  is  head, 
what  thorax  ;  the  aid  of  embryology  is  necessary  to  settle  the  point.  The  larva 
described  by  AVestwood  (Mod.  Classif.  i.  1839,  p.  229),  and  figured  as  probably 
Buprestis  atttximf".  is  doubtless  a  Passalid. 


V 


HETEROMERA 


263 


3 

1 


h-h  mditor.  Europe,  etc.   A, 

Larva    (meal-worm);     B,     pupa     (after 

Schiodte)  ;  c,  imago. 


Fam.  62.  Tenebrionidae.  —  Front  coxae  short,  not  projecting 
from  the  cavities,  enclosed  InhimJ.  Feet  destitute  of  lobed  joints. 
Clmcs  smooth.  This  is  one  of  the  largest  families  of  Coleoptera, 
about  10,000  species  being  already  known.  A  very  large  portion 
of  the  Tenebrionidae  are  entirely  terrestrial,  wings  suitable  for  flight 
being  absent,  and  the  elytra  frequently  more  or  less  soldered.  Such 
forms  are  described  in  systematic  works  as  apterous.  Unfortunately 
no  comprehensive  study  has 
ever  been  made  of  the  wings 
or  their  rudiments  in  these 
"  apterous  forms."  It  is  prob- 
able that  the  wings,  or  their 
rudiments  or  vestiges,  always 
exist,  but  in  various  degrees  of 
development  according  to  the 
species,  and  that  they  are  never  A  y 
used  by  the  great  majority  of  the 
terrestrial  forms.  Man  v  of  the  Flc-  137-— 

,      „      ,.  m         .     .       .  .. 

wood  -  feeding     Tenebrionidae, 
and  the  genera  usually  placed 

at  the  end  of  the  family,  possess  wings  well  adapted  for  flight. 
The  apterous  forms  are  chiefly  ground  -beetles,  living  in  dry 
places  ;  they  are  very  numerous  in  Africa,  California,  and 
North  Mexico.  Their  colour  is  nearly  always  black,  and  this  is 
probably  of  some  physiological  importance  ;  the  integuments  are 
thick  and  hard,  and  if  the  wing-cases  are  taken  off,  it  will  be 
found  that  they  are  usually  more  or  less  yellow  on  the  inner  face, 
even  when  jet-black  externally  ;  the  external  skeleton  is  very  closely 
fitted  together,  the  parts  that  are  covered  consisting  of  very  delicate 
membrane  ;  the  transition  between  the  hard  and  the  membranous 
portions  of  the  external  skeleton  is  remarkably  abrupt.  These 
ground-Tenebrionidae  form  a  very  interesting  study,  though,  on 
account  of  their  unattractive  appearance,  they  have  not  received 
the  attention  they  deserve. 

Many    of    the     Tenebrionidae,    notwithstanding    their    dark 

1  Casey  has  examined  the  wings  in  the  genus  Blapstinus  (an  "apterous" 
genus),  and  found  that  the  wings  are  extremely  varied  in  development,  according 
to  the  species  ;  in  no  case,  however,  did  they  appear  to  be  capable  of  giving  more 
than  a  laboured  and  feeble  flight.  —  Ann.  Neio  York  Ac.  v.  1890,  p.  416. 

In  Eleodcs,  though  the  meso-  and  meta-notum  are  formed  of  delicate  membrane, 
the  wings  exist  as  minute  flaps,  requiring  some  examination  for  their  detection. 


264  COLEOPTERA  CHAP. 

colours,  are  diurnal  in  habits,  and  some  of  them  run 
with  extreme  velocity  in  places  so  bare  and  desert  that  the 
means  of  existence  of  the  Insects  is  a  mystery.  Most  of  the 
Tenebrionidae,  however,  shun  the  light.  The  food  is  usually 
vegetable  matter,  and  it  is  apparently  preferred  in  a  very  dry 
state.  Mr.  Gahan  has  recently  recorded  that  in  Praogena 
the  under  surface  of  the  head  has  the  gular  region  striate  for 
stridulating  purposes.  This  is  the  only  instance  known  of  a 
voice -organ  in  this  situation,  and  moreover  is  the  only  case 
in  all  the  Tenebrionidae  in  which  any  sound-producing  organ 
has  been  discovered.  The  larvae  exhibit  but  little  variety,  they 
are  elongate  and  cylindrical,  with  harder  integument  than  is  usual 
in  Coleopterous  larvae ;  they  have  six  thoracic  legs,  and  at  the 
under  side  of  the  posterior  extremity  the  anus  serves  as  a  very 
short  pseudopod.  The  resemblance  of  these  larvae  to  those  of 
Elateridae  is  considerable  :  but  though  the  body  is  terminated  by 
one  or  two  small  processes,  these  never  attain  the  complexity  of 
the  terminal  segment  of  Elateridae.  The  common  meal-worm— 
i.e.  the  larva  of  Tenebrio  molitor — is  a  very  characteristic  example 
of  the  group.  The  pupae  are  remarkable  on  account  of  peculiar 
projections,  of  varied  and  irregular  form,  that  exist  on  the  sides 
of  the  abdominal  segments.  Britain  is  very  poor  in  these  Insects  ; 
our  list  of  them  scarcely  attains  the  number  of  thirty  species. 

Fam.  63.  Cistelidae. — Claws  comb-like.  The  very  obscure 
beetles  forming  this  family  are  only  separated  from  Tenebrionidae 
on  account  of  their  pectinate  claws.  About  500  species  of  Cis- 
telidae are  recorded  ;  the  early  instars,  so  far  as  known,  do  not 
differ  from  those  of  Tenebrionidae ;  the  larvae  are  believed  to  live 
on  dead  wood. 

Fam.  64.  Lagriidae. — Anterior  coxal  cavities  dosed,  tips  of 
the  front  coxae  free,  claws  smooth,  penultimate  joint  of  the  tarti 
broader,  j>t>l>rxecnt  beneath.  This  family  has  very  little  to  dis- 
tinguish it  from  Tenebrionidae,  and  the  group  Heterotarsini 
appears  to  connect  the  two.  It  is  a  small  family  of  about  200 
species,  widely  distributed,  and  represented  in  Britain  by  one 
species,  Lai/fia  hirta.  The  early  instars  are  similar  to  those  of 
the  Tenebrionidae,  except  that  the  larva  is  less  retiring  in  its 
habits  and  wanders  about  on  foliage:  it  is  of  broader  form  than 
that  of  most  of  the  Tenebrionidae.  The  pupa  has  long  projections 
at  the  sides  of  the  abdominal  segments. 


HETEROMERA  265 


Fam.  65.  Othniidae. — Only  about  ten  species  are  known  of  this 
dubious  family.  They  are  small  Insects  with  weak  integument, 
and  are  said  by  Leconte  and  Horn  to  be  distinguished  from 
"  degraded  Tenebrionidae "  by  the  more  mobile  abdominal  seg- 
ments, the  hind-margins  of  which  are  semi -membranous.  The 
antennae  are  of  the  clubbed  shape,  characteristic  of  "  Clavicornia," 
but  this  also  occurs  in  numerous  undoubted  Tenebrionidae. 
Species  of  Otlinius  have  been  found  in  Japan  and  Borneo,  as 
well  as  in  North  America.  Nothing  is  known  as  to  their 
metamorphoses. 

Fam.  66.  ^Egialitidae. — All  the  coxae  very  ividely  separated ; 
mi  co-adaptation  Between  the  sides  of  the  abdomen  and  the  edges  of 
the  wing-cases ;  five  ventral  segments  and  tip  of  a  sixth  visible. 
Two  minute  and  rare  Insects  from  North-West  America  constitute 
this  family.  It  is  distinguished  from  Pythidae  by  the  minute 
front  coxae,  widely  separated,  completely  closed  in,  and  deeply 
embedded  in  the  prosternum. 

Fam.  67.  Monommidae.--This  is  a  small  family  of  less  than 
100  species,  the  members  of  which  have  the  details  of  their 
external  structure  much  modified,  permitting  the  Insect  to  pack 
itself  up  in  repose  in  a  very  perfect  manner.  *  They  are  of  small 
size  and  oval  form  ;  and  are  absent  from  Europe  and  the  Anti- 
podes. Nothing  appears  to  be  known  as  to  the  metamorphosis. 

Fam.  68.  Nilionidae. — Broad,  circular  Heteromera,  of  moderate 
size,  with  the  front  coxae  but  little  separated,  and  the  anterior 
acetabula  closed,  though  having  the  appearance  of  being  open  in 
consequence  of  the  tips  of  the  epimera  being  free.  The  infle,<-«/ 
portion  of  the  wing-cases  remarkably  broad.  A  small  family  of 
less  than  fifty  species,  found  on  fungi,  chiefly  in  South  America. 
The  metamorphoses  are  not  known.  It  is  of  very  doubtful 
validity. 

Fam.  69.  Melandryidae. — Head  not  constricted,  behind  the 
eyes ;  anterior  acetabula  not  closed ;  claws  smooth.  Prothorax  broad 
behind.  These  are  loosely -fitted- together  Insects,  of  moderate 
or  small  size,  frequenting  dry  wood  or  fungi.  About  200  species 
are  known,  found  chiefly  in  temperate  regions.  The  few  described 
larvae  are  rather  varied  in  their  details  and  cannot  be  generalised 
at  present.  The  characters  of  the  members  of  this  family  require 
fresh  investigation. 

Fam.  70.  Pythidae. — Distinguished  from  Melandryidae  by  the 


266  COLEOPTERA 


CHAP. 


prothorax  being  narrow  behind.  This  is  a  small  family  of  about 
100  species,  found  in  temperate  regions  in  connection  with 
timber.  The  species  of  Iihi/msum/s  have  the  head  prolonged  in 
front  of  the  antennae  so  as  to  form  a  beak.  The  larva  of  Pytho 
</,'ji,'i'xsi/s  is  flat  and  has  parallel  sides  ;  the  body  is  terminated  by 
two  widely-separated  sharp  processes.  It  is  found  occasionally 
under  the  bark  of  firs  in  Scotland. 

Fam.  71.  Pyrochroidae. — Differs  from  Melandryidae  by  the 
head  forming  a  very  narrow  neck  behind,  and  by  the  penultimate 
tarsal  joints  being  broad.  They  are  feeble  Insects,  though  active 
on  the  wing.  They  are  destitute  of  any  of  the  various  remark- 
able structures  found  in  Mordellidae.  Only  about  forty  species 
are  known,  and  the  family  is  confined  to  the  north  temperate 
region,  being  best  represented  in  Japan.  Pyrocliroa  rubens  is 
common  in  some  parts  of  England ;  the  larva  is  found  under 
the  bark  of  tree-stumps  ;  it  is  remarkably  flat,  and  has  the  eighth 
abdominal  segment  unusually  long,  while  the  ninth  terminates 
the  body  in  the  form  of  two  long  sharp  processes. 

Fam.  72.  Anthicidae. — Head  v:ith  an  abrupt  narrow  neck ; 
'jirafhorax  narrower  than  the  elytra.  Middle  and  hind  coxae  placed 
in  definite  aeetalnda.  Cla-ics  single.  These  little  Insects  are 
numerous  in  species  ;  they  have  little  resemblance  to  Pyrochroidae, 
though  the  characters  of  the  two  families  cause  us  to  place 
them  in  proximity.  There  are  about  1000  species  known; 
though  we  have  only  about  12  in  Britain,  they  are  very 
numerous  in  the  Mediterranean  region.  The  family  Pedilidae 
of  Lacordaire  and  some  others  is  now  merged  in  Anthicidae. 
Thomson  and  Champion,  on  the  other  hand,  separate  some  very 
minute  Insects  to  form  the  family  Xylophilidae,  on  account  of 
certain  differences  in  the  form  of  the  abdomen  and  tarsi.  The 
Xylophilidae  live  in  dead  wood  ;  the  Anthicidae,  on  the  surface  of 
the  earth,  after  the  manner  of  ground-beetles ;  very  little  is, 
however,  known  as  to  their  natural  history. 

Fam.  73.  Oedemeridae. — Prothorax  not  forming  sharp  edges 
at  the  sides,  head  qcifjint/f  a  narrow  neel:  Pen /////' t/n/fr  tarsal 
joint  broad ;  cla-n-s  smooth.  These  Insects  usually  have  a  feeble 
integument,  and  bear  a  certain  resemblance  to  Malacodermidae. 
Less  than  500  species  are  known,  but  they  are  widely  distri- 
buted, and  occur  in  both  temperate  and  tropical  regions.  The 
larvae  live  in  old  wood.  Nac<'/'d>x  melanura  is  common  on  our 


V 


HETEROMERA MORDELLIDAE 


267 


FIG.  138. — Asdera  cnernlea.  A,  Larva  ; 
B,  pupa  (after  Scbiudte)  ;  C,  imago. 
Cambridge. 


coasts,  where  its  larva  lives  in  timber  cast  up  by  the  sea,  or 
brought  down  by  Hoods,  and  it 
is  able  to  resist  immersion  by 
the  tide.  It  is  remarkable  from 
the  possession  of  five  pairs  of 
dorsal  false  feet  on  the  anterior 
segments,  and  two  pairs  on 
the  ventral  aspect.  In  Asdera 
caerv.lea  there  are  six  dorsal  and 
three  ventral  pairs  of  these  re- 
markable pseudopods.  "We  have 
six  species  of  Oedemeridae  in 
Britain,  including  Asdera  as 
well  as  Naccrilcs. 

Fam.  74.  Mordellidae  (incl. 
Rhipiphoridae). — Head  peculiarly  formed,  vertex  lobcd  or  ridged 
behind,  so  that  in  extension  it  looses  on  the  front  edge  of  the  pvo- 
notum ;  capable  of  great  inflection  and  then  covering  the  pro  sternum  ; 
hind  coxae  with  laminae  forming  a  sharp  edge  behind,  frequently 
very  large.  This  family  is  a  very  distinct  one,  though  it  exhibits 
great  variety.  Lacordaire  has  pointed  out  that  Rmpiphoridae 
cannot  at  present  be  satisfactorily  distinguished  from  Mordellidae. 
Leconte  and  Horn  separate  the  two  by  the  fact  that  the  sides 
of  the  prothorax  form  a  sharp  edge  in  Mordellidae,  but  not  in 
Khipiphoridae.  A  better  character  would  perhaps  be  found  by  a 
study  of  the  head,  but  as  this  would  clearly  result  in  a  radical 
change  in  the  composition  of  the  two  families  it  is  preferable  to 
treat  them  at  present  as  only  sub-families :  if  placed  on  a  similar 
basis  to  the  preceding  families,  the  group  would  however  form, 
not  two,  but  several  families.  Besides  the  unusual  shape  of  the 
head  (Fig.  130,  D)  the  ventral  region  of  the  body  is  remarkably 
formed,  being  very  convex,  and  in  many  Mordellides  terminating 
in  a  strong  spinous  process  (Fig.  139,  C).  The  elytra  are,  in 
several  Ehipiphorids,  of  the  groups  Myoditini  and  Rhipidiini, 
reduced  to  a  very  small  size,  and  the  wings  are  not  folded.  The 
Mordellidae  are  remarkable  for  their  activity;  in  the  perfect 
state  they  usually  frequent  flowers,  and  fly  and  run  with  extreme 
rapidity.  Mordellides  are  amongst  the  most  numerous  and 
abundant  of  the  European  Coleoptera,  and  in  Britain  the 
Anas-oini  swarm  on  the  flowers  of  bushes  and  Umbelliferae.  The 


268 


COLEOPTERA 


CHAP. 


life-histories  appear  to  be  singularly  varied :  hut  unfortunately 
they  are  incompletely  known.  The  larvae  of  some  of  the 
Mordellids  have  been  found  in  the  stems  of  plants,  and 
derive  their  nutriment  therefrom.  This  is  said  by  Schwarz 
to  be  undoubtedly  the  case  with  Moi'flcUistcna  floridensis. 
Coquillett  has  found  the  larvae  of  J/  i>nx1iil«l«.  in  plant-stems 
under  circumstances  that  render  it  highly  probable  that  they 
were  feeding  on  a  Lepidopterous  larva  contained  in  the  stems  ; 
and  Osborn  found  a  similar  larva  that  was  pretty  certainly  a 
Mordellist$na,  and  fed  voraciously  on  Dipterous  larvae  in  the 
steins  of  a  plant.  The  little  that  is  known  as  to  the  meta- 


FIG.  IW.—Mordelli- 

stenn  tJi'i'iilensis. 
America.  (After 
Pdley.)  A,  Larva  ; 
B.  pupa  ;  C,  imago ; 
D,  outline  of  de- 
tached head  of  im- 
ago of  M.  fin  in  iln, 
to  show  the  ueck. 


morphoses  of  Mordclla  and  Anuspis   shows  that  they  live  in  old 
wood,  but  does  not  make  clear  the  nature  of  their  food. 

Although  it  has  been  ascertained  that  the  Ehipiphorides 
exhibit  instances  of  remarkable  metamorphosis,  their  life- 
histories  are  still  very  imperfectly  known.  Dr.  Chapman  has 
ascertained  some  particulars  as  to  Metoecus  paradoxns,  which  has 
long  been  known  to  prey  in  the  larval  state  on  the  larvae  of  the 
common  social  wasps.1  The  eggs  are  apparently  not  deposited  in 
the  nests  of  the  wasps,  but  in  old  wood.  The  young  larva  is  a 
triungulin,  similar  to  that  of  the  Cantharidae,  we  shall  sub- 
sequently describe.  It  is  not  known  how  it  makes  its  way  to 
the  was] is'  nests,  but  it  is  possible  that  when  a  wasp  visits  some 
old  wood  haunted  by  these  larvae,  some  of  them  may  attach 
themselves  to  it  and  be  carried  to  the  wasps'  nests.  When 

1  Ann.  Nat.  Jlisf.  (4)  vi.  1870,  p.  314  ;  and  Ent.  Mu<j.  xxvii.  1891,  p.  18. 


v  HETEROMERA CANTHARIDAE  269 

access  is  gained  to  the  cells  the  little  Metoecus  pierces  the  skin  of 
one  of  the  wasp-grubs,  and  entering  in  it  feeds  on  the  interior  ; 
after  it  has  increased  in  size  it  emerges,  changes  its  skin,  and 
assumes  a  different  form  and  habits  ;  subsequently,  as  an  external 
parasite,  entirely  devouring  the  wasp-larva,  and  then  becoming  a 
pupa,  and  finally  a  perfect  Metoecus,  in  the  cell  of  the  wasp.  The 
wasps, though  they  investigate  the  cells,  do  not  apparently  entertain 
any  objection  to  the  Metoecus,  though  there  may  be  sometimes  as 
many  as  twenty  or  thirty  of  the  destroyers  in  a  single  nest.  A 
few  hours  after  the  Metoecus  has  become  a  winged  Insect  and  has 
escaped  from  the  cells,  it  appears  however,  from  the  observations 
of  Erne  l  on  nests  of  wasps  in  captivity,  that  the  wasps  become 
hostile  to  the  foreigners,  and  it  is  probable  that  in  a  state  of 
nature  these  leave  the  nest  as  quickly  as  possible.  Emenadia 
Jitil>dlata,  a  genus  allied  to  Metoecus,  has  been  discovered  by 
Chobaut  to  have  a  similar  life-history,  except  that  it  attacks  a 
solitary  wasp  of  the  genus  Odynerus?  An  old  record  to  the 
effect  that  a  second  species  of  Emenadia,  E.  bimaculata,  lives  in 
the  stalks  of  Eryngium  campestre,  on  the  pith,  is  now  thought  to 
be  erroneous.  Fabre  has  found  the  larvae  and  pupae  of  another 
Ehipiphorid  in  the  cells  of  a  bee,  Halictus  sexcinctus. 

The  most  remarkable  of  the  Bhipiphorids,  from  the  point  of 
view  of  its  habits,  is  certainly  Symlius  blattarum,  which  is  now 
treated  as  the  same  as  an  Insect  previously  described  by  Thunberg 
from  specimens  found  in  amber  and  called  Ripidius  pectinicornis. 
This  species  is  parasitic  in  cockroaches :  the  male  and  female  are 
very  different,  the  former  being  an  active  winged  Insect,  while 
the  female  is  worm-like,  differing  but  little  from  the  larva,  and 
never  leaving  the  body  of  the  cockroach.  It  is  to  be  regretted 
that  the  life-history  is  not  better  known.  The  species  has  been 
found  on  board  ship  in  vessels  coining  from  India  ;  the  male  has 
been  met  with  in  several  European  countries,  but  the  female  is 
excessively  rare. 

Fam.  75.  Cantharidae  or  Meloidae  (Blister-beetles,  Oil -beetles'). 
—Head  with  an  abrupt  neck ;  elytra  and  sides  of  the  abdomen  witli  - 
out  any  coadaptation ;  each  claw  of  the  feet  with  a  long  ^y^"'"'/"/" 
r/o.sv///  Applied  beneath  it.  This  distinct  family  consists  of 
Heteromera  with  soft  integument,  and  is  remarkable  for  the  fact 
that  many  of  its  members  contain  a  substance  that  when  extracted 
1  Mitt.  Schu-eiz.  cut.  Ges.  iv.  1876,  p.  556.  -  Ann.  Soc.  ent.  France,  Ix.  1891,  p.  447. 


2/O  COLEOPTERA  CHAP. 

and  applied  to  the  human  skin,  possesses  the  power  of  raising 
blisters.  The  life-history  is  highly  remarkable,  the  most  complex 
forms  of  hyper-metamorphosis  being  exhibited.  The  species  now 
known  amount  to  about  1500;  there  can  be  no  difficulty  in 
recognising  a  member  of  the  family  by  the  above  characters, 
except  that  in  a  very  few  cases  each  claw  bears  a  projecting 
tooth,  instead  of  an  elongate  appendage  parallel  with  itself.  The 
penultimate  tarsal  joint  is  scarcely  ever  broader  than  the  pi'e- 
ceding ;  the  colour  and  style  of  markings  are  extremely  varied. 
There  are  two  very  distinct  sub  -  families,  Cantharides  and 
Meloides ;  the  former  are  winged  Insects,  and  are  frequently 
found  on  flowers  or  foliage.  The  Meloides  are  wingless,  and 
consequently  terrestrial ;  they  have  a  very  short  metasternum, 
so  that  the  middle  coxae  touch  the  hind  ;  and  they  also  have 
very  peculiar  wing-cases,  one  of  the  two  overlapping  the  other 
at  the  base ;  in  a  few  Meloids  the  wing  -  cases  are  merely 
rudiments. 

The  post-embryonic  development  of  these  Insects  is  amongst 
the  most  remarkable  of  modern  entomological  discoveries.  The 
first  steps  were  made  by  Newport  in  185 1,1  and  the  subject 
has  since  been  greatly  advanced  by  Fabre,  Eiley,  and  others. 
.Is  an  example  of  these  peculiar  histories,  we  may  cite  Eiley's 
account-  of  Epicauta  vittata  (Fig.  140),  a  blister-beetle  living 
at  the  expense  of  North  American  locusts  of  the  genus  Calop- 
/'  /ins.  The  locust  lays  its  eggs  underground,  in  masses  sur- 
rounded by  an  irregular  capsule,  and  the  Epicauta  deposits  its 
eggs  in  spots  frequented  by  the  locust,  but  not  in  special 
proximity  to  the  eggs  thereof.  In  a  few  days  the  eggs  of 
the  blister-beetle  hatch,  giving  rise  to  little  larvae  uf  the  kind 
called  triungulin  (Fig.  140,  A),  because  each  leg  is  terminated  by 
three  tarsal  spines  or  claws.  In  warm,  sunny  weather  these 
triungulins  become  very  active ;  they  run  about  on  the  surface 
of  the  ground  exploring  all  its  cracks,  penetrating  various  spots 
and  burrowing,  till  an  egg-pod  of  the  locust  is  met  with  :  into 
Ih is  the  triungulin  at  once  eats  its  way,  and  commences  to  devour 
an  egg.  Should  two  or  more  Iriungulins  enter  the  same  egg-pod, 
battles  occur  till  only  one  is  left.  After  a  few  days  passed  in 

"On  the  Natural  History,   Anatomy,  and   Development  of  the  Oil-Beetle, 
Meloe,  '   Tr.  LI  mi.  ,S'oe.  xx.  1851,  p.  297  ;  ami  xxi.  18.13,  p.  167. 
Rep.  U.S.  ent.  Commission,  i.  L878,  p.  297. 


HETEROMERA CANTIIARIDAE 


271 


devouring  a  couple  of  eggs,  the  triungulin  sheds  its  skin  and 
appears  as  a  different  larva  (Fig.  140,  B),  with  soft  skin,  short 
legs,  small  eyes,  and  different  form  and  proportions ;  a  second 
moult  takes  place  after  about  a  week,  Lut  is  not  accompanied  by 
any  very  great  change  of  form,  thong] i  the  larva  is  now  curved, 
less  active,  and  in  form  like  a  larva  of  Scarabaeidae ;  when 
another  moult  occurs  the  fourth  instar  appears  as  a  still  more 
helpless  form  of  larva  (Fig.  140,  D),  which  increases  rapidly 
in  size,  and  when  full  grown  leaves  the  remains  of  the  egg-pod 


FIG.  140. — Hypermetamorphosis  of  Epicauta  vittata.  North  America.  (After  Riley.) 
A,  Young  larva  or  triungulin  ;  B,  Caraboid  iustar  or  second  larva  ;  C,  coarctate 
larva,  or  instar  between  the  Scarabaeoid  and  Scolytoid  larva  ;  D,  Scarabaeoid  larva, 
from  which  the  Scolytoid,  or  sixth,  instar  differs  but  little  ;  E,  pupa  ;  F,  imago. 

it  has  been  living  on,  and  forms  a  small  cavity  near  by ;  here  it 
lies  on  one  side  motionless,  but  gradually  contracting,  till  the 
skin  separates  and  is  pushed  down  to  the  end  of  the  body,  dis- 
closing a  completely  helpless  creature  that  has  been  variously 
called  a  semi-pupa,  pseudo-pupa,  or  coarctate  larva  (Fig.  140,  C) ; 
in  this  state  the  winter  is  passed.  In  spring  the  skin  of  the 
coarctate  larva  bursts,  and  there  crawls  out  of  it  a  sixth  instar 
which  resembles  the  fourth  (Fig.  140,  D),  except  in  the  somewhat 
n-durrd  si/c  and  greater  whiteness.  It  is  worthy  of  remark  that 
the  skin  it  has  deserted  retains  its  original  form  almost  intact. 
In  this  sixth  instar  the  larva  is  rather  active  and  burrows  about. 


272  COLEOPTERA  CHAP. 

but  does  not  take  food,  and  in  the  course  of  a  few  days  again  moults 
and  discloses  the  true  pupa  (Fig.  140,  E).  As  usual  in  Coleoptera 
this  instar  lasts  but  a  short  time,  and  in  five  or  six  days  the  perfect 
beetle  appears  (Fig.  140,  F).  It  is  extremely  difficult  to  frame  any 
explanation  of  this  complex  development ;  there  are,  it  will  be 
noticed,  no  less  than  five  stages  interposed  between  the  first 
larval  instar  and  the  pupal  instar,  and  the  creature  assumes  in 
the  penultimate  one  a  quasi-pupal  state,  to  again  quit  it  for 
a  return  to  a  previous  state.  It  is  possible  to  look  on  the 
triungulin  and  the  pupal  instars  as  special  adaptations  to  external 
conditions ;  but  it  is  not  possible  to  account  for  the  intermediate 
instars  in  this  way,  and  we  must  look  on  them  as  necessitated  by 
the  physiological  processes  going  on  internally.  Nothing,  how- 
ever, is  known  as  to  these.  It  may  be  well  to  mention  that, 
after  describing  and  figuring  (lac.  cit.}  this  series  of  instars,  Eiley 
changed  his  views  as  to  their  nomenclature.1  The  following 
summary  of  the  metamorphosis,  to  which  we  have  added  the  two 
nomenclatures  of  Eiley — the  original  one,  when  different  from  the 
amended  one,  being  given  in  square  brackets — may  therefore  be 
useful,  viz. — Egg  ;  1,  triungulin-larva — moult ;  2,  Caraboid  larva 
[second  larva,  Caraboid  stage] — moult ;  3,  Scarabaeoid  larva 
[second  larva,  Scarabaeoid  stage] — moult;  4,  Scarabaeoid  laiva 
[second  larva,  ultimate  stage]  (large  amount  of  food  and  much 
growth) — moult;  5,  coarctate  larva  [pseudo-pupa,  or  semi  pupa] ; 
6,  Scolytoid  larva  [third  larva]  (active,  but  little  or  no  food  taken) 

—moult ;   7,  pupa — moult ;   8,  perfect  Insect. 

M.  Fabre  has  succeeded  in  elucidating  the  history  of  Sitaris 
Immeralis,  a  Cantharid  that  lives  at  the  expense  of  bees  of  the 
genus  Anthophora?  The  eggs  of  the  Sitaris  are  deposited  in 
the  earth  in  close  proximity  to  the  entrances  to  the  bees'  nests, 
about  August.  They  are  very  numerous,  a  single  female  pro- 
ducing, it  is  believed,  upwards  of  2000  eggs.  In  about  a  month 

-  towards  the  end  of  September  —  they  hatch,  producing  a 
tiny  triungulin  of  black  colour ;  the  larvae  do  not,  however, 
move  away,  but,  without  taking  any  food,  hibernate  in  a  heap, 
remaining  in  this  state  till  the  following  April  or  May,  when 
they  become  active.  Although  they  are  close  to  the  abodes  of 
the  bees  they  do  not  enter  them,  but  seek  to  attach  themselves 

1  Amer.  Nat.  xvii.  1883,  p.  790. 
•  For  illustration  of  this  metamorphosis,  see  Vol.  Y.  p.  159  of  this  work. 


CANTHARIDAE  2/3 


to  any  haiiy  object  that  may  come  near  them,  and  thus  a  certain 
number  of  them  get  on  to  the  bodies  of  the  AntTio-phora  and  are 
carried  to  its  nest.  They  attach  themselves  with  equal  readiness 
to  any  other  hairy  Insect,  and  it  is  probable  that  very  large 
numbers  perish  in  consequence  of  attaching  themselves  to  the 
wrong  Insects.  The  bee  in  question  is  a  species  that  nests  in 
the  ground  and  forms  cells,  in  each  of  which  it  places  honey  and 
lays  an  egg,  finally  closing  the  receptacle.  It  is  worthy  of 
remark  that  in  the  case  of  the  Anthophora  observed  by  M. 
Fabre,  the  male  appears  about  a  month  before  the  female,  and  it 
is  probable  that  the  vast  majority  of  the  predatory  larvae  attach 
themselves  to  the  male,  but  afterwards  seize  a  favourable 
opportunity,  transfer  themselves  to  the  female,  and  so  get 
carried  to  the  cells  of  the  bee.  When  she  deposits  an  egg  on 
the  honey,  the  triungulin  glides  from  the  body  of  the  bee  on  to 
the  egg,  and  remains  perched  thereon  as  on  a  raft,  floating  on 
the  honey,  and  is  then  shut  in  by  the  bee  closing  the  cell.  This 
remarkable  act  of  slipping  on  to  the  egg  cannot  be  actually 
witnessed,  but  the  experiments  and  observations  of  the  French 
naturalist  leave  little  room  for  doubt  as  to  the  matter  really 
happening  in  the  way  described.  The  egg  of  the  bee  forms  the 
first  nutriment  of  the  tiny  triungulin,  which  spends  about  eight 
days  in  consuming  its  contents ;  never  quitting  it,  because  contact 
with  the  surrounding  honey  is  death  to  the  little  creature,  which 
is  entirely  unfitted  for  living  thereon.  After  this  the  triungulin 
undergoes  a  moult  and  appears  as  a  very  different  creature,  being 
now  a  sort  of  vesicle  with  the  spiracles  placed  near  the  upper  part ;. 
so  that  it  is  admirably  fitted  for  floating  on  the  honey  (Vol.  V. 
Fig.  86,  10).  In  about  forty  days,  that  is,  towards  the  middle 
of  July,  the  honey  is  consumed,  and  the  vesicular  larva  after  a 
few  days  of  repose  changes  to  a  pseudo-pupa  (11  of  the  fig. 
cited)  within  the  larval  skin.  After  remaining  in  this  state  for 
about  a  month,  some  of  the  specimens  go  through  the  subsequent 
changes,  and  appear  as  perfect  Insects  in  August  or  September. 
The  majority  delay  this  subsequent  metamorphosis  till  the  follow- 
ing spring,  wintering  as  pseudo-pupae  and  continuing  the  series 
of  changes  in  June  of  the  following  year  ;  at  that  time  the  pseudo- 
pupa  returns  to  a  larval  form  (12  of  the  fig.  cited),  differing  com- 
paratively little  from  the  second  instar.  The  skin, though  detached, 
is  again  not  shed,  so  that  this  ultimate  larva  is  enclosed  in  two 
vor,  vi  T 


2/4  COLEOPTERA  CHAP. 

dead  skins  ;  in  this  curious  envelope  it  turns  round,  and  in  a  couple 
of  days,  having  thus  reversed  its  position,  becomes  lethargic  and 
changes   to   the   true  pupa,  and  in  about  a  month   subsequent   to 
this  appears  as  a  perfect  Insect,  at  about  the  same  time  of  the 
year  as  it  would   have   done   had   only  one  year,  instead   of  two, 
been   occupied  by   its    metamorphosis.      M.   Fabre  employs  the 
term,  third  larva,  for   the   instar  designated  by  Riley  Scolytoid 
larva,  but  this  is  clearly  an  inconvenient  mode  of  naming  the 
instar.      Sitaris   humeralis   is   now   very  rare   in   Britain,  but   it 
seems    formerly    to    have    been    more    common,    and    it    is    not 
improbable   that   its   triungulin  may   have  been   the  "  Pediculus 
meliUae,"   that  was  believed   by  Kirby  to  be  a   sort  of  bee-louse. 
Some  species  of  the  genus  Mdoe  are  still  common  in  Britain,  and 
the  Insects  maybe  seen  with  heavy  distended  abdomen  grazing  on 
herbage  in  the  spring.    The  females  are  enormously  prolific,  a  single 
one  producing,  it  is  believed,  about   10,000   eggs.      Meloe  is  also 
dependent  on  Antlwpliora,  and  its  life-history  seems  011  the  whole 
to    be    similar    to    that    of   Sitaris ;   the    eggs   are,  however,  not 
necessarily   deposited   in   the   neighbourhood   of   the    bees'   nests, 
and    the    triungulins   distribute    themselves   on   all  sorts   of  un- 
suitable Insects,  so  that  it  is  possible   that  not  more   than  one  in 
a  thousand  succeeds  in  getting  access  to  the  Antliopliora  nest.      It 
would  be  supposed  that  it  would  be  a  much  better  course  for  these 
bee-frequenting  triungulins  to  act  like  those  of  E^ncauta,  and  hunt 
for  the  prey  they  are  to  live  on  ;  but  it  must  be  remembered  that 
they  cannot  live  on  honey  ;   the  one  tiny  egg  is  their  object,  and 
this  apparently  can  only  be  reached  by  the  method  indicated  by 
Fabre.      The    history   of  these   Insects    certainly    forms    a    most 
remarkably    instructive    chapter    in   the    department    of    animal 
instinct,  and  it  is  a  matter   for   surprise   that   it  should   not  yet 
have  attracted  the  attention  of  comparative  psychologists.      The 
series   of    actions,    to    be    performed    once  and    once   only    in    a 
lifetime  by  an  uniiistructed,  inexperienced  atom,  is  such  that  we 
should   a  2]r'iori   have   denounced   it  as  an  impossible   means   of 
existence,  were  it  not  shown   that  it  is  constantly  successful.      It 
is  no  wonder   that   the   female  Jfeloe  produces  5000  times  more 
eggs  than  are  necessary  to  continue  the  species  without   diminu- 
tion  in   the   number  of  its  individuals,   for    the   first  and  most 
important    act   in    the    complex    series    of    this    life  -  history    is 
accomplished    by    an    extremely    indiscriminating    instinct;     the 


HETEROMERA  275 


newly  hatched  3Moe  has  to  get  on  to  the  body  of  the  female  of 
one  species  of  bee  ;  but  it  has  no  discrimination  whatever  of  the 
kind  of  object  it  requires,  and  as  a  matter  of  fact,  passes  with 
surprising  rapidity  on  to  any  hairy  object  that  touches  it ;  hence 
an  enormous  majority  of  the  young  are  wasted  by  getting  on  to 
all  sorts  of  other  Insects ;  these  larvae  have  been  found  in 
numbers  on  hairy  Coleoptera  as  well  as  on  flies  and  bees  of  wrong 
kinds  ;  the  writer  has  ascertained  by  experiment  that  a  camel's- 
hair  brush  is  as  eagerly  seized,  and  passed  on  to,  by  the  young 
Mdoe  as  a  living  Insect  is. 

The  histories  of  several  other  Cantharids  have  been  more  or 
less  completely  discovered.  Fabre  has  found  the  larva  of 
Germ-milt/,  schaefferi  attacking  the  stores  of  provisions  laid  up  by 
a  fossorial  wasp  of  the  genus  Tacliytes,  and  consisting  of 
Orthoptera  of  the  family  Mantidae.  The  student  who  wishes 
for  further  information  may  refer  to  M.  Beauregard's  work  on 
this  family.1 

Some  half-dozen  species  of  the  genus  Ceplialoon  found  in 
Siberia,  Japan,  and  North  America,  have,  by  some  authorities, 
been  separated  as  the  family  Cephaloidae.  Nothing  is  known 
as  to  the  metamorphosis  of  these  rare  beetles ;  and  at  present  it 
is  not  necessary  to  distinguish  them  from  Cantharidse. 

Fam.  76.  Trictenotomidae. — Large  Heteromera,  with  powerful 
free  projecting  mandibles  ;  the  antennae  long,  but  with  the  termi  mil 
three  joints  short,  with  angular  projections  on  one  side.  This 
family  includes  only  two  genera  and  seven  or  eight  species. 
They  are  very  remarkable  Insects ;  Autocrates  aenea  being  three 
inches  long.  The  family  is  of  considerable  interest,  as  it  seems  to 
have  no  affinity  with  any  other  Coleoptera.  The  appearance  of 
the  species  somewhat  reminds  one  of  Lucanidae,  or  Prionides ; 
but  Trictenotomidae  have  even  less  relation  to  those  beetles  th;in 
they  have  to  the  members  of  the  Heteromerous  series.  The 
Trictenotomidae  appear  to  be  found  only  in  the  primitive  forests 
of  the  Indian  and  Indo-Malayan  regions.  Nothing  is  known  as 
to  their  life-histories. 

1  Les   Inscctcs   Vesicants,   Paris    1890,    554   pp.     Parts  of  this  work  were  pre- 
viously published  in  J.  de  I'Anat.  Phys.,  xxi.  xxii.  xxiii.  1886  and  1SS7. 


2/6  COLEOPTERA 


CHAP. 


Series  V.   Phytophaga. 

Tarsi  apparently  four-jointed,  the  three  basal  joints  usually  densely 
set  with  cushion -like  pubescence  beneath;  the  third  joint 
different  in  form,  being  divided  into  two  lobes,  or  grooved 
on  its  upper  surface  so  as  to  allow  of  tit  e  fourth  joint  being 
inserted  near  its  base  instead  of  at  its  extremity.  Head  not 
forming  a  definite  prolonged  beak ;  its  labrum  visible,  the 
palpi  rarely  (and  even  then  not  con^letcly}  occluded  in  the 
mouth. 

This  great  series  of  beetles  includes  something  like  35,000 
species.  It  approaches,  like  all  the  other  series,  the  Polymorpha, 
especially  the  family  Erotylidae  placed  therein,  Imt  in  the  great 
majority  of  cases  there  is  no  difficulty  in  recognising  its 
members.  The  tarsi  have  never  the  Heteromerous  formula,  the 
head  is  not  constructed  like  that  of  Ehyuchophora,  nor  the 
mouth  and  feet  like  those  of  Adephaga ;  the  antennae  are 
different  from  those  of  the  Lamellicorns.  The  tarsi  are  really 
five-jointed,  for  careful  inspection  shows  that  the  long  claw-joint 
has  at  its  extreme  base  a  small  nodule,  which  is  undoubtedly 
the  fourth  joint  (Fig.  142,  B).  In  speaking  of  the  joints  it  is, 
however,  customary  not  to  refer  to  this  small  and  functionally 
useless  joint  at  all,  and  to  call  the  claw-joint  the  fourth  ;  when 
the  little  joint  is  referred  to  it  may  be  called  the  true  fourth 
joint, 

Nearly  the  whole  of  the  enormous  number  of  species  of  this 
series  are  directly  dependent  on  the  vegetable  kingdom  for 
their  nutriment ;  they  are  therefore  well  styled  Phytophaga. 
This  term  is,  however,  restricted  by  some  systematists  to  the 
family  we  have  called  Chrysomelidae.  Although  there  is 
enormous  variety  in  this  series,  three  families  only  can  be  at  all 
naturally  distinguished,  and  this  with  difficulty.  Of  these  the 
Bruchidae  are  seed -feeders,  the  Chrysomelidae,  as  a  rule,  leaf- 
feeders,  the  Cerambycidae  wood  and  stem-feeders.  The  number  of 
exceptions  to  this  rule  is  but  small,  though  certain  Cerambycidae 
and  certain  Chrysomelidae  live  on  roots. 

Fam.  77.  Bruchidae. — Prosternum  extremely  short ;  in  front 
perpendicular;  behind  the  coxae,  forming  merely  a  transverse 
lamina  with  pointed  extremity.  Hind  femora  more  or  less 


PHYTOPHAGA — BRUCHIDAE 


2/7 


thickened.  This  comparatively  small  family  includes  about 
70  0  species  of  small,  unattractive  beetles.  The  larvae  live  in 
seeds  ;  hence  some  of  the  species  are  liable  to  be  transported  by 
means  of  commerce  ;  some  of  them  do  considerable  injury  ;  peas 
and  beans  being  specially  subject  to  their  attacks.  They  are 
able  to  complete  their  growth  with  a  very  small  amount  of 
nutriment,  some  of  them  consuming  only  a  portion  a  little  larger 
than  themselves  of  a  bean  or  pea.  The  larvae  are  fat  maggots 
without  legs,  but  Riley  has  discovered  that  the  young  larvae  of 
Bruclius  pisi  and  B.  fabae  have,  when  first  hatched,  three  pairs 
of  legs  which  are  subsequently  lost.  They  also  have  peculiar 


FIG.  \±\.—Bn>clivs 
pisi  or  pea-weevil. 
A,  Young  larva  ; 
B.protlioracie  spin- 
ous  process  ;  C, 
post-embr  yonic 
leg,  greatly  magni- 
fied. ;  D,  pea-pod, 
with  tracks  of 
entry  ;  E,  portion 
of  pod,  with  egg, 
and  the  '  subse- 
quently formed 
track,  magnified  ; 
F,  imago.  (After 
Riley.) 


spinous  processes  on  the  pronotum.  Both  of  these  characteristics 
may  be  correlative  with  the  transient  differences  in  the  activities 
of  the  larva,  for  the  little  creature  is  not  at  first  located  in  the 
pea,  but  mines  a  gallery  in  the  pod,  in  which  it  moves  about, 
subsequently  entering  the  pea  and  losing  its  legs.  There  is  a 
good  deal  of  difference  in  these  respects  between  the  two  species 
— B.  pisi  and  B.  fabae — examined  by  Riley,  and  as  but  little  is 
known  of  the  life-histories  of  other  Bruchidae  it  is  probable  that 
still  greater  variety  prevails.  Heeger  has  found  that  Bruclius 
lentis  sometimes  requires  two  seeds  to  enable  it  to  complete  its 
growth  ;  it  is,  notwithstanding  its  legless  state  when  half-grown, 
able  to  migrate  by  dropping  to  the  earth,  and  dragging  itself 
along  by  its  mandibles  till  it  conies  to  another  pod  into  which  it 
bites  its  way. 

The   family  has,  until  recently,  been  placed  in   the  Rhyncho- 


2/0 


COLEOPTERA 


CHAP. 


phorous  series,  with  which  it  has,  however,  no  direct  connection. 
On  the  other  hand,  it  is  so  closely  connected  with  Chrysomelidae 
that  it  is  not  possible  to  indicate  good  characters  to  distinguish 
the  two  at  present.  The  Australian  genus  Carpophagus,  and  the 
large  South  American  species  of  Garydborus  appear  to  be  quite 
indistinguishable  as  families,  though  Lacordaire  and  Chapuis 
placed  one  in  Bruchidae,  the  other  in  Chrysomelidae.  The 
definition  we  have  given  applies,  therefore,  to  the  majority  of  the 
family,  but  not  to  the  aberrant  forms  just  mentioned.  The 
European  genus  Urodon  appears  to  belong  to  Anthribidae,  not  to 
Bruchidae.  The  family  Bruchidae  is  called  Mylabridae  by  some. 
Fam.  78.  Chrysomelidae. — Antennae  moderately  long ;  eyes 
moderately  I// rt/r,  usu  filly  not  at  all  surrounding  the  insertion  of  tlir 
antennae;  upper  surface  usually  bare,  frequently  brightly  coloured 
a  ml  shining.  This  enormous  family  comprises  about  18,000 
species  of  beetles,  in  which  the  form  and  details  of  structure 
are  very  varied.  No  satisfactory  character  for  distinguishing 
5  Chrysomelidae  from  Cerambycidae  has 

^e^  ^een  disco  vered,  although  the  two 
families  are  certainly  distinct  and 
natural.  Most  of  the  Chrysomelidae 
live  on  foliage  ;  few  of  them  are  more 
than  half  an  inch  long,  whereas  the 
Cerambycidae  are  wood  -  feeders  and 
usually  of  more  elongate  form  and  larger 
size.  The  potato  beetle,  or  Colorado  beetle, 
that  occasioned  so  much  destruction  in 
North  America  some  thirty  years  ago,and 
the  introduction  of  which  into  Europe 
was  anticipated  with  much  dread,  is  a 
good  example  of  the  Chrysomelidae.  The 
turnip  flea,  a  tiny  hopping  beetle,  is 

FIG.     [4-2. — Doryphoru     decent-  J 

i  in  fit  ta,   the   potato   beetle,  among  the  smallest  forms  of  the  family. 

rSndTi.   \InS  a»d  is  »  member  of  another  very  exten- 
joint ;  •!,  true  fourth  joint ;  sive  subdivision  of  Chrysomelidae,  viz. 

[>,  so-called  fourth  joint.  TT    it-    •  i  TU  -r»i  i 

Halticides.      The    term    Phytophaga    is 

by  many  naturalists  limited  to  Chrysomelidae,  the  Cerambycidae 
being  excluded.  The  classification  of  the  family  is  but  little 
advanced,  but  the  enormous  number  of  species  of  Chrysomelidae 
are  placed  in  four  divisions,  viz.  :— 


v  PHYTOPHAGA CHRYSOMELIDAE   .        279 

Prothorax  much  narrower  at  the  base  than  the  elytra,  and  usually  with- 
out side-margins  (raised  edges).  Sub-fain.  1.  EUPODA  ;  with  three  divisions, 
Sagrides,  Donaciides,  Criocerides. 

The  basal  ventral  plates  of  the  abdominal  segments  are  somewhat  shorter 
in  tlie  middle  than  at  the  sides,  the  fourth  one  being  often  invisible  in  the 
middle,  while  the  fifth  is  very  large.  Sub-fam.  2.  CAMPTOSOJIES  ;  with  six 
divisions,  Megascelides,  Megalopides,  Clythrides,.Cryptocephalides,  Chlamydes, 
Sphaerocarides. 

In  the  other  two  groups  there  is  no  great  disparity  between  the  fourth 
and  fifth  ventral  plates. 

Prothorax  not  greatly  narrower  at  the  base  than  the  elytra,  and  usually 
with  distinct  edges  at  the  outsides.  Sub-fam.  3.  CYCLICA  ;  with  four  divi- 
sions, Lainprosomides,  Eumolpides,  Chrysomelides,  Galerucides. 

Front  of  the  head  bent  downwards  or  inflexed,  so  that  the  mouth  is  on 
the  lower  aspect.  Antennae  inserted  close  together  on  the  most  anterior 
I'-ul  of  the  head,  so  that  they  are  more  forward  than  the  mouth.  Sub-fam. 
4.  CRYPTOSTOMES  ;  with  two  divisions  Hispides,  Cassidides. 

In  the  other  three  divisions  the  mouth  is  placed  as  usual,  but  the  insertion 
<pf  the  antennae  varies  a  good  deal. 

The  larvae  of  about  100  species  of  the  family  are  known: 
they  are  arranged  in  accordance  with  their  habits,  by  Chapuis,1 
in  six  groups,  viz.  : 

1.  Elongate  larvae,  living  under  water,  and  there  undergoing  their  meta- 
morphosis. (Donaciides.) 

•2.  Larvae  mining  in  leaves,  and  undergoing  their  metamorphosis  in  the 
leaf.  (Hispides  and  some  Halticide-. 

3.  Short  convex  larvae,  frequently  with  leathery  and  pigmented  integuments, 

living  exposed  on  plants.     (Most  of  the  Cyclica.) 

4.  Larvae  of  short  form  ;   covering   the    body  with  excrementitious  matter. 

(Some  Criocerides.) 
o.   Peculiar   larvae   of  short    form,    spiny,    and    protecting    their   bodies   by 

excrementitious  matter  attached  by  a  special  apparatus,  the  excrement 

itself  being  modified  so  as  to  be  suitable  for  retention.      (Cassidides.) 
6.   Elongate,  pallid,  -larvae  with  curved  abdomen  ;  living  in  shell-like  case.-, 

and   undergoing  metamorphosis  therein.       (Most  of  the   Camptosomes, 

the  habits  of  which  are  known.) 

Though  our  knowledge  of  these  larvae  extends  to  only  about 
100  out  of  18,000  species,  the  above  category  by  no  means 
includes  all  the  kinds  of  larvae  ;  Captain  Xambeu  having 
recently  discovered  that,  the  larva  of  Chrysochus  pretiosus  HVQS  in 
the  earth  feeding  on  roots  after  the  manner  of  a  Rhizotroyn* 
larva,  which  it  resembles.  The  larva  uf  Xnym  splcndida  lives 


Genera  dcs  CoUopteres  (Suites  «  7>'////'n/().  x.  Paris.  1874,  p.  15. 


280  COLEOPTERA 


CHAP. 


inside   the  stems   of  Dioscorea  batatas,  in   swellings ;    the   group 
Sagrides,  to  which  it  belongs,  is  a  very  anomalous  one. 

i.  EUPODA.  The  beetles  of  the  genus  Donacia  are  of  special 
interest.  They  form,  with  the  genus  Haemonia,  a  peculiar  group, 
wrell  represented  in  Europe,  and  also  in  our  own  country.  They  are 
all  connected  with  aquatic  plants,  the  species  of  Haemonia  living 
entirely  under  water,  while  the  Donacia,  live  in  the  imago-state 
an  aerial  life ;  though  many  of  them  enter  the  water  with  great 
readiness,  and,  it  is  said,  are  able  to  take  wing  from  the  surface. 
The  larvae  live  011  the  roots  of  aquatic  plants,  and  derive  not  only 
nutriment  but  air  therefrom  ;  they  pass  several  months  as  pupae 
(or  as  resting  larvae  waiting  for  pupation),  under  water  in  cocoons 
which  they  construct,  and  which,  incredible  as  it  may  seem,  are 
filled  with  air,  not  water.  Exact  details  as  to  the  construction 
of  these  cocoons  are  wanting.  It  was  formerly  absurdly  supposed 
that  the  larva  swelled  itself  out  to  the  size  of  the  cocoon  it  was 
about  to  make,  and  so  served  as  a  mould,  subsequently  con- 
tracting. The  observations  of  Schmidt-Schwedt l  make  it,  however, 
more  probable  that  the  plant  itself  furnishes  the  air  which,  under 
pressure  of  the  water  (so  he  supposes),  fills  the  cocoon  ;  the  larva 
wounds  the  root,  piercing  to  an  air-vessel  and  then  constructs 
the  cocoon  on  this  spot,  leaving  to  the  last  moment  an  orifice, 
according  to  Schmidt,  as  an  exit  for  the  water.  The  larva  uses 
a  similar  artifice  for  obtaining  air;  it  has  no  gills,  but  is  pro- 
vided near  the  extremity  of  the  body  with  two  sharp  chitinous 
processes  which  it  drives  into  the  root  of  the  plant  till  it 
penetrates  an  air-vessel.  Schmidt  thinks  the  processes  serve  as 
conduits  to  conduct  the  air  to  the  tracheae,  but  Dewitz  thinks 
the  air  enters  the  larva  in  a  more  normal  manner,  by  means  of  a 
stigma  placed  at  the  base  of  the  piercing  process.  A  similar 
larva  exists  in  Haemonia  ;  which  genus  is  additionally  interesting 
from  the  fact  that  the  imago  lives  entirely  submerged.  It  is 
not  known  how  it  breathes.  This  genus  is  the  only  member  of 
the  Chrysomelidae  that  does  not  possess  the  structure  of  the 
feet  that  is  characteristic  of  the  Phytophaga.  The  late  Professor 
Babington  about  sixty  years  ago  found  H.  curtisi  at  Cley  on 
the  Norfolk  coast  on  submerged  Potamoycton  pectinatus,  but  it  has 
not  been  met  with  there  for  a  great  many  years. 

The  larvae  of  Criocerides  are  of  two  kinds,  in  one  of  which  the 

1  JJ.Tliti.  ent.  Zdt.  1887,  i>.  o25,  and  1889,  p.  299. 


PHYTOPHAGA CHRYSOMELIDAE 


281 


body  is  peculiarly  shaped  in  conformity  with  the  curious  habit 
of  using  the  excrement  as  a  covering.  The  larva  is  less  elon- 
gate than  usual,  and  has  the  anus  placed  on  the  upper  surface, 
and  formed  so  that  the  excrement  when  voided  is  pushed  forward 
on  to  the  Insect ;  here  it  is  retained  by  means  of  a  slimy  matter, 
and  a  thick  coat  entirely  covering  the  creature,  is  ultimately 
formed.  The  larva  of  Lcma  melanopa  is  not  uncommon  about 
Cambridge,  where  it  feeds  on  the  leaves  of  growing  corn.  It  is 
a  remarkable  fact  that  even  in  one  genus  the  species  have  some 
of  them  this  habit,  but  others  not.  The  species  of  Crioceris 
living  on  lilies — C.  merdiyera, 
e.g.  — are  noted  for  possessing  it ; 
while  C.  asparagi  does  not  pro- 
tect itself  in  this  way,  but  emits 
fluid  from  its  mouth  when  dis- 
turbed. This  larva  is  a  serious 
nuisance  in  some  localities  to  the 
cultivators  of  asparagus.  The 
eggs  are  deposited  on  the  stems 
of  the  plant — as  shown  in  our 
figure — sometimes  in  great  num- 
bers. 

The  perfect  Insects  of  many 
of  the  Criocerides  possess  a  stridu- 
latiug  organ.  Two  contiguous 
areas  at  the  base  of  the  last 
dorsal  segment,  where  they  can 
be  rubbed  by  the  tips  of  the 
elytra,  are  slightly  elevated  and 
bear  very  close  and  tine  straight 
lines. 

ii.  The  CAMPTOSOMES,  as  we  have  already  noticed,  are  distin- 
guished by  a  peculiar  structure  of  the  abdomen.  This  character 
appears  to  be  connected  with  a  very  remarkable  habit,  viz.  the 
formation  of  a  case  to  envelop  the  egg.  The  tip  of  the  abdomen 
is  somewhat  curved  downwards,  and,  in  the  female,  bears  a 
hollow  near  the  extremity  ;  when  an  egg  is  extruded  the  female 
holds  it  in  this  hollow  by  means  of  the  hind  legs,  and 
envelops  it  with  a  covering  said  to  be  excrementitious.  When 
the  larva  hatches,  it  remains  within  this  case,  and  subse- 


FIG.  143. — Crioceris  asparagi.  A,  Eggs 
in  position  on  stem  of  asparagus  ;  B, 
one  egg  much  enlarged  ;  C,  young 
larva. 


Cambridge. 


282  COLEOPTERA 


CHAP. 


quently  enlarges  it  by  additions  from  its  own  body.  The 
beautiful  Insects  of  the  genus  Cryptocephalus,  which  is  fairly 
well  represented  in  Britain,  belong  to  this  division.  The 
exotic  group  Megalopodes  is  incorrectly  placed  in  Camptosomes ; 
the  side  pieces  of  the  prothorax  meet  in  it  behind  the  middle 
coxae,  as  they  do  in  Khynchophora.  The  species  of  Megalopodes 
stridulate  by  means  of  an  area  on  the  base  of  the  meso-scutellum 
rubbed  by  a  ridge  inside  the  pronotum,  as  in  the  Cerambycida?. 

iii.  The  division  CYCLICA  includes  the  great  majority  of  Chryo- 
melidae ;  we  have  not  less  than  170  species  in  Britain.  The 
larvae  live,  like  those  of  Lepidoptera,  at  the  expense  of  foliage, 
and  the  species  frequently  multiply  to  such  an  extent  as  to  be 
injurious.  Some  of  them  are  destroyed  in  great  numbers  by 
Hymenopterous  parasites,  the  Braconid  genus  Perilitus  being  one 
of  the  best  known  of  these ;  in  some  cases  the  parasite  deposits 
its  eggs  in  either  the  larva  or  perfect  Insect  of  the  beetle,  and 
the  metamorphoses  of  the  parasites  in  the  latter  case  are  some- 
times, if  not  usually,  completed,  the  larvae  emerging  from  the 
living  beetles  for  pupation. 

iv.  The  CRYPTOSTOMES,  though  comparatively  few  in  number 
of  species,  include  some  very  remarkable  beetles.  There  are  two 
groups,  Hispides  and  Cassidides.  The  former  are  almost  peculiar 
to  the  tropics  and  are  not  represented  by  any  species  in  the 
British  fauna.  The  head  in  this  group  is  not  concealed  ;  but  in 
the  Cassidides  the  margins  of  the  upper  surface  are  more  or  less 
expanded,  so  that  the  head  is  usually  completely  hidden  by  the 
expansion  of  the  pronotum.  Both  the  groups  are  characterised 
by  the  antennae  being  inserted  very  near  together,  and  by  the 
short  claw-joint  of  the  feet.  Hi  spa  is  one  of  the  most  extensive 
of  the  numerous  genera  of  Hispides,  and  is  remarkable  from  the 
imago  being  covered  on  the  surface  with  long,  sharp  spines.  But 
little  is  known  as  to  the  metamorphosis,  beyond  the  fact  already 
alluded  to,  that  the  larvae  of  several  species  mine  the  interior  of 
leaves.  The  larva  of  Hispa  testacea,  according  to  Ferris,1  makes 
use  of  the  leaves  of  Cistus  salvifolius  in  Southern  Europe  ;  it  is 
broad  and  flat,  and  possessed  of  six  short  legs.  The  eggs  are  not 
deposited  by  the  parents  inside  the  leaves,  but  are  probably 
attached  to  various  parts  of  the  plant.  After  hatching,  the  young 
larva  enters  a  leaf,  and  feeds  on  the  parenchyma  without  rupturing 

1  Ann.  Soc.  Lie'/jc,  x.  1855,  p.  260. 


PHYTOPIiAGA CHRVSOMELIDAE 


283 


the  epidermis  ;  but  when  it  has  consumed  about  three-fourths  of 
the  soft  interior  of  the  leaf  it  ruptures  the  epidermis  of  the  upper 
surface,  and  seeks  another  leaf;  this  found,  it  places  itself  on  the 
midrib,  tears  the  upper  epidermis,  and  lodges  itself  in  the  leaf. 
In  the  case  of  this  second  leaf  it  attacks  the  parenchyma  in  the 
neighbourhood  of  the  petiole,  and  so  forms  an  irregular  tube 
which  has  an  open  mouth,  the  point  of  entry.  In  this  tube  it 
undergoes  its  metamorphosis.  Each  larva,  it  is  said,  alw;iy- 
makes  use  of  two  leaves,  and  of  two  opposed  leaves.  A  know- 
ledge of  the  habits  of  some  of  the  larger  of  the  exotic  Hispicles 
would  be  of  much  interest. 


FIG.  144.  — Pupa  of 
C ass id id  beetle 
(?  AspidomorjiJi" 
s  p.).  A,  With 
appendage  ex- 
tended ;  B,  with 
the  appendage  re- 
posing on  the  back. 
New  Britain. 


The  Cassidides,  in  addition  to  the  curious  marginal  expansion 
of  their  upper  surface,  have  the  power  of  withdrawing  the  head 
into  the  thorax,  and  hence  they  are  often  called  shield  or  tortoise- 
beetles.  They  exhibit  considerable  variety  in  form  and  colour, 
and  some  of  them  display  a  peculiar  metallic  reflection  of  great 
delicacy  and  beauty ;  this  disappears  entirely  after  death,  but  it 
may  be  restored  by  thoroughly  moistening  the  dead  Insect.  The 
colour,  therefore,  probably  depends  on  the  presence  of  water  in 
the  integument.  The  larvae  of  Cassidides  are  notorious  on 
account  of  their  habit  of  covering  their  bodies  with  dried 
excrement,  for  which  purpose  they  are  provided  with  a  forked 


284  COLEOPTERA  CHAP. 

process  at  the  posterior  extremity;  this  serves  to  place  the  pro- 
tecting matter  in  a  proper  position  and  to  retain  it  there.  The 
excrement  assumes  in  various  species  forms  so  peculiar  that  they 
cannot  be  considered  merely  incidental.  In  several  species  this 
covering-matter  is  like  lichen.  This  is  the  case  with  Dolichotoma 
jxil iinn-tnii,  the  larva  of  which  has,  in  place  of  the  usual  fork,  a 
more  complex  appendage  on  the  hack  for  the  purpose  of  prepar- 
ing and  retaining  its  peculiar  costume.  The  pupae,  too,  some- 
times retain  the  larval  skin.  An  extremely  remarkable  pupa  of 
a  Cassidid — possibly  of  the  genus  Aspidomorplia — was  recently 
found  by  Dr.  Arthur  Willey  in  New  Britain  (Fig.  144).  The 
back  of  the  pupa  is  covered  with  a  complex  appendage,  so  that 
the  creature  has  no  resemblance  to  an  Insect ;  this  appendage  is 
perhaps  capable  of  being  moved,  or  even  extended  (Fig.  144,  A), 
during  life.  Whether  it  may  be  formed  by  the  retention  of 
portions  of  the  moulted  gkins  of  the  larva  we  cannot  say  with 
certainty. 

The  most  remarkable  of  the  Cassidid  coverings  yet  discovered 
are  those  formed  by  certain  small  beetles  of  the  tropical  Ameri- 
can genus  Porpliyraspis.  P.  trtstts  is  apparently  a  common 
Insect  at  Bahia,  where  it  lives  on  a  cocoa-palm.  The  larva  is 
short  and  broad,  and  completely  covers  itself  with  a  very  dense 
coat  of  fibres,  each  many  times  the  length  of  the  body,  and 
elaborately  curved  so  as  to  form  a  round  nest  under  which  the 
larva  lives.  On  examination  it  is  found  that  these  long  threads 
arc  all  attached  to  the  anal  extremity  of  the  Insect,  and  there 
seems  no  alternative  to  believing  that  each  thread  is  formed  by 
small  pieces  of  fibre  that  have  passed  through  the  alimentary  canal, 
and  are  subsequently  stuck  together,  end  to  end.  The  process  of 

forming  these  long  fibres,  each  one  from 
scores  of  pieces  of  excrement,  and  giving 
them  the  appropriate  curve,  is  truly  remark- 
able. The  fibres  nearest  to  the  body  of  the 
larva  are  abruptly  curled  so  as  to  fit  exactly, 
FIG.  1-45.— Nest  of  intes-  and  make  an  even  surface  ;  but  the  outside 

finally-made    filaments    fij  fc       d  fc      j  somewhat      busllV 

under  winch  the  larva    ' 

of  Poi-j>Jii/ri(yj>i.-i  trintis  fashion.      The  construction  is  much  like  that 
of  a  tiny  bird's  nest.    Senor  Lacerda  informed 

the  writer  that  the  larva  makes  a  nest   as   soon  as  it  is  hatched. 
Another   2><>fpJn/fitsj>is--P.    palmarum- -lasts   been    recorded    as 


PHYTOPHAGA CERAMBYCIDAE 


285 


forming  similar  nests  on  a  species  of  Thrinax  in  St.  Domingo. 
Candeze  says  l  that  when  it  lias  completed  its  growth  the  larva 
ejects  on  to  the  leaf  a  quantity  of  semi-liquid  matter,  and  this,  on 
drying,  sticks  the  nest  to  the  leaf,  so  that  the  metamorphosis  is 
effected  under  shelter. 

Fam.  79.  Cerambycidae  (Longicorns). — Form  usually  oblong, 
not  much,  curved  in  outline  at  the  sides;  surface  very  frequent! '//  ren- 
dered dull  by  a  very  minute  hairiness,  which  often  forms  a  /»///*/•//  ; 
antennae  usually  long,  and  their  insertion  much  embraced  by  ///*' 
eyes.  This  great  family  of  beetles  includes  some  12,000  or 
13,000  known  species.  The  elegance  and  variety  of  their  forms 
and  the  charm  of  their  colours  have  caused  them  to  attract  much 
attention,  so  that  it  is  probable  that  a  larger  proportion  of  the 
existing  species  have  been  obtained  than  is  the  case  in  any  other 
of  the  great  families  of  Coleoptera.  Still 
it  is  not  likely  that  one-half  of  the  living- 
forms  are  known.  It  is  not  possible  at 
present  to  point  out  any  one  character  of 
importance  to  distinguish  Cerambycidae 
from  Chrysomelidae,  though  the  members 
of  the  two  families  have,  as  a  rule,  but 
little  resemblance  in  external  appearance. 
Most  of  them  live  on,  or  in,  wood,  though 
many  are  nourished  in  the  stems  of  her- 
baceous plants.  The  larvae  live  a  life  of  con- 
cealment, and  are  soft,  w^hitish  grubs  with 

powerful  mandibles,  and  usually  with  a  comparatively  small  head, 
which  is  not  much  exserted  from  the  thorax.  Most  of  them  are 
without  legs,  but  a  good  many  have  three  pairs  of  small  legs,  and 
there  are  numerous  cases  in  which  the  surface  of  the  body  is 
furnished  above  or  below  with  swellings  believed  to  act  as 
pseudopods  (Fig.  84),  and  help  the  larvae  to  move  about  in  their 
galleries ;  but  this  is  probably  not  the  sole  function  of  these 
organs,  as  their  surface  is  varied  in  character,  and  often  not  of  a 
kind  that  appears  specially  adapted  to  assist  in  locomotion. 
There  is  a  slight  general  resemblance  between  the  larvae  of  Ceram- 

O  O 

bycidae  and  those  of  Buprestidae,  and  when  the  thorax  of  a 
Lougicorn  larva  is  unusually  broad,  e.g.  Asiynomus,  this  similarity 
is  very  pronounced. 

1  Mem.  Soc.  LUge,  xvi.  1861,  p.  387. 


1H! 


286  COLEOPTERA 


CHAT. 


The  modes  of  life  of  Cerambycid  larvae  exhibit  considerable 
variety,  and  much  perfection  of  instinct  is  displayed  by  the  larvae, 
as  well  as  by  the  mother  beetles.  The  larvae  of  Saperda  popidnea 
are  common  in  certain  woods  in  the  South  of  England  in  the 
stems  of  aspen ;  they  consume  only  a  small  quantity  of  the 
interior  of  the  stem,  and  are  probably  nourished  by  an  afflux  of 
sap  to  the  spot  where  they  are  situated.  Elapliidion  villosum  is 
called  the  oak-primer  in  Xorth  America.  The  parent  beetle  lays 
an  eiro'  near  the  axilla  of  a  leaf-stalk  or  small  stem,  and  the 

oo 

young  larva  enters  this  and  feeds  on  the  tender  material ;  as  it 
grows  it  enters  a  larger  limb,  and  makes  an  incision  within  this 
in  such  a  manner  that  the  wood  falls  to  the  ground  with  the 
larva  within  it,  the  dead  wood  serving  subsequently  as  pa-bulum 
and  as  a  shelter,  within  which  the  metamorphosis  is  completed. 
The  species  of  the  American  genus  Oncideres  are  called  girdlers, 
because  the  parent  beetle,  after  laying  an  egg  in  a  small  branch, 
girdles  this  round  with  a  deep  incision,  so  that  the  portion 
containing  the  larva  sooner  or  later  falls  to  the  ground.  The 

O  O 

growth  of  a  Longicorn  larva  frequently  takes  more  than  a  year, 
and  under  certain  circumstances  it  may  be  enormously  prolonged. 
Monohammus  confusus  has  been  known  to  issue  from  wooden 
furniture  in  a  dwelling-house  when  the  furniture  was  fifteen 
years  old.  Individuals  of  another  Longicorn  have  issued  from 
the  wood  of  a  table,  twenty  and  even  twenty-eight  years  after  the 
felling  of  the  tree  from  which  the  furniture  was  made.  Sereno 
Watson  has  related  a  case  from  which  it  appears  probable  that 
the  life  of  a  Longicorn  beetle  extended  over  at  least  forty-five 
years.1  It  is  generally  assumed  that  the  prolongation  of  life  in 
these  cases  is  due  to  the  beetle  resting  quiescent  for  long  after  it 
has  completed  the  metamorphosis.  Recent  knowledge,  however, 
renders  it  more  probable  that  it  is  the  larval  life  that  is  pro- 
longed ;  the  larva  continuing  to  feed,  but  gaining  little  or  no 
nutriment  from  the  dry  wood  in  these  unnatural  conditions.  Mr. 
C.  0.  TVaterhouse  had  for  some  years  a  Longicorn  larva  under 
observation,  feeding  in  this  way  in  the  wood  of  a  boot-tree  ;  ~  the 
burrows  in  the  wood  contained  a  great  deal  of  minute  dust 
indicating  that  the  larva  passed  much  matter  through  the  ali- 
mentary canal,  probably  with  little  result  in  the  way  of  nutriment. 

1  Packard,  5th  Rep.  U.S.  Ent.  Comm.  1S90,  p.  689. 
-  Xot  a  growing  tree,  but  the  instrument  used  for  stretching  boots. 


HYTOPHAGA CERAMBYCIDAE  287 

There  are  numerous  Longicorns  that  bear  a  great  resemblance 
in  form  and  colour  to  Insects  to  which  they  are  not  related. 
Haensch  J  has  noticed  that  species  of  the  genus  Odontocera 
resemble  various  Hymenoptera,  one  species  being  called  0. 
braconoides;  he  also  observed  that  these  Hymenoptera  -  like 
Longicorus,  instead  of  withdrawing  their  underwings  under  the 
elytra  as  beetles  generally  dn.  vibrate  them  rapidly  like  Hyn;en- 
"ptera.  A  large  number  of  Loiigicnrn-  ,-tridulate  loudly  by  rubbing 
a  ridge  inside  the  pronotum  on  a  highly  specialised,  striate  >urf;i<-e 
at  the  base  of  the  scutellum,  and  therefore  covered  up  when  the 
Insect  is  contracted  in  repose.  A  few  produce  noise  by  rubbing 
the  hind  femora  against  the  edges  of  the  elytra,  somewhat  after 
the  fashion,  of  grasshoppers.  In  this  case  there  appears  to  be 
comparatively  little  speciality  of  structure,  the  femora  bearing, 
however,  more  or  less  distinct  small  granules.  The  species  of  the 
Hawaiian  genus  Plagithmysus  produce  sound  in  both  these 
manners,  the  thoracic  stridulating  organ  being  beautifully  de- 

o         o  o  */ 

velupcd,  while  in  some  species  the  margin  of  the  elytra  and 
b:;se  of  the  femora  are  also  well  adapted  for  the  purpose  of  sound- 
production,  and  in  a  few  species  of  the  genus  there  are  al.-» 
highly-developed  stridulating  surfaces  on  the  hind  and  middle 
coxae.  This  is  the  only  case  in  which  a  beetle  is  known  to 
possess  more  than  one  set  of  sound-organs  in  the  imago  state. 
Three  divisions  of  this  family  are  distinguished,  viz.— 

1.  Front  coxae  large  and  transverse  ;  prothorax   with  distinct   side   mar- 
gins. Sub-fain.    1.   PRIONIDES. 

2.  Front  coxae  not  greatly  extended  transversely,  thorax  not  margined  ; 
last  joint  of  maxillary  palpus  not  pointed,  usually  broader  (more  or  less) 
than  the  preceding  joint.  Sub-fain.   2.   CERAMBYCIDK-. 

3.  Front  coxae  usually  round  and  deeply  embedded  ;  last  joint  of  maxil- 
lary palpus  pointed  ;  front  tibiae  with  a  more  or  less  distinct,  slanting  groove 
"ii  the  inner  side.  Sub-fam.   3.   LAMIIDES. 

The  Prionides  are  on  the  average  considerably  larger  in  size 
than  the  members  of  the  other  divisions,  and  they  include  some  of 
the  largest  of  Insects.  The  Amazonian  Titanus  giganteus  and  the 
Fijian  Mn<'r<itn,na  heros  are  amongst  the  most  gigantic.  Some 
uf  the  Prionides  have  a  great  development  of  the  mandibles  in 
the  male  sex  analogous  to  that  we  have  already  noticed  in 
Lucanidae.  The  larvae  of  the  large  Prionides  appear  in  various 
parts  of  the  world  to  have  been  a  favourite  food  with  native 
1  Berlin,  ent.  Zeitsclo:  xli.  1S96,  SB.  p.  22. 


288  COLEOPTERA 


CHAP. 


tribes,  and  Lumholz  states  that  they  are  really  good  eating. 
In  consequence  of  the  destruction  of  forests  that  has  progressed 
so  largely  of  late  years  these  gigantic  Prionides  have  become 
much  rarer. 

Several  aberrant  forms  are  included  in  Prionides.  The  genus 
Parandra  has  five-jointed  tarsi;  the  third  joint  being  much  smaller 
than  usual,  so  that  the  fourth  joint  is  not  concealed  by  it. 
The  Brazilian  Hypocephalus  armatus  was  for  long  a  subject  of 
dispute  as  to  its  natural  position,  and  was  placed  by  different 
authorities  in  widely -separated  families  of  Coleoptera.  The 
structure  of  this  aberrant  Longicorn  seems  to  be  only  explicable 
on  the  hypothesis  of  warfare  amongst  the  males.1  Nothing  is, 
however,  known  as  to  the  habits  and  history  of  the  Insect,  and 
only  one  or  two  specimens  of  the  female  have  yet  been  obtained. 

The  family  Spondylidae  has  been  proposed  for  some  of 
these  aberrant  Longicorns,  but  as  it  includes  but  very  few,  and 
highly  discrepant,  species,  it  is  neither  natural  nor  of  much  use 
for  systematic  purposes. 

The  Lamiides  are  the  most  highly  specialised  division  of  the 
Longicorns,  and  includes  the  larger  number  of  the  species.  The 
front  of  the  head  is  usually  placed  at  right  angles  to  the  vertex, 
and  in  some  cases  (groups  Hippopsini,  Spalacopsini)  it  is  strongly 
intiexed,  so  that  the  mouth  is  placed  on  the  under  side  of  the 
head.  The  extension  of  the  eyes  round  the  antennae  is  accom- 
panied by  very  curious  shapes  of  those  organs,  and  not 
infrequently  each  eye  is  divided  into  two  more  or  less  widely- 
separated  parts,  so  that  the  Insect  has,  on  the  external  surface, 
four  eyes. 

Series  VI.   Rhynchophora. 

Head  more  or  less  prolonged  in  front  to  form  a  snout  or  leal',  called 
rostrum.  Tarsi  four-jointed,  usually  nt  least  tlie  f/iirtl 
joint  Iroad  and  densely  pubescent  leneatJi. 

This  enormous  series  includes  about  25,000  species,  and  as 
may  well  be  imagined  shows  a  great  variety  of  structure  amongst 
its  forms.  The  vast  majority  may,  however,  be  readily  recognised 
by  the  two  characters  mentioned  above.  There  are  some  cases  in 
which  the  beak  is  indistinct,  and  others  in  which  the  tarsi  are 

1  Sharp,  Ann.  Soc.  ent.  Belyique,  xxviii.  1384,  CR.  p.  cvii. 


RHYNCHOPHORA 


289 


five-jointed  (Dryophthorus),  and  even  slender  (Platypides).      In 

these  cases  a  close  examination   shows  that   the  gular  region  on 

the  middle  of  the  back  of  the   under  surface  of  the  head  cannot 

he  detected,  and  that  the  back  of  the  prosternum  is  very  strongly 

consolidated  by  the  side-pieces  of  the  thorax  meeting  together 

and  being  very  firmly  joined  behind  the  coxae.      The  beak  is  in 

the  great  majority  perfectly  distinct,  though  it  varies  so  extremely 

in  form  that  it  can  only  be  briefly  described  by  saying  that  it  is 

a   prolongation   of  the   head   in   front   of  the   eyes,  or  that  the 

antennae  are  inserted  on   its  sides  near  to,  or  far  from,  the  tip. 

It  has  been  ascertained  in  many  cases  that   the  rostrum  is  used 

by  the  female  to  assist   in  placing  the  eggs  in  suitable  places,  a 

hole  being  bored  with  it ;  in  some 

cases  it  is  also  used  to  push  the 

egg  far  into  the  hole  in  which  it 

has    previously    been    placed    by 

the    ovipositor ;    but     there    are 

many  forms  in  which  it  is  fairly 

certain   that    it    is    not    so    used. 

What   purpose   it   serves  in  tbe 

male    is    totally    unknown.       In 

many  members  of  the  series,  the 

rostrum    differs    in   form    in    the 

two  sexes,  and  in  most,  if  not  in 

all,  these  cases  it  is  clear  that  the 

distinctions  tend  in  the  direction 

of  making  the  beak  of  the  female 

more  efficient  for  the  mechanical 

purpose  we  have  mentioned. 

It  was  proposed  by  Leconte 
and  Horn  to  separate  this  series 
from  all  the  other  Coleoptera  as 
a  primary  division,  and  they 
looked  on  it  as  of  lower  or  more 
imperfect  structure.  Packard  has 
very  properly  protested  against  FIG.  Itf.—Evgnoristws  mu-uachus  ?. 

, -L  •        •  ,  .  Madagascar.     A.  The  imago ;  B,  front 

this    interpretation  ;     and    there        of  pr0notum,  head,  and  rostrum, 
seems  to  be  no   reason  whatever 

for  considering  the  Khynchophora  as  "  lower  "  than  other  beetles  ; 
indeed  we  should  be  inclined  to  place  such  forms  as  Calandrides 
VOL.  VI  u 


290  COLEOPTERA  CHAP. 

amongst  the  most  perfect  of  Insects  ;  their  external  structure  (as 
shown  by  Eugnoristus  monachus,  Fig.  147)  being  truly  admirable. 
Only  four  families  of  Ehynchophora  can  lie  at  present 
accepted  as  satisfactory  ;  one  of  these  —  Curculionidae  —  includes 
an  enormous  majority  of  the  whole  series.  Though  it  is  probable 
that  it  will  ultimately  be  divided  into  several  families,  the 
attempts  to  that  end  that  have  already  been  made  are  not 
satisfactory. 

Fam.  80.  Anthribidae.  —  Palpi  usually  not  covered,  Imt  dis- 
tinct and  flexible.  Antennae  often  long,  not  elbowed,  the  first  joint 
n«t  r<  r;i  lonij.  Third  joint  of  tarsus  small,  usually  much  concealed 
by  being  embraced  by  the  second  joint.  Pi/gidii/ni  exposed;  pro- 
/if/i/idu/tn.  deeply  grooved  in  the  midJfr.  This  family  includes  800 
or  more  species,  which  are  mostly  tropical  ;  it  is  very  sparsely 
represented  in  the  faunas  of  Europe  and  North  America.  It  is 
quite  distinct  from  Curculionidae  with  which  it  was  formerly 
associated.  It  contains  many  graceful  Insects  having  a  certain 
resemblance  with  Longicorns  on  account  of  the  large  development 

of  the  antennae.  The  habits  and  meta- 
morphoses are  but  little  known.  It 
seems  probable  that  many  species  find 
their  nutriment  in  old  wood  or  boleti. 
The  larvae  of  some  genera  (Cratoparis 
and  Araeocerus)  have  legs,  but  in  others 
the  legs  are  wanting,  and  the  larvae  are 
said  to  completely  resemble  those  of 
Curculionidae.  In  the  larva  of  our 
tiny  British  species,  Choragus  sheppardi, 
the  legs  are  replaced  by  three  pairs 
of  thoracic,  sac-like  pseudopods.  This 
Insect  makes  burrows  in  dead  branches 
FIG.  i48.--P/r^/,v,/,,,|.<  lati-  of  iiawth0m.  The  larvae  of  the  genus 

/•'.N//-/.V,  Anthribidae.   Britain.  _     ° 

A,  the  perfect  insect  ;   B,   Bi'achytarsus    have   been    ascertained    to 

tarsus  and  tip  o  prey  Qn   Cocddae_ 

Fam.  81.  Curculionidae  (  Wecrils).  —  The  beak  of  rery  variable 


and    t/iir/,-/irss  ;    the  palpi-   small,  nearly    always   concealed 
within   Hie  mouth,  short,  and  rigid.      Labr/n/i    absent.      Antennae 
of  the    majority   r/bu/red,  i.e.  with    the  basal  joint  longer,  and  so 
formed  that  when  'it  is  faff  rally  extruded  the  other  joints  can  be 
placed  in  a  forward  direction.      This  enormous  family  includes 


v  RHYNCHOPHORA CURCULIONIDAE  291 

about  20,000  known  species,  and  yet  a  large  portion  of  the 
species  yearly  brought  from  the  tropics  still  prove  to  be  new. 
The  rostrum  or  beak  exhibits  excessive  variety  in  form,  and  is  in 
many  cases  different  in  the  sexes  ;  in  this  case  it  is  usually  longer 
and  thinner  in  the  female.  As  the  rostrum  is  one  of  the  chief 
characters  by  which  a  member  of  the  family  may  be  recognised, 
it  is  necessary  to  inform  the  student  that  in  certain  forms  (the 
Australian  Amycterid.es,  e.g.')  the  organ  in  question  may  be  so 
short  and  thick  that  it  is  almost  absent.  In  these  cases  the 
Insect  may  be  identified  as  a  Curculionid  by  the  gular  area  being 
absent  on  the  under  side  of  the  head,  and  by  the  concealment  of 
the  palpi.  The  tarsi  are  usually  of  the  same  nature  as  those  of 
Phytophaga,  already  described,  but  the  true  fourth  joint  is  less 
visible.  In  the  Brachycerides  this  joint  is  not  present,  and  the 
third  joint  is  not  lobed.  The  palpi  are  flexible  and  more  or 
less  exserted  in  a  very  few  species  (Rhynchitides) ;  in  Rhinoma- 
cerides  there  is  also  present  a  minute  labrum.  The  front  coxae 
are  deeply  embedded,  and  in  many  forms  the  prosternum  is 
peculiar  in  structure ;  the  side-pieces  (epimera)  meeting  at  the 
back  of  the  prosternum  in  the  middle  line.  This,  however,  is 
not  universal  in  the  family,  and  it  occurs  in  some  other  beetles 
(e.g.,  Megalopodides  of  the  Phytophaga).  The  larvae  are  without 
legs.  They  are  vegetarian,  the  eggs  being  deposited  by  the 
mother-beetle  in  the  midst  of  the  food.  These  larvae  may  be 
distinguished  from  those  of  Longicorns  by  the  general  form, 
which  is  sub-cylindric  or  rather  convex,  not  flattened,  and 
more  particularly  by  the  free,  exserted  head,  the  mouth  being 
directed  downwards ;  the  attitude  is  generally  a  curve,  and  the 
anterior  part  of  the  body  is  a  little  the  thicker.  Xo  part  of 
plants  is  exempt  from  the  attacks  of  the  larvae  of  Curculionidae ; 
buds,  twigs,  leaves,  flowers,  fruits,  bark,  pith,  roots  and  galls 
may  each  be  the  special  food  of  some  Curculionid.  Certain 
species  of  the  sub-families  Rhynchitides  and  Attelabides  prepare 
leaves  in  an  elaborate  manner  to  serve  as  food  and  dwelling  for 
their  young.  If  young  birches,  or  birch  bushes  from  5  to  10 
feet  in  height,  be  looked  at  in  the  summer,  one  may  often  notice 
that  some  of  the  leaves  are  rolled  so  as  to  form,  each  one,  a  little 
funnel.  This  is  the  work  of  Ehynchites  (or  Deporaus)  betulae,  a 
little  Curculionid  beetle  (Fig.  149).  An  inspection  of  one  of 
these  funnels  will  show  that  it  is  very  skilfully  constructed.  The 


292 


COLEOPTERA 


CHAP. 


whole  of  a  leaf  is  not  used  in  the  formation  of  a  funnel,  cuts  being 
made  across  the  leaf  in  suitable  directions.  The  beetle  stand- 
ing on  a  leaf,  as  shown  in  the  figure,  proceeds  to  cut  with  its 
mandibles  an.  incision  shaped  like  an  erect  S,  commencing  at  a 
certain  part  of  the  circumference,  and  ending  at  the  midrib  of  the 
leaf;  the  beetle  then  goes  to  the  other  side  of  the  midrib,  and 
continues  its  incision  so  as  to  form  another  S-like  curve  con- 
siderably different  from  the  first ;  being  prostrate  and  less  abrupt. 
Thus  the  blade  of  the  leaf  is  divided  into  two  halves  by  certain 
curved  incisions,  the  midrib  remaining  intact.  The  little  funuel- 


FIG.  149. — The  leaf-rolling  of  Rh yncli  itf*  l^ti/hic.  Britain.  A,  Female  beetle,  magnified  : 
B,  the  beetle  forming  the  first  incision  on  a  leaf  ;  C.  the  completed  roll.  (B  and  C 
after  Debey. ) 

twister  no\v  commences  to  roll  up  the  leaf  to  form  the  funnel ; 
and  this  part  of  the  work  is  greatly  facilitated  by  the  shape  of 
the  incisions.  Going  back  to  the  spot  where  it  commenced  work, 
by  the  aid  of  its  legs  it  rolls  one  side  of  the  leaf  round  an  ideal 
axis,  somewhat  on  the  same  plan  as  that  adopted  by  a  grocer  in  form- 
ing a  paper-funnel  for  sugar.  The  incisions  are  found  to  be  just 
of  the  right  shape  to  make  the  overlaps  in  the  rolling,  and  to  re- 
tain them  rolled-up  with  the  least  tendency  to  spring  back.  After 
some  other  operations  destined  to  facilitate  subsequent  parts  of  its 
task,  the  beetle  enters  the  rolled-up  part  of  the  leaf  and  brings  it 
more  perfectly  together;  it  again  comes  out  and,  pursuing  a 
different  system,  holds  on  with  the  legs  of  one  side  of  the  body 


v  RHYNCHOPHORA — CURCULIONIDAE  293 

to  the  roll,  and  with  the  other  legs  drags  to  it  the  portion  of  the 
leaf  on  the  other  side  of  the  midrib  so  as  to  wrap  this  part  (i.e. 
the  result  of  its  second  incision)  round  the  part  of  the  funnel 
already  constructed.  This  being  done  the  Insect  again  enters 
the  funnel,  bites  three  or  four  small  cavities  on  the  inside  of  the 
leafy  wall  and  deposits  an  egg  in  each.  Afterwards  it  emerges 
and  fits  the  overlaps  together  in  a  more  perfect  manner  so  as  to 
somewhat  contract  the  funnel  and  make  it  firmer  ;  then  proceeding 
to  the  tip,  this  is  operated  on  by  another  series  of  engineering 
processes  and  made  to  close  the  orifice ;  this  part  of  the  opera- 
tion being  analogous  to  the  closing  by  the  grocer  of  his  paper- 
funnel  after  the  sugar  has  been  put  in.  The  operation  of  the 
beetle  is,  however,  much  more  complex,  for  it  actually  makes  a 
sort  of  second  small  funnel  of  the  tip  of  the  leaf,  bends  this  in,  and 
retains  it  by  tucking  in  some  little  projections.  The  work,  which 
has  probably  lasted  about  an  hour,  being  now  completed,  the  creature 
takes  a  longer  or  shorter  rest  before  commencing  another  funnel. 
We  have  given  only  a  sketch  of  the  chief  points  of  the  work, 
omitting  reference  to  smaller  artifices  of  the  craft  master ;  but 
we  may  remark  that  the  curved  incisions  made  by  the  beetle 
have  been  examined  by  mathematicians  and  duly  extolled  as 
being  conducted  on  highly  satisfactory  mathematical  principles. 
It  is  impossible  at  present  for  us  to  form  any  conception  as  to  the 
beetle's  conceptions  in  carrying  out  this  complex  set  of  operations. 
Our  perplexity  is  increased  if  we  recollect  its  life-history,  for  we 
then  see  that  neither  precept  or  example  can  have  initiated  its 
proceedings,  and  that  imitation  is  out  of  the  question.  The  eggs 
hatch  in  their  dark  place,  giving  rise  to  an  eyeless  maggot, 
which  ultimately  leaves  the  funnel  for  the  earth.  The  parts  of 
this  maggot  subsequently  undergo  complete  change  to  produce 
the  motionless  pupa  of  entirely  different  form,  from  which 
emerges  the  perfect  Insect.  Hence  the  beetle  cannot  be  con- 
sidered to  have  ever  seen  a  funnel,  and  certainly  has  never 
witnessed  the  construction  of  one,  though,  when  disclosed,  it 
almost  immediately  sets  to  work  to  make  funnels  on  the  complex 
and  perfect  system  we  have  so  imperfectly  described.  More 
general  considerations  only  add  to  the  perplexity  we  must  feel 
when  reflecting  on  this  subject.  Why  does  the  Insect  construct 
the  funnel  at  all  ?  As  a  matter  of  protection  it.  appears  to  be 
of  little  use,  for  the  larvae  are  known  to  suffer  from  the  attacks 


294  COLEOPTERA  CHAP. 

of  parasites  as  other  Insects  do.  We  have  not  the  least  reason 
for  supposing  that  this  mode  of  life  for  a  larva  is,  so  far  as 
utility  is  concerned,  better  than  a  more  simple  and  usual  one. 
Indeed,  extraordinary  as  this  may  appear,  it  is  well  known  that 
other  species  of  the  same  genus  adopt  a  simple  mode  of  life, 
laying  their  eggs  in  young  fruits  or  buds.  We  think  it  possible, 
however,  that  a  knowledge  of  the  mode  of  feeding  of  this  larva 
may  show  that  a  more  perfect  nutrition  is  obtained  from  a  well- 
constructed  cylinder,  and  if  so  this  would  to  a  slight  extent 
satisfy  our  longing  for  explanation,  though  throwing  no  light 
whatever  on  the  physiology  or  psychology  of  the  artificer,  and 
leaving  us  hopelessly  perplexed  as  to  why  a  beetle  in  ages  long 
gone  by  should  or  could  adopt  a  mode  of  life  that  by  long  pro- 
cesses of  evolution  should,  after  enormous  difficulties  have  been 
overcome,  attain  the  perfection  we  admire.1 

Fam.  82.  Scolytidae. — Rostrum  extremely  short,  broad ;  tibiae 
frequently  denticulate  externally;  antennae,  short,  with  a  Iroad 
cluli.  This  family  is  not  at  all  sharply  distinguished  from  certain 
groups  of  Curculionidae  (from  Cossonid.es  e.g.},  but  as  the  species 
have  somewhat  different  habits,  and  in  the  majority  of  cases 
can  be  readily  distinguished,  it  is  an  advantage  to  separate 
the  two  families.  About  1400  species  are  at  present  known. 
Most  of  them  are  wood-  and  bark-feeders;  some  bore  into  hard 
wood ;  a  few  mine  in  twigs  or  small  branches  of  trees,  but  the 
majority  live  in  the  inner  layers  of  the  bark ;  and  this  also 
serves  as  the  nidus  of  the  larvae.  A  small  number  of  species 
have  been  found  to  inhabit  the  stems  of  herbaceous  plants,  or  to 
live  in  dry  fruits.  Owing  to  their  retiring  habits  they  are  rarely 
seen  except  by  those  who  seek  .them  in  their  abodes,  when  they 
may  often  be  found  in  great  profusion.  The  mother-beetle  bores 
into  the  suitable  layer  of  the  bark,  forming  a  sort  of  tunnel  and 
depositing  eggs  therein.  The  young  larvae  start  each  one  a 
tunnel  of  its  own,  diverging  from  the  parent  tunnel ;  hence  each 
batch  of  larvae  produces  a  system  of  tunnels,  starting  from  the 
parents'  burrow,  and  in  many  species  these  burrows  are  charac- 

1  For  a  Tnore  extensive  account  of  Rhynchites  bctuJae  and  others  refer  to 
Wasmann.  Dcr  Trickier  wickler,  Minister,  1884,  and  Debey,  Beitrdgc  zur  Lebcus- 
und  Entwickelungs-geschichte  .  .  .  <l?r  AUcl«l>uJ?n,  Bonn,  184(5.  The  first  in- 
cludes an  extensive  philosophical  discussion  ;  the  second  is  a  valuable  collection 
of  observation-. 


v  KHYNCHOPHORA SCOLYTIDAE — BRENTHIDAE          295 

teristic  in  form  and  direction,  so  that  the  work  of  particular 
Scolytids  can  be  recognised  by  the  initiated. 

The  Platypides  bore  into  the  wood  of  trees  and  stumps ;  they 
are  chiefly  exotic,  and  little  is  known  about  them.  They  are 
the  most  aberrant  of  all  Rhynchophora,  the  head  being  remarkably 
short,  flat  in  front,  with  the  mouth  placed  on  the  under  surface 
of  the  head,  there  being  no  trace  of  a  rostrum :  the  tarsi  are 
elongate  and  slender,  the  third  joint  not  being  at  all  lobed,  while 
the  true  fourth  joint  is  visible.  Hence  they  have  not  the 
appearance  of  Rhynchophora.  Some  authorities  treat  the 
Platypides  as  a  distinct  family. 

Some  of  the  members  of  the  group  Tomicides  also  bore  into 
the  wood.  Recent  observations  have  shown  that  there  is  an 
important  feature  in  the  economy  of  certain  of  these  wood- 
borers,  inasmuch  as  they  live  gregariously  in  the  burrow,  and 
feed  on  peculiar  fungi  that  develop  there,  and  are  called  ambrosia. 
According  to  Hubbard,1  some  species  cultivate  these  fungi, 
making  elaborate  preparations  to  start  their  growth.  The  fungi, 
however,  sometimes  increase  to  such  an  extent  as  to  seal  up  the 
burrows,  and  kill  the  Insects  by  suffocation. 

Scolytidae  sometimes  multiply  to  an  enormous  extent,  attack- 
ing and  destroying  the  trees  in  wooded  regions.  Much  dis- 
cussion has  taken  place  as  to  whether  or  not  they  are  really 
injurious.  It  is  contended  by  one  set  of  partisans  that  they 
attack  only  timber  that  is  in  an  unhealthy,  dying,  or  dead  con- 
dition. It  may  be  admitted  that  this  is  usually  the  case  ;  yet 
when  they  occur  in  enormous  numbers  they  may  attack  timber 
that  is  in  a  sort  of  neutral  state  of  health,  and  so  diminish  its 
vigour,  and  finally  cause  its  destruction.  Hence  it  is  of  great 
importance  that  they  should  be  watched  by  competent  foresters. 

The  larvae  of  Scolytidae  are  said  to  completely  resemble  those 
of  Curculionidae  :  except  in  the  group  Platypides,  where  the  body 
is  straight  and  almost  cylindrical,  and  terminates  in  an  oblique 
truncation  bearing  a  short  hard  spine.2 

Fam.  83.  Brenthidae. — Form  elongate;  rostrum  straight, 
ili/'cctly  continuing  the  long  axis  of  the  body,  often  so  thick  as  to 
form  an  elongate  head ;  antennae  not  elbou-ed.  The  Brenthidae 
form  a  family  of  about  800  species,  remarkable  for  the  excessive 

1  Bull.  U.S.  Dcp.  Agric.  ent.     New  series,  No.  7,  1897. 
2  Penis,  Ann.  Sci.  Nat.  (2)  xiv.  1840.  p.  89,  pi.  iii. 


296 


COLEOPTERA 


length    and    sleuderness    of    some    of    its    forms,    and    for    the 


s 


extreme   difference   in   the   sexes   that  frequently  exists.      It 

well  represented  in  the  tropics 
only,  and  very  little  is  known 
as  to  the  natural  history  and 
development.  These  beetles  are 
stated  to  lie  wood-feeders,  and 
no  doubt  this  is  correct  in  the 
case  of  the  majority  of  the 
species  ;  but  Mr.  Lewis  observed 
in  Japan  that  Zemioses  celtis  and 
Cyphagogus  segnipes  are  pre- 
d;iceous,  and  enter  the  burrows 

of  wood-boring  Insects  to  search 
fiG.     150.  —  JSupsalis     mmuta.       Aorth 

America.     A,    Larva  ;   B.  pupa  ;    c,    for    larvae    as    prey  :     they    are 

female  imago;  D,  head  of  male.    (After    veiy  much  modified  ill  Structure 

to  permit  this  ;  and  as  the  other 

members  of  the  group  Taphroderides  are  similar  in  structure, 
it  is  probable  that  they  are  all  predaceous.  Nothing  what- 
ever is  known  as  to  the  larval  history  of  these  carnivorous 
forms.  Indeed  an  uncertainty,  almost  complete,  prevails  as  to 
the  early  stages  of  this  family.  Eiley  has  given  a  sketch  of  a 
larva  which  he  had  no  doubt  was  that  of  .#///>  W/.s  minuta,  the 
North  American  representative  of  the  family  ;  if  he  is  correct 
the  larva  differs  from  those  of  Curculionidae  by  its  elongate  form, 
and  by  the  possession-  of  thoracic  legs  :  these,  though  small,  are 
three-jointed.  Descriptions,  supposed  to  be  those  of  Brenthid 
larvae,  were  formerly  published  by  Harris  and  Motschoulsky  ; 
but  it  is  now  clear  that  both  were  mistaken. 

In  the  higher  forms  of  Brenthidae  the  rostrum  of  the  female 
is  perfectly  cylindrical  and  polished,  and  the  mandibles  are 
minute,  hard,  pointed  processes  placed  at  its  tip.  This  organ  is 
admirably  adapted  to  its  purpose  ;  it  being  used  for  boring  a  hole 
in  wood  or  bark,  in  which  ;in  egg  is  subsequently  deposited.  The 
males  in  these  cases  are  extremely  different,  so  that  considerable 
curiosity  is  felt  as  to  why  this  should  be  so.  In  some  cases  their 
head  is  thick,  and  there  may  be  no  rostrum,  while  large  powerful 
mandibles  are  present. 

In  other  cases  the  rostrum  is  slender,  but  of  enormous 
length,  so  that  it  may  surpass  in  this  respect  the  rest  of 


v  BRENTHIDAE AGLYCYDERIDAE  297 

the  body,  although  this  itself  is  so  drawn  out  as  to  be  quite 
exceptional  in  the  Insect  world : l  the  antennae  are  inserted 
near  the  tip  of  the  rostrum  instead  of  near  its  base,  as  they 
are  in  the  female.  The  size  of  the  males  is  in  these  cases  usually 
much  larger  than  that  of  the  female.'2  The  males  of  some  species 
tight ;  they  do  not,  however,  wound  their  opponent,  but  merely 
frighten  him  away.  In  Eupscdis  it  appears  that  the  rostrum 
of  the  female  is  apt  to  become  fixed  in  the  wood  during  her 
boring  operations  ;  and  the  male  then  extricates  her  by  pressing 
his  heavy  prosternum  against  the  tip  of  her  abdomen  ;  the  stout 
forelegs  of  the  female  serve  as  a  fulcrum  and  her  long  body  as  a 
lever,  so  that  the  effort  of  the  male,  exerted  at  one  extremity  of 
the  body  of  the  female,  produces  the  required  result  at  the  other 
end  of  her  body.  The  New  Zealand  Brenthid,  Lasiorhynchus 
barlini/'iiis,  exhibits  sexual  disparity  in  an  extreme  degree:  the 
length  of  the  male  is  usually  nearly  twice  that  of  the  female,  and 
his  rostrum  is  enormous.  It  is  at  present  impossible  to  assign 
any  reason  for  this ;  observations  made  at  the  request  of  the 
writer  by  Mr.  Helms  some  years  ago,  elicited  the  information 
that  the  female  is  indefatigable  in  her  boring  efforts,  and  that 
the  huge  male  stands  near  by  as  a  witness,  apparently  of  the 
most  apathetic  kind. 


Coleoptera  of  uncertain  position. 

There  are  three  small  groups  that  it  is  impossible  at  present 
to  place  in  any  of  the  great  series  of  beetles. 

Fam.  84.  Aglycyderidae.  -  -  Tarsi  three-jointed,  the  second 
joint  lobed ;  head  not  prolonged,  to  form  a  beak.  The  two  most 
important  features  of  Rhynchophora  are  absent  in  these  Insects, 
while  the  other  structural  characters  are  very  imperfectly  known, 
many  parts  of  the  external  skeleton  being  so  completely  fused 
that  the  details  of  structure  are  difficult  of  appreciation.  AVest- 
wood  considered  the  tarsi  to  be  really  four-jointed,  but  it  is  not 

1  In  the  males  of  the  genus  Cedeocera  the  tips  of  the  elytra  are  drawn  out  into 
processes  almost  as  long  as  the  elytra  themselves,  and  rivalling  the  forceps  of 
earwigs. 

'•  The  stature  of  the  individuals  of  the  same  species  is,  in  some  of  these 
Brenthidae,  subject  to  extreme  variation,  especially  in  the  males,  some  individuals 
of  which — in  the  case  of  Brcntltus  anchorage* — are  five  times  as  long  as  others. 


298 


COLEOPTERA 


CHAP. 


at  all  clear  that  the  minute  knot  he  considered  the  third  joint  is 

more  than  the  articulation 
of  the  elongate  terminal 
joint.  The  family  consists 
only  of  two  or  three  species 
of  Aglycyderes,  one  of  which 
occurs  in  the  Canary 
Islands,  and  one  or  two  in 
New  Zealand  and  Xew 
Caledonia.  The  former  is 
believed  to  live  in  the  stems 
of  Euphorbia  canariensis  ; 
Canary  islands,  a  Xew  Zealand  species  has 

_          ITT  1  •*• 


151.  —  A'jtiic,/<i,<,Yx 


A,  Imago  ;  B,  tarsus  according  to  Westwood  ; 


C,     according    to    nature  ; 
labium. 


been    found    in   connection 


D,     maxilla  ;    E, 

with  the  tree-fern  Cyathea 
dealbata. 

Fam.  85.  Proterhinidae. — Tarsi  three-jointed,  the  second  joint 
lol>ed ;  head  of  the  male  scarcely  prolonged,  hut  that  of  the  female 
fur ming  a  definite  rostrum.;  maxillae  and  ligula  entirely  covered 
l>y  the  mention-.  As  in  the  preced- 
ing family  the  sutures  on  the 
under  side  of  the  head  and  pro- 
sternum  cannot  be  detected.  The 
minute  palpi  are  entirely  enclosed 
in  the  buccal  cavity.  There  is  a 
very  minute  true  third  joint  of 
the  tarsus,  at  the  base  of  the  ter- 
minal joint,  concealed  between  the 
lobes  of  the  second  joint.  The 
family  consists  of  the  genus  Pro- 
terhinus  ;  it  is  confined  to 
Hawaiian  Islands,  where  these  In- 
sects live  on  dead  wood  in  the 
native  forests.  The  genus  is  numerous  in  species  and  individuals. 

Strepsiptera  (or  Rhipiptera,  Stylopidae).--Jfa£e  small  or 
minute;  prothorax  extremely  small ;  mesothorax  moderate,  the  elytra 
reduced  to  small,  free  slips;  metathorax  and  wings  very  large; 
nervuration  of  the  latter  radiating.  •n-Hliunt  cross  nervules.  female 
a  mere  sac,  with  one  extremity  smaller  and  forming  a  sort  of  neck 
or  head.  These  curious  Insects  are  parasitic  in  the  interior  of 


the  Fio.  152. — 1'i-iifi'rliiiinx  /eciiiifei.  Ha- 
waiian Islands.  A,  Male  ;  B,  female  ; 
C,  front  foot,  more  magnified. 


STREPSIPTERA 


299 


other  Insects,  of  the  Orders  Hymenoptera  and  Hemiptera.  Their 
structure  and  their  life-histories  entitle  them  to  be  ranked  as 
the  most  abnormal  of  all  Insects,  and  entomologists  are  not 
agreed  as  to  whether  they  are  aberrant  Coleoptera  or  a  distinct 
Order.  The  newly-hatched  larva  is  a  minute  triungulin  (Fig. 
154),  somewhat  like  that  of  Meloe;  it  fixes  itself  to  the  skin 
of  the  larva  of  a  Hymenopterous  Insect,  penetrates  into  the 
interior,  and  there  undergoes  its  metamorphoses,  the  male  emerg- 
ing to  enjoy  a  brief  period  of  an  abnormally  active,  indeed  agitated, 
existence,  while  the  female  never  moves.  It  is  important  to 
note  that  these  Strepsiptera  do  not,  like  most  other  internal 
parasites,  produce  the  death  of  their  hosts  ;  these  complete  their 
metamorphosis,  and  the  development  of  the  parasite  goes  on 
simultaneously  with  that  of  the  host,  so  that  the  imago  of  the 


FIG.  153. — Sexes  of  Strep- 
siptera. A,  Male  of 
Stylops  dalii  (after  Cur- 
tis) ;  B,  female  of  Xenos 
rossii  (after  von  Siebold). 


B 


A 


Strepsipteron  is  found  only  in  the  imago  of  the  host.1  After 
the  young  Stylops  has  entered  its  host  it  feeds  for  a  week  or  so 
on  the  fat-body  (apparently  by  a  process  of  suction),  then 
moults  and  assumes  the  condition  of  a  footless  maggot,  in  which 
state  it  remains  till  growth  is  completed.  At  the  latter  part  of 
this  period  the  history  diverges  according  to  sex  ;  the  female 
undergoes  only  a  slight  metamorphic  development  of  certain 
parts,  accompanied  apparently  by  actual  degradation  of  other 
parts  ;  while  the  male  goes  on  to  pupation,  as  is  normal  in  Insects. 
(We  may  remark  that  the  great  features  of  the  development  of 
the  sexes  are  parallel  with  those  of  Coccidae  in  Hemiptera.) 
AVhen  the  Hymenopterous  larva  changes  to  a  pupa,  the  larva 
of  the  Strepsipteron  pushes  one  extremity  of  its  body  between  two 
of  the  abdominal  rings  of  its  host,  so  that  this  extremity  becomes 
external,  and  in  this  position  it  completes  its  metamorphosis,  the 

1  This  remark  applies  to  the  Strepsiptera  parasitic  on  Hymenoptera  :  nothing 
whatever  is  known  as  to  the  life-histories  of  the  species  that  attack  Hemiptera. 


;oo 


STREPSIPTERA 


CHAP. 


male  emerging  very  soon  after  the  host  has  become  an  active 
winged  Insect,  while  the  female  undergoes  no  further  change  of 
position,  but  becomes  a  sac,  in  the  interior  of  which  young 
develop  in  enormous  numbers,  finally  emerging  from  the  mother- 
sac  in  the  form  of  the  little  triungulins  we  have  already 
mentioned.  This  is  all  that  can  be  given  at  present  as  a  general 
account ;  many  points  of  the  natural  history  are  still  obscure, 
others  have  been  merely  guessed ;  while  some  appear  to  differ 

greatly  in   the   different   forms.      A  few  brief 
remarks  as  to  these  points  must  suffice. 

Bees  carrying,  or  that  have  carried,  Strep- 
siptera,  are  said  to  be  stylopised  (it  being  a 
species  of  the  genus  Xtylops  that  chiefly  infests 
bees) ;  the  term  is  also  used  with  a  wider 
application,  all  Insects  that  carry  a  Strepsip- 
terous  parasite  being  termed  stylopised,  though 
it  may  be  a  Strepsipteron  of  a  genus  ATery 
different  from  ^////n/is  that  attacks  them.  The 
development  of  one  or  more  Strepsiptera  in 
an  Insect  usually  causes  some  deformity  in 
the  abdomen  of  its  host,  and  effects  consider- 
able changes  in  the  condition  of  its  internal 
organs,  and  also  in  some  of  the  external  char- 
acters. Great  difference  of  opinion  prevails 
as  to  what  these  changes  are ;  it  is  clear,  how- 
FIG.  154.—  Young  larva  ever,  that  they  vary  much  according  to  the 

of  Stulops  on  a  Lee's-  -11  T  <? 

hair.   Greatly  magni-   species,  and  also   according   to   the   extent   of 

lied.  (After Newport.)   the   stylopisatioii.      Usually   only  one  Stylops 

is    developed   in   a   bee ;  but   two,   three,   and 

even  four   have   been   observed:1   and   in   the   case   of  the   wasp, 

Polistcs,    Hubbard    has    observed    that   a   single    individual   may 

bear    eight    or    ten    individuals    of     its     Strepsipteron    (Xenos, 

n.  sp.  ?). 

There  is  no  exact  information  as  to  how  the  young  triungulins 
find  their  way  to  the  bee -larvae  they  live  in.  Here  again  the 
discrepancy  of  opinion  that  prevails  is  probably  due  to  great 

1  Although  not  an  invariable,  it  seems  that  it  is  a  general  rule  that  the  Stylops 

produced    from   the  body  of  one   individual   are  all  of  one  sex  ;  it  has  even  been 

bated   that    female  bees    produce    moiv   especially  female  Stylops.   and   male   bees 

male  kstylupK.      If  any  correlation  as  to  this  latter  point  exist,  it  is  far  from  general. 


STYLOPS 


301 


difference  really  existing  as  to  the  method.  When  a  Stylops 
carried  by  an  Insect  (a  Hymenopteron,  be  it  noted,  for  we  have 
no  information  whatever  as  to  Hemiptera)  produces  young, 
they  cover  the  body  of  the  host  as  if  it  were  powdered,  being 
excessively  minute  and  their  numbers  very  great ;  many  hundreds, 
if  not  thousands,  of  young  being  produced  by  a  single  Stylops. 
The  species  of  the  wasp  genus  Polistes  are  specially  subject  to 
the  attacks  of  Stylops  ;  they  are  social  Insects,  and  a  stylopised 
specimen  being  sickly  does  not  as  a  rule  leave  the  nest ;  in  this 
case  the  Stylops  larva  may  therefore  have  but  little  difficulty  in 
finding  its  way  to  a  Hymenopterous  larva,  for  even  though  it 
may  have  to  live  for  months  before  it  has  the  chance  of  attaching 
itself  to  a  nest -building  female,  yet  it  is  clearly  in  the  right 
neighbourhood.  The  bee  genus  Andrena  has,  however,  quite 
different  habits ;  normally  a  single  female  makes  her  nest  under- 
ground ;  but  in  the  case  of  a  stylopised  female  it  is  certain  that 
no  nest  is  built,  and  no  larvae  produced  by  a  stylopised  example, 
so  that  the  young  triungulins  must  leave  the  body  of  the  bee  in 
order  to  come  near  their  prey.  They  can  be  active,  and  have 
great  powers  of  leaping,  so  that  it  is  perhaps  in  this  way  possible 
for  them  to  attach  themselves  to  a  healthy  female  bee. 

We  have  still  only  very  imperfect  knowledge  as  to  the  struc- 
ture and  development  of  Strepsip- 
tera.  Indeed  but  little  informa- 
tion has  been  obtained  since 
1S43.1  Before  that  time  the 
mature  female  was  supposed  to  be 
a  larva,  and  the  triungulins  found 
in  it  to  be  parasites.  Although 
the  erroneous  character  of  these  FlQ>  155._porti0n  of  early  stages  of 
views  has  been  made  clear,  the 
problems  that  have  been  sug- 
gested present  great  difficulties. 
Apparently  the  change  from  the 
triungulin  condition  (Fig.  154)  to 
the  parasitic  larvae  (Fig.  1 5  5,  A,  B) 
is  extremely  great  and  abrupt,  and  it  appears  also  that  during 


Xenos  rossii.  (After  YOU  Siebold.) 
A,  Small  male  larva  ;  B,  small  female 
larva  ;  C,  full-grown  male  larva  ;  D, 
full-grown  female  larva  ;  E,  the  so- 
called  "  cephalothorax  "  and  adjacent 
segment  of  adult  female.  (The  newly- 
hatched  larva  is  very  much  like  that 
of  Styloi>s  shown  in  Fig.  154.) 


1  Yon  Siebold,  Arch.  Naturgcs.  ix.  1843,  pp.  137-161.  Xassonoff's  recent  paper 
is  in  Russian,  but  so  far  as  we  can  gather  (cf.  Zool.  Centralbl.  i.  1894,  p.  766),  it  does 
not  add  greatly  to  the  data  furnished  by  von  Siebold. 


3O2  STREPSIPTERA  CHAP. 

the  larval  growth  considerable  sexual  differentiation  occurs  (Fig. 
155,  C,  D) ;  details  are,  however,  wanting,  and  there  exists  but 
little  information  as  to  the  later  stages.  Hence  it  is  scarcely 
a  matter  for  surprise  that  authorities  differ  as  to  which  is  the 
head  and  which  the  anal  extremity  of  the  adult  female.  Yon 
Siebold  apparently  entertained  no  doubt  as  to  the  part  of  the 
female  that  is  extruded  being  the  anterior  extremity  ;  indeed  lie 
called  it  a  cephalothorax.  Supposing  this  view  to  be  correct,  we  are 
met  by  the  extraordinary  facts  that  the  female  extrudes  the  head 
for  copulatory  purposes,  that  the  genital  orifice  is  placed  thereon, 
and  that  the  young  escape  by  it.  Meinert l  contends  that  the 
so-called  cephalothorax  of  the  adult  is  the  anal  extremity,  and 
that  fertilisation  and  the  escape  of  the  young  are  effected  by  the 
natural  passages,  the  anterior  parts  of  the  body  being  affected  by 
a  complete  degeneration.  Nassonoff,  in  controversion  of  Meinert, 
has  recently  pointed  out  that  the  "  cephalothorax  "  of  the  young- 
is  shown  by  the  nervous  system  to  be  the  anterior  extremity.  It' 
still  remains,  however,  to  be  shewn  that  the  "  cephalothorax  "  of 
the  adult  female  corresponds  with  that  of  the  young,  and  we  shall 
not  be  surprised  if  Meinert  prove  to  be  correct.  The  internal 
anatomy  and  the  processes  of  oogenesis  appear  to  be  of  a  very  unusual 
character,  but  their  details  are  far  from  clear.  Brandt  has  given 
some  particulars  as  to  the  nervous  system  ;  though  he  does  not 
say  whether  taken  from  the  male  or  female,  we  may  presume  it  to 
be  from  the  former ;  there  is  a  supra -oesophageal  ganglion,  and 
near  it  a  large  mass  which  consists  of  two  parts,  the  anterior  repre- 
senting the  sub-oesophageal  and  the  first  thoracic  ganglia,  while 
the  posterior  represents  two  of  the  thoracic  and  most  of  the 
abdominal  ganglia  of  other  Insects ;  at  the  posterior  extremity, 
connected  with  the  other  ganglia  by  a  very  long  and  slender 
commissure,  there  is  another  abdominal  ganglion.2 

It  is  a  matter  of  great  difficulty  to  procure  material  for  the 
prosecution  of  this  study ;  the  fact  that  the  instars  to  be  observed 
exist  only  in  the  interior  of  a  few  Hymenopterous  larvae,  which 
in  the  case  of  the  bee,  Andrenu,  are  concealed  under  ground ;  and 
in  the  case  of  the  wasps,  Pulistes,  placed  in  cells  in  a  nest  of 
wasps,  adds  greatly  to  the  difficulty.  It  is  therefore  of  interest 
to  know  that  Strepsiptera  occur  in  Insects  with  incomplete 

1  Ent.  Meddcl.  v.  1890.  j>.  14S,  and  <>c.  Dunske  Selsk.  1896,,  p.  67. 
-'       i-  Soc.  cut.  lluss.  xiv.  1879,  p.  14. 


STYLO  PS  303 


metamorphosis.  They  have  been  observed  in  several  species  of 
Homoptera ;  and  the  writer  has  a  large  Pentatomicl  bug  of 
the  genus  Collided,  which  bears  a  female 
Strepslpteron  apparently  of  large  size.  This 
bug  1  is  abundant  and  widely  distributed  in 
Eastern  Asia,  and  it  may  prove  compara- 
tively easy  to  keep  stylopised  examples 
under  observation.  Both  v.  Siebold  and 
Nassonofif  think  parthenogenesis  occurs  in 
Strepsiptera,  but  there  appear  to  be  no  facts  FlG>  i56.-Abdpmen  of  a 

wasp      (Polistes     heb- 

to  warrant  this  supposition.  Von  Siebold  rams)  with  a  strep- 
speaks  of  the  phenomena  of  Strepsipterous  gg^  ^^ 
reproduction  as  paedogenesis,  or  pseudo-  dorsal  plates  of  the 

j  •          i  -,-,  wasp's  abdomen  being 

paedogenesis,  but  we  must  agree  with  removed.  «,  Project 
Meinert  that  they  cannot  be  so  classed.  tion  of  Pai-t  of  the 

mi  i          f  c  •  i-         f  parasite  ;    b,    line    in- 

Ihe  males  of  Strepsiptera  live  for  only  a        dicating  the  position 
very  short    time,    and    are   very   difficult   of        of  the  remove<l  Dorsal 

lllfltf* 

observation.  According  to  Hubbard  the 
males  of  Xenos  dash  about  so  rapidly  that  the  eye  cannot  see 
them,  and  they  create  great  agitation  amongst  the  wasps  in  the 
colonies  of  which  they  are  bred.  Apparently  they  are  produced  in 
great  numbers,  and  their  life  consists  of  only  fifteen  or  twenty 
minutes  of  fiery  energy.  The  males  of  Stylops  are  not  exposed 
to  such  dangers  as  those  of  Xenos,  and  apparently  live  somewhat 
longer — a  day  or  two,  and  even  three  days  are  on  record.  The 
individuals  of  Andrena  parasitised  by  Stylops  are  apparently 
greatly  affected  in  their  economy  and  appear  earlier  in  the  season 
than  other  individuals ;  this  perhaps  may  be  a  reason,  coupled 
with  their  short  lives,  for  their  being  comparatively  rarely  met 
with  by  entomologists. 

It  is  not  possible  at  present  to  form  a  valid  opinion  as  to 
whether  Stylopidae  are  a  division  of  Coleoptera  or  a  separate 
Order.  Von  Siebold  considered  them  a  distinct  Order,  and 
Nassonoff,  who  has  recently  discussed  the  question,  is  also  of  that 
opinion. 

1  Named  by  Mr.  Distant  Callidea  baro ;  according  to  the  Brussels  catalogue  of 
Hexniptera,  Chrysocoris  yrandis  var.  baro. 


CHAPTEE   VI 

LEPIDOPTERA — OR    BUTTERFLIES    AND    MOTHS 

Order  VI.     Lepidoptera. 

Wings  four ;  body  and  wings  covered  with  scales  usually  varie- 
gate in  colour,  anil  <>n  the  body  frequent!!/  lllore  °r  less  like 
lair:  nervures  moderate  in  number,  at  the  prripJiery  of 
one  winy  not  exceeding  fifteen,  but  little  irregular ;  eross- 
nervules  not  more  than  four,  there  being  usually  only  one  or 
two  closed  cells  on  each  wing,  occasionally  none.  Imago 
with  mouth  incapable  of  biting,  'usually  forming  a  long 
coiled  proboscis  capable  of  protrusion.  Metamorphosis  great 
and  abrupt ;  the  wings  developed  inside  the  bod// ;  the  larva 
with  large  or  moderate  head  and  strong  mandibles.  Pupa 
with  the  apt>i'inl,iges  usu«U  tj  nd pressed  and  cemented  to  the 
body  so  that  it  presents  «  mnre  or  less  even,  horny  exterior, 
occasionally  varied  by  projections  that  are  not  the  appendages 
and  that  may  make  the  form  very  irregular:  in  many 
of  the  smaller  forms  the  appendages  are  only  imperfectly 
cemented  to  the  body. 

LEPIDOPTERA,  or  butterflies  and  moths,  are  so  far  as  ornament  is 
concerned  the  highest  of  the  Insect  world.  In  respect  of 
intelligence  the  Order  is  inferior  to  the  Hymenoptera,  in  the 
mechanical  adaptation  of  the  parts  of  the  body  it  is  inferior  to 
Coleoptera,  and  in  perfection  of  metamorphosis  it  is  second  to 
Diptera.  The  mouth  of  Lepidoptera  is  quite  peculiar;  the  pro- 
boscis— the  part  of  the  apparatus  for  the  prehension  of  food- 
is  anatomically  very  different  from  the  proboscis  of  the  other 
Insects  that  suck,  and  finds  its  nearest  analogue  in  the  extreme 
elongation  of  the  maxillae  of  certain  Coleoptera,  e.g.  Nemognatlut. 


VI 


LEPIDOPTERA 


305 


The  female  has  no  gonapophyses,  though  in  certain  excep- 
tional forms  of  Tineidae,  there  are  modifications  of  structure 
connected  with  the  terminal  segments,  that  have  as  yet  been 
only  imperfectly  investigated.  As  a  rule,  the  egg  is  simply 
deposited  on  some  living  vegetable  and  fastened  thereto. 
Lepidoptera  are  the  most  exclusively  vegetarian  of  all  the  Orders 
of  Insects ;  a  certain  number  of  their  larvae  prey  on  Insects 
that  are  themselves  filled  with  vegetable  juices  (Coccidae, 


FIG.  157. — Metamorphosis  of  a  Lepidopteron  (Rhegmatophila  alpinct,  Notodontidae). 
(After  Poujade,  Ann.  Soc.  cnt.  France,  1891.)  Europe.  A,  Egg  ;  B,  young  larva, 
about  to  moult  ;  C,  adult  larva  ;  D,  head  and  first  body-segment  of  adult  larva, 
magnified  ;  E,  pupa,  x  £  ;  F,  male  moth  in  repose  ;  G,  female  moth  iu  repose. 

Aphidae)  and  a  very  small  number  (Tinea,  etc.)  eat  animal 
matter.  In  general  the  nutriment  appears  to  be  drawn  ex- 
clusively from  the  fluids  of  the  vegetables,  the  solid  matter 
passing  from  the  alimentary  canal  in  large  quantity  in  the  form 
of  little  pellets  usually  dry,  and  called  frass.  Hence  the 
quantity  of  food  ingested  is  large,  and  when  the  individuals 
unduly  increase  in  number,  forest  trees  over  large  areas  are 
sometimes  completely  defoliated  by  the  caterpillars. 

Lepidoptera  pass  a  larger  portion  of  their  lives  in  the  pupal 
stage  than  most  other  Insects  do  ;  frequently  during  nine  months 
of  the  year  the  Lepidopteron  may  be  a  pupa.  In  other  Orders  of 

VOL.   VI  X 


306  LEPIDOPTERA 


CHAP. 


Insects  it  would  appear  that  the  tendency  of  the  higher  forms  is 
to  shorten  the  pupal  period,  and  when  much  time  has  to  he 
passed  between  the  end  of  the  feeding  up  of  the  larva  and  the 
appearance  of  the  imago,  to  pass  this  time  as  much  as  possible 
in  the  form  of  a  resting-larva,  and  as  little  as  may  be  in  the 
form  of  a  pupa  ;  in  Lepidoptera  the  reverse  is  the  case  ;  the 
resting-larva  period  being  usually  reduced  to  a  day  or  two. 
Hence  we  can  understand  the  importance  of  a  hard  skin  to  the 
pupa.  There  are,  however,  numerous  Lepidopterous  pupae  where 
the  skin  does  not  attain  the  condition  of  hardness  that  is 
secured  for  the  higher  forms  by  the  chitinous  exudation  we 
have  mentioned ;  and  there  are  also  cases  where  there  is  a  pro- 
longed resting-larva  period:  for  instance  Galleria  mellonella 
spins  a  cocoon  in  the  autumn  and  remains  in  it  as  a  resting 
larva  all  the  winter,  becoming  a  pupa  only  in  the  spring.  In 
many  of  these  cases  the  resting-larva  is  protected  by  a  cocoon. 
It  is  probable  that  the  chief  advantage  of  the  perfect  chitinous 
exudation  of  the  Lepidopterous  pupa  is  to  prevent  the  tiny, 
complex  organisation  from  the  effects  of  undue  transpiration. 
Bataillon  has  suggested  that  the  relation  of  the  fluid  contents  of 
the  pupa  to  air  and  moisture  are  of  great  importance  in  the 
physiology  of  metamorphosis. 

The  duration  of  life  is  very  different  in  various  forms 
of  Lepidoptera.  It  is  known  that  certain  species  (Ephestia, 
Jcuehniella,  e.g.*)  may  go  through  at  least  five  generations  a  year. 
On  the  other  hand,  certain  species  that  feed  on  wood  or  roots 
may  take  three  years  to  complete  their  life-history ;  and  it  is 
probable  that  some  of  the  forms  of  Hepialidae  are  even  longer 
lived  than  this. 

Lepidoptera  have  always  been  a  favourite  Order  with  ento- 
mologists, but  no  good  list  of  the  species  has  ever  been  made, 
and  it  would  be  a  difficult  matter  to  say  how  many  species  are 
at  present  known,  but  it  can  scarcely  be  less  than  50,000.  In 
Britain  we  have  about  2000  species. 

The  close  affinity  of  the  Order  with  Trichoptera  has  long 
been  recognised :  Reaumur  considered  the  latter  to  be  practically 
Lepidoptera  with  aquatic  habits,  and  Speyer  pointed  out  the 
existence  of  very  numerous  points  of  similarity  between  the 
two.  Brauer  emphasised  the  existence  of  mandibles  in  the 
nymph  of  Trichoptera  as  an  important  distinction :  the  pupa 


VI 


EXTERNAL  STRUCTURE 


307 


of  Micropteryx  (Fig.  211)  has  however  been  recently  shown  to 
be  similar  to  that  of  Trichoptera,  so  that  unless  it  should  be 
decided  to  transfer  Micropteryx  to  Trichoptera,  and  then  define 
Lepidoptera  and  Trichoptera  as  distinguished  by  the  condition  of 
the  pupa,  it  would  appear  to  be  very  difficult  to  retain  the  two 
groups  as  distinct. 

Structure  of  Imago. — The  head  of  a  Lepidopteroii  is  in  large 
part  made  up  of  the  compound  eyes ;  in  addition  to  these  it 
frequently  bears  at  the  top  a  pair  of  small,  simple  eyes  so  much 
concealed  by  the  scales  as  to  cause  us  to  wonder  if  seeing 
be  carried  on  by  them.  The  larger  part  of  the  front  of  the 
head  is  formed  by  the  clypeus,  which  is  separated  by  a  well- 


FIG.  158. — External  structure  of  a  female  butterfly,  Anosia pleswppus.  (After  Scudcler.) 
«,  Base  of  antenna  ;  b,  pronotum  ;  b",  scutum  of  mesothorax  ;  c,  clypeus  ;  ex,  coxa  ; 
d,  scutellum  ;  d1,  scutellum  of  metathorax  ;  e,  post-scutellum  (  =  base  of  phragma)  ; 
em,  epimerou  ;  ep,  episternum  ;  /,  scutum  of  metathorax  ;  m,  basal  part  of  pro- 
boscis (  =  maxilla);  o,  eye;  p,  labial  palp;  /•,  mesosteruum  ;  s,  prothoracic 
spiracle  ;  t,  tegula  ;  tr,  trocliauter  ;  1-9,  dorsal  plates  of  abdomen. 

marked  line  from  the  epicranium,  the  antennae  being  inserted 
on  the  latter  near  its  point  of  junction  with  the  former.  There 
is  sometimes  (Saturnia,  Castnici)  on  each  side  of  the  clypeus  a 
deep  pocket  projecting  into  the  head-cavity.  The  other  parts  of 
the  head  are  but  small.  The  occipital  foramen  is  very  large.' 

The  antennae  are  always  conspicuous,  and  are  very  various 
in  form  ;  they  are  composed  of  numerous  segments,  and  in  the 
males  of  many  species  attain  a  very  complex  structure,  especially 
in  Bornbyces  and  Fsychidae ;  they  doubtless  function  in  such 
cases  as  sense-organs  for  the  discovery  of  the  female. 

The  largest  and  most  important  of  the  mouth-parts  are  the 
maxillae  and  the  labial  palpi,  the  other  parts  being  so  small  as 
to  render  their  detection  difficult.  The  labruni  is  a  very  short, 

1  Kellogg,  Kansas  Quarterly,  ii.  1893,  p.  51,  plate  II. 


308 


LEPIDOPTERA 


CHAP. 


comparatively  broad  piece,  visible  on  the  front  edge  of  the 
clypeus  ;  its  lateral  part  usually  forms  a  prominence  which  has 
often  been  mistaken  for  a  mandible ;  Kellogg  has  applied  the 
term  "  pilifer  "  to  this  part.  In  the  middle  of  the  labrum  a  small 
angular  or  tongue-like  projection  is  seen  just  over  the  middle  of 
the  base  of  the  proboscis ;  this  little  piece  is  considered  by 
several  authorities  to  be  an  epipharynx. 

MANDIBLES. — Savigny,  Westwood,  and  others  considered  the 
parts  of  the  labrum  recently  designated  pilifers  by  Kellogg  to 
be  the  rudimentary  mandibles,  but  Walter  has  shown  that  this 


FIG.  159. — Mouth  of  Lepidoptera.  Tiger-moth,  Arctia  cajn.  A,  Seen  from  front  :  B, 
from  front  and  below.  «,  Clypeus  ;  b,  labrum  ;  c,  epipharynx  ;  d,  mandibular 
area  ;  d',  prominence  beneath  mandibular  area ;  e,  one  side  of  haustellum  or  pro- 
boscis ;  f,  maxillary  palp  ;  g,  labial  palp. 

is  not  the  case.1  The  mandibles  are  usually  indistinguish- 
able, though  they,  or  some  prominence  possibly  connected  with 
them,2  may  frequently  be  detected  in  the  neighbourhood  of 
the  pilifers ;  they  are,  according  to  Walter,  largest  and  most 
perfectly  developed  in  Erioceplmla,  a  genus  that  was  not  dis- 
tinguished by  him  from  Micropteryx  and  was  therefore  termed 
"  niedere  Micropterygiuen,"  i.e.  lower  Micropteryges.  The 
opinion  entertained  by  Walter  that  Micropteryx  proper  (his 
"  hohere  Micropteryginen  ")  also  possesses  rudimentary  mandibles 
is  considered  by  Dr.  Chapman,  no  doubt  with  reason,  to  be 
erroneous.3  The  mandibles,  however,  in  the  vast  majority  of 
Lepidoptera  can  scarcely  be  said  to  exist  at  all  in  the  imago ; 
there  being  only  an  obtuse  projection  —  without  trace  of 

1  Jena.  Zcitschr.  Naturw.  xviii.  1885,  p.  751. 

;  The  writer  is  not  quite  convinced  that  the  supposed  mandibles  of  these  Macro- 
lepidoptera  are  really  entitled  to  be  considered  as  such. 
3  Tr.  cnt.  Soc.  London,  1893,  p.  263. 


vi  MOUTH-PARTS  309 

articulation — on  each  side  of  the  labrum  ;  and  even  this  pro- 
jection is  usually  absent.  Meinert  recognised  these  projections  as 
mandibles  in  Smerinthus  popttli,  and  Kellogg  in  Protoparce  Caro- 
lina, another  large  Sphinx  moth.  They  appear  to  be  unusually 
well  developed  in  that  group.  In  Castnia  they  are  even  more 
definite  than  they  are  in  Sphingidae. 

The  MAXILLAE  are  chiefly  devoted  to  the  formation  of  the 
proboscis.  Their  basal  portions  are  anatomically  very  indefinite, 
though  they  exist  very  intimately  connected  with  the  labium. 
Each  usually  bears  a  small  tubercle  or  a  segmented  process,  the 
representative  of  the  maxillary  palpus.  The  proboscis  itself  con- 
sists of  the  terminal,  or  outer,  parts  of  the  two  maxillae,  which 
parts  are  closely  and  beautifully  coadapted  to  form  the  spirally 
coiled  organ,  that  is  sometimes,  though  incorrectly,  called  the  tongue. 
The  exact  morphology  of  the  Lepidopterous  proboscis  has  not 
been  established.  The  condition  existing  in  the  curious  family 
Prodoxidae  (see  p.  432),  where  a  proboscis  coexists  with  another 
structure  called  a  maxillary  tentacle,  suggests  a  correspondence 
between  the  latter  and  the  galea  of  a  typical  maxilla ;  and 
between  the  proboscis  and  the  lacinia  or  inner  lobe  of  a 
maxilla :  but  J.  B.  Smith  is  of  opinion  that  the  tentacle  in 
question  is  a  prolongation  of  the  stipes.  The  condition  of  the 
parts  in  this  anomalous  family  (Prodoxidae)  has  not,  however, 
been  thoroughly  investigated,  and  Packard  takes  a  different 
view  of  the  proboscis ;  he  considers  that  "  it  is  the  two  galeae 
which  become  elongated,  united  and  highly  specialised  to  form 
the  so-called  tongue  or  glossa  of  all  Lepidoptera  above  the 
Eriocephalidae."  The  proboscis  in  some  cases  becomes  very 
remarkable,  and  in  certain  Sphingidae  is  said  to  attain,  when 
unrolled,  a  length  of  ten  inches.  In  some  cases  the  maxillary 
lobes  do  not  form  a  proboscis,  but  exist  as  delicate  structures, 
pendulous  from  the  mouth,  without  coadaptation  (Zeuzera  aesculi, 
the  Wood -leopard  moth).  In  other  forms  they  are  absent 
altogether  (Cossus,  e.g.},  and  in  Jfcpialus  we  have  failed  to  detect 
any  evidence  of  the  existence  of  the  maxillae.  On  the  other 
hand,  in  Micropteryx  the  maxillae  are  much  more  like  those  of  a 
mandibulate  Insect ;  and  various  other  Microlepidoptera  approach 
more  or  less  a  similar  condition.  In  the  genus  last  mentioned 

1  Amcr.  Natural,  xxix.   1895,    p.    637.     It  should  be  recollected  that  many 
Lepidoptera  do  not  possess  any  proboscis. 


310  LEPIDOPTERA  CHAP. 

the  maxillary  palpi  are  largely  developed,  flexible  and  slender. 
According  to  Walter  various  forms  of  palpus  intermediate  between 
that  of  Micropteryx  and  the  condition  of  rudimentary  tubercle 
may  be  found  amongst  the  Microlepidoptera,1 

LABIUM. — The  labial  palpi  are  usually  largely  developed, 
though  but  little  flexible ;  they  form  conspicuous  processes 
densely  covered  with  scales  or  hairs,  and  curve  forwards  or  up- 
wards, rarely  downwards,  from  the  under  side  of  the  head,  some- 
what in  the  fashion  of  tusks.  The  other  parts  of  the  labium 
are  frequently  represented  merely  by  a  membranous  structure, 
united  with  the  maxillae  and  obstructing  the  cavity  of  the 
pharynx.  Where  the  proboscis  is  absent  it  is  difficult  to  find 
any  orifice  leading  to  the  alimentary  canal,  such  opening  as 
may  exist  being  concealed  by  the  overhanging  clypeus  and 
labium.  In  some  forms,  Saturnia,  e.g.,  there  appears  to  be  no 
buccal  orifice  whatever.  In  Hepialus  the  labium  is  in  a  very 
unusual  condition  ;  it  projects  externally  in  the  position  usually 
occupied  by  the  labial  palpi,  these  organs  being  themselves 
extremely  short.  It  is  very  difficult  to  form  an  opinion  as  to 
the  structure  of  the  labium  and  other  mouth -parts  when  the 
maxillae  are  not  developed,  as  in  these  cases  the  parts  are  of 
a  delicate  membranous  nature,  and  shrivel  after  death.  This 
is  the  explanation  of  the  fact  that  in  descriptive  works  we  find 
vague  terms  in  use  such  as  "  mouth  aborted  "  or  "  tongue  absent." 

The  mouth  of  the  Lepidopterous  imago  is  a  paradoxical 
structure ;  it  differs  very  greatly  from  that  of  the  larva,  the 
changes  during  metamorphosis  being  extreme.  We  should  thus 
be  led  to  infer  that  it  is  of  great  importance  to  the  creatures ; 
but,  on  the  other  hand,  the  various  structures  that  make  up  the 
mouth,  as  we  have  remarked,  are  frequently  absent  or  reduced  to 
insignificant  proportions  ;  and  even  in  forms  where  the  apparatus 
is  highly  developed  the  individuals  seem  to  be  able  to  accomplish 
oviposition  without  taking  food,  or  after  taking  only  very  minute 
quantities.  It  is  therefore  difficult  to  understand  why  so  great 
a  change  should  occur  during  the  metamorphosis  of  the  Insects 
of  this  Order.  It  has  been  ascertained  that  in  some  forms  where 
the  mouth  is  atrophied  the  stomach  is  in  a  correlative  condition  ; 
but  we  are  not  aware  that  any  investigations  have  been  made 
as  to  whether  this  correspondence  is  general  or  exceptional. 

1  Jena.  Zdtschr.  Natunv.  xviii.  1885,  p.  168. 


vi  EXTERNAL  STRUCTURE  3 1  I 

The  exact  mode  in  which  the  proboscis  acts  is  in  several 
respects  still  obscure,  the  views  of  Burmeister  and  Newport  being 
in  some  points  erroneous.  Towards  the  tip  of  the  proboscis 
there  are  some  minute  but  complex  structures  considered  by 
Fritz  Miiller  to  be  sense-organs,  and  by  Breitenbach  to  be 
mechanical  instruments  for  irritating  or  lacerating  the  delicate 
tissues  of  blossoms.  It  is  probable  that  Miiller's  view  will  prove 
to  be  correct.  Nevertheless  the  proboscis  has  considerable 
power  of  penetration ;  there  being  a  moth,  "  Ophideres  fullonica" 
that  causes  considerable  damage  to  crops  of  oranges  by  inserting 
its  trunk  through  the  peel  so  as  to  suck  the  juices.1  The  canal 
formed  by  each  maxilla  opens  into  a  cavity  inside  the  front  part 
of  the  head.  This  cavity,  according  to  Burgess,2  is  a  sort  of  sac 
connected  with  five  muscles,  and  by  the  aid  of  this  apparatus  the 
act  of  suction  is  performed :  the  diverticulum  of  the  alimentary 
canal,  usually  called  a  sucking-stomach,  not  really  possessing  the 
function  formerly  attributed  to  it. 

The  PROTHORAX  is  very  small,  being  reduced  to  a  collar,  be- 
tween the  head  and  the  alitrunk,  of  just  sufficient  size  to  bear  the 
front  pair  of  legs.  Its  most  remarkable  feature  is  a  pair  of  pro- 
cesses, frequently  existing  on  the  upper  surface,  called  "  patagia." 
These  in  many  cases  (especially  in  Noctuidae)  are  lobes  capable 
of  considerable  movement,  being  attached  only  by  a  narrow-  base. 
In  Hepialus,  on  the  contrary,  they  are  not  free,  but  are  merely 
indicated  by  curved  marks  on  the  dorsum.  The  patagia  are 
styled  by  many  writers  "  tegulae."  They  are  of  some  interest  in 
connection  with  the  question  of  wing -like  appendages  on  the 
prothorax  of  Palaeozoic  insects,  and  they  have  been  considered 
by  some  writers3  to  be  the  equivalents  of  true  wings.  The 
MESOTHORAX  is  very  large,  especially  its  upper  face,  the  notum, 
which  is  more  or  less  convex,  and  in  the  higher  forms  attains  a 
great  extension  from  before  backwards.  The  notum  consists  in 
greater  part  of  a  large  anterior  piece,  the  meso-scuturn,  and  a 

1  Amer.  Natiiral.  xiv.  1880,  p.  313. 

-  For  an  account  of  the  structures  at  the  tip  of  the  proboscis  of  this  moth,  and 
of  the  beautiful  manner  in  which  the  lobes  of  the  maxillae  are  dovetailed  together, 
see  Francis  Darwin,  Quart.  J.  Micr.  Sd.  xv.  1875,  p.  385.  For  details  as  to 
numerous  proboscides,  and  as  to  the  difficulties  that  exist  in  comprehending  the 
exact  mode  of  action  of  the  organ,  refer  to  Breitenbach's  papers,  especially  Jena. 
Zcitschr.  Xaturw.  xv.  1882,  p.  151. 

3  See  Cholodkovsky,  Zool.  Anz.  ix.  p.  615  ;  Haase,  t.c.  p.  711  ;.  also  Riley, 
P.  cut.  Soc.  Washington,  ii.  1892,  p.  310. 


3  I  2  LEPIDOPTERA  CHAP. 

smaller  part,  the  meso-scutellum  behind.  In  front  of  the  scutum 
there  is  a  piece  termed  prae-scutum  by  Burgess.  It  is  usually 
small  and  concealed  by  the  front  part  of  the  scutum ;  but 
in  Hepialus  it  is  large  and  horizontal  in  position.  It  is  of 
importance  as  being  the  chief  point  of  articulation  with  the  pro- 
thorax.  The  scutellum  is  more  or  less  irregularly  rhomboidal  in 
form  ;  its  hinder  margin  usually  looks  as  if  it  were  a  lobe  or  fold 
placed  in  front  of  the  base  of  the  abdomen  or  metathorax,  accord- 
ing to  whether  the  latter  is  concealed  or  visible.  In  some  of  the 
higher  forms  this  meso-scutellar  lobe  is  prominent,  and  there 
may  be  seen  under  its  projection  a  piece  that  has  been  called 
the  post-scutellum,  and  is  really  the  base  of  the  great  meso- 
phragma,  a  chitinous  piece  that  descends  far  down  into  the 
interior  of  the  body.  In  addition  to  the  front  pair  of  wings  the 
inesothorax  bears  on  its  upper  surface  another  pair  of  appendages, 
the  tegulae  :  in  the  higher  forms  they  are  of  large  size  ;  they  are 
fastened  on  the  front  of  the  inesothorax,  and  extend  backwards 
over  the  joint  of  the  wing  with  the  body,  being  densely  covered 
with  scales  so  that  they  are  but  little  conspicuous.  These 
appendages  are  frequently  erroneously  called  patagia,  but  have 
also  been  called  scapulae,  pterygodes,  paraptera,  and  shoulder- 
tufts,  or  shoulder-lappets.  The  lower  surface  of  the  inesothorax 
is  much  concealed  by  the  large  and  prominent  coxae,  but  the 
sternum  and  the  two  pleural  pieces  on  each  side,  episternum  and 
epimeron,  are  easily  detected.  The  area  for  attachment  of  the 
anterior  wing  on  each  side  is  considerable,  and  appears  to  be  of 
rather  complex  structure  ;  its  anatomy  has  been,  however,  but 
little  studied. 

The  METATHORAX  is  small  in  comparison  with  the  preceding 
segment,  to  which  it  is  intimately  co-adapted,  though  the  two 
are  really  connected  only  by  delicate  membrane,  and  can  conse- 
quently  be  separated  with  ease  by  dissection.  The  metanotum 
consists  of  (1)  the  scutum,  which  usually  appears  externally  as 
an  anterior  piece  on  each  side  ;  (2)  the  scutellum,  forming  a 
median  piece  placed  behind  the  scutum,  which  it  tends  to 
separate  into  two  parts  by  its  own  extension  forwards.  In  order 
to  understand  the  structure  of  the  metathorax  it  is  desirable  to 
dissect  it  off  from  the  larger  anterior  segment,  and  it  will  then 
be  found  that  its  appearance  when  undissected  is  deceptive, 
owing  to  its  being  greatly  arched,  or  folded  in  the  antero- 


vi  EXTERNAL  STRUCTURE  3  I  3 

posterior  direction.  A  broad,  but  short  phragma  descends  from 
the  hind  margin  of  the  metascutellum  into  the  interior  of  the 
body.  It  should  be  noted  that  though  the  metanotum  is  forced, 
as  it  were,  backwards  by  the  great  extension  of  the  mesonotum  in 
the  middle  line  of  the  body,  yet  at  the  sides  the  metanotum  creeps 
forward  so  as  to  keep  the  points  of  attachment  of  the  hind  wings 
near  to  those  of  the  front  wings.  In  many  forms  of  Hesperiidae, 
Sphingidae,  Noctuidae,  etc,  the  true  structure  of  the  metanotum 
is  further  concealed  by  the  back  of  the  mesoscutelluni  reposing 
on,  and  covering  it. 

Difference  of  opinion  exists  as  to  the  thoracic  SPIRACLES  ;  there 
is  one  conspicuous  enough  in  the  membrane  behind  the  pronotum, 
and  it  is  thought  by  some  writers  that  no  other  exists.  West- 
wood  and  Scudder,  however,  speak  of  a  mesothoracic  spiracle,  and 
Dr.  Chapman  considers  that  one  exists.  Minot  describes l  a 
structure  behind  the  anterior  wing,  and  thinks  it  may  be  an 
imperfect  spiracle,  and  we  have  found  a  similar  stigma  in 
Saturnia  pavonia.  At  the  back  of  the  thorax  there  is  on  each 
side  in  some  Lepidoptera  (Noctuidae,  Arctia,  etc.),  a  curious  large 
cavity  formed  by  a  projection  backwards  from  the  sides  of  the 
metasternum,  and  a  corresponding  development  of  the  pleura  of 
the  first  abdominal  segment.  Minot  and  others  have  suggested 
that  this  may  be  an  organ  of  hearing. 

The  ABDOMEN  differs  according  to  the  sex.  In  the  female 
seven  segments  are  conspicuous  dorsally,  but  only  six  ventrally, 
because  the  first  segment  is  entirely  membranous  beneath,  and 
is  concealed  between  the  second  abdominal  ventral  plate  and 
the  posterior  coxae.  Besides  these  segments  there  are  at  the 
hind  end  two  others  smaller,  more  or  less  completely  with- 
drawn into  the  body,  and  in  certain  cases  forming  an  ovipositor. 
These  nine  segments  are  usually  considered  to  constitute  the 
abdomen;  but  according  to  Peytoureaiv  a  tenth  dorsal  plate  is 
represented  on  either  side  of  the  anal  orifice,  though  there  is  no 
trace  of  a  corresponding  ventral  plate.  In  the  male  the  segments, 
externally  conspicuous,  are  one  more  than  in  the  female.  According 
to  the  authority  quoted,3  this  sex  has  also  truly  ten  abdominal 
segments,  the  ninth  segment  being  withdrawn  to  a  greater  or 

1  Fourth  Rep.  U.S.  Entom.  Commission,  1885,  p.  49. 

2  C.R.  Ac.  Set.  Paris,  cxviii.  1894,  p.  360  ;  and  his  Thesis,  Bordeaux,  1895. 
3  C.R.  Ac.  Set.  Paris,  cxviii.  1894,  p.  542. 


LEPIDOPTERA 


CHAP. 


less  extent  to  the  inside  of  the  body,  and  modified  to  form  part  of 
a  copulatory  apparatus  ;  its  dorsal  portion  bears  a  process  called  the 
"  uncus  "  ;  the  anal  orifice  opens  on  the  inner  face  of  this  process, 
and  below  it  there  is  another  process — developed  to  a  greater  or 
less  extent— called  the  "  scaphium."  The  ventral  portion  of  the 
ninth  segment  bears  a  lobe,  the  "  saccus  "  (Peytoureau,  I.e.').  On 
each  side  of  the  ninth  abdominal  segment  there  is  a  process  called 
the  "  valve,"  the  internal  wall  of  which  bears  some  hook-like  or 
other  processes  called  "  harpes  "  ;  it  is  continued  as  a  membrane 
surrounding  the  "oedeagus,"  or  penis,  and — bearing  more  or 
less  distinct  prominences — connects  with  the  scaphium.  In  many 
forms  the  parts  alluded  to,  other  than  the  valves,  are  concealed 

by  the  latter,  which 
come  together  when 
closed,  and  may  lie 
covered  externally  with 
scales  like  the  rest  of 
the  abdomen.  Peytou- 
reau considers  that  the 
uncus  is  really  the  dorsal 
plate  of  a  tenth  segment, 
and  that  the  scaphium 
is  the  tenth  ventral 
Thus,  according 
view,  the  ninth 


FIG.  160. — Acherontia  (ifr<i/><~is.  The  termination  of  <J 
body,  one  side  removed.  7A',  Ninth  dorsal  plate  ; 
IX',  ninth  ventral  ;  s,  lobe,  saccus,  of  ninth 
ventral  plate  ;  A',  tenth  dorsal  plate,  or  uncus  ; 
sc,  scaphium,  or  tenth  ventral  plate  ;  «,  position  of 
anus  ;  b,  chitinised  band  of  scaphium  ;  V,  valve  or  Segment  IS  extensive  and 
clasper  :  c,  hooks  or  harpes,  of  clasper  ;  p,  penis  complex  ],eing  very 
(or  oedeagus).  (Alter  Peytoureau.)  -1- 

highly    modified    in    all 

its  parts :  while  the  tenth  segment  is  greatly  reduced.  The 
structure  of  the  male  organs  is  simpler  in  Lepidoptera,  and  less 
varied  than  it  is  in  the  other  great  Orders  of  Insects.  There 
are  seven  pairs  of  abdominal  spiracles  on  the  upper  parts  of  the 
membranous  pleurae. 

LEGS. — The  legs  are  long,  slender,  covered  with  scales,  and 
chiefly  remarkable  from  the  fact  that  the  tibiae  sometimes  bear 
articulated  spurs  on  their  middle  as  well  as  at  the  tip.  The 
front  tibia  usually  possesses  on  its  inner  aspect  a  peculiar 
mobile  pad ;  this  seems  to  be  in  some  cases  a  combing  organ  ; 
it  also  often  acts  as  a  cover  to  peculiar  scales.  The  tarsi 
are  five-jointed,  with  two  small  claws  and  a  small  apparatus, 


vi  WINGS  3  I  5 

the   functional  importance  of  which    is    unknown,  between    the 
claws. 

Wings. — The  wings  are  the  most  remarkable  feature  of  this 
Order ;  it  is  to  them  that  butterflies  owe  their  beauty,  the  sur- 
faces of  the  wings  being  frequently  adorned  with  colours  and 
patterns  of  the  most  charming  and  effective  nature.  These 
effects  are  due  to  minute  scales  that  are  implanted  in  the  wing- 
membrane  in  an  overlapping  manner,  somewhat  similar  to  the 
arrangement  of  slates  on  the  roof  of  a  house.  The  scales  are  very 
readily  displaced,  and  have  the  appearance  of  a  silky  dust.  "We 
shall  describe  their  structure  and  allude  to  their  development 
subsequently.  The  wings  are  usually  of  large  size  in  com- 
parison with  the  Insect's  body :  in  the  genus  Morplio,  the 
most  gorgeous  of  the  butterflies,  they  are  enormous,  though  the 
body  is  small ;  so  that  when  deprived  of  these  floats  the  Insect  is 
insignificant.  The  great  expanse  of  wing  is  not  correlative  with 
great  powers  of  flight,  though  it  is  perhaps  indicative  of  flying  with 
little  exertion ;  for  the  small-winged  Lepidoptera,  Sphingidae, 
etc.,  have  much  greater  powers  of  aerial  evolution  than  the  large- 
winged  forms.  The  area  of  the  wing  is  increased  somewhat  by 
the  fact  that  the  scales  on  the  outer  margin,  and  on  a  part  or  on 
the  whole  of  the  inner  margin,  project  beyond  the  edges  of  the 
membrane  that  bears  them :  these  projecting  marginal  scales  are 
called  fringes.  In  many  of  the  very  small  moths  the  actual  size 
of  the  wing-membranes  is  much  reduced,  but  in  such  cases  the 
fringes  may  be  very  long,  so  as  to  form  the  larger  part  of  the 
surface,  especially  of  that  of  the  hind  wings.  Frequently  the 
hind  wings  are  of  remarkable  shape,  being  prolonged  into  pro- 
cesses or  tails,  some  of  which  are  almost  as  remarkable  as  those 
of  Nemoptera  in  the  Order  Neuroptera. 

The  wings  are  very  rarely  absent  in  Lepidoptera ;  this  occurs 
only  in  the  female  sex,  no  male  Lepidopterous  imago  destitute  of 
wings  having  been  discovered.  Although  but  little  is  known  of 
the  physiology  of  flight  of  Lepidoptera,  yet  it  is  clearly  important 
that  the  two  wings  of  the  same  side  should  be  perfectly  coadapted 
or  correlated.  This  is  effected  largely  by  the  front  wing  over- 
lapping the  hind  one  to  a  considerable  extent,  and  by  the  two 
contiguous  surfaces  being  pressed,  as  it  were,  together.  This  is 
the  system  found  in  butterflies  and  in  some  of  the  large  moths, 
such  as  Lasiocampidae  and  Saturniidae  ;  in  these  cases  the  hind 


316  LEPIDOPTERA 


CHAP. 


wing  always  has  a  large  shoulder,  or  area,  anterior  to  its  point 
of  insertion.  In  most  moths  this  shoulder  is  absent,  but  in  its 
place  there  are  one  or  more  stiff  bristles  projecting  forwards  and 
outwards,  and  passing  under  a  little  membranous  flap,  or  a  tuft 
of  thick  scales  on  the  under  face  of  the  front  wing ;  the  bristle  is 
called  the  "  frenulum,"  the  structure  that  retains  it  a  "  retinaculum." 
In  Cost iiia  (Fig.  162)  and  in  some  Sphingidae  there  is  the  un- 
usual condition  of  a  highly-developed  shoulder  (s)  coexisting  with 
a  perfect  frenulum  (/)  and  retinaculum  (r).  The  frenulum  and 
retinaculum  usually  differ  in  structure,  and  the  retinaculum  in 
position,  in  the  two  sexes  of  the  same  moth  ;  the  male,  which 
in  moths  has  superior  powers  of  flight,  having  the  better  retaining 
organs.  Hampson  says  "  the  form  of  the  frenulum  is  of  great 
use  in  determining  sex,  as  in  the  males  of  all  the  forms  that 
possess  it,  it  consists  of  hairs  firmly  soldered  together  so  as  to 
form  a  single  bristle,  whilst  in  nearly  all  females  it  consists  of 
three  or  more  bristles  which  are  shorter  than  that  of  the  male  ; 
in  one  female  Cossid  I  have  found  as  many  as  nine.  Also  in  the 
large  majority  of  moths  the  retinaculum  descends  from  the  costal 
nervure  in  the  male,  while  in  the  female  it  ascends  from  the 
median  nervure."  This  sexual  difference  in  a  structure  for  the 
discharge  of  a  function  common  to  the  two  sexes  is  a  very  re- 

O  i/ 

markable  fact.  There  are  a  few — very  few — moths  in  which  the 
bases  of  the  hind  wings  are  not  well  coadapted  with  the  front 
wings,  and  do  not  possess  a  frenulum,  and  these  species  possess 
a  small  more  or  less  free  lobe  at  the  base  of  the  front  wing  that 
droops  towards  the  hind  wing,  and  may  thus  help  to  keep  up  an 
imperfect  connexion  between  the  pair  ;  this  lobe  has  been  named 
a  juguin  by  Professor  Comstock.  Occasionally  there  is  a  jugum 
on  the  hind  as  well  as  on  the  front  wing.  There  is  usually  a 
very  great  difference  between  the  front  and  the  hind  wings ;  for 
whereas  in  the  front  wing  the  anterior  portion  is  doubtless  of 
great  importance  in  the  act  of  flight  and  is  provided  with 
numerous  veins,  in  the  hind  wing,  on  the  other  hand,  the  corre- 
sponding part  has  not  a  similar  function,  being  covered  by  the 
front  wing  ;  hence  the  hind  wing  is  provided  with  fewer  ncrvures 
in  the  anterior  region,  the  divisions  of  the  subcostal  being  less 
numerous  than  they  are  in  the  front  wing.  In  the  moths 
possessing  a  jugum  the  two  wings  differ  but  little  from  one 

1  Fauna  of  British  India,  Moths,  i.  1892,  p.  6. 


vi  YVING-NERVURES  3  1 7 

another,  and  it  is  probable  that  they  function  almost  as  four 
separate  wings  instead  of  as  two  pairs. 

WING-NEEVURES. — The  nervures  or  ribs  of  the  wings  are  of 
great  importance  in  Lepidoptera,  as  at  present  they  furnish  the 
chief  characters  for  classification  and  for  the  discussions  of 
phylogeny  that  are  so  numerous  in  entomological  literature. 
On  looking  at  wings  that  have  been  deprived  of  their  scales  it 
will  be  noticed  (Fig.  161)  that  the  ribs  are  much  more  numerous 
at  the  outer  margins  than  they  are  near  the  points  of  attachment 
of  the  wings,  and  that  there  is  usually  but  one  cell  (or  area  com- 
pletely enclosed  by  ribs).  This  latter  point  is  one  of  the  chief 
peculiarities  of  the  Lepidopterous  wing  ;  in  Insect-wings  generally 
the  number  of  cells  in  proportion  to  the  area  of  the  wings  and  to 
the  number  of  nervures  is  greater  than  it  is  in  Lepidoptera,  for 
in  the  latter  there  are  few  or  no  cross-nervures.  Hence  there  is 
sometimes  no  closed  cell  at  all  on  the  wing  (Fig.  161,  II.  B). 
The  maximum  number  of  closed  cells  is  six  ;  this  is  found  in 
some  species  of  Micropteryx,  while  in  Hepialus  there  may  be 
three  or  four ;  but  the  rule  is  that  there  is  only  one  cell  in  the 
Lepidopterous  wing.  When  the  number  of  cells  is  increased 
this  is  not  necessarily  due  to  an  increase  in  the  cross-nervures;  and 
in  fact  it  is  generally  due  to  irregular  forking  or  to  the  sinuous 
form  of  the  longitudinal  nervures  themselves  (see  wing  of  Castnia, 
Fig.  162,  A.).  Some  authorities  consider  that  all  transverse  or 
cross-veins  in  Lepidoptera  are  merely  portions  of  longitudinal 
veins  having  diverted  courses.  When  a  portion  of  a  nervure 
beyond  the  basal  or  primary  portion  serves  as  a  common  piece 
to  two  forked  parts  external  to  it,  it  is  called  a  stalk  (Fig.  162, 
A,  e).  There  are  cases  in  which  the  furcation  takes  place  in  the 
opposite  direction,  so  that  a  nervure  is  double  at  the  base  of  the 
wing  (Fig.  161,  I,  A,  la,  and  B,  16).  This  important  condition 
has  not  yet  been  adequately  discussed. 

Turning  to  the  mode  of  designation  of  the  nervures,1  we  may 

1  It  is  impossible  for  us  to  treat  of  the  difficulties  that  exist  on  this  point,  and 
we  must  refer  the  student  to  the  pamphlet,  "The  Venation  of  the  Wings  of 
Insects,"  by  Prof.  Comstock,  Ithaca,  1895,  being  a  reprint,  with  an  important 
pivfatory  note,  from  the  Elements  of  Insect  Anatomy,  by  J.  H.  Comstock  and  V.  L. 
Kellogg,  also  to  Packard's  discussion  of  the  subject  in  Mem.  Ac.  Sci.  Wasliiujtvu. 
vii.  1895,  pp.  84-86.  The  method  of  Spuler,  alluded  to  in  these  two  memoirs,  is 
based  on  development,  and,  when  extended,  will  doubtless  have  very  valuable 
results.  See  Spuler,  Zcitschr.  wiss.  Zool.  liii.  1892,  p.  597. 


LEPIDOPTERA 


CHAP. 


commence  by  remarking  that  no  system  satisfactory  from  a 
practical  as  well  as  from  a  theoretical  point  of  view  has  yet  been 
devised.  The  diagrams  given  in  figure  1G1  will  enable  us  to 
explain  the  methods  actually  in  vogue  ;  I.  representing  the  system, 
dating  from  the  time  of  Herrich - Schaeffer,  chiefly  used  by 
British  naturalists,  and  II.  that  adopted  by  Staudinger  and 
Schatz  in  their  recent  great  work  on  the  Butterflies  of  the  world. 
The  three  anterior  nervures  in  both"  front  and  hind  wings 
correspond  fairly  well,  and  are  called,  looking  at  them  where 
they  commence  at  the  base  of  the  wing,  "  costal,"  "  subcostal,"  and 


FIG.  161. — Wing-nervuratiou  of  Lepidoptera.  I,  Diagram  of  moths'  wings  (after  Hamp- 
son)  ;  II,  of  a  butterfly's  wings  (Mi,rji/n>  ini'in'Inux  ,5,  after  Staudinger  and  Schatz). 
A,  front,  B,  hind  wing.  I. — c,  costal  ;  sc,  subcostal  ;  •//(,  median  ;  In.  Ifi,  lr,  in- 
ternal nervures  ;  /,  frenulum  ;  2,  3,  4,  branches  of  median  nervure  ;  5,  lower 
radial;  6,  upper  radial;  7-11,  divisions  of  the  subcostal;  12,  termination  of 
costal  ;  c,  cell  ;  d,  discocellular  nervure.  II. — C,  costal  ;  SC,  subcostal  ;  M,  median  ; 
SM  and  SN,  submedian  nervures  ;  1A,  inner-margin  nervure  ;  UR,  lower  radial  ; 
OR,  upper  radial  ;  SC1  to  SC5,  divisions  of  subcostal  ;  M1  to  M3,  divisions  of  median 
uervure  ;  C,  cell  ;  DC,  discocellulars. 

"  median  "  nervures.  The  nervures  near  the  inner  margin  of  the 
wing  (that  is  the  lower  part  in  our  figures)  differ  much  in  the  front 
and  hind  wings,  consisting  either  of  two  or  of  three  separate 
portions  not  joined  even  at  the  base.  British  entomologists  call 
these  "branches  or  divisions  of  the  internal  nervure":  the 
Germans  call  the  more  anterior  of  them  the  "  submedian,"  and  the 
more  internal  the  "inner-margin  nervure";  they  are  also  frequently 
called  anal  nervures.  The  cross-nervure  that  closes  the  cell  is 
called  discocellular;  when  apparently  composed  of  two  or  three 


WING-NERVULES 


319 


parts  joined  so  as  to  form  angles,  the  parts  are  called,  according 
to  position,  upper,  lower,  and  middle  discocellulars.  One  or  more 
short  spurs  may  exist  on  the  front  part  of  the  basal  portion  of 
the  hind  wing  ;  these  are  called  praecostal.  The  branches  or 
terminal  divisions  of  the  nervures  should  be  called  nervules  ;  they 
are  usually  mentioned  by  the  numbers  shewn  in  the  diagram 
(Fig.  161,  I.).  In  addition  to  this,  it  is  only  necessary  to  re- 
member that  number  2  is  always  assigned  to  the  posterior  division 
of  the  median  nervure,  the  nervules  below  this  being  all  called  1, 
and  distinguished  by  the  addition  of 
a,  I),  c  when  requisite.  This  course 
is  necessary,  because  if  it  were  not 
adopted  the  corresponding  nervules 
on  the  front  and  hind  wings  would 
bear  different  numbers. 

The  use  of  this  system  of  num- 
bers for  the  nervules  is  becoming 
general,  and  it  answers  fairly  well 
for  practical  purposes.  On  the  other 
hand,  extreme  discrepancy  exists  as 
to  the  nomenclature  of  the  nervures 
and  nervules,  and  there  are  almost  as 
many  systems  as  there  are  authorities. 

The  normal  number  of  nervules 
is,  on  the  front  wing,  11+1  or  2 


B 


inner    marginal,    and    on    the 


wng 


+  2  or  3  inner  marginal. 


hind 
In 


genus 


FIG.  162.  —  Wing  -  nervuration  of 
Castnia.  Undersides  of,  A,  front, 
B,  hind  wings,  la,  lb,  Ic,  Irf, 
Inner  marginal  nervnres  ;  2,  lower 
branch  of  median  ;  8,  subcostal 
of  hind  wing  ;  1'2,  subcostal  of 
front  wing;  e,  "stalk"  of  8  and 
9  ;  _/",  frenuluni  ;  r,  retinaculum  ; 
s,  shoulder ;  ij,  articulation  of 


the    aberrant    moths    of    the 

Castnia  the  nervuration  is  unusually 

complex   and   irregular  (Fig.    162),  and  an   analogous  condition 

occurs    in    our    common    Goat  -  moth    (Cossus    ligniperda).       In 

Jfi-jiinliis  and  Micropteryx  (the  jugate  moths  of  Comstock)  the 

hind  wings  are   less  dissimilar  in    nervuration    from    the    front 

wings  than  they  are  in  other  Lepidoptera.1 

Internal  Anatomy.  ~  —  The  alimentary  canal  extends  as  a  long, 

•  The  structure  and  development  of  scales  and  nervures  is  dealt  with  as  part  of 
the  brief  study  of  the  development  of  the  wing,  on  p.  329,  etc. 

2  The  internal  anatomy  of  Lepidoptera  has  not  been  extensively  studied.  For 
information  refer  to  Dufour,  L'.Il.  Ac.  Paris,  xxxiv.  1852,  p.  718;  Scudder,  JJi/tf. 
Xi'/r  England,  i.  1SS9,  p.  47  ;  Minot  and  Bur^rss.  Fourth  Jtcj>.  I'.  S.  Entmn. 
1885,  p.  53. 


320 


LEPIDOPTERA 


CHAP. 


slender  oesophagus  through  the  length  of  the  thorax,  dilating  when 
it  reaches  the  abdomen  to  form  a  tubular  stomach ;  before  this 
it  is  somewhat  enlarged  to  form  an  indistinct  crop,  and  gives  off 
a  large  diverticulum  usually  called  a  sucking  stomach.  According 
to  Burgess,  this  structure  does  not  possess  the  function  ascribed 
to  it  by  this  name,  and  he  terms  it  a  food-reservoir.  The  Mai- 
pi  ghian  tubes  are  six  in  number,  three  on  each  side,  and  each  set 
of  three  unite  to  form  a  common  tube  opening  into  the  posterior 
extremity  of  the  stomach ;  behind  them  the  alimentary  canal 
continues  in  the  form  of  a  slender,  tortuous  intestine,  expanding 


FIG.  163. — Internal  anatomy  of  Lepidoptera.  Section  of  the  body  of  a  female  butterfly, 
Anosia  j>/r.ri/>i>its.  (After  Scudder. )  The  portion  to  the  left  of  the  vertical  line 
more  magnified.  I.  II.  Ill,  thoracic  segments  ;  1-9,  abdominal  segments ;  «, 
antenna  ;  «,  anus  ;  ac,  aortal  chamber  ;  agl,  etc.,  abdominal  ganglia  ;  agl1,  agl~, 
accessory  glands  ;  an,  aorta  ;  br.  brain  ;  c,  colon  ;  cp,  copnlatory  pouch  ;  ex1,  ex-, 
cjc3,  coxae  ;  _/>.  food-reservoir  ;  g1,  suboesophageal  ganglion  ;  h,  dorsal  vessel  ;  i, 
intestine  ;  I  in,  area  filled  by  wing  muscles  ;  Lor,  ovary,  or  egg-tubes  of  left  side  ; 
mi-,  Malpighian  tube  (the  two  others  of  the  right  side  cut  away,  except  small  por- 
tions) ;  ni.c,  maxilla  ;  u,  oviduct  ;  uo,  its  orifice  ;  oe,  oesophagus  ;  ov.c,  end  of  left 
ovary  ;  />,  labial  palp  ;  j/h,  pharynx  ;  r.ov,  terminal  jiarts  of  right  ovarian  tubes, 
turned  to  one  side,  after  the  tubes  have  been  cut  away  ;  &•</,  salivary  duct  ;  sgl, 
salivary  gland  ;  .*//,  .spermatheca  ;  st,  stomach  ;  tg,  thoracic  ganglia  ;  r,  copulatory 
orifice. 

at  the  extremity  of  the  body  to  form  a  rectum.  The  dorsal  or 
circulatory  vessel  commences  near  the  posterior  extremity  of  the 
body,  but  in  the  front  part  of  the  abdomen  is  deflexed  to  pass 
under  the  great  phragma  into  the  thorax,  where  it  rises  abruptly 
to  the  dorsal  wall,  but  is  again  abruptly  deflexed,  forming  a  loop, 
and  is  then  prolonged  above  the  oesophagus  into  the  head  :  at 
the  summit  of  the  thoracic  loop  there  may  be  a  dilatation  called 
the  aortal  chamber.  The  supra-  and  infra-oesophageal  ganglia 
are  consolidated  into  a  mass  pierced  by  the  oesophagus  :  there  is 
a  minute  frontal  ganglion  ;  the  ventral  chain  consists  of  three 
much  approximated  thoracic  ganglia  and  four  abdominal  ganglia 
separated  from  the  thoracic  by  a  long  interval. 


vi  INTERNAL  STRUCTURE EGG  321 

The  male  sexual  organs  consist  of  the  two  testes  placed  in  a 
common  capsule,  from  which  proceed  a  pair  of  contiguous  vasa 
deferentia  (dilated  soon  after  their  origin  to  form  the  vesiculae 
seminales) ;  into  each  vas  there  opens  a  long,  tubular  gland  ;  the 
two  vasa  subsequently  unite  to  form  a  long,  coiled,  ejaculatory 
duct.  It  is  in  the  structure  of  the  female  sexual  organs  that  the 
most  remarkable  of  the  anatomical  characters  of  Lepidoptera  is 
found,  there  being  two  external  sexual  orifices.  The  imago  has, 
in  the  great  majority  of  cases,  four  egg-tubes  in  each  ovary ;  the 
pair  of  oviducts  proceeding  from  them  unite  to  form  a  single  un- 
paired (azygos)  oviduct  which  terminates  by  an  orifice  quite  at 
the  posterior  extremity  of  the  body.  There  is  a  sac,  the  bursa 
copulatrix  or  copulatory  pouch,  which  is  prolonged  in  a  tubular 
manner,  to  open  externally  on  the  eighth  ventral  plate  :  a  tube, 
the  seminal  duct,  connects  the  bursa  with  the  oviduct,  and  on  this 
tube  there  may  be  a  dilatation — the  spermatheca.  Besides  these 
structures  two  sets  of  accessory  glands  open  into  the  oviduct,  an 
unpaired  gland,  and  a  pair  of  glands.  The  development  of  these 
structures  has  been  described  by  Hatchett  Jackson,1  and  exhibits 
some  very  interesting  features.  The  exact  functions  of  the  bursa 
copulatrix  and  of  the  other  structures  are  by  no  means  clear. 
According  to  Riley,2  the  spermatheca  in  Pronvla  contains  some 
curious  radiate  bodies,  and  Godman  and  Salviii  describe  some- 
thing of  the  same  sort  as  existing  in  butterflies.  Several  varia- 
tions in  the  details  of  the  structure  of  these  remarkably  complex 
passages  have  been  described,  and  the  various  ducts  are  some- 
times rendered  more  complex  by  diverticula  attached  to  them. 
Some  noteworthy  diversities  in  the  main  anatomical  features 
exist.  According  to  Cholodkovsky,  there  is  but  one  sexual 
aperture — the  posterior  one — in  Nematois  metallicus  ;  while, 
according  to  Brandt,  the  number  of  egg-tubes  in  a  few  cases 
exceeds  the  normal — four — being  in  Sesia  scoliaeformis  fourteen. 
In  Nematois  metallicus  there  is  individual  variation,  the  number 
of  tubes  varying  from  twelve  to  twenty. 

The  egg  has  been  more  extensively  studied  in  Lepidoptera 
than  in  any  other  Order  of  Insects.  It  displays  great  variety  : 
we  meet  with  elongate  forms  (Fig.  164)  and  flat  forms  like 
buttons,  while  in  Limacodes  (Fig.  83,  Vol.  Y.)  the  egg  is  a 

1  Tr.  Linn.  Soc.  London  (2),  v.  1890,  p.  143. 
"  P.  cut.  Soc.   U'ashiwjton,  ii.  1892,  p.  305. 
VOL.  VI  Y 


322 


LEPIDOPTERA 


CHAP. 


transparent  scale  of  somewhat  inconstant  outline.  Some  are 
coloured  and  mottled  somewhat  after  the  fashion  of  birds'-eggs ; 
this  is  the  case  with  some  eggs  of  Lasiocampidae  and  Liparidae ;  in 
some  the  sculpture  of  the  egg-shell  is  of  the  most  elaborate  char- 
acter (Figs.  77,  78,  Yol.  Y.).  The  egg-shell  or  chorion  is,  accord- 
ing to  Korschelt 1  and  others,  a  cuticular  product  of  the  epithelium 
of  the  egg-chambers  of  the  ovaries.  The  number  of  eggs  deposited 
by  an  individual  differs  greatly  in  different  species,  and  has  been 
ascertained  to  be  variable  within  certain  limits  in  the  same 
species.  Speyer  thought  about  250  to  be  the  average  number 
of  eggs  deposited  by  an  individual.  The  number  in  the  case  of 
Aporia  crataeyi  is  believed  to  be  from  60  to  100,  and  in  some 
Ifepialus  to  be  several  thousands.  The  mode  of  deposition  also 

differs  greatly ;  where  the  eggs  are  very 
numerous  they  seem  to  be  discharged  almost 
at  random  in  suitable  spots ;  but  moths  such 
as  Clisiocampa  ncustria  fasten  their  eggs 
round  the  stems  of  the  food-plant  in  a  very 
perfect  and  artistic  manner.  Butterflies 
seem  as  a  rule  to  prefer  to  oviposit  by  placing 
an  egg  here  and  there  rather  than  risk  many 
in  one  situation  ;  but  to  this  there  are  many 
conspicuous  exceptions  especially  in  the  cases 
where  the  larvae  live  gregariously,  as  in  the 
Yanessae.  Some  moths  cover  the  eggs  with 
fur  from  their  own  body,  which,  in  the  case 
of  certain  of  the  Eggers  (Lasiocampidae), 

FIG.  164.— Egg  of  Orange-   seems  to  have  a  special   supply  for   the   pur- 
tip  butterfly,  Euchlue 

cardamines,     magni-  pose.      ilie   period   that   intervenes    between 
tied.    </,  The  egg  of  deposition   and   hatching  of  the   eggs  varies 

natural  size  on  a  stalk. 

from  a  few  days  to  many  months.  There 
seems  to  be,  as  a  rule,  comparatively  little  power  of  extending  the 
period  of  latency  beyond  a  single  season  ;  though  certain  facts 
have  been  recorded  that  would  lead  us  to  believe  that  in 
Australia  eggs  may  last  over  the  proper  time  during  a  drought, 
and  be  hatched  as  soon  as  rain  falls. 

Larva. — The   young  condition  or  larva  of  the  Lepidopterous 
Insect    is    commonly    called    a    caterpillar.      It    is    a    somewhat 

it   was    sometimes    called 

1   Actu.  Ac.  German,  li.  18S7,  ]>.  238. 


worm-like    creature — in    old    English 


vi  LARVA  323 

palmer-worm — and  is  composed  of  a  head  and  thirteen  divisions 
or  segments  of  the  body ;  the  first  three  of  the  latter  are  called 
thoracic,  the  other  ten,  abdominal  segments  ;  in  most  caterpillars 
the  terminal  two  or  three  abdominal  segments  are  more  or  less 
run  together,  and  the  ninth  may  be  very  small,  so  that  the  true 
number  is  indistinct.  The  first  three  segments  bear  each,  on 
either  side,  a  short  limb,  ending  in  a  curved  spine ;  the  next 
two  (or  three  or  more)  segments  are  destitute  of  legs,  but  on 
some  of  the  following  divisions  another  kind  of  leg  of  a  more 
fleshy  character  appears,  while  the  body  is  terminated  by  a  pair 
of  these  thick  legs  of  somewhat  different  form.  The  front  legs 
are  usually  called  the  true  legs,  the  others  prolegs,  but  this  latter 
designation  is  a  most  unfortunate  one,  the  term  "  pro  "  being  in 
entomology  used  to  signify  anterior ;  it  is  therefore  better  to 
call  the  three  anterior  pairs  thoracic  legs,  and  the  others  abdominal 
feet, .  distinguishing  the  hind  pair  of  these  latter  as  claspers. 
There  is,  too,  an  unfortunate  discrepancy  amongst  entomologists  in 
their  manner  of  counting  the  body-segments,  some  count  the  head 
as  the  first  segment,  while  others  apply  this  term  to  the  first 
thoracic  segment.  The  latter  is  the  more  correct  course,  for,  as 
the  head  is  not  a  single  segment  it  should  not  be  called  such  in 
a  terminology  that  affects  to  be  morphologically  exact,  not  simply 
descriptive.  The  thoracic  legs  are  transversely  jointed  (Fig.  165, 
B),  but  this  is  not  the  case  with  the  abdominal  feet,  which  are 
usually  armed  beneath  with  a  circle,  or  with  rows,  of  little  hooks. 
The  thoracic  legs  are,  independent  of  their  form,  of  a  different 
nature  from  the  abdominal,  for  these  latter  disappear  subsequently, 
while  the  former  jjive  rise  to  the  les;s  of  the  imago.  The  number 

o  o  o 

of  thoracic  legs  is  always  six,  except  in  a  few  cases  where  there 
are  none  at  all ;  the  abdominal  feet  are  much  more  variable,  and 
exhibit  so  many  distinctions  that  we  cannot  here  attempt  to 
deal  with  them.  M.  Goossens  has  given  a  concise  and  interest- 
ing account  of  this  subject,1  and  Speyer  -  a  summary  of  the  variety 
in  number  and  position. 

The  anatomy  of  the  larva  is  simple  in  comparison  with  that 
of  the  perfect  Insect;  its  main  features  will  be  appreciated  from 
Fig.  165,  from  which  it  will  be  seen  that  the  stomach  is 
enormous,  and  the  silk-vessels  are  also  very  extensive.  There 
are  three  sets  of  glands  opening  by  canals  on  the  head,  viz.  the 

1  Ann.  Soc.  ent.  France,  1887,  pp.  384-404,  PI.  7.  "  Isis,  1845,  p.  835. 


LEPIDOPTERA 


CHAP. 


salivary  glands  proper,  which  open  into  the  cavity  of  the  mouth, 
one  close  to  the  base  of  each  mandible  ;  the  silk-glands,  which 
terminate  by  a  common  canal,  continued  externally  as  the  spin- 
neret ;  and  the  glands  of  Filippi  situate  in  the  head  itself,  and 
opening  into  the  ducts  of  the  silk-glands,  near  their  union 
into  a  common  duct.  It  should  be  recollected  that  Fig.  165 
does  not  indicate  all  the  details  of  the  anatomy ;  the  muscular 
system,  for  instance,  being  entirely  omitted,  though  there  are 
an  enormous  number  of  muscles  ;  these  however  are  not  very 
complex,  they  being  mostly  repetitions  in  the  successive  seg- 
ments.1 The  mouth -parts  are  very  different  from  those  of  the 

4-  d:j.        z  i 


FIG.  165. — A,  Section  of  male  caterpillar  of  Anosia  plcxippus — muscular  and  traclieal 
systems  and  fat-body  not  shown  :  I,  pro-,  II,  meso-,  III,  meta-thorax  ;  1-10, 
abdominal  segments  ;  b,  supra -oesophageal  ganglion  ;  c,  rectum  ;  d.v,  dorsal  vessel ; 
if-ff,  ganglia  of  ventral  chain  ;  h,  head  ;  /,  intestine  ;  iti.r,  Malpighian  tube  ;  n.c, 
nerve-cord  of  ventral  chain  ;  ue,  oesophagus  ;  «,  spinneret  ;  s.o.g,  infra-oesophageal 
ganglion  ;  nt,  stomach  ;  s.i;  silk-vessel  ;  t,  testis.  B,  One  of  the  jointed  prothoracic 
legs.  C,  An  abdominal  foot  with  its  hooks.  (After  Scudder  and  Burgess,  mag- 
nification about  -j.) 

perfect  Insect,  inasmuch  as  the  maxillae  and  labial  palpi,  which 
are  the  most  remarkable  structures  of  the  imago,  are  small,  and 
are  differently  constructed  in  the  caterpillar,  while  the  mandibles, 
which  are  the  largest  organs  of  the  caterpillar,  disappear  in  the 
adult.  The  little  organ  by  which  the  caterpillar  exudes  its  silk 
is  called  a  spinneret ;  according  to  Packard  it  is  a  "  homologue 
of  the  hypopharynx."  It  is  a  more  or  less  prominent  point  on 
the  middle  of  the  labium  (Fig.  1  66,  g}  and  sometimes  forms  a 
conspicuous  spine  projecting  downwards.  The  eyes  are  ex- 
tremely imperfect  organs,  consisting  merely  of  six,  in  some  cases 

1  For  anatomy  of  caterpillars  refer  to  Lyounet's  famous  work,  Trait£  anatomique 

de  la  c/teitilh'  qui  range  Ic  lois  de  saule,  La  Have,  1762. 


vi  LARVA  325 

fewer,  transparent,  somewhat  prominent,  little   spaces  placed   on 

each  side  of  the  lower  part  of  the  head ;   they  are  called  "  ocelli," 

by  Landois  "  ocelli  compositi."      Under  each   of  these    external 

facets    there    are    placed    percipient  « 

structures,  apparently  very  imperfect 

functionally,    the    caterpillar's    sight 

being  of  the  poorest  character.1      The 

spiracles   of  the  caterpillar  are   nine 

on  each  side,  placed  one  on  the  first 

thoracic  segment  and  one  on  each  of  ^/.      <-- 

/  */ 

the  first  eight  abdominal  segments  ;  . 

FIG.    166. — Front   view  of  head   of 

there    are    no   true    stigmata   on   the        a    caterpillar,    with   the   jaws 

second    and    third    thoracic    segments.          Partially   opened,      a     Labrum  ; 

o,     mandible  ;    c,     antenna  ;    tf, 
though    traces  Of    their    rudiments    Ol'  ocelli  ;  e,  maxilla  ;  /,  lingua  ;  g, 

vestiges  are  sometimes  visible.  sphmeret ;  7''  1:ihial  pal1'- 

In  the  caterpillar  there  are  no  traces  of  the  external  sexual 
organs,  so  that  the  two  sexes  cannot  be  distinguished  on  super- 
ficial inspection ;  it  was  however  long  ago  demonstrated  by 
Herold  2  that  the  ovaries  and  testes  exist  in  the  youngest  cater- 
pillars, and  undergo  a  certain  amount  of  growth  and  development 
in  the  larval  instars ;  the  most  important  feature  of  which  is 
that  the  testes  are  originally  separate  but  subsequently  coalesce 
in  the  middle  line  of  the  body,  and  become  enclosed  in  a  common 
capsule.  In  a  few  forms — especially  of  Liparidae — (Lymaiitriidae 
of  modern  authors) — the  caterpillars  are  said  to  be  of  different 
colours  in  the  two  sexes.  Most  of  what  is  known  on  this  point 
has  been  referred  to  by  Hatchett  Jackson.3 

The  SILK -GLANDS  of  Lepidoptera  are  of  great  interest  from  the 
physiological  point  of  view,  as  well  as  from  the  fact  that  they 
have  furnished  for  many  ages  one  of  the  most  beautiful  of  the 
adornments  made  use  of  by  our  own  species.  The  sericteria,  or 
vessels  that  secrete  silk,  are  of  simple  structure,  and  differ  greatly 
in  their  size  in  the  various  forms  of  the  Order;  they  sometimes 
become  of  great  length ;  in  the  Silk-worm  each  of  the  two 
vessels  is  nearly  five  times  as  long  as  the  body,  while  in 
Bombyx  yamamai  and  others,  even  this  is  exceeded.  They 

1  See  Plateau,  Bull.  Ac.  Belgique,  xv.  1888,  p.  28  ;  in  reference  to  structure  of 
ocelli,  Blanc,  Tete  du  Bombyx  mori  .  .  .  1891,  pp.  163,  etc.  ;  and  Landois  in 
Zcitsehr.  wiss.  Zool.  xvi.  1866,  p.  27-. 

-  Entvrickelungsgeschicfite  der  Schmetterlinge,  Cassel,  1815. 

3   Tr.  Linn.  Soc.  London,  Zool.  2nd  Ser.,  v.  1890,  pp.  147,  148. 


326  LEPIDOPTERA 


CHAP. 


grow  with  remarkable  rapidity,  being  in  the  young  silk-worm 
only  3  mm.  long,  in  the  adult  22  mm.  The  increase  in  weight  is 
still  more  remarkable  ;  when  the  silk-worm  is  thirty-one  days  old, 
the  sericteria  weigh  only  3  mgr.,  but  when  the  age  is  fifty  days 
their  weight  has  increased  to  541  mgr.,  being  then  |  of  the  whole 
weight  of  the  body.  In  the  pupa  they  undergo  a  gradual  atrophy, 
and  in  the  moth  they  are,  according  to  Helm,  no  longer  to  be 
found,  though  earlier  authors  were  of  a  contrary  opinion.1  Ac- 
cording to  Joseph,"  the  silk-vessels  begin  to  develop  at  an  ex- 
tremely early  age  of  the  embryo,  and  are  very  different  in  their 
nature  from  the  salivary  glands,  the  former  being  derivatives  of 
the  external  integument  (ectoderm),  while  the  salivary  glands 
belong  to  the  alimentary  system.  This  view  is  to  some  extent  con- 
firmed by  the  observations  of  Gilson  as  to  the  different  manner 
in  which  these  two  sets  of  glands  discharge  their  functions. 

The  chief  feature  in  the  anatomy  of  the  larva  is  the  great 
size  of  the  stomach.  There  is  a  very  short  oesophagus  and  crop  ; 
the  latter  becomes  enlarged,  spreading  out  so  as  to  form  the 
stomach,  a  great  sac  occupying  the  larger  part  of  the  body-cavity 
(Fig.  165).  On  the  hinder  end  of  this  sac  the  Malpighian  tubes 
open  ;  they  are  similar  in  their  disposition  to  those  of  the  imago  ; 
behind  the  stomach  the  canal  expands  into  two  successive,  short 
dilatations,  the  first  called  an  intestine,  the  second  a  rectum  ; 
they  are  connected  by  very  short  isthmuses.  The  dorsal  vessel 
is  a  simple,  slender  tube,  extending  from  the  eighth  abdominal 
segment  to  the  head.  The  main  nervous  system  consists  of 
supra-  and  infra -oesophageal  ganglia,  a  small  frontal  ganglion, 
and  a  ventral  chain  of  eleven  ganglia,  three  thoracic  and  eight 
abdominal,  the  last  of  these  latter  being  double.  The  sexual 
organs  are  quite  rudimentary,  and  the  passages  connected  with 
them  very  incompletely  developed. 

Pupa. — The  pupa,  which  is  one  of  the  most  remarkable  of 
the  instars  of  an  Insect's  life,  attains  its  highest  development  in 
Lepidoptera.  The  Lepidopterous  pupa  is  frequently  called  a  "  chry- 
salis," a  term  originally  ;ippli»'d  t<>  certain  metallic  butterfly  pupae. 
The  Lepidopterous  pupa  differs  from  that  of  other  Insects  in  the 
fact  that  its  outer  skin  forms  a  bard  shell,  all  the  appendages  of 

1  For  information  as  to  the  structure  and  function  of  the  silk-vessels,  refer  to 
Ifrhn,  Zci/sc/tr.  -wiss.  Zuol.  xxvi.  1876,  p.  434  ;  and  Gilson,  La  Cellule,  vi.  1800, 
p.  116.  -  Jahresbcr.  Schlcsisch.  Gcs.  Iviii.  1881,  p.  116. 


VI 


PUPA 


327 


the  body  being  glued  together  by  an  exudation  so  as  to  form  a 
single  continuous  outer  skin.  This  form  of  perfect  pupa  is  called 
"  pupa  obtecta."  The  obtected  pupa  is  exhibited  in  various  stages 
of  perfection  in  the  Lepidoptera  ;  the  maximum  of  perfection  is 
attained  by  the  pupae  of  such  butterflies  as  are  exposed  without 
protection  or  concealment ;  on  the  other  hand,  we  find  in  various 
small  moths  conditions  of  the  pupa  that  do  not  differ  in  any 
marked  manner  from  the  pupae  of  Insects  of  other  Orders. 
Moreover,  certain  Coleoptera  and  Diptera  exhibit  obtected  pupae 
of  a  more  or  less  perfect  kind.  Hence  the  pupa  obtecta  is  to  be 
considered  as  a  perfected  condition  that  exists  more  frequently 
in  the  Lepidoptera  than  in  other  Orders. 

The  pupa  has  no   orifices  to   the  alimentary  canal  or  sexual 

FIG.  167.— Section  of 
female  pupa  of 
Anosia  plexippus, 
3-4  days  old.  I, 
pro-,  II,  meso-,  III, 
meta-thorax  ;  1-9, 
abdominal  s  e  g- 
ments  ;  a,  anten- 
na(?)  ;  ac,  aortal 
chamber  ;  ay1  -  <nf\ 
abdominal  ganglia  ; 
a  g  I,  accessory 
glands  ;  ao,  aorta  ; 
br,  brain  ;  c,  colon  ; 

cj),  bursa  copulatrix  ;  cr,  cremaster  ;  fl,  first  femur  ;  fr,  food-reservoir  ;  /;,  dorsal  vessel  ; 

i,  part  of  intestine  ;  MI;  Malpighian  tube  ;  mx,  base  of  maxilla ;  oe,  oesophagus  ;  ov,  ovary  ; 

l)k,   pharynx;  sd,   salivary  duct;   sgl,  salivary  gland  ;  st,  stomach;   t\  first  tarsus;   tg, 

compound  thoracic  ganglion  ;  ts2,  is3,  second  and  third  tarsus..     (After  Scudder.) 

organs,  but  the  respiratory  openings  are  pervious.  It  has  no 
means  of  locomotion,  but  it  can  move  a  certain  number  of  the 
posterior  segments  (the  number  variable  according  to  kind).  In 
some  cases  it  is  provided  with  spines,  "  adminicula,"  by  means  of 
which,  aided  by  the  wriggling  movements  of  the  abdominal  seg- 
ments, considerable  changes  of  position  can  be  effected.  The 
pupae  of  the  genus  Micropteryx  apparently  use  the  legs  for 
locomotion,  as  do  the  pupae  of 'Trichoptera. 

The  study  of  the  pupa  of  Lepidoptera  is  less  advanced  than 
that  of  the  imago  and  larva,  between  which  it  is,  in  many  points 
of  structure,  intermediate.1  The  interior  of  the  pupa  contains  a 

1  The  student  will  find  important  information  as  to  the  varieties  of  external 
form  of  pupae  in  Dr.  T.  A.  Chapman's  writings  ;  see  especially  Tr.  cut.  Soc.  London, 
1893,  1894,  and  1896. 


iff 


mx. 


328 


LEPIDOPTERA 


CHAP. 


quantity  of  cream-like  matter,  including  the  results  of  histolysis 
—but  this,  as  well  as  the  condition  of  the  internal  organs,  differs 
much  according  to   whether   the  change   from   the   caterpillar  to 
the  moth  is  much  or  little  advanced. 

Many  pupae  are  protected  by  cocoons.  These  are  masses  of  silk 
—very  various  in  form — disposed  by  the  caterpillar  around  itself 
during  the  last  stage  of  its  existence.  Some  of  these  cocoons  are 
so  perfect  that  the  moth  has  considerable  difficulty  in  escaping 
when  the  metamorphosis  is  complete.  Various  devices  are  used 
for  the  purpose  of  emergence ;  the  Puss-moth  excretes  a  corrosive 
fluid,  containing  potassium  hydroxide,  and  then  protects  itself 
from  this  by  retaining  on  the  head  while  passing  through  it  a 
shield  formed  of  a  portion  of  the  pupa-skin.1  Lepidopterous  pupae 
usually  have  the  body  terminated  by  a  projection  of  very  various 
and  peculiar  form  called  "  cremaster."  In  certain  cases  these 
projections  are  used  for  the  suspension  of  the  pupa,  and  are  then 
frequently  provided  with  hooks  (Fig.  177,  C,  D).  In  other  cases 
the  cremaster  is  frequently  called  the  anal  armature  (Fig.  205,  B). 

The  development  of  the  wings 
of  Lepidoptera  has  recently  been 
much  studied.  It  has  been  known 
since  the  time  of  Lyonnet,  that 
the  rudiments  of  the  wings  exist 
inside  the  body  of  the  caterpillar 
when  it  is  nearly  adult.  Verson 
considers  that  he  has  detected  the 
rudiments  in  the  silk-worm  larva 
even  before  hatching,  and  he 
attributes  their  origin  to  a 
modification  of  form  of  those 

FlG.    168.— Wing -rudiments    of   Pieris  hypodemial       cells       that      OCCUpy 

brassicae.     A,   Rmlinieuts  of  a  wing  ,                               -,               ,-, 

before  the  first  moult  of  the  cater"  the      sPots      where      the      Spiracles 

pillar :   ce,  embryonic  cells  ;    ch,  ex-  of     the     Second     and     third     thor- 

ternal    cuticle ;    h.    hypodermis  ;    <>.  .    , 

opening   of    the   imagination;    tr,  acic    segments    might    be    looked 

trachea.     B,  posterior  wing-rudiment    for-        rt^   ^{\[    j^g    recollected    that 
of   full  -  grown    caterpillar  ;    b,    semi- 
circular pad;  c,  a  bundle  of  the  there    are    no    spiracles    on    these 

rolled  tracheae  ;  e,  envelope  ;  i,  pedi-    twQ     thoracic    segments     ill     Lepi- 

cel  ;  tr,  trachea.     (After  Goniu.) 

dopterous     larvae).        Gonm     has 
examined  the  wing-rudiments  in  the  caterpillar,  a  few  days  old,  of 

1  Latter,  Tr.  cut.  Soc.  London,  1895,  p.  399. 


vi  DEVELOPMENT  -  WINGS  -  NERVURES  329 

Pier  is  brassicae,1  and  finds  that  the  future  wing  is  then  indi- 
cated by  a  thickening  and  bagging  inwards  of  the  hypodermis, 
and  by  some  embryonic  cells  and  a  trachea  in  close  relation  with 
this  mass  (Fig.  168,  A).  The  structure  grows  so  as  to  form  a  sac 
projecting  to  the  interior  of  the  body,  connected  with  the  body- 
wall  by  a  pedicel,  and  penetrated  by  a  trachea  forming  branches 
consisting  of  rolled  and  contorted  small  tracheae  (Fig.  '168,  B). 
If  the  body  -wall  be  dissected  off  the  caterpillar  immediately 
before  pupation  the  wings  appear  in  crumpled  form,  as  shown 

in   Fig.  169.      This  fact  was  known 

a        a 

to  the  older   entomologists,  and  gave        sti 
rise   to    the    idea    that    the    butterfly 
could  be  detected  in  a  caterpillar  by 
merely  stripping  off  the  integument. 

The  exact  mode  by  which  the 
wings  become  external  at  the  time 
of  appearance  of  the  chrysalis  is  not 
ascertained  ;  but  it  would  appear  from  p"  p.-" 

Goilill's    Observations     that    it    is    not    FIG.  169.—  Anterior  parts  of  a  cater- 

by  a  process  of  evagination,  but  by        Pillar  of  p-  brassieae,  the  body- 

.    '  wall   having  beeii  dissected   oft, 

destruction    Ot    the    hypodermiS    lying          immediately     before     pupation. 

outside  the  wing.      However  this  may        a\  a'>  Anterior  and  posterior 

wings  ;  st  7,  first  spiracle  ;  p,  p  , 
be,  it    is    Well    kllOWll    that,    when    the  second    and   third   legs.      (After 


caterpillar's  skin  is  finally  shed  and 
the  chrysalis  appears,  the  wings  are  free,  external  appendages, 
and  soon  become  fastened  down  to  the  body  by  an  exudation 
that  hardens  so  as  to  form  the  shell  of  the  chrysalis. 

Scales  and  nervures.  —  Before  tracing  the  further  develop- 
ment it  will  be  well  to  discuss  the  structure  of  the  scales  and 
nervures  that  form  such  important  features  in  the  Lepidopterous 
wing. 

If  a  section  be  made  of  the  perfect  wing  of  a  Lepidopteron, 
it  is  found  that  the  two  layers  or  walls  of  the  wing  are  firmly 
held  together  by  material  irregularly  arranged,  in  a  somewhat 
columnar  manner.  The  thickness  of  the  wing  is  much  greater 
where  the  section  cuts  through  a  nervure  (Fig.  1VO,  A).  The 
nervures  apparently  differ  as  to  the  structures  found  in  them. 
Spuler  observed  in  a  nervure  of  Triphaena  pronuba,  a  body  having 
in  section  a  considerable  diameter,  that  he  considered  to  be  a 

1  Bull.  Soc.  Vaudoise,  xxx.  1894,  No.  115. 


330 


LEPIDOPTERA 


CHAP. 


trachea,  and  also  a  "  wing-rib  "  and  blood-cells.  He  remarks  that 
even  in  nervures,  perfectly  formed  as  to  their  chitinous  parts, 
either  wing-rib  or  trachea  or  both  may  be  absent.1  Schaffer 2 
was  unable  to  find  any  tracheae  in  the  completed  wings  he 
examined,  and  he  states  that  the 
matrix  of  the  tracheae  and  even 
their  inner  linings  disappear.  The 
wing-ribs  were,  however,  found  by 
him  to  be  present  (Fig.  170,  A 
and  B). 

The  scales  that  form  so  con- 
spicuous a  feature  in  Lepidoptera 
exist  in  surprising  profusion,  and 


B 


FIG.  170. — Structure  of  wing  of  imago.  A, 
Transverse  section  of  basal  portion  of  wing 
[of  Vanessa  ?]  containing  a  nervure  :  <; 
cuticle  ;  ft;  wing-rib  ;  //,  wall  of  nervure 
("  Grunilmembran  ")  ;  //,  hypodermis  ;  p, 
connecting  columns  :  r,  lumen  of  nervure  ;  B, 
section  of  a  rib  ;  b,  one  of  the  chitinous  pro- 
jections ;  sir,  central  rod.  (After  Schafl'er.) 


Fiu.  171.  — Scales  of  male  Lepidoptera. 
A,  Scale  from  upper  surface  of 
Eccres  /•<niii//t/"x ;  B,  from  upper 
surface  of  Pieris  m/Hic  :  C,  from 
inner  side  of  fold  of  inner  margin 
of  hind  wing  of  Laertias phihnor  ; 
D,  one  of  the  cover-scales  from  the 
costal  androconinm  of  Eudamiis 
jirofeus  ;  E,  F,  G,  scales  from  andro- 
coniunt  of  Thorybes  pylades.  (After 
Scudder). 


are  of  the  most  varied  forms.  They  may  be  briefly  described 
as  delicate,  chitinous  bags  ;  in  the  completed  state  these  bags 
are  flattened,  so  as  to  bring  the  sides  quite,  or  very  nearly, 
together.  Their  colour  is  due  to  contained  pigments,  or  to  stria- 
tion  of  the  exposed  surface  of  the  scale ;  the  latter  condition 
1  ZdtKclir.  n-iss.  Zwl .  liii.  1892,  p.  623.  2  Zool.  Jahrl.  Annt.  iii.  1889,  p.  (346. 


VI 


SCALES 


331 


A. 

Socket  holding  the  stalk  in  Galleria 
mellonella ;  B,  insertion  of  the  scale 
of  Polyommatus  phloeas.  b,  Base  of 
scale  ;  •;•,  holding-ring  ;  w,  surface  of 
wing.  (After  Spuler.) 


giving  rise  to  metallic  "  interference-colours."  The  walls  of  the 
scales  are  themselves,  in  some  cases,  tinted  with  pigment.  It  is 
said  that  some  of  the  scales  contain  air,  and  that  the  glistening 

O  O 

whiteness  of  certain  scales  is  due  to  this.     The  exposed  surface  of 

the  scale  usually  differs  from  the 

surface  that  is  pressed   down   on 

the  wing  in  being  delicately  and 

regularly     striated ;    the    colours 

of  the  upper  and  under  surfaces 

of    a    scale    may    also    be    quite 

different.      Scales   are   essentially 

of   the   nature   of   hairs,  and    all 

the  transitions  between  hairs  and  FIG>    179.  —  insertion   of   scales. 

true   scales   may  be  found  on  the 

wings  of  certain  Lepidoptera  that 

baar   both    hairs    and   scales,  e.g. 

Ithomia.      It  has  been  calculated 

that  there  are  a  million  and  a  half  of  scales  on  the  wings  of  an 

individual   of    the    genus  Moiylio.      The  scales  are   arranged   on 

the  wing  in  an  overlapping  manner,  somewhat  like  slates  on  the 

roof  of  a  house.      Each  scale  has  a  short  stalk,  and  is  maintained 

in  position  by  the  stalk  fitting  into  a  cavity  in  a  projection  of 

the  wing-membrane  (Fig.  172). 

Androconia.  - -The  males  of  numerous  butterflies  possess 
scales  peculiar  in  kind  and  various  in  arrangement.  They  may 
be  either  irregularly  scattered  over  the  wring,  or  they  may  form 
very  complex  definite  structures  (Fig.  173).  They  were  formerly 
called  "  plumules,"  but  Scudder  has  replaced  this  name  by  the 
better  one,  "  androconia."  The  function  of  the  androconia  is 
still  obscure.  An  odour  is  believed  to  be  connected  with  them. 
Thomas  supposes  l  that  these  scales  are  hollow  tubes  in  connec- 
tion with  glands  at  their  bases,  and  that  matter  secreted  by  the 
glands  passes  through  the  scales  and  becomes  diffused.  In 
nearly  all  Lepidoptera  it  is  the  male  that  seeks  the  female  ;  if 
therefore  odorous  scales  were  present  in  one  sex  only  we  should 
have  supposed  that  this  would  have  been  the  female  rather  than 
the  male.  As,  however,  the  reverse  is  the  case,  the  function  of 
the  androconia  is  supposed  to  be  that  of  charming  the  female. 
Scudder  considers  that  the  covering  part  of  the  androconial 

1  Amer.  Natural.,  xxvii.  1893,  p.  1018. 


332 


LEPIDOPTERA 


CHAP. 


structures  is  sometimes  ornamental.  As  a  rule,  however,  the 
•'  brands "  of  male  Lepidoptera  detract  from  their  beauty  to 
our  eyes. 


FIG.  173. — A,  section  of  part  of  wing  showing  the  complex  androconia  of  Thanaos  tages, 
a  Skipper  butterfly.  The  turning  over  of  the  costal  margin  of  the  wing  is  in  this 
case  part  of  the  arrangement.  «,  Upper  covering-scales  attached  to  the  costal 
portion  of  the  under  surface  of  the  wing  ;  b,  edge  of  costal  margin  of  the  wing  ; 
c,  costal  nervure  with  its  scales  ;  d,  field  of  the  wing  next  the  costal  nervure,  bearing 
stunted  scales  ;  e,  the  androconia  proper,  or  male  scales  ;  /,  posterior  covering 
scales  ;  g,  lumen  of  the  costal  nervure  :  B,  a  portion  of  the  costal  area  flattened 
out  and  seen  from  above  ;  lettering  as  before  :  C,  section  of  audroconium  on  the 
second  nervure  of  Argynnis  paphia.  (After  Aurivillius.) 

Resuming  our  consideration  of  the  development  of  the  wings, 
we  may  remark  that  the  history  of  the  changes  during  the 
pupal  state  is  still  imperfect.  By  the  changes  of  relative  size 
of  the  thoracic  segments  the  hind  wing  is  brought  to  lie  under 
the  anterior  one  (i.e.  between  it  and  the  body),  so  that  in  the 
newly  formed  pupa  the  arrangement  is  that  shown  in  Fig.  1 74. 
The  wings  are  two  sacs  filled  with  material  surrounding  peri- 
tracheal  spaces  in  which  run  tracheae.  The  subsequent  history 
of  the  tracheae  is  very  obscure,  and  contrary  opinions  have  been 
expressed  as  to  their  growth  and  disappearance.  We  have 
alluded  to  the  fact  that  in  some  nervures  tracheae  are  present, 
while  in  others  they  are  absent;  so  that  it  is  quite  possible  that 


VI 


WING-DEVELOPMENT 


ao, 


the  histories  of  the  formation  of  the  nervures  and  of  their 
relation  to  tracheae  are  different  in  various  Lepidoptera.  This 
conclusion  is  rendered  more  probable  by  the  statement  of  Corn- 
stock  and  JSTeedharn,1  that  in  some  Insects  the  "  peritracheal 
spaces  "  that  mark  out  the  position  of 
the  future  nervures  are  destitute  of 
tracheae.  Gonin  thinks  the  nervures 
are  derived  from  the  sheaths  of  the 
peritracheal  spaces,  and  a  review  of  all 
the  facts  suggests  that  the  tracheae 
have  only  a  secondary  relation  to  the 
nervures,  and  that  the  view  that  a 
study  of  the  pupal  tracheae  may  be 
looked  on  as  a  study  of  the  pre- 
liminary state  of  the  nervures  is  not 
sufficiently  exact.  It  is,  however, 
probable  that  in  Lepidoptera  the 
pupal  tracheae  play  an  important 
though  not  a  primary  part  in  the 
formation  of  the  nervures  ;  possibly 
this  may  be  by  setting  up  changes  in 
the  cells  near  them  by  means  of  the 
air  they  supply.  Semper  long  ago 
discovered  hypodermal  cylinders  tra- 
versed by  a  string  (Fig.  170,  B), 
placed  near  the  tracheae  in  the 
pupa,2  It  appears  probable  that  the  "wing -ribs"  found  in 
the  nervures  (Fig.  170,  Afr  and  B)  are  the  final  state  of  these 
cylinders,  but  the  origin  and  import  of  the  cylinders  are  still 
unknown. 

The  formation  of  the  scales  of  the  wing  commences  very 
early — apparently  soon  after  the  casting  of  the  larval  skin- 
though  the  completion  of  the  scales  and  their  pigmentation  is 
delayed  to  a  late  period  of  the  pupal  life.  The  scales  are  formed 
by  special  cells  of  the  hypodermis  that  are  placed  deeper  in  the 
interior  of  'the  wing  than  the  other  hypodermal  cells.  Each 
scale  is  formed  by  one  cell,  and  protrudes  through  the  over- 
lying hypodermis ;  the  membrane  into  which  the  scales  are 
inserted  is  a  subsequently  developed  structure,  and  the  beautiful 

1  Aincr.  Natural.,  xxxii.  1898.  p.  256.        -  Zeitschr.  u-iss.  Zool.  viii.  1857,  p.  326. 


chrysalis  of  Pieris  brassicae, 
showing  the  position  and  struc- 
ture of  the  wings,  hanging 
from  one  side  of  the  body. 
aa,  Anterior  wing  ;  up,  pos- 
terior wing  ;  e,  e,  peritracheal 
spaces  ;  t,  t,  tracheae.  (After 
Gouin.) 


LEPIDOPTERA 


CHAP. 


articulation  of  the  scale  with  the  wing  takes  place  by  a  division 
of  the  stalk  of  the  scale  where  it  is  encompassed  by  the  mem- 
brane. Semper  was  not  able  to  show  that  the  scale-forming 
cells  are  certainly  hypodermal  cells,  but  this  has  since  been 
demonstrated  by  Schaffer,  who  also  shows  that  each  of  the  cells 
contains  an  excretory  vesicle. 

Very  little  is  positively  known  as  to  the  development  of  the 
colour  in  the  wing-scales.  It  has  been  pointed  out  by  Hopkins  l 
that  in  some  cases  the  colours  are  of  the  nature  of  unites ;  that 
is,  of  excretory  matter  of  the  kind  that  usually  passes  from  the 
body  by  direct  channels,  and  in  the  case  of  Lepidoptera,  by  the 
Malpighian  tubes.  Miss  IsTewbigin  suggests  that  the  organic 
pigments  used  in  scale -coloration  will  be  found  to  be  of  two 


"i;L    B 


FIG.  175.— Early  condition  of  scales  and  nervures.  (After  Semper.)  A,  Section  of 
portion  of  \viug  of  pupa  of  N//////M:  /li/n/xtr/  ;  n,  basal  membrane  with  trachea 
beneath  it  ;  c,  scale-forming  cell  ;  </,  early  state  of  a  scale  ;  e,  e,  more  advanced 
stages  ;  /,  hypodermal  cells.  B,  part  of  a  cellular  cylinder  that  excretes  the 
nervure  [or  more  probably  the  rib  or  "  Rippe  "  of  Schaffer;  cf.  Fig.  170,  B]  ;  b. 
epithelial  [hypodermal]  cells  ;  a,  central  string  [supposed  by  Semper  to  be  a  nerve]. 

kinds,  urates  and  melanins,  the  urates  being  derivatives  from  nitro- 
genous, the  melanins  from  carbonaceous,  matters.2  Marchal,  who 
has  devoted  a  great  deal  of  attention  to  the  study  of  the  Malpi- 
ghian tubes,  informs  us  that  the  siibdermal  pigments  of  cater- 
pillars are  fretpiiently  in  large  part  deposits  of  urates,  and  he  is 
of  opinion  that,  the  function  of  the  Malpighian  tubes  being 
arrested  at  certain  periods  of  the  metamorphosis,  elimination  of 
the  matter  they  separate  when  functionally  active  then  takes 
place  in  a  variety  of  other  ways.3  A  similar  condition  as  to 
the  melanin-pigments  and  the  respiratory  functions  appears  also 

1   Pit II  Trans.  186  B,  1896,  No.  15.  -  Xatwal  Science,  viii.  1896,  p.  94. 

s  Bull.  Soc.  ent.  France,  1896,  p.  257. 


vi  WING-PATTERN SENSITIVENESS  335 

probable.  The  scales  when  first  formed  are  pallid,  and  the  physi- 
ology of  their  pigmentation  is  not  fully  ascertained ;  it  is,  how- 
ever, known  that  when  the  scales  are  pallid  the  hypodermis  is 
either  pigmented  or  in  close  contact  with  pigmentary  matter, 
and  that  as  the  scales  become  coloured  this  pigmentation  of  the 
hypodermis  diminishes ;  so  that  it  is  clear  that  the  colour  of 
the  scales  is  obtained  from  matter  in  the  interior  of  the  develop- 
ing wing,  and  probably  by  the  agency  of  the  hypodermis. 

The  pattern  on  the  wings  of  Lepidoptera  is  formed  before 
the  emergence  from  the  pupa.  In  the  Tortoiseshell  butterfly, 
according  to  Schaffer,  it  commences  to  appear  about  the  ninth 
day  of  the  pupal  life,  and  the  pattern  is  completed  about  the 
eleventh  or  twelfth  day.  He  also  states  that  the  process  varies 
in  its  rapidity,  and  this,  he  thinks,  may  depend  on  the  previous 
condition  of  the  larva.  According  to  Buckell  the  pupa  of 
Ncmeoliius  lucina  is  sufficiently  transparent  to  allow  the  develop- 
ment of  the  colour  of  the  imago  to  be  watched.  He  says  that 
the  coloration  occurred  first  in  front;  that  its  entire  production 
occupied  less  than  twenty-fonr  hours,  and  only  commenced  about 
forty-eight  hours  before  the  imago  emerged.1  When  the  butter- 
fly leaves  the  pupal  skin  the  wings  are  soft,  crumpled  sacs,  of 
comparatively  small  size,  but,  as  everyone  knows,  they  rapidly 
expand  and  become  rigid ;  the  physiology  of  this  process  is 
apparently  still  unknown. 

A  great  deal  of  evidence,  both  direct  and  indirect,  has 
accumulated  showing  that  the  organisation  of  many  Lepidoptera 
is  excessively  sensitive,  so  that  slight  changes  of  condition  pro- 
duce remarkable  results ;  and  it  has  also  been  shown  that  in  the 
early  part  of  the  life  this  sensitiveness  is  especially  great  at  the 
period  of  ecdysis.  Numerous  butterflies  produce  more  than  one 
generation  a  year,  and  sometimes  the  generations  are  so  different 
that  they  have  passed  current  with  entomologists  as  distinct 
species.  The  phenomena  of  this  character  are  styled  "  seasonal 
variations "  or  "  seasonal  dimorphism."  It  has,  however,  been 
shown  that,  by  careful  management,  the  eggs  of  a  generation  (say 
form  «.)  may  be  made  to  produce  form  a,  whereas  in  the  usual 
course  of  nature  they  would  produce  form  1>.  A  very  remarkable 
condition  is  exhibited  by  the  North  American  Papilio  ajax.  There 
are  three  forms  of  the  species,  known  as  P.  ajax,  P.  telamonides, 

1  Ent.  Record,  vi.  1895,  p.  258. 


336  LEPIDOPTERA  CHAP. 

and  P.  marcellus.  It  is  uncertain  how  many  generations  there 
may  be  in  one  year  of  this  species,  as  the  length  of  the  life- 
cycle  varies  greatly  according  to  circumstances.  But  in  West 
Virginia  all  the  butterflies  of  this  species  that  emerge  from  the 
chrysalis  before  the  middle  of  April  are  the  form  marcellus  ; 
those  produced  between  the  middle  of  April  and  the  end  of  May 
are  telamonides ;  while  those  that  appear  after  this  are  ajax. 
P.  telamonides  is  not,  however,  the  offspring  of  marcellus,  for  both 
forms  emerge  from  pupae  that  have  passed  through  the  winter 
(and  are  the  offspring  of  ajax'),  those  that  emerge  early  being 
marcellus,  those  that  appear  later  telamonides. 

In  various  parts  of  Asia  and  Africa  the  butterflies  produced 
during  the  wet  season  differ  more  or  less  markedly  from  those  of 
the  same  species  produced  during  the  dry  season.  These  are 
called  "  wet  "  and  "  dry  season  "  forms.  Their  aetiology  has  not 
been  investigated,  this  discovery  being  comparatively  recent. 

Turning  to  the  early  life  we  find  that  some  larvae  vary  in 
colour,  and  that  this  variation  is  sometimes  of  a  definite  char- 
acter, the  larva  being  one  of  two  different  colours — green  or 
brown.  In  other  cases  the  variation  of  the  species  is  less 
definitely  dimorphic,  a  considerable  range  of  variation  being 
exhibited  by  the  species.  In  tracing  the  life-histories  of  Lepi- 
dopterous  larvae  it  is  not  rare  to  find  species  in  which  the  larva 
abruptly  changes  its  form  and  colour  in  the  middle  of  its  life, 
and  so  completely  that  no  one  would  believe  the  identity  of  the 
individual  in  the  two  successive  conditions  had  it  not  been 
shown  by  direct  observation ;  in  these  cases  the  change  in 
appearance  is  usually  associated  with  a  change  in  habits,  the 
larva  being,  perhaps,  a  miner  in  leaves  in  its  first  stages,  and  an 
external  feeder  subsequently.  In  the  case  of  the  larval  variation 
we  have  alluded  to  above,  it  is  understood  that  there  is  no 
marked  change  of  habits.  1'oulton  has  shown *  that  it  is  not 
infrequent  for  some  of  these  latter  kinds  of  variable  larvae  to 
change  colour  during  life,  and  he  considers  that  light  or  conditions 
of  illumination,  that  he  speaks  of  as  "  phytoscopic,"  are  the  in- 
ducing causes.  Great  difference  is,  however,  exhibited  according 
to  species,  some  variable  species  not  being  so  amenable  to  these 
influences  as  others  are.  In  dimorphic  forms  the  change  was 
observed  to  take  place  at  a  moult,  the  larva  changing  its  skin 

1   Tnuts.  cut.  SOL:  London,  1892,  p.  293,  etc. 


vt  SENSITIVENESS — MIMICRY  337 

and  appearing  of  another  colour.  In  some  cases  the  result  of 
the  change  was  to  bring  the  colour  of  the  larva  into  harmony 
with  its  surroundings,  but  in  others  it  was  not  so.  During  the 
final  stage  many  larvae  are  susceptible,  the  result  being  made 
evident  only  when  the  pupa  is  disclosed.  Variably  coloured 
pupae  of  certain  species  of  butterflies  have  long  been  knowrn,  and 
it  has  been  shown  that  some  of  the  varieties  can  be  induced  by 
changing  the  surroundings.  The  result  of  the  changes  is  in 
certain  cases  correspondence  between  the  colour  of  the  individual 
and  its  surroundings.  In  the  case  of  other  species  having  pupae 
of  variable  colour,  the  colour  of  the  pupa  is  without  relation  to, 
or  harmony  with,  the  surroundings. 

Experiments  have  been  made  on  pupae  by  Merrifield  and 
others,  with  the  result  of  showing  that  by  changes  of  tempera- 
ture applied  at  certain  moments  some  of  the  colours  or  marks  of 
the  butterfly  that  will  emerge  can  be  altered. 

It  is  found  that  in  certain  localities  the  colour  of  various 
kinds  of  butterflies  more  or  less  agrees,  while  it  differs  from 
that  of  the  same  butterflies  found  in  other  localities.  Thus 
Weir  speaks  of  a  duskiness  common  to  various  butterflies  in 
Java,  and  calls  it  "phaeism"  ;  and  Bates  states  that  in  the  Amazon 
valley  numerous  species  of  butterflies  vary  in  a  similar  manner, 
as  regards  colour,  in  a  locality.  This  phenomenon  is  now  called 
"  homoeochromatism,"  and  is  supposed  to  be  due  to  the  effect  of 
local  conditions  on  a  susceptible  organisation,  though  there  is  no 
experimental  evidence  of  this. 

Mimicry. — There  are  many  cases  in  Lepidoptera  of  species 
that  depart  more  or  less  strongly  in  appearance  from  those  forms 
to  which  they  are  considered  to  be  allied,  and  at  the  same  time 
resemble  more  or  less  closely  species  to  which  they  are  less  allied. 
This  phenomenon  is  called  mimicry.1  Usually  the  resembling 
forms  are  actually  associated  during  life.  Bates,  wrho  observed 
this  phenomenon  in  the  Amazon  valley,  thought  that  it  might 
be  accounted  for  by  the  advantage  resulting  to  the  exceptionally 
coloured  forms  from  the  resemblance ; 2  it  being  assumed  that 
these  were  unprotected,  while  the  forms  they  resembled  were 

1  The  term  mimicry  is  sometimes  used  in  a  wider  sense  ;  but  we  think  it  better 
to  limit  it  to  its  original  meaning.  The  word  is  a  most  unfortunate  one,  being 
both  inadequate  and  inaccurate. 

'•  Trans.  Linn,  Soc.  xxiii.  1862,  p.  507. 
VOL.   VI 


338  LEPIDOPTERA  CHAP. 

believed  to  be  specially  protected  by  nauseous  odours  or  taste. 
It  was,  in  fact,  thought  that  the  destroying  enemies  were 
deceived  by  the  resemblance  into  supposing  that  the  forms  that 
were  in  reality  edible  were  inedible.  This  subject  has  been 
greatly  discussed,  and  in  the  course  of  the  discussion  numerous 
cases  that  could  not  be  accounted  for  by  Bates's  hypothesis  have 
been  revealed.  One  of  these  is  the  fact  that  resemblances  of  the 
kind  alluded  to  very  frequently  occur  amongst  inedible  forms. 
This  also  has  been  thought  to  be  accounted  for  by  a  supposed 
advantage  to  the  Insects ;  it  being  argued  that  a  certain  number 
of  "  protected  "  forms  are  destroyed  by  enemies  the  instincts  of 
which  are  faulty,  and  which  therefore  always  require  to  learn  by 
individual  experience  that  a  certain  sort  of  colour  is  associated 
with  a  nasty  taste.  The  next  step  of  the  argument  is  that  it 
will  be  an  advantage  to  a  protected  butterfly  to  form  part  of 
a  large  association  of  forms  having  one  coloration,  because 
the  ignorant  enemies  will  more  easily  learn  the  association  of  a 
certain  form  of  coloration  with  nastiness ;  moreover  such  destruc- 
tion as  does  occur  will  be  distributed  over  a  larger  number  of 
species,  so  that  each  species  of  a  large,  similarly  coloured,  inedible 
association  will  have  a  less  number  of  its  individuals  destroyed. 
It  is  scarcely  a  matter  for  surprise  that  many  naturalists  are 
very  sceptical  as  to  these  explanations  ;  especially  as  the  pheno- 
mena are  supposed  to  have  occurred  in  the  past,  so  that  they 
cannot  be  directly  verified  or  disproved.  It  has  not,  however, 
been  found,  as  a  matter  of  fact,  that  even  unprotected  butterflies 
are  much  destroyed  in  the  perfect  state  by  birds.  Moreover,  in 
endeavouring  to  realise  the  steps  of  the  process  of  development 
of  the  resemblance,  we  meet  with  the  difficulty  that  the  amount 
of  resemblance  to  the  model  that  is  assumed  to  be  efficient  at 
one  step  of  the  development,  and  to  bring  safety,  is  at  the  next 
step  supposed  to  be  inefficient  and  to  involve  destruction.  In 
other  words,  while  analysis  of  the  explanation  shows  that  it 
postulates  a  peculiar  and  well-directed  discriminative  power, 
and  a  persistent  selection  on  the  part  of  the  birds,  observation 
leads  to  the  belief  that  birds  have  been  but  little  concerned  in 
the  matter.  If  we  add  to  this  that  there  is  no  sufficient  evidence 
that  the  species  now  similar  were  ever  dissimilar  (as  it  is  sup- 
posed they  were  by  the  advocates  of  the  hypothesis),  we  think 
it  is  clear  that  the  explanation  from  our  point  of  view  is  of  but 


vi  MIMICRY CLASSIFICATION  339 

little  importance.1  The  comparatively  simple,  hypothetical 
explanation,  originally  promulgated  by  Bates,  is  sometimes  called 
Batesian  mimicry ;  while  the  "  inedible  association  "  hypothesis 
is  termed  Miillerian  mimicry. 

There  is  one  branch  of  the  subject  of  mimicry  that  we  think 
of  great  interest.  This  is  the  resemblance  between  Insects  of 
different  Orders ;  or  between  Insects  of  the  same  Order,  but  be- 
longing to  groups  that  are  essentially  different  in  form  and 
appearance.  It  is  not  infrequent  for  beetles  to  resemble  Hymen- 
optera,  and  it  is  still  more  frequent  for  Lepidoptera  to  resemble 
Hymenoptera,  and  that  not  only  in  colour  and  form,  but  also  in 
movements  and  attitude.  Druce  says  :  "  Many  of  the  species  of 
Zygaenidae  are  the  most  wonderful  of  all  the  moths  ;  in  some 
cases  they  so  closely  resemble  Hymenoptera  that  at  first  sight  it 
is  almost  impossible  to  determine  to  which  Order  they  belong." 
W.  Miiller  says:  "The  little  Lepidoptera  of  the  family  Glaucopides, 
that  are  so  like  certain  wasps  as  to  completely  deceive  us,  have 
when  alive  exactly  the  same  manner  of  holding  their  wings,  the 
same  restless  movements,  the  same  irregular  flight  as  a  wasp." 
Seitz  and  others  record  a  case  in  which  a  Brazilian  Macroglossa 
exactly  resembles  a  humming-bird,  in  company  with  which  it 
flies  ;  and  the  same  naturalist  also  tells  us 4  of  a  Skipper  butterfly 
that  greatly  resembles  a  grasshopper  of  the  genus  Tettix,  and  that 
moreover  makes  movements  like  the  jumping  of  grasshoppers. 
In  most  of  these  cases  the  probabilities  of  either  original 
similarity,  arrested  evolution,  or  the  action  of  similar  conditions 
are  excluded :  and  the  hypothesis  of  the  influence,  by  some  means 
or  other,  of  one  organism  on  another  is  strongly  suggested. 

The  classification  of  Lepidoptera  was  said  by  Latreille  a 
century  ago  to  be  a  reproach  to  entomologists.  Since  that  time 
an  enormous  number  of  new  species  and  genera  have  been 
described,  but  only  recently  has  much  advance  been  made  in 

1  A  summary  of  the  chief  aspects  of  the  question  is  contained  in  Beddard's 
Animal  Coloration,  London,  1892.  An  account  of  the  subject  with  numerous  illus- 
trations has  been  given  by  Haase,  "  Untersuchungen  iiber  die  Mimicry,"  Bill. 
ZonJ.  iii.  1893,  Heft  viii.  Those  who  wish  to  see  the  case  as  stated  by  an  advocate 
may  refer  to  Professor  Poulton's  work,  The  Colours  of  Animals  (International 
Scientific  Series),  Ixviii.  London,  1890. 

-  P.  Zool.  Sue.  London,  1883,  p.  372. 

3  Kosmos,  xix.  1886,  p.  353.     The  Insects  alluded  to  by  both  these  naturalists 
are  now,  we  believe,  placed  in  the  Family  Syntomidae  (see  p.  388). 

4  Stctt.  cut.  Zdt.  li.  1891,  p.  264  ;  and  Ivi.  1895,  p.  234. 


340 


LEPIDOPTERA 


CHAP. 


the  way  of  improvement  of  classification.  The  progress  made 
has  been  limited  to  a  better  comprehension  and  definition  of  the 
families.  The  nervuration  of  the  wings  is  the  character  most 
in  vogue  for  this  purpose.  As  regards  the  larger  groups,  and 
Phylogeny,  there  is  a  general  opinion  prevalent  to  the  effect  that 
Micropterygidae,  Eriocephalidae  and  Hepialidae  are  in  a  com- 
paratively primitive  condition,  but  as  to  the  relations  of  these 
families  one  with  the  other,  or  with  other  Lepidoptera,  there  is  a 
wide  difference  of  opinion. 

The  primary  divisions   of  the  family  most  often  met   with   in 
literature   are  : — either   Ehopalocera  (  =  butterflies^  and   Hetero- 


FlG.  176.— Clubs  of  butterflies' 
antennae.  Terminal  portions 
of  antenna  of,  1,  Pier  is  bras- 

siaif  ;  '_',  >'///.!•  infernalis ;  3, 
Hetstiu  ill  en  (sub-family  Dan- 
aicle.s)  ;  4,  Eudamus  proteus, 
ami  5,  Lii/HH-lini-i'x  tinnnas 
(Hesperiidae).  (Alter  Bchatz 
and  Sc  mliler.) 


cera  ( =  moths.) ;  or  Macrolepidoptera  and  Microlepidoptera ; 
the  Macrolepidoptera  including  the  butterflies  and  large  moths, 
the  Microlepidoptera  being  limited  to  the  families  Tineidae 
(now  itself  in  process  of  division  into  numerous  families)  and 
Tortricidae ;  some  entomologists  including  also  Pvr;ilidac,  Ptero- 
phoridae  and  Orneodidae  in  Microlepidoptera.  The  division  of  all 
Lepidoptera  into  two  series  is  merely  a  temporary  device  necessi- 
tated by  imperfect  acquaintance  with  morphology.  The  division 
into  Macro-  and  Micro-  lepidoptera  is  entirely  uuscu'iitilir. 

Series  1.  Rhopalocera  or  Butterflies. — Antennae  knobbed  at  the  tip  or 
thickened  a  little  before  the  tip,  without  pectinations,  projecting 
processes,  or  conspicuous  arrangements  of  cilia.  Hind  wings  with- 
out a  frenulum,  but  with  the  costal  nervure  strongly  curved  at  the 
base  (Fig.  161,  II,  B). 

Series  II.  7/r/rrwrm  or  Cloths. — Antennae  various  in  form,  only  rarely 
knobbed  at  the  tip,  and  in  such  cases  a  frenulum  present.  In  the 
large  majority  a  riviiulimi  is  present,  and  the  costal  nervure  of  the 
hind-wing  is  either  but  little  a  relied  at  the  base  (as  in  Fig.  KM. 
I,  B)  or  it,  has  a  large  area  between  it  and  the  front  margin; 
but  in  certain  families  the  hind  wing  is  formed  much  as  in 
Rhopalocera. 


vi  BUTTERFLIES  34! 

It  may  be  inferred  from  these  definitions  that  the  distinc- 
tion between  the  two  snb-Orders  is  neither  sharply  defined  nor  of 
great  importance.  The  club  of  the  antenna  of  the  Rhopalocera 
exhibits  considerable  variety  in  form  (Fig.  17G).1  Butterflies 
are  as  a  rule  diurnal  in  their  activity  and  moths  nocturnal ;  but 
in  the  tropics  there  are  numerous  Heterocera  that  are  diurnal, 
and  many  of  these  resemble  butterflies  not  only  in  colour  but 
even  in  the  shapes  of  their  wings. 


Series  I.   Rhopalocera.     Butterflies. 

Classification  and  Families  of  Butterflies. — Although 
considerable  unanimity  exists  as  to  the  natural  groups  of  butter- 
flies, there  is  much  diversity  of  opinion  as  to  what  divisions  are 
of  equivalent  value — some  treating  as  sub-families  groups  that 
others  call  families — and  as  to  the  way  the  families  should  be 
combined.  There  is,  however,  a  general  agreement  that  the 
Hesperiidae  are  the  most  distinct  of  the  families,  and  E.  Renter 
considers  them  a  distinct  sub-Order  with  the  name  Grypocera.2 

Four  categories  may  be  readily  distinguished,  as  follows, 
viz.  :— 

1.  The  majority  of  butterflies  ;  having  the  first  pair  of  legs  more  or  less  strik- 

ingly different  from  the  other  pairs  ;  frequently  very  much  smaller 
and  not  used  as  legs  ;  when  not  very  small,  then  differing  according 
to  sex  of  the  same  species,  being  smaller  in  the  male  than  in 
the  female  ;  the  part  most  peculiar  is  the  tarsus,  which  is  modified 
in  various  manners,  but  in  the  males  of  this  great  series  is  always 
destitute  of  its  natural  form  of  a  succession  of  simple  joints  five  in 
number.  There  is  no  pad  on  the  front  tibia, 

Fam.  NYMPHALIDAE,  ERYCINIDAE,  LYCAENIDAE. 
[The  distinctions  between  these  three  families  are  found  in  the 
amount   and    kind    of  the    abortion   of   the   front  legs ;    for 
definition  refer  to  the  heading  of  each  of  the  families.] 

2.  The   front   legs  are   in   general  form   like   the  other  pairs ;    their  tibiae 

have  no  pads;  the  claws  of  all  the  feet  are  bifid,  and  there  is  an 
empodiuui  in  connection  with  them.  Fam.  PIERIDAE. 

1  For  an  account  of  the  antenna  of  butterflies,  see  Jordan,  J\~oi:  Zool.  v.  1898, 
pp.  37-1-415. 

2  Haase  first  proposed  the  name  Netrocera  (Deutsclie  cut.  Zeit.  Lcp.  iv.   1891, 
p.   1)  for  Hesperiidae,  as  a  division  distinct  from  all  other  butterflies  ;    Karsch 
replaced  the  name  in  the  following  year  by  Grypoceva,  because  Netrocera  is  the 
name  of  a  genus. 


342  LEPIDOPTERA  CHAP. 

3.  The   front   legs  are   like  the  other  pairs  ;    their   tibiae   however  possess 

pads  ;  the  claws  are  large,  not  bifid,  and  there  is  no  empodium  ; 
the  metanotum  is  completely  exposed  at  the  base  of  the  abdomen. 

Fam.   PAPILIONIDAE. 

4.  The  front  legs  are    like   the  other  pairs  ;    their   tibiae   however  possess 

pads  ;  the  claws  are  small,  toothed  at  the  base,  and  there  is  an 
empodium  ;  the  metanotum  is  concealed  by  the  prolonged  and 
overhanging  mesonotum.  Fam.  HESPERIIDAE. 

The  relations  between  the  families  Erycinidae,  Lycaenidae, 
and  Nymphalidae  are  very  intimate.  All  these  have  the  front 
legs  more  or  less  modified,  and  the  distinctions  between  the 
families  depend  almost  entirely  on  generalisations  as  to  these 
modifications.  These  facts  have  led  Scudder  to  associate  the 
Lycaenidae  and  Erycinidae  in  one  group,  which  he  terms 
'  Eurales."  It  is  however  difficult  to  go  so  far  and  no  farther  : 
for  the  relations  between  both  divisions  of  Eurales  and  the 
Nymphalidae  are  considerable.  "NVe  shall  subsequently  find  that 
the  genus  Libytliea  is  by  many  retained  as  a  separate  family, 
chiefly  because  it  is  difficult  to  decide  whether  it  should  be 
placed  in  Erycinidae  or  in  Nymphalidae.  Hence  it  is  difficult  to 
see  in  this  enormous  complex  of  seven  or  eight  thousand  species 
more  than  a  single  great  Nymphalo-Lycaenid  alliance.  The 
forms  really  cognate  in  the  three  families  are  however  so  few, 
and  the  number  of  species  in  the  whole  is  so  very  large,  that  it 
is  a  matter  of  great  convenience  in  practice  to  keep  the  three 
families  apart.  It  is  sufficient  for  larger  purposes  to  bear  in 
mind  their  intimate  connexions. 

The  Papilionidae  and  Pieridae  are  treated  by  many  as  two 
sub-divisions  of  one  group.  But  we  have  not  been  able  to  find 
any  justification  for  this  in  the  existence  of  forms  with  connect- 
ing characters.  Indeed  it  would,  from  this  point  of  view, 
appear  that  the  Pieridae  are  more  closely  connected  with  the 
Lycaenidae  and  Erycinidae  than  they  are  with  Papilionidae ; 
in  one  important  character,  the  absence  of  the  pad  of  the  front 
tibia,  the  Nyinphalo-Lycaenids  and  the  Pierids  agree.  It  has 
also  been  frequently  suggested  that  the  Papilionidae  (in  the 
larger  sense  just  mentioned)  might  be  associated  with  the 
Hesperiidae.  But  no  satisfactory  links  have  been  brought  to 
light;  and  if  one  of  the  more  lowly  Hesj>eriids,  such  as  Tlianaos, 
be  compared  with  one  of  the  lower  Papilionidae,  such  as 
Parnassius,  very  little  approximation  can  be  perceived. 


vi  BUTTERFLIES  343 

It  appears,  therefore,  at  present  that  Hesperiidae,  Papi- 
lionidae,  Pieridae,  and  the  Nymphalo-Lycaenid  complex  are 
naturally  distinct.  But  in  the  following  review  of  the  families 
and  sub-families  of  butterflies,  we  shall,  in  accordance  with  the 
views  of  the  majority  of  Lepidopterists,  treat  the  Lycaenidae 
and  Erycinidae  as  families  distinct  from  both  Nymphalidae  and 
Pieridae.1 

The  number  of  described  species  of  butterflies  is  probably 
about  13,000;  but  the  list  is  at  present  far  from  complete; 
forms  of  the  largest  size  and  most  striking  appearance  being  still 
occasionally  discovered.  Forty  years  ago  the  number  known 
was  not  more  than  one-third  or  one-fourth  of  what  it  is  at 
present,  and  a  crowd  of  novelties  of  the  less  conspicuous  kinds  is 
brought  to  light  every  year.  Hence  it  is  not  too  much  to  antici- 
pate that  30,000,  or  even  40,000  forms  may  be  acquired  if 
entomologists  continue'  to  seek  them  with  the  enthusiasm  and 
industry  that  have  been  manifested  of  late.  On  the  other 
hand,  the  species  of  Rhopalocera  seem  to  be  peculiarly  liable  to 
dimorphic,  to  seasonal  and  to  local  variation ;  so  that  it  is 
possible  that  ultimately  the  number  of  true  species — that  is, 
forms  that  do  not  breed  together  actually  or  by  means  of  inter- 
mediates, morphological  or  chronological — may  have  to  be  con- 
siderably reduced. 

In  Britain  we  have  a  list  of  only  sixty-eight  native  butter- 
flies, and  some  even  of  these  are  things  of  the  past,  \vhile  others 
are  only  too  certainly  disappearing.  New  Zealand  is  still 
poorer,  possessing  only  eighteen ;  and  this  number  will  prob- 
ably be  but  little  increased  by  future  discoveries.  South 
America  is  the  richest  part  of  the  world,  and  Wallace  informs  us 
that  600  species  of  butterflies  could,  forty  years  ago,  be  found 
in  the  environs  of  the  city  of  Para. 

Fam.  1.  Nymphalidae. — The  front  pair  of  legs  much  reduced 
in  size  in  each  sex,  their  tarsi  in  the  male  with  but  one  joint, 

'•  The  literature  of  butterflies  has  become  extremely  extensive.  The  following 
works  contain  information  as  to  general  questions  :  1,  Scudder's  Butterflies  of  Neio 
England,  a  beautifully  illustrated  work  completed  in  1889,  and  replete  with 
interesting  discussions.  2,  Staudinger,  Schatz  and  Rober,  Exotischc  Tag/alter, 
in  three  folio  volumes  (Fiirth,  1884-1887),  with  illustrations  of  exotic  butterflies 
and  a  detailed  sketch  of  their  characters.  3,  Enzio  Renter,  "Tiber  die  Palpen 
der  Rhopaloceren,"  in  Acta  Soc.  Sci.  Fenn.  xxii.  1896,  treating  fully  of  classifica- 
tion and  phylogeny. 


344 


LEriDOPTERA 


CHAP. 


though  in  the  female  there  are  usually  five  hut  without  any  claws. 
Pupa  xiixjii'iided  l>y  the  tail  so  as  to  hang  down  freely.  AVe 
include  in  this  family  several  sub -families  treated  by  some 
taxonomists  as  families  ;  in  this  respect  we  follow  Bates,  whose 
arrangement l  still  remains  the  basis  of  butterfly  classification. 
With  this  extension  the  Nymphalidae  is  the  most  important  of 
the  families  of  butterflies,  and  includes  upwards  of  250  genera, 
and  between  4000  and  5000  species.  There  are  eight  sub- 
families. 

It  is  in  Nymphalidae  that  the  act  of  pupation  reaches  its 
acme  of  complication  and  perfection  ;  the  pupae  hang  suspended 
by  the  tail,  and  the  cremaster,  that  is  the  process  at  the  end 

of  the  body,  bears  highly- 
developed  hooks  (Fig.  177, 
C,  D).  The  variety  in 
form  of  the  chrysalids  is 
extraordinary;  humps  or 
processes  often  project 
from  the  body,  making 
the  Insect  a  fantastic 
object ;  the  strange  ap- 
pearance is  frequently  in- 

FIG.  177.— Pupa  of  the  Purple  Emperor  butterfly,  Creased      by      patches      like 
Apatura    in        New  Forest.     A,   Lateral,    B,         M  ^  j        j 

dorsal  aspect  ;  C,   enlarged  view  of  cremaster  ° 

with  the  suspensory  hook  ;   D,   one  hook  still  Various    parts  of    the    body, 

more  enlarged.  -r,  IT         j      -i  ,-1 

It    is     believed    that    the 


I 


term  chrysalid  was  first  suggested  by  these  golden  pupae. 
The  Purple  Emperor,  Apatura  iris,  differs  strikingly  in  the  pupa- 
as  well  as  in  the  larva- stage  from  all  our  other  Nymphalids ;  it 
is  of  green  colour,  very  broad  along  the  sides,  but  narrow  on 
the  dorsal  and  ventral  aspects  (Pig.  177).  The  skin  of  this 
pupa  is  less  hard  than  usual,  and  the  pupa  seems  to  be  of  a 
very  delicate  constitution.  The  Purple  Emperor,  like  some  of 
the  Satyrides  as  well  as  some  of  its  more  immediate  congeners, 
hibernates  in  our  climate  as  a  partially  grown  larva  and  passes 
consequently  only  a  very  brief  period  of  its  existence  in  the 
form  of  a  pupa. 

Sub-Fam.    1.    Danaides. — Front    wing    with    inner-margin 

1  Journal  of  Entomology,  i.    1862,  p.  218  :  for  early  instars  of  South  American 
Nymphalidae  sue  JM tiller,  Zoo  1.  Jahrl.  Syst.  i.  1886,  p.  117. 


vi  RHOPALOCERA DANAIDES  345 


(submedian)  nervure,  with  a  short  fork  at  the  base.  Cell  of  hind 
i/'iug  dosed.  Front  foot  of  the  female  ending  in  a  corrugate 
knob.  Caterpillars  smooth,  provided  with  a  feio  long  fie  shy  pro- 
cesses. The  claws  are  in  a  variable  state,  being  sometimes  simple, 
as  in  Papilionidae,  sometimes  with  an  empodium,  apparently  of 
an  imperfect  kind.  The  Danaides  are  usually  large  Insects  with 
an  imperfect  style  of  ornament  and  colour  ;  they  have  a  great 
deal  of  black  or  very  dark  scaling,  and  in  some  Euploea  this 
is  agreeably  relieved  by  a  violet  or  purple  suffusion,  and  these 
are  really  fine  Insects.  Usually  there  are  large  pale  spaces,  of 
some  neutral  indefinite  tint,  on  which  black  blotches  are  dis- 
tributed in  a  striking  but  inartistic  manner.  In  many  of  the 
species  the  markings  are  almost  spot  for  spot  the  same  on  the 
upper  and  under  sides.  About  seven  genera  and  250  species  are 
recognised.  Danaides  occur  in  all  the  warmer  parts  of  the 
world,  but  are  most  numerous  in  the  Eastern  tropics.  In  Europe 
the  family  is  represented  only  by  an  Asiatic  and  African  species, 
Limnas  chrysippus,  that  has  extended  its  range  to  Greece. 
Besides  this  another  species,  Anosia  erippus,  Or.  (unfortunately 
also  called  Anosia  menippe,  Hb.,  and  Danais  archippus  or  even  I). 
plexippus)  has  in  the  last  two  or  three  decades  extended  its 
range  to  various  islands  and  distant  localities,  concomitantly,  it 
is  believed,  with  an  extension  of  the  distribution  of  its  food-plant, 
Asdepias.  This  Insect  has  several  times  been  taken  in  this 
country,  and  may  probably  be  a  natural  immigrant.  It  is  a 
common  butterfly  in  North  America,  where  it  is  called  the 
Monarch.1 

Some,  at  least,  of  the  Danaides  are  unpleasant  to  birds  in 
odour  or  in  taste,  or  both.  Among  them  there  occur,  according 
to  Moore 2  and  others,  numerous  cases  of  resemblance  between 
forms  that  are  thus  protected.  It  is  possible  that  the  odour 
and  taste  are  of  some  value  to  the  Insects ; 3  as,  however,  butter- 
flies of  any  kind  appear  to  be  but  rarely  attacked  in  the  imago- 
state  by  birds,  and  as  their  chief  enemies  are  parasitic  Insects 
that  attack  the  larval  instar,  it  is  impossible  to  consider  this 
protection  of  such  prime  importance  to  the  species  as  many 
theorists  assume  it  to  be. 

1  This  is  the  subject  of  Scudder's  Life  of  a  Butterfly,  1893. 

2  P.  Zoul.  Soc.  London,  1883,  p.  205. 

3  Finn,  J.  Asiat.  Soc.  Bengal,  Ixvi.  1896,  p.  528  ;  Ixvii.  1897,  p.  213. 


346  LEPIDOPTERA  CHAP. 

Sub-Fam.  2.  Ithomiides. — Differs  from.  Danaides  ly  the 
female  front  foot  having  a  true,  though  somewhat  abbreviate 
fi'/'sus.  The  caterpiUcrs  have  no  long  processes.  There  has  been 
considerable  difference  of  opinion  as  to  this  division  of  butter- 
flies. It  is  the  family  Neotropidae  of  Schatz,  the  Mechanitidae 
of  Berg ;  also  the  "  Danaioid  Heliconiidae  "  of  several  previous 
writers,  except  that  Itunci  and  Lycorea  do  not  belong  here 
but  to  Danaides.  Godman  and  Salvin  treat  it  as  a  group 
of  the  Danaid  sub -family.  The  Ithomiides  are  peculiar  to 
tropical  America,  where  some  20  or  30  genera  and  about  500 

species  have  been  discovered. 
^/  ^-^^  There  is  considerable  variety 
amongst  them.  Ithomia  and 
Hy  in  i  a  if  is  are  remarkable  for  the 
small  area  of  their  wings,  which 
bear  remarkably  few  scales,  these 

ornaments   being    in    many    cases 
FIG.  1/S. — Itfiomia  pusio.     Brazil. 

limited    to     narrow    bands    along 

the  margins  of  the  wings,  and  a  mark  extending  along  the 
discocellular  nervule.  Wallace  says  they  prefer  the  shades  of 
the  forest  and  flit,  almost  invisible,  among  the  dark  foliage. 
Many  of  these  species  have  the  hind-wings  differently  veined 
in  the  two  sexes  on  the  anterior  part,  in  connection  with  the 
existence  in  the  male  of  peculiar  fine  hairs,  placed  near  the 
costal  and  subcostal  veins.  Tithorea  and  other  forms  are,  how- 
ever, heavily  scaled  insects  of  stronger  build,  their  colours  usually 
being  black,  tawny-red  or  brown,  yellow,  and  white.  In  the 
sub-fam.  Danaides,  according  to  Fritz  Miiller,  the  male  has  scent- 
tufts  at  the  extremity  of  the  abdomen,  whereas  in  Ithomiides 
analogous  structures  exist  on  the  upper  side  of  the  hind-wing. 
Ithomiides  have  various  colour-resemblances  with  members  of 
the  Heliconiides  and  Pieridae ;  Tithorea  has  colour  analogues  in 
Heliconius,  and  Ithomia  in  Dismorpliia  (formerly  called  Leptalis). 
Crowds  of  individuals  of  certain  species  of  Ithomia  are  occasion- 
ally met  with,  and  mixed  with  them  there  are  found  a  small 
number  of  examples  of  Dism»r/>// ia  coloured  like  thrmst-hrs. 
They  arc  placed  by  Haase  in  his  category  of  secondary  models. 
Belt  states  that  some  Ithomiides  are  distasteful  to  monkeys  and 
spiders,  but  are  destroyed  by  Fossorial  Hymenoptera,  which  use 
the  butterflies  as  food  for  their  young  ;  and  he  also  says  that 


vi  RHOPALOCERA — 1THOMIIDES SATYRIDES  347 

they  are  very  wary  when  the  wasp  is  near,  and  rise  off  their 
perches  into  the  air,  as  if  aware  that  the  wasp  will  not  then 
endeavour  to  seize  them.  "  Much  information  is  given  about 
the  habits  by  Bates  in  the  paper  in  which  he  first  propounded 
the  "  theory  of  mimicry."  The  larvae  are  said  to  live  on 
Solanaceae. 

The  genus  Hamadryas  is  placed  by  some  writers  in  Danaides, 
by  others  in  Ithomiides ;  and  Haase  has  proposed  to  make  it  the 
group  "  Palaeotropinae."  The  species  are  small,  black  and  white 
Insects,  somewhat  like  Pierids.  They  are  apparently  hardy 
Insects,  and  are  abundant  in  certain  parts  of  the  Austro-Malay 


region. 


Sub-Fam.  3.  Satyrides. — Palpi  strongly  pressed  tor/ether,  set 
in  front  with  long,  stiff  hairs.  Front  wings  frequently  with  one 
or  more  of  the  nervures  swollen  or  'bladder-like  at  the  base  of  the 
wing.  Cells  of  both  wings  closed.  Caterpillar  thickest  at  the 
middle,  the  hind  end  of  the  body  bijid.  Pupa  generally  suspended 
by  the  cretnastcr,  without  girth:  but  sometimes  terrestrial.  This 
is  a  very  extensive  group,  consisting  of  upwards  of  1000  species. 
The  Insects  are  usually  of  small  size,  of  various  shades  of  brown 
or  greyish  colours,  with  circular  or  ringed  marks  on  the  under 
sides  of  the  wings.  It  is  found  all  over  the  world,  and  is  well 
represented  in  Europe;  our  Meadow-browns,  Heaths,  and  Marbled- 
whites,  as  well  as  the  great  genus  Erelria  of  the  highlands  and 
mountains  belonging  to  it.  Most  of  these  Insects  have  but 
feeble  powers  of  flight,  and  rise  but  little  from  the  surface  of  the 
ground.  The  caterpillars  live  on  various  grasses.  They  are 
usually  green  or  brown,  destitute  of  armature,  and  a  good  deal 
like  the  caterpillars  of  Noctuid  moths,  but  the  hind  end  of  the 
body  is  thinner  and  divided  to  form  twTo  corners,  while  the  head 
is  more  or  less  free,  or  outstanding.  The  pupae  are  of  great 
interest,  inasmuch  as  in  a  few  cases  they  do  not  suspend  them- 
selves in  any  way,  but  lie  on  the  ground  ;  sometimes  in  a  very 
feeble  cocoon  or  cell.  There  are  no  cremasteral  hooks.  The 
pupae  of  the  Grayling  butterfly,  Hipparchia  semelc,  has  been 
found  in  loose  soil  a  quarter  of  an  inch  below  the  surface.  The 
chrysalis  of  the  Scotch  Argus,  Erebia  aethiops,  was  found  by 
Mr.  Buckler  to  be  neither  suspended  nor  attached,  but  placed 
in  a  perpendicular  position,  head  upwards,  amongst  the  grass. 

1    Trans.  Linn.  Soc.  xxiii,  1862,  p.  495. 


348  LEPIDOPTERA  CHAP. 

In  the  majority  of  cases  the  pupa  is,  however,  suspended 
as  is  usual  in  Nymphalidae.  Nothing  is  known  as  to  the 
nature  of  the  peculiar  inflation  of  the  bases  of  the  nervures  of 
the  front  wings ;  it  is  well  shown  in  our  common  species  of 
Coenonympha]  this  character  is  not,  however,  constant  through- 
out the  family.  There  is  in  South  America  a  very  remarkable 
group  of  Satyrides  consisting  of  the  genera  Cithaerias  and 
Haetcm,  in  which  the  wings  are  very  delicate  and  transparent, 
bearing  on  the  greater  part  of  their  area  remote  fine  hairs  instead 
of  scales ;  there  are  nevertheless  some  scaled  patches  about  the 
margins,  and  one  or  more  of  the  ringed  marks  characteristic  of 
the  Satyrides  ;  while  in  some  species  the  distal  portions  of  the 
hind  wings  are  tinted  with  carmine,  The  species  of  the  genus 
Pierella  connect  these  transparent  Satyrids  with  the  more 
ordinary  forms.  According  to  Wallace  the  habits  of  these 
fairy-like  forms  are  those  characteristic  of  the  family  in  general. 
The  genus  Elymnias  has  been  separated  by  some  authorities  ;is 
a  sub-family,  or  even  as  a  family,  Elymniidae,  chiefly  on  the 
ground  of  a  slight  peculiarity  in  the  termination  of  the  branches 
of  the  veins  at  the  outer  angle  of  the  front  wings.  The  Elymnias 
are  said  to  be  of  a  mimetic  nature,  having  a  greater  or  less 
resemblance  to  butterflies  of  various  other  divisions  ;  there  is 
also  a  considerable  difference  in  appearance  between  their  own 
sexes.  The  larva  of  E.  undularis  is  known  ;  it  is  of  the  form 
usual  in  Satyrides,  and  lives  on  the  palm  Corypha.  About 
50  species,  ranging  from  India  to  Australia,  with  two  in  Africa, 
are  known  of  this  interesting  group. 

Sub-Fam.  4.  Morphides. — There  is  no  cell  on  the  hind  ?r/////, 
the  discocellular  ncrrulc  Icing  absent  (Fig.  1 6 1,  II.  B).  Caterpillars 
smooth  or  spiny,  with  the  extremity  of  the  u<><ly  divided ;  frequently 
gretjitrioiix.  These  Insects  have  become  notorious  from  the  extra- 
ordinary brilliancy  of  blue  colour  exhibited  by  the  upper  surface  of 
the  wings  of  the  typical  genus  Morpho.  The  species  ofMorpho  are 
all  Insects  of  large  size,  but  with  wings  enormous  in  proportion 
to  the  body  ;  this  latter  part  is  carried  in  a  sort  of  cradle  formed 
by  the  inner  parts  of  the  margins  of  the  hind  wings.  Although 
an  arrangement  of  this  kind  is  seen  in  numerous  other  butter- 
flies, yet  there  is  perhaps  none  in  which  it  is  carried  to  quite 
such  a  pitch  of  perfection  as  it  is  in  MorpJio,  where,  on  the 
under  surface  no  part  of  the  body  behind  the  posterior  legs  can 


vi  RHOPALOCERA MORPHIDES BRASSOLIDES  349 


be  seen.  There  are  only  about  100  species  of  Morphides,  and 
50  of  these  are  included  in  Morplio,  which  is  peculiar  to  tropical 
and  sub-tropical  America  ;  the  other  half  of  the  family  is  divided 
among  ten  or  twelve  genera,  found  in  the  Indo-Malay  region  ; 
there  being  none  in  Africa.  The  eastern  Morphides,  though 
fine  Insects,  are  not  to  be  compared,  either  in  size  or  brilliancy, 
with  their  American  allies.  The  species  of  Morplio  are  ap- 
parently found  only  in  the  great  forests  of  South  America, 
where  they  are  far  from  rare  ;  some  have  a  flapping  and  undulat- 
ing flight,  straight  onwards  along  the  alleys  of  the  forest,  and 
near  the  ground  ;  others  are  never  seen  except  steadily  gliding 
with  outstretched  wings  from  20  to  100  feet  above  the  ground, 
where  they  move  across  sunny  spaces  between  the  crowns  of  the 
taller  trees ;  the  low  -  flyers  settle  frequently  on  the  ground 
to  suck  the  juices  from  fallen  fruit,  but  the  members  of  the 
other  section  never  descend  to  the  ground.  As  regards  the 
caterpillars,  "\V.  M tiller  tells  us l  that  the  spines  they  are  armed 
with  break  off,  and  enter  the  skin,  if  the  creatures  are  carelessly 
handled.  Four  of  the  five  species  known  to  him  are  conspicu- 
ously coloured  with  black,  red,  yellow  and  white.  The  individuals 
are  gregarious.  The  larvae  of  M.  achilles  sit  in  companies,  often 
of  more  than  100  individuals,  on  trunks  of  trees,  and  so  form  a 
conspicuous  patch.  The  caterpillars  of  M.  epistrophis  hang  to- 
gether as  red  clumps  on  the  twigs  of  their  food-plants.  Hence 
it  appears  that  in  this  genus  wre  have  an  exception  to  the  rule 
that  night-feeding  caterpillars  rest  in  a  hidden  manner  during 
the  day. 

Sub-Fain.  5.  Brassolides. — Large  butterflies,  with  the  cell  of 
the  hind  wing  'closed,  and  usually  with  a.  small  adjoining  predis- 
coidal  cell.  Larva  not  very  s-piny  ;  thinner  at  the  two  ends,  the  tail 
l>ijid,  the  head  perpendicular  and  margined  with  spines.  This 
small  sub-family  includes  less  than  100  species  arranged  in  about 
eight  genera,  all  South  American.  They  have  the  very  unusual 
habit  of  resting  during  the  day  like  moths,  becoming  active  only 
late  in  the  afternoon.  They  are  truly  noble  Insects ;  although 
not  possessed  of  the  brilliant  colours  of  Morplio,  they  are 
adorned,  especially  on  the  under  surface,  with  intricate  lines 
and  shades  most  harmoniously  combined,  while  the  upper  surface 
is  frequently  suffused  with  blue  or  purple.  This  sub-family 

1  Kosmos,  xix.  1886,  p.  355. 


350 


LEPIDOPTERA 


CHAP. 


attains  its  highest  perfection  in  the 
genus  Caligo  ;  they  are  enormous 
Insects,  and  some  of  them  not  rare. 
The  larva  of  C.  eurylochu.s  (Fig.  179) 
during  early  life  is  green,  and  sits 
on  the  leaf  of  a  Masa,  but  after  the 
third  moult  it  becomes  brown  and 

£     hides  itself  among  the  dry  leaves.      It 
is   common   in   the  gardens   of  Eio  de 

£     Janeiro,  where  its  pupae  are  found   on 

•~     the    walls,    like    those    of    our    white 

^     butterflies  here. 

Sub  -  Fam.    6.    Acraeides.  -  -  Sul- 

x      median  ncrrure  of  fore-  wl  mjs  not  forked 
at  the  lase  ;   the   -median  without  spur. 

Q 

•§      Cells  closed.    Palpi  in  section  cylindric, 
£     sparingly  set  with  Ixdrs.      Larva  armed 
-r     with    Iranched    spines.       A    somewhat 
•2     monotonous  and  uninteresting  division  : 
r_;     the  size   is  moderate  or  small,  and   the 
colours   not   artistic,   but  consisting  of 
ill-arranged    spots ;   the    under   side   of 
the   hind  wings  very  frequently  cliver- 
"|     sifted    by    numerous    line-like    marks, 
radiately  arranged,  and  giving  place  at 
the    base    to   a    few   spots.      There   are 
about  200  species  known,  of  which  the 
majority    are    African ;    there    are    but 
few  Oriental  or  South  American  species. 
Some    authorities     consider     there     is 
o     only    one    Eastern    genus,    but    others 
prefer  to  adopt  seven  or  eight  divisions. 
£     Aliicna   is   now    placed    in   Lycaenidae, 
though     until    recently     it    was     con- 
sidered to  belong  here.      The  females  of 
some  species  possess  an  abdominal  pouch 
somewhat  similar  to  that  of  Parnassius. 
The    members    of    this    suit-family 
are   considered  to   be   of  the  protected 
kind. 


vi  RHOPALOCERA HELICONIIDES  3  5  I 

Sub-Fam.  7.  Heliconiides. — S/ibmedian  nervure  of  front  wing 
not  forked  ;  median  with  a  short  spar  near  the  base.  Cell  of  hind 
wing  dosed  by  a  perfect  nervule.  Palpi  compressed,  witli  scales  at 
the  sides,  in  front  covered  with  hairs.  Male  with  an  elongate 
n  n jointed,  female  witli  a  four-jointed,  front  tarsus.  Caterpillars  set 
with  lr«  ni'iu'd,  spines.  This  family  is  peculiar  to  tropical  America 
and  consists  of  only  two  genera,  Heliconius  and  Eueides,  with 
about  150  species;  but  it  is  one  of  the  most  characteristic  of  the 
South  American  groups  of  Butterflies.  It  is  very  closely  allied  to 
the  Nymphalides,  especially  to  the  genera  Metamorpha  and  Colaenis, 
but  is  readily  distinguished  by  the  perfectly-formed  nervules  that 
close  the  wing-cells.  The  wings  are  longer  and  narrower  than 
in  Nymphalides,  and  the  colour,  though  exhibiting  much  diver- 
sity, is  on  the  whole  similar  to  that  of  the  heavily-scaled  forms 
of  Ithomiides  of  the  genera  Titliorea,  Melinaea,  Melanitis  ;  there 
being  in  several  cases  a  great  resemblance  between  species  of  the 
two  groups.  A  frequent  feature  in  one  group  of  Heliconius  is 
that  the  hind  wing  bears  a  patch  of  red  prolonged  outwards  by 
angular  radiating  marks.  The  individuals  of  certain  species — If. 
melpomene  and  H.  rhea — are  known  to  execute  concerted  dances, 
rising  and  falling  in  the  air  like  gnats ;  when  some  of  them 
withdraw  from  the  concert  others  fill  their  places.  H.  erato 
exhibits  the  very  rare  condition  of  trichroism,  the  hind  wings 
being  either  red,  blue,  or  green.  Schatz  states  that  the  different 
forms  have  been  reared  from  a  single  brood  of  larvae.  The  cater- 
pillars of  Heliconiides  live  on  Passiflorae,  and  are  said  to  be  very 
similar  to  our  European  ^4;v/?/ /mis-caterpillars.  The  chrysalids 
are  very  spinous.  "We  may  here  remark  that  considerable  con- 
fusion exists  in  entomological  literature  in  consequence  of  Itho- 
miides having  been  formerly  included  in  this  sub-family ;  for 
remarks  formerly  made  as  to  "  Heliconiides,"  but  that  really 
referred  only  to  Ithomiides,  have  been  interpreted  as  referring 
to  Heliconiides  of  the  present  system. 

The  Heliconiides  seem  remarkably  plastic  as  regards  colour, 
and  are  therefore  exponents  of  "  homoeochromatism."  Bates 
says,  as  regards  them :  "  In  tropical  South  America  a  numerous 
series  of  gaily-coloured  butterflies  and  moths,  of  very  differ- 
ent families,  which  occur  in  abundance  in  almost  every  locality 

»/  i/ 

a  naturalist  may  visit,  are  found  all   to   change   their   hues  and 
markings  together,  as  if  by  the  touch  of  an  enchanter's  wand,  at 


352  LEPIDOPTERA  CHAP. 

every  few  hundred  miles,  the  distances  being  shorter  near  the 
eastern  slopes  of  the  Andes  than  nearer  the  Atlantic.  So  close 
is  the  accord  of  some  half-dozen  species  (of  widely  different  genera) 
in  each  change,  that  he  had  seen  them  in  large  collections  classed 
and  named  respectively  as  one  species."  Many  of  them  are 
believed  to  be  permeated  by  nauseous  fluids,  or  to  possess  glands 
producing  ill-smelling  secretions. 

Sub-Fam.  8.  Nymphalides. — Cells,  of  both  front  and  hind 
/'•/////,  citjicr  closed  only  l:nj  imperfect  transverse  nervules  or  entirely 
open.  Fi-onl  tiii'xiis  of  the  male  unjointed  and  without  sjiin.cs, 
of  the  female  four-  or  fire-jointed.  Caterpillar  either  spincd 
or  smooth;  in  the  latter  case  the  head  nn»'c.  or  lexs  stromjly 
horned  or  seined,  mid  the  apex  of  the  body  bijid.  This  sub- 
family is  specially  characterised  by  the  open  cells  of  the 
wings  ;  the  discocellulars,  even  when  present,  being  frequently 
so  imperfect  as  to  escape  all  but  the  most  careful  observa- 
tion. The  Nymphalides  include  upwards  of  150  genera  and 
2000  species.  The  divisions  having  smooth  larvae  are  separated 
by  Kirby  '2  and  others  as  a  distinct  sub-family  (Apaturides).  In 
Britain,  as  in  most  other  parts  of  the  world,  Nymphalides  is  the 
predominant  group  of  butterflies.  We  have  eighteen  species,  am<  >i  ig 
which  are  included  the  Fritillaries,  Admirals,  Purple  Emperor,  and 
the  various  Vanessa — Peacock,  Camber  well  Beauty,  Red  Admiral, 
Tortoise-shells,  and  Painted  Lady.  All  have  spined  caterpillars 
except  the  Emperor.  In  the  temperate  regions  of  the  northern 
hemisphere  Vanessa  may  be  considered  the  dominant  butter- 
flies, they  being  very  numerous  in  individuals,  though  not  in 
species,  and  being,  many  of  them,  in  no  wise  discomfited  by 
the  neighbourhood  of  our  own  species.  Several  of  them  are 
capable  of  prolonging  and  interrupting  their  lives  in  the  winged 
condition  to  suit  our  climate  ;  and  this  in  a  manner  that  can 
scarcely  be  called  hibernation,  for  they  frequently  take  up  the 
position  of  repose  when  the  weather  is  still  warm,  and  on  the 
other  hand  recommence  their  activity  in  the  spring  at  a  very 
early  period.  This  phenomenon  may  frequently  be  noticed  iu 
the  Tortoise-shell  butterfly  ;  it  is  as  if  the  creature  knew  1:1  uit 
however  warm  it  may  be  in  the  autumn  there  will  be  no  more 
growth  of  food  for  its  young,  and  that  in  the  spring  vegetation 

1  1'.  i'ii/.  ,W.  LfDulun,  1879,  p.  xxix. 
2  Allen's  Naturalists'  Library,  Butterflies,  i.  1896. 


vr  BUTTERFLIES NYMPHALIDES  353 

is  sure  to  be  forthcoming  and  abundant  before  long,  although 
there  may  be  little  or  none  at  the  time  the  creature  resumes 
its  activity.  It  is  probable  that  the  habit  may  be  in  some 
way  connected  with  an  imperfect  activity  of  the  sexual  organs. 
It  should,  however,  be  recollected  that  many  larvae  of  butterflies 
hibernate  as  young  larvae  after  hatching,  and,  sometimes,  with- 
out taking  any  food.  Pyrameis  cardui,  the  Painted  Lady,  is, 
taking  all  into  consideration,  entitled  to  be  considered  the  most 
ubiquitous  of  the  butterfly  tribe.  Its  distribution  is  very  wide, 
and  is  probably  still  extending.  The  creature  is  found  in 
enormous  numbers  in  some  localities,  especially  in  Northern  and 
Eastern  Africa  ;  and  when  its  numbers  increase  greatly,  migration 
takes  place,  and  the  Insect  spreads  even  to  localities  where  it 
cannot  maintain  itself  permanently.  In  Britain  it  is  probably 
during  some  years  nearly  or  quite  absent,  but  may  suddenly 
appear  in  large  numbers  as  an  immigrant.  The  favourite  food 
of  the  larva  is  thistles,  but  many  other  plants  serve  the  Insect 
at  times. 

I'linessa,  or  Pyrameis,1  atalanta,  the  Red  Admiral,  is  common 
in  the  Palaearctic  and  Nearctic  regions,  and  extends  its  range  to 
various  outlying  spots.  The  most  remarkable  of  these  is  the 
remote  Hawaiian  Islands,  where  the  Insect  appears  really  to  be 
m»w  at  home,  though  it  is  associated  with  a  larger  and  more 
powerful  congener,  P.  tameamea.  Another  interesting  Yauessid  is 
Araschnia  levana,  which  is  peculiar  to  Europe,  where  it  produces 
annually  two  generations  so  dissimilar  to  one  another  that  they 
passed  current  as  two  species,  V.  levana  and  V.  prorsa.  Although 
intermediate  forms  are  rare  in  nature  they  can  be  induced  by 
certain  treatments  applied  to  the  larvae  under  human  control. 

The  dead-leaf  butterflies  of  the  genus  Kallima  belong  to 
Xymphalides.  They  are  so  shaped  and  coloured  that  when 
settled,  with  wings  closed,  on  a  twig,  the  appearance  is  exactly 
that  of  a  dry  leaf:  the  exposed  surface  is  mottled  with  spots 
that  look  just  like  the  patches  of  minute  fungi,  etc,  that  are  so 
common  on  decaying  vegetation.  The  colour  and  the  spots  on 
the  under  surface  of  this  butterfly  are  very  variable.  According 
to  Mr.  Skertchly,'2  we  may  presume  that  in  the  minute  details  of 

1  A  most  unfortunate  diversity  exists  in  the  generic  names  applied  to  these 
1'unessa,  as  well  as  in  those  of  many  other  Lepidoptera. 
-Ann.  Xat.  Hist.  (6),  iv.  1889,  p.  212. 
VOL.    VI  2   A 


354  LEPIDOPTERA  CHAP. 

these  resemblances  we  have  a  case  of  hypertely  similar  to  that 
of  the  resemblance  to  Insects'  minings  exhibited  by  certain  marks 
OH  the  tegmina  of  Pterochroza  (mentioned  in  Vol.  V.  p.  322). 

In  South  America  there  is  a  somewhat  peculiar  genus  of 
Nymphalides — Agcronia — that  delights  in  settling  on  the  trunks 
of  trees  rather  than  on  flowers  or  leaves.  It  was  long  since  noticed 
that  the  species  of  Ayeronia  make  a  clicking  noise  ;  in  some  cases 
when  on  the  wing,  in  other  cases  by  moving  the  wings  when  the 
Insect  is  settled.  The  object  of  the  noise  is  quite  uncertain  ;  it 
has  been  suggested  that  it  is  done  in  rivalry  or  courtship,  or  to 
frighten  away  enemies.  Bigg- Wether  found,  however,  that  in 
South  Brazil  there  is  a  lazy  little  bird  to  which  this  sound  serves 
as  a  signal,  inducing  it  to  descend  from  its  perch  and  eat  the  clicker. 
The  mode  in 'which  the  noise  is  produced  is  not  quite  clear.  Sir 
George  Hampson  has  pointed  out l  that  the  fore  wing  bears  at 
the  extreme  base  a  small  appendage  bearing  two  hooks,  and  that 
two  other  processes  on  the  thorax  play  on  these  when  the  wing 
moves.  His  suggestion  that  these  hooks  are  the  source  of  the 
sound  seems  highly  probable. 

There  is  a  great  variety  in  the  larvae  of  Nymphalides.  In 
the  Vanessa  group  the  body  is  armed  with  spines,  each  one  of 
which  bears  shorter  thorns,  the  head  being  unadorned.  The 
Fritillaries  (Argynnis,  Melitaea]  also  have  caterpillars  of  this  kind. 
In  many  other  forms  the  head  itself  is  armed  with  horns  or  spines 
of  diverse,  and  frequently  remarkable,  character.  In  Apatwa  and 
its  allies  the  body  is  without  armature,  but  the  head  is  perpen- 
dicular, the  vertex  bifid  and  more  or  less  prolonged.  The 
caterpillar  of  our  Purple  Emperor,  Apatura  iris,  is  quite  unlike 
any  other  British  caterpillar ;  in  colour  it  is  like  a  Sphingid 
larva — -green  with  oblique  lateral  stripes  of  yellow  and  red — but 
in  form  it  is  slug-like,  pointed  behind,  and  it  has  on  the  head 
two  rather  long  tentacle-like  horns.  In  the  South  American  genus 
Prepona,  the  larva  of  which  in  general  form  resembles  that  of 
Apatura,  there  are  no  anal  claspers,  but  the  extremity  of  the  body 
is  prolonged,  forming  a  sort  of  tail. 

Fam.    2.   Erycinidae  (Lemoniidae  of  some  authors). --The 

female  has  six  perfectly  formed  leys,  tlmuyli  fj/e  front  pair  is  smaller. 

The  male  has  the  coxae  of  the  front  leys  for  in  ing  a  spine,  and  the 

tarsi  unjointed,  withoitt  claws.     This  family  consists  of  about  1000 

1  P.  Zool.  Sue.  London,  ]S92,  ]>.  191. 


vi  BUTTERFLIES — ERYCINIDAE  355 

species,  usually  of  rather  small  size,  exhibiting  a  great  variety  of 
shape  and  coloration,  some  of  them  being  remarkably  similar  to 
some  of  the  gay,  diurnal  moths  of  South  America.  The  palpi  are 
usually  small,  but  in  Ourocnemis  they  are  large  and  porreet.  The 
family  is  specially  characteristic  of  tropical  America,  but  there  is 
one  small  group  of  30  or  -40  species,  Nemeobiides,  in  the  Eastern 
Hemisphere.  We  have  one  species  in  Britain,  Nemeohius  lucina, 
the  Duke  of  Burgundy  Fritillary.  Neither  the  larvae  nor  the 
pupae  of  Erycinidae  present  any  well-marked  characteristic 
feature,  but  exhibit  considerable  variety.  According  to  Bar,1 
some  of  the  larvae  are  like  those  of  moths  ;  the  caterpillar  of 
Meliboeus  is  said  to  be  like  that  of  a  Liparis :  the  chrysalis  has 
the  short,  rounded  form  of  that  of  the  Lycaenidae,  and  is  sus- 
pended with  the  head  down,  and  without  a  band  round  the 
body.  The  larvae  of  Eurygona  .are  gregarious.  The  pupae  of  some 
other  forms  adhere,  heads  downwards,  to  branches.  Scudder 
considers  that  this  family  is  not  distinct  from  Lycaenidae,  and 
that  the  Central  American  genus  Eumaeus  connects  the  two. 
Eeuter  also  treats  Erycinidae  as  a  division  of  Lycaenidae. 

Sub-Fam.  1.  Erycinides. — [Characters of 'the family .]  Palpi 
not  unusually  large.  We  place  all  the  Erycinidae  in  this  sub- 
family except  the  following— 

Sub-Fam.  2.  Libytheides. — Butter  flics  of  average  size,  with 
the  palpi  large  and  porreet:  the  front  legs  of  the  male  small,  the 
tarsus  reduced  to  one  joint:  the  front  leg  of  the  female  of  the 
normal  structure,  and  hut  little  reduced  in  size.  This  division 
consists  of  the  single  genus  Liliythea,  with  only  a  score  of  species. 
They  are  Insects  somewhat  like  Vanessa,  in  appearance,  but  tan- 
not  fail  to  be  recognised  on  account  of  the  peculiar  palpi.  The 
genus  is  of  very  wide  distribution,  occurring  in  most  parts  of  the 
warm  and  temperate  continental  regions,  and  it  also  occurs  in 
Mauritius  and  the  Antilles. 

The  Libytheides  have  given  rise  to  much  difference  of  opinion 
amongst  systematists,  some  of  whom  assign  them  as  a  sub- 
family to  the  Erycinidae,  some  to  the  Nymphalidae  ;  while  others 
treat  them  as  a  family  apart.  The  families  Nymphalidae,  Ery- 
cinidae and  Lycaenidae  are  so  intimately  allied,  that  Scudder  is 
probably  correct  in  considering  them  to  form  really  one  huge 
family ;  if  this  view  were  adopted  there  would  be  no  difficulty 

1  Bull.  8oc.  cnt.  France,  1856,  pp.  c,  ci. 


LEPIDOPTERA  CHAP. 


iu  locating  Libythea  therein.  If  they  he  kept  apart,  it  is  almost 
necessary  to  separate  Libythca  also;  though  possibly  its  claims 
to  he  placed  in  Erycinidae  slightly  preponderate.  The  recently 
described  germs  Ourocnemis  to  some  extent  connects  Erycinides 
with  Libythaeides.1 

Fam.  3.  Lycaenidae. — The  front  legs  but  little  smaller  than 
the  others  :  in  t/tr  male,  however,  the  tarsus,  though  elongate,  is  only 
of  one  joint,  and  is  terminated  by  a  single  claw.  No  pad  on  the 
front  tibia.  Claws  not  toothed.  The  Lycaenidae,  or  Blues,  are,  as 
a  rule,  of  small  size,  but  in  the  tropics  there  are  many  that  reach 
the  average  size  of  butterflies,  i.e.  something  about  the  stature  of 
the  Tortoise-shell  butterfly.  The  family  is  one  of  the  larger  of 
the  divisions  of  butterflies,  considerably  more  than  2000  species 
being  at  present  known,  and  this  number  is  still  rapidly  increas- 
ing. Although  blue  on  a  part  of  the  upper,  surface  is  a  very 
common  feature  in  the  group,  it  is  by  no  means  universal,  for 
there  are  many  "  Coppers,"  as  well  as  yellow  and  white  Lycae- 
nidae. Many  species  have  delicate,  flimsy  appendages — tails— 
to  the  hind  wings,  but  in  many  others  these  are  quite  absent ; 
and  there  are  even  tailed  and  tailless  forms  of  the  same  species. 
The  members  of  the  group  Lipteninae  (Liptena,  Vanessnla, 
Miinarraea,  etc.)  resemble  members  of  other  sub-families  of  Xym- 
phalidae,  and  even  of  Pieridae.  Lycaenidae  are  well  represented 
wherever  there  are  butterflies ;  in  Britain  we  have  1 8  species. 

The  larvae  of  this  family  are  very  peculiar,  being  short,  thicker 
in  the  middle,  and  destitute  of  the  armature  of  spines  so  remark- 
able in  many  other  caterpillars.  It  has  of  late  years  been  fre- 
quently recorded  that  some  of  these  larvae  are  attended  by  ants, 
which  use  their  antennae  to  stroke  the  caterpillars  and  induce 
them  to  yield  a  fluid  of  which  the  ants  are  fond.  Gueiiee  had 
previously  called  attention  L>  to  the  existence  of  peculiar  structures 
contained  in  small  cavities  on  the  posterior  part  of  the  cater- 
pillar of  Lycacna,  baetica.  These  structures  can  be  evaginated, 
and,  it  is  believed,  secrete  a  fluid ;  Edwards  and  M'Cook  are  of 
opinion  that  they  are  the  source  of  the  matter  coveted  by  the 
ants.  The  larvae  are  without  spines. 

The  caterpillars  of  the  Blues  have  some  of  them  strange  tastes ; 
more  than  one  has  been  recorded  as  habitually  feeding  on  Aphidae 

1  Baker,  Tr.  ent.  Soc.  London,  1887,  p.  175,  PI.  ix. 

2  Ann.  Soc.  ent.  France  (4),  vii.  18(i7,  ]i.  (!(.>,">,  PI.  xiii. 


vi  BUTTERFLIES LYCAENIDAE — PIERIDAE  357 


and  scale-Insects.  The  pupae  are,  like  the  larvae,  of  short 
inflated  form.  By  a  remarkable  coincidence,  the  pupae  of  two 
species  bear  a  considerable  resemblance  to  the  heads  of  monkeys, 
or  mummies.  The  Lycaenid  pupa  is  usually  extremely  consoli- 
dated, destitute  of  movement,  and  is  supported — in  addition  to 
the  attachment  by  the  cremaster — by  a  silk  thread  girdling  the 
middle.  There  are  exceptions  to  these  rules,  and  according  to 
Mr.  liobson  the  pupa  of  Tajuria  diaeus  hangs  free,  suspended 
from  a  leaf,  and  can  move  the  body  at  the  spot  where  the 
abdominal  segments  meet  the  wing-cases  in  the  dorsal  line.1 

Fam.  4.  Pieridae. — The  six  legs  well  developed,  and  similar 
in  the  sexes  ;  there  is  no  pad  on  the  front  tibia.  The  claws  of  all 
the  feet  are  li/id,  or  toothed,  and  there  is  an  empodium.  There 
are  upwards  of  1000  species  of  Pieridae  already  known.  Al- 
though several  taxonomists  treat  the  Pieridae  and  Papilionidae 
as  only  subdivisions  of  one  family,  yet  they  appear  to  be  quite 
distinct,  and  the  relationships  of  the  former  to  be  rather  with 
Lycaenidae.  In  Pieridae,  white,  yellow,  and  red  are  the  pre- 
dominant colours,  though  there  is  much  black  also.  It  lias 
recently  been  ascertained  that  the  yellow  and  red  pigments,  as 
well  as  the  white,  are  uric  acid  or  derivatives  therefrom.2  The 
physiology  of  this  peculiarity  has  not  yet  been  elucidated,  so 
that  we  do  not  know  whether  it  may  be  connected  with  some 
state  of  the  Malpighiaii  vessels  during  metamorphosis. 

Our  Garden-White,  Brimstone,  Clouded-yellows  and  Orange-tip 
butterflies  belong  to  this  family  ;  as  does  also  the  South  American 
genus  formerly  called  Leptalis.  This  generic  name,  which  is 
much  mentioned  in  literature  owing  to  the  resemblance  of  the 
species  of  the  genus  to  Heliconiides,  has  now  disappeared  ;  Leptalis 
having  been  divided  into  various  genera,  while  the  name  itself 
is  now  considered  merely  a  synonym  of  Dismoi^h  ia. 

The  African  Insect,  Pseudopontia  paradoxa,  has  nearly  trans- 
p;  i  rent  wings,  no  club  to  the  antennae,  a  remarkably  small  cell  on 
the  wing,  and  an  arrangement  of  the  nervules  not  found  in  any 
other  butterfly ;  there  being  only  ten  nervules  at  the  periphery  of 
the  front  wing,  and  both  upper  and  lower  radial  nervules  uniting 
with  the  posterior  branch  of  the  subcostal.  It  has  been  treated 
as  a  moth  by  several  entomologists.  Aurivillius  considers  that  it 

1  /.  Bombay  Soc.  ix.  1895,  pp.  338-341. 

-  Hopkins,  Phil.  Trans.  186  B,  1895,  p.  661. 


353 


LEPIDOPTERA 


CHAP. 


is  certainly  a  butterfly ;  but  as  the  metamorphoses  are  unknown, 
we  cannot  yet  form  a  final  opinion  as  to  this  curious  form.  The 
extraordinary  Peruvian  Insect,  Styx  inf emails,  is  also  placed  in 
this  family  by  Staudinger  ;  it  is  a  small,  pale  Insect,  almost  white, 
and  with  imperfect  scales  ;  a  little  recalling  a  Satyrid.  It  appears 
to  be  synthetic  to  Pieridae  and  Erycinidae. 

The  caterpillars  of  Pieridae  are   perhaps  the  least  remarkable 
or  attractive   of  all  butterfly-caterpillars ;   their   skins  are   as  a 

rule  bare,  or  covered  only  with  fine,  short 
down  or  hair ;  their  prevalent  colour  is 
green,  more  "or  less  speckled  with  black 
and  yellow,  and  they  are  destitute  of  any 
prominent  peculiarities  of  external  struc- 
ture. Pupation  is  accomplished  by  the 
larva  fixing  itself  to  some  solid  body  by  the 
posterior  extremity,  with  the  head  upwards 
(or  the  position  may  be  horizontal),  and  then 
placing  a  girdle  round  the  middle  of  the 
body.  The  pupa  never  hangs  down  freely 
as  it  does  in  Xymphalidae.  It  has  been 
by  experiment  that  if  the 


B 


9     ? 


FIG.   ISO.—  Pupation  of  the 

Orange  -  tip      butterfly,   ascertained 

XucMoe  examines.    A,       ifdl  d    t}        j  b  fc     tj 

Ine  completed  pupa  ;  B, 

the  larva,  with  its  girdle,   tion   can   nevertheless   be  accomplished   by 

prepared  for  the  change.     ft  consitlerable  propol.tion    of    larvae.       Some 

of  the   pupae   are   of  very  peculiar  form,  as  is   the   case   in   the 

Orange-tip  (Fig.  180,  A)  and  Brimstone  butterflies.     The  Orange- 

tip  butterfly  passes  nine  or 

ten  months  of  each  year  as 

a    pupa,    which    is  variable 

in  colour  ;   perhaps   to  some 

extent    in   conformity   with 

its  surroundings.    The  North 

American   E.  genutia  has  a 

similar  life-history,  but   the 

larva  leaves  its  Cruciferous 

food-plant,     wanders     to     an    FIG.  181.—  Newly-hatched  larva  of  Euchloe  car- 

A'  ^  If?  jn  Profil<:  ;  *•  01f 

segment  more  magnified,  showing  the  liquid- 
bearing  setae  ;  C,  one  of  the  setae  still  more 
magnified,  and  without  liquid. 


oak  tree,  and  there  turns  to 

a  pupa,  resembling  in  colour 


the  bark  of  the  tree. 

It   is  riot  unusual  for  caterpillars  to  change  their  habits  and 


VI 


BUTTERFLIES  —  PIERIDAE PAPILIONIDAE 


359 


appearance  in  a  definite  manner  in  the  course  of  the  larval  life. 
The  caterpillar  of  Eucliloe  cardamines  exhibits  a  larval  meta- 
morphosis of  a  well-marked  character.  The  young  larva  (Fig. 
181)  is  armed  with  peculiar  setae,  furcate  at  the  tip,  each  of 
which  bears  a  tiny 
ball  of  fluid.  In  this 
stage  the  caterpillar 
makes  scarcely  any 
movement.  In  the 
middle  of  the  cater- 
pillar's life  a  new 
vestiture  appears 
after  an  ecdysis  ; 
numerous  fine  hairs 

are  present,  and  the  FIG.  182. —Larva  of  Euchloe.  cardamines  in  middle  life. 
fluid -bearilio-  spines  A>  thu  larva  iu  frotile  ;  B-  one  segme"t  more  magnified. 

nearly  disappear,  being  reduced  to  a  single  series  of  spines  of  a 
comparatively  small  size  on  each  side  of  the  upper  middle  region 
of  the  body  (Fig.  182).  The  colour  is  also  a  good  deal 
changed,  and  concomitantly  there  is  a  much  greater  voracity 
and  restlessness. 

Fam.  5.  Papilionidae. — All  the  legs  well  developed.  Claws 
large,  simple,  without  empodium.  Front  tibiae  with  a  pad.  The 
metanotum  free,  conspicuously  exposed  between  mesonotum  and 
abdomen.  This  series  of  butterflies  includes  some  of  the  most 
magnificent  of  the  members  of  the  Insect  world.  It  is  considered 
by  some  authorities  to  be  the  highest  family  of  butterflies ;  and 
in  one  very  important  feature — sexual  differentiation — it  cer- 
tainly is  entitled  to  the  rank.  There  are  about  700  recorded 
species,  the  larger  portion  of  which  are  included  in  the  genus 
Papilio.  The  great  variety  of  form  has  led  to  this  genus  being 
divided ;  the  attempts  have,  however,  been  partial,  with  the 
exception  of  an  arrangement  made  by  Felder,  who  adopted  75 
sections,  and  a  recent  consideration  of  the  subject  by  Haase,  who 
arranges  Felder 's  sections  into  three  sub-genera.  Many  of  the 
sections  have  received  names,  and  are  treated  by  some  authors  as 
genera,  so  that  an  unfortunate  diversity  exists  as  to  the  names 
used  for  these  much-admired  Insects.  The  genus  is  distributed 
all  over  the  world,  but  is  perhaps  nowhere  more  numerous  in 
species  than  in  South  America.  Wallace  informs  us  that  the  great 


360 


LEPIDOPTERA 


CHAP.   VI 


majority  of  the  species  of  the  Amazon  valley  frequent  the  shady 
groves  of  the  virgin  forest.  In  many  cases  the  sexes  are  ex- 
tremely different  in  appearance  and  habits,  and  are  but  rarely 
found  together  in  one  spot.  The  genus  Ornitlioptera  is  closely 


allied  to  Papilio,  and  contains  some  of  the  most  remarkable  of 
butterflies,  the  homes  of  the  species  being  the  islands  of  the  Malay 
Archipelago,  and  outlying  groups  of  islands,  there  being  a  smaller 
number  of  species  in  the  neighbouring  continents.  The  females 
are  of  great  size,  and  are  so  excessively  different  from  their 


362  l.KI'IDOPTERA  CHAP. 

consorts  of  the  other  sex,  as  to  arouse  in  the  student  a  feeling  of 
surprise,  and  a  strong  desire  to  fathom  the  mysteries  involved.  It 
would  L)e  difficult  to  surpass  the  effective  coloration  of  the  males 
in  many  of  the  species  of  Ornithoptera  ;  they  are,  too,  very  diverse 
in  this  respect ;  0.  brookiana  is  of  an  intense  black  colour,  with 
a  band  of  angular  green  marks  extending  the  whole  length  of 
its  wings,  while  behind  the  head  there  is  a  broad  collar  of  crimson 
colour.  Perhaps  the  most  remarkable  of  all  is  the  0.  paradisea, 
recently  discovered  in  New  Guinea ;  in  this  species  the  sexual 
disparity  reaches  its  maximum.  The  female  (Fig.  184)  is  a 
large,  sombre  creature  of  black,  white  and  grey  colours,  but  the 
male  (Fig.  183)  is  brilliant  with  gold  and  green,  and  is  made 
additionally  remarkable  by  a  long  tail  of  unusual  form  on  each 
hind  wing. 

We  may  anticipate  that  these  extraordinary  cases  of  sexual 
total  dissimilarity  in  appearance  are  accompanied  by  equally 
remarkable  habits  and  physiological  phenomena.  In  the  case  of 
0.  li-imkitrtift.  the  female  is  extremely  rare,  so  that  the  collector, 
Kiinstler,  could  only  obtain  fifteen  females  to  a  thousand  males. 
According  to  Mr.  Skertchly,  instead  of  the  crowd  of  males  being- 
eager  to  compete  for  the  females,  the  reverse  is  the  case  ;  the 
female  diligently  WTOOS  the  male,  who  exhibits  a  reluctance  to 
coupling.  This  observer  apparently  considered  that  the  "  emerald 
feathers  "  of  the  male  are  a  guide  or  incitement  to  the  female.1 

In  Africa  Ornithoptera  is  to  a  certain  extent  represented 
by  two  extremely  remarkable  forms,  Papilio  zalmoxis  and  P. 
(Druri/a*)  antirnachus.  There  are  about  a  dozen  other  genera  of 
Papilionidae ;  most  of  them  contain  but  few  species.  Parnassius, 
however,  is  rich  in  species  inhabiting  the  mountains  and  elevated 
plateaus  of  the  northern  hemisphere  in  both  the  Old  and  Xew 
Worlds  ;  it  is  remarkable  for  the  small  amount  of  scales  on  the 
wings,  and  for  the  numerous  variations  of  the  species.  The  female 
possesses  a  peculiar  pouch  at  the  end  of  the  body ;  although  only 
formed  during  the  process  of  coupling,  it  has  a  special  and 
characteristic  form  in  most  of  the  species.  The  curious  Indian 
genus  Leptt>rir<-tfH  has  parts  of  the  front  wings  transparent,  while 
the  hind  pair  form  long  tails.  This  genus  is  of  interest  in  that 

1  Ann.  Nat.  ///*/.  (6),  iv.  1889,  p.  213.  "We  trust  there  will  not  bo  many  more 
Kiinstlcrs.  as  this  beautiful  butterfly  must  certainly  become  extinct,  if  the  female 
1)0  really  as  rare  as  is  supposed. 


vi  BUTTERFLIES— SKIPPERS  363 

it  is  said  to  connect  Papilionidae  to  some  extent  with  Hesperiidae. 
The  larvae  of  this  family  are  remarkable  on  account  of  a  curious 
process  on  the  thoracic  segment  called  an  "  osmeterium."  It  is 
usually  retracted,  but  at  the  will  of  the  caterpillar  can  be  everted 
in  the  form  of  a  long  furcate  or  Y-shaped  process ;  there  is  a 
gland  in  the  osmeterium,  and  as  a  result  a  strong  odour  is 
emitted  when  the  exstulpation  occurs. 

The  pupation  of  Papilionidae  is  similar  to  that  of  Pieridae, 
the  pupa  being  placed  with  the  head  upwards,  fixed  by  the  tail, 
and  girt  round  the  middle.  A  very  curious  diversity  of  pupation 
occurs  in  the  genus  Thais,  in  which  the  pupa  is  attached  by  the 
tail  as  usual,  and — which  is  quite  exceptional — also  by  a  thread 
placed  at  the  top  of  the  head.  Scudder  thinks  there  is  also  a 
girdle  round  the  middle,  but  Dr.  Chapman  inclines  to  the  view 
that  the  thread  attaching  the  head  is  really  the  median  girdle 
slipped  upwards.  The  pupation  of  Parnassius  is  exceptional, 
inasmuch  as,  like  Satyrides,  it  is  terrestrial,  in  a  slight  construc- 
tion of  silk. 

Fam.  6.  Hesperiidae  (Skippers). — -Six perfect  legs:  metanotum 
not  free,  largely  covered  Toy  the  mesonotum.  A  pad  on  the  front  tibia. 
Claws  short  and  thick  ;  empodium  present.  Although  this  family 
has  been  comparatively  neglected  by  entomologists,  upwards  of 
2000  species  and  more  than  200  genera  are  known,  and  it  is  not 
improbable  that  it  may  prove  to  be  as  extensive  as  JSTymphalidae. 
We  have  already  said  that  Hesperiidae  is  generally  admitted  to 
be  the  most  distinct  of  the  butterfly  groups.  It  has  been  thought 
by  some  taxonomists  to  be  allied  to  Papilionidae,  but  this  is  a 
mistake.  It  is  undoubtedly  more  nearly  allied  to  Heterocera, 
and  when  the  classification  of  Lepidoptera  is  more  advanced,  so 
that  the  various  natural  groups  placed  in  that  sub-Order  are 
satisfactorily  distinguished,  it  is  probable  that  Hesperiidae  will 
be  altogether  separated  from  Rhopalocera.  We  have  already 
mentioned  that  E.  Reuter  considers  the  Hesperiidae  to  be  phylo- 
genetically  unconnected  with  Rhopalocera  proper;  but  though 
quite  ready  to  admit  that  he  will  probably  prove  correct  in  this, 
wTe  think  Lepidopterists  will  not  be  willing  to  recognise  the 
family  as  a  sub-Order  equivalent  in  value  to  all  Heterocera. 

The  body  is  shorter  and  thicker  than  it  is  in  most  butterflies, 
and  is  pointed  at  the  tip  rather  than  knobbed  or  bent  down- 
wards; the  wings  are  less  ample;  the  antennae  are  not  truly 


364  LEPIDOPTERA  CHAP. 

knobbed,  but  are  thicker  before  the  actual  tip,  which  is  itself 
pointed  and  more  or  less  bent  backwards,  so  that  the  antennae 
are  somewhat  hook-shaped. 

In  habits  as  well  as  structure  the  family  is  markedly  distinct 
from  butterflies;  the  pupation  is  peculiar,  and  the  name  Skipper 
has  been  applied  to  the  perfect  Insects,  because  so  many  of  them 
indulge  in  a  brief,  jerky  flight,  instead  of  the  prolonged  aerial 
courses  characteristic  of  the  higher  butterflies. 

There  is  great  difference  among  the  members  of  the  family, 
and  some  of  them  possess  a  very  high  development  of  the  powers 
of  locomotion,  with  a  correspondingly  perfect  structure  of  the 
thoracic  region,  so  that,  after  inspection  of  these  parts,  we  can 
quite  believe  Wallace's  statement  that  the  larger  and  strong- 
bodied  kinds  are  remarkable  for  the  excessive  rapidity  of  their 
flight,  which,  indeed,  he  was  inclined  to  consider  surpassed  that 
of  any  other  Insects.  "  The  eye  cannot  follow  them  as  they  dart 
past ;  and  the  air,  forcibly  divided,  gives  out  a  deep  sound  louder 
than  that  produced  by  the  humming-bird  itself.  If  power  of 
wing  and  rapidity  of  flight  could  place  them  in  that  rank,  they 
should  be  considered  the  most  highly  organised  of  butterflies." 
It  was  probably  to  the  genera  Pyrrliopyge,  Ery  tides,  etc.,  that 
Mr.  Wallace  alluded  in  the  above  remarks.  Although  the  Hes- 
periidae  are  not  as  a  rule  beautifully  coloured,  yet  many  of  these 
higher  forms  are  most  tastefully  ornamented  ;  parts  of  the  wings, 
wing-fringes,  and  even  the  bodies  being  set  with  bright  but  agree- 
able colours.  We  mention  these  facts  because  it  is  a  fashion  to 
attribute  a  lowly  organisation  to  the  family,  and  to  place  it  as 
ancestral  to  other  butterflies.  Some  of  them  have  crepuscular 
habits,  but  this  is  also  the  case  with  a  variety  of  other  Ehopalo- 
cera  in  the  tropics. 

In  their  early  stages  the  Skippers — so  far  as  at  present  known 
—depart  considerably  from  the  majority  of  butterflies,  inasmuch 
as  they  possess  in  both  the  larval  and  pupal  instars  habits  of  con- 
cealment and  retirement.  The  caterpillars  have  the  body  nearly 
bare,  thicker  in  the  middle,  the  head  free,  and  more  or  less 
notched  above.  They  make  much  greater  use  of  silk  than  other 
butterfly-larvae  do,  and  draw  together  leaves  to  form  caves  for 
concealment,  and  even  make  webs  and  galleries.  Thus  the  habits 
are  almost  those  of  the  Tortricid  moths.  Pupation  takes  place 
under  similar  conditions  ;  and  it  is  interesting  to  find  that  Chap- 


VI 


HESPERIIDAE SKIPPERS 


365 


man  considers  that  the  pupa  in  several  points  of  structure  re- 
sembles that  of  the  small  moths.  Not  only  does  the  larva  draw 
together  leaves  or  stalks  to  make  a  shelter  for  the  pupa,  hut  it 
frequently  also  forms  a  rudimentary  cocoon.  These  arrangements 
are,  however,  very  variable,  and  the  accounts  that  have  been 
given  indicate  that  even  the  same  species  may  exhibit  some 
amount  of  variation  in  its  pupation.  Scudder  considers  that,  in 
-the  North  American  Skippers,  the  cremaster  is  attached  to  a  single 
Y-like  thread.  In  other  cases  there  is  a  silk  pad  on  the  leaf  for 
the  cremaster  to  hook  on.  An  interesting  account  given  by  Mr. 
Dudgeon  of  the  pupation  of  a  common  Indian  Skipper,  Badamia 
exclamationis,  shows  that  this  Insect  exercises  considerable  in- 


FIG.  185. —Pupation  of 
Badam  ia  exclamation  is. 
(After  Dudgeon.  J. 
.Bombay  Soc.  x.  1895, 
p.  144).  A,  One  side 
of  the  leaf-cradle,  the 
other  (nearest  to  the 
observer)  being  broken 
away  ;  B,  transverse  sec- 
tion of  entire  cradle.  </, 
The  pupa  ;  b,  fastenings 
of  perpendicular  threads 
round  pupa  ;  c,  cross 
thread  retaining  the  leaf 
m  cradle  form  ;  d,  mar- 
gins of  the  leaf  ;  e,  mid- 
rib of  leaf. 


genuity  in  the  structure  of  the  puparium,  and  also  that  the 
arrangements  it  adopts  facilitate  one  of  the  acts  of  pupation  most 
difficult  for  such  pupae  as  suspend  themselves,  viz.  the  hooking  the 
cremasters  on  to  the  pad  above  them.  Badamia  uses  a  rolled-up 
leaf  (Fig.  185);  the  edges  of  the  leaf  are  fastened  together  by 
silk  at  d ;  from  this  spot  there  descends  a  thread  which,  when 
it  reaches  the  pupa,  a,  forks  so  as  to  form  an  inverted  Y,  and  is 
fastened  to  the  leaf  on  either  side  ;  the  two  sides  of  the  leaf  are  kept 
together  by  a  cross  thread,  cc.  Mr.  Dudgeon  was  fortunate  enough 
to  observe  the  act  of  pupation,  and  saw  that  "  although  the  anal 
prolegs  of  the  larva  were  attached  to  a  tuft  or  pad  of  silk  in  the 
usual  way,  and  remained  so  until  nearly  the  whole  skin  had  been 
shuffled  off,  yet  when  the  last  segment  had  to  be  taken  out,  the 
pupa  drew  it  entirely  away  from  the  skin  and  lifted  it  over  the 


366  LEPIDOPTERA  CHAP. 


riiipty  skin,  and  by  a  series  of  contortions  similar  to  those  made 
by  an  Insect  in  depositing  an  egg,  it  soon  re-attached  its  anal 
segment  or  cremaster  to  the  wel),  throwing  away  the  cast-off  skin 
by  wriggling  its  body  about." 

Series  II.  Heterocera.     Moths. 

Although  Rhopalocera — if  exclusion  be  made  of  the  Hes- 
periidae — is  probably  a  natural  group,  yet  this  is  not  the  case 
with  Heterocera.  The  only  definition  that  can  be  given  of 
Heterocera  is  the  practical  one  that  all  Lepidoptera  that  are  not 
butterflies  are  Heterocera,.  Numerous  divisions  of  the  Heterocera 
have  been  long  current,  but  their  limits  have  become  more  and 
more  uncertain,  so  that  at  the  present  time  no  divisions  of  greater 
value  than  the  family  command  a  recognition  at  all  general.  This 
is  not  really  a  matter  of  reproach,  for  it  arises  from  the  desire  to 
recognise  only  groups  that  are  capable  of  satisfactory  definition. 

Several  attempts  have  recently  been  made  to  form  a  rough 
forecast  of  the  future  classification  of  moths.  Professor  Comstock, 
struck  by  some  peculiarities  presented  by  the  Hepialidae,  Mierop- 
terygidae  (and  Eriocephalidae),  recently  proposed  to  separate  them 
from  all  other  Lepidoptera  as  a  sub-order  Jugatae.  Comstock's 
discrimination  in  making  this  separation  met  with  general  ap- 
proval. The  character  on  which  the  group  Jugatae  is  based  is, 
however,  comparatively  trivial,  and  its  possession  is  not  suffi- 
cient, as  pointed  out  by  Packard,1  to  justify  the  close  association 
of  Hepialidae  and  Micropterygidae,  which,  in  certain  important 
respects,  are  the  most  dissimilar  of  moths.  The  characters 
possessed  by  the  two  families  in  common  may  be  summarised  by 
saying  that  the  wings  and  wing-bearing  segments  remain  in  a 
low  stage  of  development.  In  nearly  all  other  characters  the 
two  families  are  widely  different.  Packard  has  therefore,  while 
accepting  Comstock's  separation  of  the  families  in  question, 
proposed  a  different  combination.  He  considers  that  Eriocepha- 
lidae should  l)e  separated  from  all  others  as  "  Protolepidoptera  " 
or  "  Lepidoptera  Laciniata,"  while  the  whole  of  the  other  Lepi- 
doptera, comprised  under  the  term  "Lepidoptera  Haustellata," 
are  divided  into  Palaeolepidoptera  (consisting  only  of  Microp- 
terygidae) and  jSTeolepidoptera,  comprising  all  Lepidoptera  (in- 

1  Mem.  Ac.   Jl/'(is.'iingtun,  vii.  1895,  p.  57. 


vi  IIETEROCERA MOTHS  367 

elusive  of  Hepialidae)  except  the  Eriocephalidae  and  Microptery- 
gidae.  The  question  is  rendered  more  difficult  by  the  very  close 
relations  that  exist  between  Micropterygidae  and  a  sub-Order, 
Trichoptera,  of  jSTeuroptera.  Dr.  Chapman,  by  a  sketch  of  the 
classification  of  pupae,1  and  Dyar,  by  one  on  larval  stages,2  have 
made  contributions  to  the  subject ;  but  the  knowledge  of  early 
stages  and  metamorphosis  is  so  very  imperfect  that  the  last  two 
memoirs  can  be  considered  only  as  preliminary  sketches  ;  as  indeed 
seem  to  have  been  the  wishes  of  the  authors  themselves. 

Simultaneously  with  the  works  above  alluded  to,  Mr.  Mey- 
rick  has  given 3  a  new  classification  of  the  Order.  We  allude, 
in  other  pages,  to  various  points  in  Mr.  Meyrick's  classifica- 
tion, which  is  made  to  appear  more  revolutionary  than  it  really 
is,  in  consequence  of  the  radical  changes  in  nomenclature  com- 
bined with  it. 

As  regards  the  various  aggregates  of  families  that  are  widely 
known  in  literature  by  the  names  Bombyces,  Sphinges,  JSToctuae, 
Geometres,  Pyrales,  we  need  only  remark  that  they  are  still 
regarded  as  to  some  extent  natural.  Their  various  limits  being 
the  subject  of  discussion  and  at  present  undecided,  the  groups 
are  made  to  appear  more  uncertain  than  is  really  the  case.  The 
group  that  has  to  suffer  the  greatest  changes  is  the  old  Bom- 
byces. This  series  comprises  the  great  majority  of  those  moths 
that  have  diurnal  habits.  In  it  there  were  also  included  several 
groups  of  moths  the  larvae  of  which  feed  in  trunks  of  trees  or 
in  the  stems  of  plants,  such  as  Cossidae,  that  will  doubtless  prove 
to  have  but  little  connection  with  the  forms  with  which  they  were 
formerly  associated.  These  groups  with  aberrant  habits  are  those 
that  give  rise  to  the  greatest  difficulties  of  the  taxonomist. 

The  following  key  to  the  families  of  Heterocera  is  taken  from 
Sir  G.  F.  Hainpson's  recent  work,  Fauna  of  British  India — J/oM.s.4 
It  includes  nearly  all  the  families  at  present  recognised  among 
the  larger  Lepidoptera  ;  certain  families  5  not  mentioned  in  this 
key  are  alluded  to  in  our  subsequent  remarks  on  the  families  :— 

1  Tr.  cnt.  Soc.  London,  189-3,  p.  97,  with  Suppl.  up.  dt.  1896,  pp.  129  and  567. 

2  Amcr.  Natural,   xxix.   1S95,  p.  1060.     See  also  Ann.  X.   York  Ac.  viii.  1895, 
p.  194,  and  Ent.  Record,  1897,  pp.  136  and  196. 

3  Handbook  of  British  Lepidoptera,  1895. 

4  London,  1892.     Published  under  the  authority  of  the  Secretary  of  State  for 
India  in  Council. 

'  Those  numbered  2,  8,  10,  17,  22.  27.  44,  and  46  in  our  arrangement. 


368  LEPIDOPTERA  CHAP. 


KEY  TO  THE  FAMILIES  OP  MOTHS  l 

N.B. — This  table  is  not  simply  dichotomic  ;  three  contrasted  categories  are  used 
in  the  case  of  the  primary  divisions,  A,  B,  C,  and  the  secondary  divisions, 

I,  II,  III. 

A.  Fore  wing  with  nervule  5  coming  from  the  middle  of  the  discocellulars, 

or  nearer  6  than  4  (Categories  I,  II,  III  =  1-18). 
I.   Frenulum  rudimentary   .          .      Fam.  38.   Epicopeiidae,  see  p.  418 

II.  Frenulum  absent  (Categories  1-8). 

1.   Proboscis  present,  legs  with  spurs  (Cat.  2-5). 

2.   Hind  wing  with  nervule  8  remote  from  7  (Cat.  3  and  4). 

3.  Fore  wing  with  nervule  6  and  7  stalked 

Fam.  39.  Uraniidae,  see  p.  419. 

4.  Fore  wing  with  nervules  6  and  7  not  stalked 

Fam.  5.  Ceratocampidae,  see  p.  375. 

5.   Hind  wing  with  nervule  8  nearly  touching  7  beyond  end  of  cell 

Fam.  4.  Brahmaeidae,  see  p.  374. 
6.   Proboscis  absent,  legs  without  spurs  (Cat.  7  and  8). 

7.  Hind  wing  with  one  internal  nervure 

Fam.  3.  Saturniidae,  see  p.  372. 

8.  Hind  wing  with  two  or  three  internal  nervures 

Fam.  6.   Bombycidae,  see  p.  375. 
III.  Frenulum  present  (Cat.  9-18). 

9.  Antennae  fusiform  [spindle-shaped]  Fam.  9.  Sphingidae,  seep.  380. 
10.  Antennae  not  fusiform  (Cat.  11-18). 

11.  Proboscis  absent  .          .      Fam.  7.  Eupterotidae,  see  p.  376. 

12.  Proboscis  present  (Cat.  13-18). 

13.  Hind  wing  witli  nervule  8  curved  and    almost  touch- 
ing 7  after  end  of  cell ;  nervure  la  reaching  anal  angle 

Fam.  12.  Cymatophoridae,  see  p.  386. 

14.  Hind  wing  with  nervule  8   remote  from   7   after  end  of 

cell  (Cat,  15-18). 

1 5.  Tarsi  as  short  as  tibia,  hairy ;  stoutly  built  moths 

Fam.  11.  Notodontidae,'2  see  p.  383. 

16.  Tarsi  long  and  naked  ;  slightly  built  moths  (Cat. 

17  and  18) 

17.  Fore  wing  with   nervule  7   remote  from  8,  and 
generally  stalked  with  6 

Fam.  40.  Epiplemidae,  see  p.  420. 

18.  Fore  wing  with  nervule  7  given  olf  from  8  ;  hind 
wing  with  nervure  la  short  or  absent 

Fam.  36.  Geometridae,  see  p.  411. 

1  For  explanatory  diagram  of  the  wings,  see  Fig.  161,  I.     When  the  nervuration 
is  obscured  by  the  wing-scales,  it  may  be  rendered  temporarily  visible  by  the  appli- 
cation,  with  a  camel's-hair  brush,  of  a  little  benzine.      The  wings  may  be   per- 
manently denuded  of  their  scales  by  being  placed  for  a  short  time  in  Eau  de  Javelle 
(hypochlorite  of  potash). 

2  The  genus  Cyphanta  (one  species  from  India)  has  nervule  5  of  the  fore  wing 
proceeding  from  the  lower  angle  of  the  cell. 


vi  HETEROCERA MOTHS  369 

B.   Fore  wing  with   nervule  5   coming  from   lower  angle  of  cell  or  nearer  4 

than  6  [see  figures  161  and  162,  pp.  318,  319]  (Categories  19-58). 
19.   Hind  wing  with  more  than  8  nervules  (Cat.  20,  21). 

20.  Proboscis  absent,  no  mandibles  nor  ligula  ;  size  not  very  small 

Fam.  23.  Hepialidae,  see  p.  396. 

21.  Mandibles,  long  palpi  and  ligula  present ;  size  very  small 

Fam.  47.  Micropterygidae,  sec  p.  435. 
22.   Hind  wing  with  not  more  than  8  nervules  (Cat.  23-58). 

23.   Hind    wing    with    nervule    8    remote    from    7    after    origin   of 

nervules  6  and  7  (Cat.  24-51). 
24.   Frenulum  absent  (Cat.  25-29). 

25.  Hind  wing  with  one  internal  nervure  ;  nervule  8  with 
a  precostal  spur,    Fain.  31.  Pterothysanidae,  sec  p.  406. 

26.  Hind  wing  with  two  internal  nervures  (Cat.  27  and  28). 

27.  Hind  wing  with  a  bar  between  nervules  7   and  8 
near  the  base ;  nervure  la  directed  to  middle  of  inner 
margin        .        Fam.  30.  Endromidae,  see  p.  406. 

28.  Hind  wing  with  no  bar  between  nervules  7  and  8  ; 
nervure  la  directed  to  anal  angle 

Fam.  29.  Lasiocampidae,  see  p.  405. 
29.   Hind  wing  with  three  internal  nervures 

Fam.  21.   Arbelidae,  see  p.  396. 
30.   Frenulum  present  (Cat,  31-51). 

31.  Hind  wing  with  nervule  8  aborted, 

Fam.  15.  Syntomidae,  see  p.  388. 

32.  Hind  wing  with  nervule  8  present  (Cat.  33-51). 

33.  Antennae  knobbed     Fam.  1.  Castniidae,  see  p.  371. 

34.  Antennae  filiform,  or  (rarely)  dilated  a  little  towards 

the  tip  (Cat.  35-51). 

35.   Fore  wing  with  nervure  Ic  present  (Cat.  36-43). 
36.   Hind  wing  with  nervule   8   free  from   the 
base  or  connected  with  7  by  a  bar  (Cat. 
37-42). 

37.  Proboscis  present 

Fam.  16.  Zygaenidae,  see  p.  390. 

38.  Proboscis  absent  i^Cat.  39-42). 

39.  Palpi  rarely   absent ;     J    Dinged  ; 
larvae  wood-borers 

Fam.  20.  Cossidae,  see  p.  395. 

40.  Palpi  absent  ;  9  apterous  (Cat.  41, 

'  42). 

41.9   rarely   with    legs;    ^    au(l 
larvae  case-dwellers 
Fam.  19.  Psychidae,  see  p.  392. 
42.   9  and  larvae  free  ' 
Fam.  18.Heterogynidae,seep.392. 

1  This  is  a  mistake  of  Sir  George  Hampson's.  It  has  long  been  known  that  the 
female  of  Hcteroyi/nis  does  not  leave  the  cocoon  (for  references  see  p.  392)  ;  the 
larvae,  however,  do  not  live  in  cases,  as  those  of  Psychidae  do. 

VOL.  VI  -    P 


3/0  LEPIDOPTERA  CHAP. 

43.   Hind  wing  with,  nervule  8  anastomosing 
shortly  with  7 

Fam.  26.  Limacodidae,  see.  p.  401. 
44.   Fore  wing  with  nervure  Ic  absent  (Cat,  45-51). 

45.  Hind  wing  with  nervule  8  rising  out  of  7 

Fam.  34.  Arctiidae,  see  p.  408. 

46.  Hind  wing  with  nervule  8  connected  with  7 

by  a  bar,  or  touching  it  near  middle  of 
cell  (Cat.  47,  48). 

47.  Palpi  with  the  third  joint  naked  and 
reaching  far  above   vertex   of   head ; 
proboscis  present 

Fam.  33.  Hypsidae,  see  p.  408. 

48.  Palpi  not  reaching    above   vertex  of 
head  ;  proboscis  absent  or  very  minute 

Fam.  32.  Lymantriidae,  see  p.  406. 
49.  Hind  wing  with  nervule  8  anastomosing 
shortly  with  7  near  the  base ;  proboscis 
well  developed  (Cat.  50,  51). 

50.  Antennae  more  or  less  thick  towards  tip 

Fam.  35.  Agaristidae,  see  p.  410. 

51.  Antennae  filiform 

Fam.  37.  Noctuidae,  see  p.  414. 

52.   Hind   wing   with   nervule    8   curved    and    nearly   or   quite 
touching  nervule  7,  or  anastomosing  with  it  after  origin  of 
nervules  6  and  7  (Cat,  53-58). 
53.   Hind  wing  with  nervure  Ic  absent  (Cat.  54-57). 

54.   Hind  wing  with  nervule  8  with  a  precostal  spur 

Fam.  24.  Callidulidae,  see  ]).  400. 

")").   Hind  wing  with  nervule   8   with  no  precostal  spur 
(Cat.  56,  57). 

56.  Hind  wing  with,  nervure  la  absent  or  very  short 

Fam.  25.  Drepanidae,  see  p.  400. 

57.  Hind   wing   with   nervure  la  almost   or   quite 
reaching  anal  angle 

Fam.  28.  Thyrididae,  see  p.  404. 
58.   Hind  wing  with  nervure  Ic  present 

Fam.  41.  Pyralidae,  see  p.  420. 

C.   Fore  wing  with   4   nervules    arising  from    the  cell  at  almost   even   dis- 
tances apart  (Cat.  59-66). 
59.  Wings  not  divided  into  plumes  (Cat.  60-63). 

60.   Hind  wing  with  nervule  8  coincident  with  7 

Fam.  13.  Sesiidae,  see  p.  386. 
61.   Hind  wing  with  nervule  8  free  (Cat.  62,  63). 

62.  Fore  wing  with  nervure  Ib  simple  or  with  a  very 
minute  fork  at  base 

Fam.  14.  Tinaegeriidae,  see  p.  387. 

63.  Fore  wing  with  nervure    la   forming  a  large  lurk 

with  Ib  at  base       Fam.  45.  Tineidae,  see  p.  428. 


VI 


HETEROCERA CASTNIIDAE 


371 


04.   Wings  divided  into  plumes  (Cat,  65,  66). 

65.  Fore  wing  divided  into  at  most  two,  hind  wing  into  three 
plumes  .         .         .       Fam.  42.  Pterophoridae,  see  p.  426. 

66.  Fore  wing  and  hind  wing  each  divided  into  three  plumes 

Fam.  43.  Alucitidae  ( =  Orneodidae ;,  see  p.  426. 

Fam.  1.  Castniidae. — The  Insects  of  this  family  combine  to  a 
extent  the  characters  of  Imtterjiies  and  moths.  The  antennae 
are  knvlilm/  or  hooked  at  t/ie  tip,  there  is  a  large  precostal  area  to 
tlte  hind  u-intj.  The  nervules  of  the  front  icing  are  complex  ami 
•<t  itastomose  so  as  to  form  one  or  more  accessory  cells  (Fig.  1 6  2).  This 
important,  but  not  extensive,  family  consists  chiefly  of  forms  found 
in  tropical  America  and  Australia.  The  diversity  of  size,  form  and 
appearance  is  very  great,  and  it  is  probable  that  the  members  of  the 
family  will  be  separated ;  indeed,  taxoiiomists  are  by  no  means 
in  agreement  as  to  the  limits  of  the  family.  The  Castniidae 
are  diurnal  Insects,  and  the  Xorth  American  genus  Megathymus 

is  by  many  con- 
sidered to  belong 
to  the  Ehopalo- 
cera.  Euschemon 
rafflesiae  (Fig.  186) 
is  extremely  like  a 
large  Skipper  with 
long  antennae,  but 
has  a  well-marked 
frenulum.  The 
members  of  the 
Australian  genus 
Sync  mo  it  are  much  smaller,  but  they  also  look  like  Skippers. 
Their  habits  are  very  like  those  of  the  Hesperiidae  ;  they 
Hit  about  in  the  hot  sunshine,  and  when  settling  after  their 
brief  flights,  the  fore  wings  are  spread  out  at  right  angles  to 
the  body,  so  as  to  display  the  more  gaily  coloured  hind 
wings :  at  night,  or  in  cloudy  weather,  the  Insect  rests  on 
blades  of  grass  with  the  wings  erect,  meeting  vertically  over 
the  back,  like  a  butterfly.  Hecatesia,  another  Australian  genus, 
is  now  usually  assigned  to  Agaristidae  ;  its  members  look  like 
moths.  The  male  of  H.  fenestrata  is  provided  with  a  sound- 
producing  organ  similar  to  that  of  the  Agaristid  genus  Aegocera. 
The  Cx tin i«  of  South  America  are  manv  of  them  like 


FIG.  186. — Euschemon  rafflesiae.     Australia.      (After 
Doubleday. ) 


3/2  LEPIDOPTERA  CHAP. 

Nymphalid  butterflies,  but  exhibit  great  diversity,  and  resemble 
butterflies  of  several  different  divisions  of  the  family.1 

The  species  are  apparently  great  lovers  of  heat  and  can 
tolerate  a  very  dry  atmosphere.2  The  transformations  of  very 
few  have  been  observed;  so  far  as  is  known  the  larvae  feed  in 
stems  ;  and  somewhat  resemble  those  of  Goat-moths  or  Leopard- 
moths  (Cossidae) ;  the  caterpillar  of  C.  tliempon  lives  in  the  stems 
of  Brazilian  orchids,  and  as  a  consequence  has  been  brought  to 
Europe,  and  the  moth  there  disclosed.  The  pupae  are  in  general 
structure  of  the  incomplete  character,  and  have  transverse  rows 
of  spines,  as  is  the  case  with  other  moths  of  different  families, 
but  having  larvae  with  similar  habits.3  Casttiia  eudesmia  forms 
a  large  cocoon  of  fragments  of  vegetable  matter,  knitted  together 
with  silk.  These  Insects  are  rare  in  collections  ;  they  do  not  ever 
appear  in  numbers,  and  are  generally  very  difficult  to  capture. 

Fam.  2.  Neocastniidae.  -  -The  Oriental  genus  Tusdna 
formerly  placed  in  Castniidae  has  recently  been  separated  by 
Sir  G.  Hampson  and  associated  with  Neocastnia  nice  rill  el,  from 
East  India,  to  form  this  family.  These  Insects  have  the  appear- 
ance of  Xymphalid  butterflies.  They  differ  from  Castniidae  by 
the  want  of  a  proboscis. 

Fam.  3.  Saturniidae. — This  is  a  large  and  varied  assemblage 
of  moths ;  the  larvae  construct  cocoons ;  the  products  of  several 
species  being  used  as  silk.  These  moths  have  no  frenulum  and 
no  proboscis.  The  hind  wings  have  a  very  large  shoulder,  so 
that  the  anterior  margin  or  costa  stretches  far  forward  beneath 
the  front  wing,  as  it  does  in  butterflies.  The  antennae  of  the 
males  are  strongly  bipectinated  and  frequently  attain  a  magnifi- 
cent development.  The  family  includes  some  of  the  largest 
and  most  remarkable  forms  of  the  Insect-world.  Coscinocera 
lie /rules,  inhabiting  North  Australia,  is  a  huge  moth  which, 
with  its  expanded  wings  and  the  long  tails  thereof,  covers  a 
space  of  about  70  square  inches.  One  of  the  striking  features 
of  the  familv  is  the  occurrence  in  numerous  forms  of  remarkable 

V 

transparent  spaces  on  the  wings ;  these  window  -  like  areas 
usually  occur  in  the  middle  of  the  wing  and  form  a  most  remark- 
able contrast  to  the  rest  of  the  surface,  which  is  very  densely 

1  See  Westwood,  Tr.  Linn.  Soc.  London  (2),  i.  1877,  p.  165,  etc. 
-  For  lial 'its  ol'  some  Brazilian  Gastuia  see  Seitz,  Knt.  Z<-it.  Stettin,  li.  1890,  p.  258. 
3  For  pupa  see  Chapman.  Ent.  Hcc.  vi.  1895,  pp.  286,  288. 


VI 


HETEROCERA SATURNIIDAE 


373 


scaled.  In  Attacas  these  attain  a  large  size.  In  other  species, 
such  as  the  South  African  Ludia  delegorguei,  there  is  a  small 
letter-like,  or  symboliform,  transparent  mark  towards  the  tip  of 
each  front  wing.  We  have  at  present  no  clue  to  the  nature 
or  importance  of  these  remarkable  markings.  In  the  genus 
Automeris,  and  in  other  forms,  instead  of  transparent  spaces 
there  are  large  and  staring  ocellate  marks  or  eves,  which  are 
concealed  when  the  Insect  is  reposing.  In  Arceina,  Copiopteryx, 
E/tdaemonia  and  others,  the  hind  wings  are  prolonged  into  very 
long  tails,  perhaps  exceeding  in  length  those  of  any  other  moths. 


FIG.  187. — Larva  of  Attacus  atlas.     India.     A,  at  end  of  1st  instar,  profile  ;  B,  4th 
instar,  dorsal  view  ;  C,  full-grown  larva,  in  repose.     (After  Poujade.) 

The  cocoons  are  exceedingly  various,  ranging  from  a  slight 
o]  icn  network  to  a  dense  elaborate  structure  arranged  as  in  our 
Emperor  moth  ;  in  this  latter  case  an  opening  is  left  by  the 
larva  for  its  exit  after  it  has  become  a  moth,  but  by  an  ingenious, 
chevaux-de-frise  work,  this  opening  is  closed  against  external 
enemies,  though  the  structure  offers  no  resistance  at  all  to  the 
escape  of  the  moth.  Fabre  has  recorded  some  observations  and 
experiments  which  seem  to  show  that  the  instinct  predominating 
over  the  formation  of  the  cocoon  is  not  cognoscent.  The  Insect, 
if  interfered  with,  displays  a  profound  stupidity.  Its  method  is 
blind  perseverance  in  the  customary.1  The  cocoon  of  Saturniidae 
is  more  often  continuous,  i.e.  entirely  closed.  Packard  says  that 
1  Souvenirs  entomologiques,  quatrieme  serie,  1891,  pp.  39-46. 


374  LEPIDOPTERA  CHAP. 


Actias  In  an  effects  its  escape  by  cutting  through  the  strong 
cocoon  with  an  instrument  situate  at  the  base  of  the  front  wing. 
Other  species  were  examined  and  were  found  to  possess  the  in- 
strument ;  but  Packard  is  convinced  that  the  majority  of  the 
species  possessing  the  instrument  do  not  use  it,  but  escape  by 
emitting  a  fluid  that  softens  the  cocoon  and  enables  the  moth 
to  push  itself  through.1  The  cocoons  of  the  species  of  Ceranclna. 
have  a  beautiful  appearance,  like  masses  of  filagree-work  in  silver. 
The  pupa  in  Ceranchia  is  very  peculiar,  being  terminated  by  a 
long,  spine-like  process.  In  Locpa  newara  the  cocoon  is  of  a 
green  colour  and  suspended  by  a  stalk  ;  looking  like  the  pod,  or 
pitcher,  of  a  plant.  The  silk  of  the  Satu.rni.idae  is  usually  coarse, 
and  is  known  as  Tusser  or  Tussore  2  silk. 

The  larvae  of  this  family  are  as  remarkable  as  the  imagos,  being 
furnished  with  spine-bearing  tubercles  or  warts,  or  long  fleshy 
processes  ;  the  colours  are  frequently  beautiful.  The  caterpillar  of 
Attacus  atlas  (Fig.  187)  is  pale  olive-green  and  lavender,  and  has  a 
peculiar,  conspicuous,  red  mark  on  each  flank  close  to  the  clasper. 

About  seventy  genera  and  several  hundred  species  are  already 
known  of  this  interesting  family.  They  are  widely  distributed 
on  the  globe,  though  there  are  but  few  in  Australia.  Our 
only  British  species,  the  Emperor  moth,  Saturn  i  a  pavonia,  is 
by  no  means  rare,  and  its  larva  is  a  beautiful  object  ;  bright 
green  with  conspicuous  tubercles  of  a  rosy,  or  yellow,  colour.  It 
affects  an  unusual  variety  of  food-plants,  sloe  and  heather  being- 
favourites  ;  the  writer  has  found  it  at  "\Vicken  flourishing  on  the 
leaves  of  the  yellow  water-lily.  Although  the  Emperor  moth  is 
one  of  the  largest  of  our  native  Lepidopterous  Insects,  it  is  one 
of  the  smallest  of  the  Saturniidae. 

The  family  Hemileucidae  of  Packard  is  included  at  present  in 
Saturniidae. 

Fam.  4.  Brahmaeidae.  —  The  species  forming  the  genus 
lii-uli  iiiiica,  have  been  placed  in  various  families,  and  are 
now  treated  by  Hampson  as  a  family  apart,  distinguished 
from  Saturniidae  by  the  presence  of  a  proboscis.  They  are 
magnificent,  large  moths,  of  sombre  colours,  but  with  complex 
patterns  on  the  wings,  looking  as  if  intended  as  designs  for 


r.  Xntural.  xii.  1878,  p.  379. 
2  Cotes,    "Wild   Silk   Insects  of  India,"  I  ml.   Mus.    Xotcs,   ii.    No.    2,    1891, 
15  plates. 


vi  HETEROCERA BRAHMAEIDAE^-BOMBYCIDAE  375 

upholstery.  About  fifteen  species  are  recognised ;  the  geo- 
graphical distribution  is  remarkable  ;  consisting  of  a  comparatively 
narrow  belt  extending  across  the  Old  World  from  Japan  to  West 
Africa,  including  Asia  Minor  and  the  shores  of  the  Caspian  Sea. 
Little  has  been  recorded  as  to  the  life-histories  of  these  Insects. 
The  larva  is  said  to  have  the  second  and  third  segments  swollen 
and  armed  with  a  pair  of  lateral  spines  projecting  forwards.  A 
cocoon  is  not  formed. 

Fam.  5.  Ceratocampidae. — This  is  a  small  family.  They  are 
fine  moths  peculiar  to  the  New  World,  and  known  principally  by 
scattered  notices  in  the  works  of  North  American  entomologists. 
Seven  genera  and  about  sixty  species  are  known.  The  chief 
genus  is  Citlieronia.  Some  of  the  larvae  are  remarkable,  being 
armed  with  large  and  complex  spines.  A  cocoon  is  not  formed. 

Fam.  6.  Bombycidae.  -  In  entomological  literature  this 
name  has  a  very  uncertain  meaning,  as  it  has  been  applied  to 
diverse  groups ;  even  at  present  the  name  is  frequently  used  for 
the  Lasiocampidae.  We  apply  it  to  the  inconsiderable  family 
of  true  silkworm  moths.  They  are  comparatively  small  and 
uninteresting  Insects  in  both  the  larval  and  imaginal  instars  : 
1  tut  the  cocoons  formed  by  the  well-known  silkworm  are  of  great 
value,  and  some  other  species  form  similar  structures  that  are  of 
more  or  less  value  for  commercial  purposes.  The  silkworm  has 
been  domesticated  for  an  enormous  period,  and  is  consequently 
now  very  widely  spread  over  the  earth's  surface ;  opinions  differ 
as  to  its  real  home,  some  thinking  it  came  originally  from 
Northern  China,  while  others  believe  Bengal  to  have  been  its 
native  habitat.  The  silkworm  is  properly  called  Bombyx  mori, 
but  perhaps  it  is  as  often  styled  Sericaria  mori.  Besides  being 
of  so  great  a  value  in  commerce,  this  Insect  has  become  an 
important  object  of  investigation  as  to  anatomy,  physiology  and 
development.  Its  domestication  has  probably  been  accompanied 
by  a  certain  amount  of  change  in  habits  and  instincts,  the 
creature  having  apparently  lost  its  appreciation  of  freedom  and 
its  power  of  flight ;  it  is  also  said  to  lie  helpless  in  certain 
respects  when  placed  on  trees  in  the  larval  state  ;  but  the  import- 
ance of  these  points  has  been  perhaps  somewhat  exaggerated.1 

Although  the  family  Bombycidae  is  very  widely  distributed 
in  the  warmer  regions  of  the  world,  it  includes  only  15  or  20 

1  See  on  this  subject  Perez,  Act.  'Soc.  Bordeaux,  xlvii.  1894,  p.  236,  etc. 


3/6  LEPIDOPTERA 


CHAP. 


genera,  and  none  of  them  have  many  species.  The  Mustiliidae 
of  some  entomologists  are  included  here.  Like  the  Saturniidae, 
the  Bombycidae  are  destitute  of  proboscis  and  of  frenulum  to  the 
wings,  but  they  possess  two  or  three  internal  nervures  on  the 
hind  wing  instead  of  the  single  one  existing  in  Saturniidae. 

Fam.  1.  Eupterotidae  (Striphnopterygidae  of  Aurivillius).- 
This  family  has  only  recently  been  separated  from  Lasiocampidae  ; 
its  members,  however,  possess  a  frenulum  ;  while  none  is  present 
in  the  larger  family  mentioned.  Its  limits  are  still  uncertain, 
but  it  includes  several  extremely  interesting  forms.  The  larvae 
of  the  European  processionary  moth,  Cn<'f/ii><'<///ipa2}rocessionea,&Te 
social  in  habits  ;  they  sometimes  occur  in  very  large  numbers,  and 
march  in  columns  of  peculiar  form,  each  band  being  headed  by  a 
leader  in  front,  and  the  column  gradually  becoming  broader.  It 
is  thought  that  the  leader  spins  a  thread  as  he  goes  on,  and  that 
the  lateral  leaders  of  the  succeeding  files  fasten  the  threads  they 
spin  to  that  of  the  first  individual,  and  in  this  way  all  are 
brought  into  unison.  The  hairs  of  these  caterpillars  are  abun- 
dant, and  produce  great  irritation  to  the  skin  and  mucous  mem- 
brane of  any  one  unlucky  enough  to  come  into  too  close  contact 
with  the  creatures.  This  property  is,  however,  not  confined  to  the 
hairs  of  the  processionary  moths,  but  is  shared  to  a  greater  or 
less  extent  by  the  hairs  of  various  other  caterpillars  of  this 
division  of  Lepidoptera.  In  some  cases  the  irritation  is  believed 
to  be  due  to  the  form  of  the  hair  or  spine,  which  may  be  barbed 
or  otherwise  peculiar  in  form.  It  is  also  thought  that  in  some 
cases  a  poisonous  liquid  is  contained  in  the  spine. 

The  larvae  of  other  forms  have  the  habit  of  forming  dense 
webs,  more  or  less  baglike,  for  common  habitation  by  a  great 
number  of  caterpillars,  and  they  afterwards  spin  their  cocoons 
inside  these  receptacles.  This  has  been  ascertained  to  occur  in 
the  case  of  several  species  of  the  genus  Aiutplie,  as  has  been 
described  and  illustrated  by  Dr.  Fischer,1  Lord  Walsiugham,2  and 
Dr.  Holland.3  The  structures  are  said  to  be  conspicuous  objects 
on  trees  in  some  parts  of  Africa.  The  common  dwelling  of  this 
kind  formed  by  the  caterpillars  otHypsoidcs  radama  in  Madagascar 
is  said  to  be  several  feet  in  length  ;  but  the  structures  of  most 
of  the  other  species  are  of  much  smaller  size. 


1   Iln-Iiii.  cnt.  Zeitschr.  xxvii.  1883.  p.  9. 
2   7>.  Linn.  Soc.  ser.  2.  ii.  1885,  \>.  421.  3  Psyche,  vi.  1893,  p.  385. 


vi  MOTHS EUPTEROTIDAE PEROPHORIDAE  377 


The  larvae  of  the  South  American  genus  Pahistra,  though 
hairy  like  other  Eupterotid  caterpillars,  are  aquatic  in  their 
habits,  and  swim  by  coiling  themselves  and  making  movements 
of  extension ;  the  hair  on  the  back  is  in  the  form  of  dense 
brushes,  but  at  the  sides  of  the  body  it  is  longer  and  more 
remote  :  when  the  creatures  come  to  the  surface — which  is  but 
rarely — the  dorsal  brushes  are  quite  dry,  while  the  lateral  hairs 
are  wet.  The  stigmata  are  extremely  small,  and  the  mode  of 
respiration  is  not  fully  known.  It  was  noticed  that  when 
taken  out  of  the  water,  and  walking  in  the  open  air,  these 
caterpillars  have  but  little  power  of  maintaining  their 
equilibrium.  They  pupate  beneath  the  water  in  a  singular 
manner  :  a  first  one  having  formed  its  cocoon,  others  come  suc- 
cessively and  add  theirs  to  it  so  as  to  form  a  mass.1  Another 
species  of  P/dnstra,  P.  ljunneisteri ,  Berg,2  is  also  believed  to 
breathe  by  means  of  air  entangled  in  its  long  clothing ;  it 
comes  to  the  surface  occasionally,  to  renew  the  supply ;  the 
hairs  of  the  shorter  brushes  are  each  swollen  at  the  extremity, 
but  whether  this  may  be  in  connexion  with  respiration  is  not 
known.  This  species  pupates  out  of  the  water,  between  the 
leaves  of  plants. 

Di/jili  i/i  tarquinia  is  remarkable  on  account  of  the  great 
difference  of  colour  and  appearance  in  the  two  sexes.  In  the 
Australian  genus  Marane  the  abdomen  is  densely  tufted  at  the 
extremity  with  hair  of  a  different  colour. 

Fam.  8.  Perophoridae. — The  moths  of  the  genus  Peropliora 
have  for  long  been  an  enigma  to  systematists,  and  have  been 
placed  as  abnormal  members  of  Psychidae  or  of  Drepauidae, 
In  it  Packard  now  treats  them  as  a  distinct  family.  The  larvae 
display  no  signs  of  any  social  instincts,  but,  on  the  contrary,  each 
one  forms  a  little  dwelling  for  itself.  Some  twenty  species  of 
!'•  i-ujilnn'ii  are  now  known;  they  inhabit  a  large  part  of  the 
Xew  World,  extending  from  Minnesota  to  Buenos  Aires.  The 
habits  of  P.  melslieimeri  have  been  described  by  Harris, 
Packard  ''  and  Xewman,  and  those  of  P.  batesi  by  Xewrnan.4  The 
larva  is  very  peculiar  ;  there  is  a  flexible  pair  of  appendages  on  the 

1  Bar  and  Laboulbene,  Ann.  Soc.  ent.  France,  (v. )  iii.  1873,  p.  300. 
-  "r  ••>>.    ."'  .  vii.  1877,  p.  181  ;  and  Ent.  Zeit.  Mett-in,  xxxix.  1878,  p.  221  ;  and 
xliv.  1883,  p.  402. 

3  Ami.  New  }~«rk  Ac.  viii.  1893,  p.  48. 

4  Tr.  cat.  Soc.  Loitdu/i,  n.s.  iii.  1854,  p.  1. 


3/8  LEPIDOPTERA  CHAP. 

head,  the  use  of  which  is  unknown  ; 1  they  arise  by  slender  stalks 
behind  and  above  the  eyes,  are  about  as  long  as  the  head,  and 
are  easily  broken  oft'.  After  hatching,  the  young  larva,  when  it 
begins  to  feed,  fastens  two  leaves  together  with  silk  threads,  and 
so  feeds  after  the  fashion  of  a  Tortricid,  rather  than  a  case-making, 
larva.  Subsequently,  however,  the  caterpillar  entirely  detaches 
two  pieces  of  leaves  and  fastens  them  together  at  the  edges,  thus 
constructing  a  case  that  it  lives  in,  and  carries  about ;  it  can 
readily  leave  the  case  and  afterwards  return  to  it.  When  at 
rest,  the  larva  relieves  itself  from  the  effort  of  supporting  this 
case  by  the  device  of  fastening  it  to  a  leaf  with  a  few  silken 
threads  ;  when  the  creature  wished  to  start  again,  "  it  came  out 
and  bit  off  these  threads  close  to  the  case."  Subsequently  it 
changes  inside  the  case  to  a  pupa  armed  with  transverse  rows  of 
teeth,  like  so  many  other  pupae  that  are  capable  of  a  certain 
amount  of  movement.  The  larva  is  of  broad,  short,  peculiar 
form,  and  is  said  to  be  very  bold  in  defending  itself  when  at- 
tacked. The  moth  is  somewhat  like  the  silkworm  moth,  though 
df  a  more  tawny  colour.  Newman  does  not  allude  to  any 
cephalic  appendages  as  existing  in  the  larva  of  P.  batesi. 
If  we  accept  the  eggs  figured  and  described  by  Snellen,2  as  those 
of  P.  Itatesi,  it  is  possible  that  this  Insect  possesses  a  peculiar 
mode  of  oviposition,  the  eggs  being  placed  one  on  the  other,  so 
as  to  form  an  outstanding  string ;  but  we  think  this  example 
probably  abnormal;  the  mode  is  not  shared  by  P.  mclsheimcri. 
The  genus  Lacosoma  is  considered  by  Packard  to  be  an  ally  of 
rr/'iiji/toi-tt.  The  caterpillar  of  L.  chiridota  doubles  a  leaf  at  the 
mid-rib  and  fastens  the  two  edges  together,  thus  forming  an  un- 
symmetrical  case.  Many  larvae  of  Microlepidoptera  do  something 
like  this,  but  the  Lacosoma  cuts  off  the  habitation  thus  formed  and 
carries  it  about.  Packard  says  it  may  have  descended  from 
ancestors  with  ordinary  habits  and  that  certain  peculiar  obsolete 
markings  oil  the  body  of  the  caterpillar  may  be  indications  of  this.3 
The  Argentinian  Insect  Mam  illo  curtisea  4  is  also  probably  an  ally 

1  Dyar  says,  "We  may  surmise  that  it  is  to  present  a  terrifying  appearance  to- 
ward small  enemies."  He  calls  the  Insect  both  Perophora  and  Cicinnus,  melshei- 
•uti'i'i,  and  states  that  it  belongs  [according  to  the  larva]  to  Tineidae  ;  the  appendages 
he  considers  to  be  enormously  developed  setae.  /.  X.  )'ork  ent.  Soc.  iv.  1896,  p.  92. 

:    TijJs^tr.  Ent.  xxxviii.  1895,  p.  56,  PI.  4. 

3  Ann.  X<:v  York  Ac.  viii.  1893,  p.  48. 

4  Weyenbergh,  Tijdschr.  Ent.  xvii.  1874,  p.  220,  PL  xiii. 


VI 


HETEROCERA — PEROPHORIDAE 


379 


of  Lacosoma.  The  caterpillar  of  this  moth  spins  a  dwelling 
for  itself,  and  is  remarkable  from  the  bright  colour  of  the 
thoracic  segments,  the  following  somites  being  colourless ;  the 
head  bears  a  pair  of  large  processes,  quite  different  from 
those  figured  bv  Harris.  The  moth  itself  is  very  Geometric!- 

.~*  i/  «• 

like  in  colour  and  form.      This  species  is  now  assigned  to  Pero- 


FIG.  188.  —  Larvae  of  Hammock-moth,   Perophora  sanguinolenta,  projecting  from 
Hammocks,  built  from  their  o\vu  excrement.     South  America.     (After  Jones.) 


•/i/mrrt,  but  it  seems  to  be  very  doubtful  whether  many  of  the 
species  placed  in  this  genus  really  belong  to  it.  The  diversity 
of  habits  and  instincts  evinced  by  these  moths  of  exceptional 
modes  of  life,  but  considered  to  be  closely  allied,  is  very  interest- 
ing. The  most  remarkable  of  all  is  the  Hammock-moth,  Pero- 
phora sanguinolenta,  of  the  centre  of  South  America,  the  larva  of 
which  constructs  its  portable  habitations  out  of  its  own  excre- 


38o 


LEPIDOPTERA 


CHAP. 


ment,  which  is  of  peculiar  form,  specially  suitable  for  the 
purpose.  The  caterpillar,  when  wishing  to  enlarge  its  case,  builds 
it  up  from  excrement  "  flattened  at  the  sides,  so  as  to  adapt  it 
for  building  purposes." 

Fam.  9.  Sphingidae  (Hawk  -moths}.  —  A  very  important 
family  of  moths  of  large  or  moderate  size.  They  have  a  pro- 
boscis which  is  frequently  very  long  ;  there  is  a  frenulum  ;  the 
body  is  stouter  than  in  most  other  Lepidoptera,  and  the  wings 
are  of  small  superficies  in  comparison  with  it  ;  the  antennae  are 
somewhat  peculiar,  having  a  thick,  solid  appearance,  pointed  at 
the  tip.  This  is  usually  somewhat  hooked,  and  bears  a  few  hairs. 
In  the  males  the  antennae  are  formed  in  a  manner  specially 
characteristic  of  the  family.  In  section,  each  joint  shows  a 
chitinous  process  on  the  under  side  (Fig.  189,  A),  forming  with 
that  of  the  other  joints  a  continuous  ridge,  and  on  each 

Fie.  189.  —Antennae 
of  Sphingidae.  A, 
One  joint  of  an- 

tenna      Of       (.'ItlH-fll- 

caiiijin  >•!  ft'  inn-  $, 
enlarged  ;  B,  three 
joints  of  antenna  of 


seen  from  one  side, 
and  enlarged. 


side  of  this  ridge  there  exists  a  series  of  short,  delicate  "  cilia  " 
arranged  in  a  very  beautiful  manner  (Fig.  189,  B).  This  structure, 
with  some  modifications,  appears  to  be  usually  present  in  the 
family  ;  it  attains  a  very  perfect  development  in  cases  where 
the  tips  of  two  rows  of  cilia  bend  towards  one  another,  meeting 
so  as  to  form  an  arched  cavity.  This  structure  is  different  from 
what  occurs  in  the  males  of  other  families  of  Lepidoptera,  for 
though  cilia  are  very  common,  they  are  usually  placed  either  on 
two  projections  from  the  body  of  the  antennae  (instead  of  on  the 
two  sides  of  a  single  projection),  or  there  is  but  a  single  whorl,  or 
set,  of  them  on  each  joint  (Catoccda,  etc.).  The  front  wings  are 
usually  pointed  at  the  tip,  and  are  long  in  proportion  to  their 
width:  but  in  the  Smerinthini  they  are  of  different  form,  with 
the  outer  margin  scalloped  ;  the  hind  wings  are  remarkably 
small  :  the  abdomen  is  frequently  pointed,  but  in  the  Macro- 
glossini,  or  Humming-bird  hawk-moths,  it  is  furnished  at  the 

1  Jones.  P.  Liverpool  Hoc.  xxxiii.  1879,  \>.  Ixxvii. 


VI 


HETEROCERA HAWK-MOTHS 


tip  with   a   tuft,  or  with  two  tufts,  of  dense,  long  scales,  capable 
of  expansion. 

The  larvae  are  remarkable  for  their  colours  and  form.  The 
anterior  segments  are  attenuated,  but  are  capable  of  great  retrac- 
tion, so  that  in  repose  (Fig.  190,  A)  this  shape  is  concealed  by 
the  curious  attitudes  that  are  assumed.  There  is  in  nearly 
all  cases  a  conspicuous  horn  on  the  eleventh  segment,  and  the  body 
at  the  extremity  behind  the  horn  is  so  much  modified  that  the 
terminal  two  segments  look  like  little  more  than  a  pair  of  large 
claspers.  In  the  Choerocampini,  the  thoracic  segments  are 
retractile,  and  can  be  withdrawn  into  the  more  or  less  inflated 
fourth  segment,  and  give  the  creature  somewhat  the  appearance 


FIG.  190.— Larva  of 
the  Poplar  Hawk- 
inoth,  Smerinthits 
populi.  x  1.  A, 
in  repose  ;  B,  iu 
movement. 


of  a  miniature  hooded  snake.  The  larvae  of  Sphingidae  do  not 
bear  any  conspicuous  hairs — except  during  the  first  instar.  They 
do  not  spin  cocoons,  but  bury  themselves  in  the  earth.  The 
pupa  is  remarkable  from  the  deep  cleft  that  exists  to  admit  air 
to  the  first  spiracle,  and  for  a  deep  depression  on  each  side  of  the 
anterior  part  of  abdominal  segments  5-7  ;  in  some  cases  the 
proboscis  projects  on  the  breast  somewhat  like  the  handle  of  a 
pitcher. 

A  great  deal  has  been  written  on  the  colours,  markings,  and 
attitudes  of  Sphingid  larvae,  and  many  interesting  facts  h;i\c 
been  brought  to  light.  We  may  refer  the  reader  to  the  writings 
of  Weismann J  and  Poulton,2  without,  however,  recommending 
him  to  place  an  implicit  confidence  in  their  somewlmt 
metaphysical  disquisitions ;  for  the  views  there  shadowed  will 

1  Studies  in  the  Theory  of  Descent,  part  2,  London,  1881. 
1   Tr.  ent.  Soc.  London,  1885  and  1886. 


382  LEPIDOPTERA  CHAP. 


necessarily  became  much  modified  with  the  advance  of  exact 
knowledge.  It  is  certain  that  the  position  assumed  by  the  same 
individual  varies  much  according  to  age,  and  to  the  interval 
since  the  last  moult ;  sometimes  the  attitude  is  much  more  remark- 
able than  that  shown  in  Figure  190,  A,  for  the  anterior  seg- 
ments are  held  erect,  as  well  as  contracted,  the  front  part 
of  the  body  being  curled,  and  the  Insect  supported  by  the 
claspers  and  two  pairs  only  of  the  abdominal  feet.  There  is, 
too,  a  considerable  difference  in  colour  before  and  after  an 
ecdysis.  Piepers,  who  has  had  a  long  experience  among  Sphingid 
larvae  in  Java,  considers  that  much  of  what  has  been  written  as 
to  the  protective  value  of  their  colours  and  attitudes,  is  mere 
fancy,  and  wild  generalisation.1 

Sphingidae  have  been  recorded  as  capable  of  producing  sounds 
in  the  larval  and  pupal,  as  well  as  in  the  perfect,  instars ;  but 
the  method  in  which  this  is  done  has  not  been  ascertained, 
except  in  the  case  of  the  imago  of  the  Death's-head  moth, 
which  is  well  known  to  emit  a  very  audible  cry  when  not  on  the 
wing;  in  this  case  it  is  highly  probable  that  the  method  is  the 
friction  of  the  palpi  against  the  proboscis,  as  stated  by  Reaumur 
and  Landois  ;  the  inner  face  of  the  palp  is  said  to  be  marked  in 
this  case  with  fine  ridges  or  striae. 

Fam.  10.  Cocytiidae. — A  single  genus  constitutes  this  family, 
and  there  are  only  three  or  four  species  known  ;  they  come  from 


FIG.  191. — Cocytin  i/ni-rillii.     New  Guinea.      (After  BoisJuval. ) 

the    region    of  Xew   Guinea,   whence   the    first   was    brought    by 

D'Urville   nearly  a  hundred   years  ago.      They  are   still  amongst 

1   Tijdschr.  Ent.  xl.  1897,  pp.  127-103,  4  plates. 


VI 


HETEROCERA COCYTIIDAE NOTODONTIDAE 


333 


the  rarest  of  Insects.  Nothing  is  known  as  to  their  life-histories. 
In  appearance  they  somewhat  remind  us  of  the  Bee-hawk  moths  and 
Zygaenidae.  Butler  says  l  the  family  is  characterised  by  the  palpi, 
which  differ  much  in  the  two  sexes,  and  by  the  antennae  resem- 
bling those  of  Castniidae  or  Hesperiidae.  The  form,  transparency, 
and  coloration  of  the  wings  reminds  one  vividly  of  the  Sphingid 
genus  Hemaris ;  the  nervuration  is  somewhat  like  that  of  Hemaris, 
but  has  certain  features  of  Zygaenidae.  Butler  places  the  family 
between  Agaristidae  and  Zygaenidae. 

Fam.  11.  Notodontidae  (Prominents,  Puss-moths,  etc.).- — This 
is  one  of  the  most  extensive  of  the  families  of  Bombyces ;  it  con- 
sists in  larger  part  of  obscure-coloured  moths,  somewhat  like  the 
ordinary  Noctuidae  of  temperate  regions ;  to  which  family  the  ISToto- 
donts  are  indeed  considered  to  be  very  closely  allied.  The  family 
contains,  however,  some  very  remarkable  forms.  Tarsolepis  has 
an  elongate  body, 
terminated  (in  the 
female  of  T.  ful- 
!  I  a  i- if  era)  by  a  very 
conspicuous  tuft 
of  enormously 
long,  battledore 
scales ;  while  in 
the  male  of  T. 
sommeri  the  hind 
legs  are  provided 
with  an  append- 
age of  beautiful, 
roseate  hairs.  A 
few  of  the  larger 
kinds  bear  a  con- 
siderable resem- 
blance in  form  and 

proportions  to  the  Sphingidae.  Some  of  the  larvae  are  most  inter- 
esting objects  ;  the  Puss-moth  caterpillar,  the  Lobster,  and  t he- 
Dragon  larvae  are  of  such  strange  forms  that  they  have  already 
interested  several  generations  of  observers.  The  Puss-moth  is 
common  in  the  southern  half  of  England  ;  its  caterpillar  (Fig.  192) 
has,  instead  of  the  claspers,  a  pair  of  tubes  in  which  are  concealed 

1    Tr.  ent.  £>'oc.  London,  1884,  p.  351. 


FIG.  192. — Centra  vinitJa  (Pnss-moth)  caterpillar.     A,  Moult- 
ing ;  B,  the  same  individual  a  i'e\v  hours  after  the  moult. 


384  LEPIDOPTERA  CHAP. 

two  long,  flexible  whips,  capable  of  being  thrust  out,  and  with- 
drawn, with  rapidity.  The  structure  and  the  mode  of  action  of 
these  flagella  have  been  well  elucidated  by  Professor  Poulton.1 
The  flagella  are  to  be  considered  as  actual  prolongations  of  the 
receptacle  in  which  each  is  placed,  though  they  are  of  very 
different  texture  therefrom  ;  they  are  everted  by  blood-pressure 
and  drawn  in  by  muscular  action  ;  this  latter  function  is  very 
perfectly  accomplished,  the  amount  of  relaxation  and  contraction 
of  the  muscle  being  very  great.  It  has  been  maintained  that 
the  whips  have  arisen  as  arms  of  protection  against  the  attacks 
of  Ichneumon  flies ;  observation  shows,  however,  that  the  pro- 
portion of  these  "  protected  "  Insects  destroyed  by  enemies  of  this 
sort  is  quite  as  large  as  it  is  in  the  case  of  forms  that  are  not  so 
protected.  The  Puss-moth  larva  is  also  believed  to  be  protected 
by  terrifying  attitudes,2  as  well  as  by  ejection  (like  so  many  other 
larvae  and  insects  generally)  of  fluid.  There  is  no  reason  for 
believing  that  these  larvae  are  less  eaten  than  others,  and  con- 
sequently a  further  hypothesis  has  been  proposed,  to  the  effect 
that  if  they  had  not  acquired  these  means  of  defence  they  would 
have  been  exterminated  altogether.  This  supposition  is  con- 
sidered to  account  for  their  acquiring  the  defence  by  means  of 
natural  selection ;  realising  the  dictum  of  D.  O'Phace,  Esq.— 

Some  flossifers  think  that  a  fakkilty's  granted, 
The  ininnit  it's  proved  to  be  thoroughly  wanted. 

When  the  Puss-moth  caterpillar  is  full  grown  it  spins  a  peculiar 
cocoon  of  a  solid  and  impervious  nature,  which  it  manages  to  make 
look  very  like  the  spots,  crevices,  or  other  places  amongst  which 
it  is  located ;  in  this  prison  the  creature  remains  fur  nine  or  ten 
months — by  far  the  larger  part  of  its  existence.  When  it  has 
changed  to  a  moth  it  has  to  escape  from  the  cell  in  which  it  so 
effectually  confined  itself.  This  is  effected  by  the  cocoon  being 
tli inner  in  front  of  the  head  of  the  moth,  and  by  the  emission 
from  the  alimentary  canal  of  a  fluid  that  softens  the  cocoon  at 
the  spot  alluded  to.  Mr.  Latter  has  ascertained  3  that  this  fluid 
is  strongly  alkaline,  and  contains  potassium  hydroxide.  The 
front  of  the  head  of  the  moth  is  provided  with  a  shield,  consist- 
ing of  a  portion  of  the  pupa  shell,  which  enables  the  moth  to 

1  Tr.  ent.  Soc.  London,  1887,  p.  297,  PI.  x. 
2  See  Poulton,  Tr.  cut.  Soc.  London,  1886,  etc.      3  Op.  tit.  1895,  p.  399. 


vi  HETEROCERA — NOTODONTIDAE  385 

push  through  in  safety,  and  at  the  same  time  protects  the  head 
from  the  emitted  fluid.  Figure  192  shows  the  great  change  that 
occurs  in  the  period  of  a  few  hours  in  the  size  of  the  head  of  the 
larva,  as  well  as  in  that  of  the  spiracles :  in  A  the  old  spiracles 
are  seen  surrounded  by  the  much  larger  new  orifices,  which  are 
at  the  moment  of  moulting  quite  visible  through  the  skin  that  is 
about  to  be  cast  off. 

The  caterpillar  of  the  Lobster-moth,  Stauropus  fayi,  is  more 
remarkable  than  that  of  the  Puss-moth,  but  is  unfortunately 
very  rare.  It  has  remarkably  long  thoracic  legs,  the  abdomen  is 
swollen  at  the  tip,  and  instead  of  the  terminal  claspers  has  two 
long  slender  processes.  The  effect  of  these  peculiarities  is  greatly 
enhanced  by  the  extraordinary  attitude  assumed  by  the  cater- 
pillar, which  holds  the  first  five  segments  erect,  with  the  second 
and  third  pairs  of  thoracic  legs  outstretched  ;  the  swollen  terminal 
segment  is  also  held  erect.  Hermann  Muller  states  l  that  when 
seen  from  the  front  this  caterpillar  looks  like  a  spider,  and  also 
that  when  alarmed  it  moves  the  long  legs  after  the  fashion  of 
an  Arachnid.  He  believes  that  it  is  thus  effectually  protected 
from  the  attacks  of  Ichneumons.  Birchall  says  2  that  the  young- 
larva,  when  at  rest,  closely  resembles,  in  colour  and  outline, 
one  of  the  twigs  of  beech  with  unopened  buds,  on  which  it 
frequently  stations  itself;  and  that,  when  feeding,  its  likeness 
to  a  great  earwig  or  to  a  8ta})hylinus  is  very  striking.  Others 
say  that  this  caterpillar  resembles  a  dead  and  crumpled  beech 
leaf. 

The  larva  of  Hybocampa  milhauseri — the  Dragon  of  old  Sepp 
—is  highly  remarkable.  When  young  it  has  grand  lateral 
horns  in  front,  and  a  dorsal  row ;  as  it  grows  the  lateral 
horns  disappear.  Dr.  Chapman  says  3  that  he  could  not  under- 
stand at  first  why  any  larva  should  have  such  remarkable  angular 
outlines,  curiously  conspicuous  corners  and  humps.  But  he  after- 
wards found  that  the  creature  exactly  resembled  a  curled  oak 
leaf,  eaten  and  abandoned  by  a  Tortrix  larva.  This  caterpillar 
also  constructs  an  elaborate  cocoon  from  which  the  moth  escapes 
by  an  operation  performed  by  the  pupa,  which  is  provided  with 
two  hard  spines,  called  by  Dr.  Chapman  sardine-openers.  "  By 
a  lateral  rotatory  movement  of  the  pupa,  which  obtains  its  fulcrum 

1  P.  eat.  Sue.  London,  1880,  p.  iii.  -  Ent.  Monthly  May.  xiii.  1877,  p.  231. 

3  Entomologist,  xxiii.  1890,  p.  92. 
VOL.   VI  2   C 


386  LEPIDOPTERA 


CHAP. 


from  the  tightness  with  which  it  is  grasped  by  the  cocoon,  it 
traverses  over  and  over  again  "  the  same  part  of  the  cocoon  till 
it  is  cut  through  ;  at  the  same  time  the  spines  act  as  guides  to 
a  fluid  which  is  emitted  so  as  to  soften  the  part  that  has  to  lie 
sundered. 

Though  many  other  larvae  of  Xotodontidae  are  of  most 
curious  form  and  assume  remarkable  attitudes,  yet  this  is  not 
the  case  with  all,  and  some  are  quite  ordinary  and  like  the  cater- 
pillars of  common  Xoctuidae.  This  is  the  case  with  the  species 
Rlicgmatophila  alpina  we  have  selected  to  illustrate  the  meta- 
morphosis of  the  Order  (Fig.  157).  Those  who  wish  to  form  an 
idea  of  the  variety  of  larval  forms  in  this  family  will  do  well 
to  refer  to  Packard's  beautiful  volume  on  the  Xorth  American 
forms.1  The  family  has  a  very  wide  distribution,  but  is  absent 
from  Xew  Zealand  and  Polynesia,  and  appears  to  be  but  poorly 
represented  in  Australia.  In  Britain  we  have  about  two  dozen 
species. 

Fam.  12.  Cymatophoridae. — A  small  family  of  nocturnal 
-noths  that  connect  the  Bombyces  with  the  X1  octuids ;  they  are 
usually  associated  with  the  latter,  but  are  widely  separated  in 
Hampson's  arrangement  because  of  a  slight  difference  of  nervura- 
tion,  nervule  5  being  nearer  to  6  than  to  4,  whereas  in  Xoctuidae 
the  reverse  is  the  case.  The  Insects,  however,  in  certain  respects 
approach  the  Xotodontidae,  and  are  of  interest  if  only  as  showing 
that  the  linear  sequences  we  adopt  in  books  are  necessarily  con- 
ventional, and  to  some  extent  deceptive.  We  have  three  genera 
in  Britain  ;  our  pretty  Peach-blossom,  Tkyatira  batis,  and  the  very 
different  Buff-arches,  T.  derasa,  being  among  them.  Meyrick 
denies  any  connexion  of  this  group  with  Xoctuidae,  and  in  his 
nomenclature  Cymatophora  becomes  Polyploca,  and  the  family, 
consequently,  Polypi ocidae. 

Fam.  13.  Sesiidae  or  Aegeriidae  (Clear-lyings'). — A  family 
of  comparatively  small  extent ;  its  members  have  frequently  one 
or  both  pairs  of  wings  in  large  part  free  from  scales,  the  tip  of 
the  body  tufted,  the  hind  legs  of  one  sex  peculiar.  The  size  is 
usually  small,  but  in  the  largest  forms  the  measurement  may  be 
but  little  less  than  two  inches  across  the  expanded  wings. 
The  pupa  is  of  the  kind  classed  as  "  incompletae  "  by  Chapman, 
the  appendages  not  being  firmly  glued  to  the  body,  and  much 

1  Mem.  Ac.   IJ'ashinyton,  vii.  1895,  290  pp.,  49  plates. 


VI 


HETEROCERA — SESIIDAE TINAEGERIIDAE 


337 


mobility  existing ;  an  "  eye-collar  "  is  present,  and  the  segments 
of  the  abdomen  are  armed  with  series  of  teeth.  The  larva 
is  a  concealed  feeder,  nearly  naked  and  colourless,  but  with 
the  legs  normal  in  number — three  thoracic,  four  abdominal  pairs 
of  feet,  and  the  terminal  claspers ;  these  are  sometimes  but 
poorly  developed ;  the  larvae  have  a  greater  or  less  resemblance 
to  those  of  Longicorn  beetles,  the  habits  of  which  they  share.  The 
family  was  formerly  associated  with  the  Sphingidae,  with  which 
it  has  no  true  relationship ;  it  is  more  closely  allied  to  the 
Tineidae.  Some  of  the  species  have  a  certain  resemblance  to 
Hymenoptera,  which  is  probably  in  most,  if  not  in  all  cases 
merely  incidental.  The  proper  position  of  the  family  was  pointed 
out  by  Butler,1  but  he  did  not  distinguish  it  from  Tinaegeriidae. 
Meyrick  calls  the  family  Aegeriadae,  and  places  it  in  his  series 
Tineina. 

We  have  two  genera  of  these  Clear -wings  in  Britain. 
They  are  Trocliilium  (called  variously  Sesia,  S-plti:<'i<',  and 
Aegeria),  with  two  species  of  comparatively  large  size,  and 
(called  variously  Trocliilium  and 
Aegeria),  with  nearly  a  dozen  species 
of  smaller  size.  A  third  genus, 
Sciapteron,  is  doubtfully  native  with 
us.  They  are  much  prized  by  col- 
lectors on  account  of  the  rarity  of 
the  Insects  and  their  great  differ- 
ence in  appearance  from  our  other 
native  Lepidoptera. 

Fam.  14.  Tinaegeriidae. — This 
is  one  of  the  least  known  of  the 
families  of  Lepidoptera,  and  has  only 
recently  been  distinguished  from 
Sesiidae.  It  is  entirely  exotic,  and 
our  knowledge  of  it  is  principally  FIG. 

.f  i-  Africa.     (After  Walsingham.) 

due  to  Lord  Walsingham.-    Nothing 

is  known  as  to  the  life-histories,  except  that  it  has  been  stated 
by  Staintoii  that  a  larva  feeds  in  webs  on  shoots  of  a  shrub  of 
the  genus  Clerodendron.  The  family  is  widely  distributed,  but 
its  metropolis  will  probably  prove  to  be  the  tropics  of  Africa.  It 
is  of  considerable  interest  as  showing  that  the  Sesiidae  really 
1  Tr.  cat.  Soc.  London,  ]878,  p.  121,  PI.  v.  "  Op.  cit.  1SS9,  pp.  1-40,  6  plates. 


388  LEPIDOPTERA 


CHAP. 


belong  to  the  Tineid  series  of  moths.  '  The  species  we  figure  (Fig. 
193)  has  a  character  otherwise  peculiar  to  Sesiidae  in  the  wings 
being  inserted  011  the  thorax  remote  from  the  head — a  feature  we 
do  not  find  in  the  Tineidae  proper ;  while  on  the  other  hand  it 
has  the  lung  wing-fringes,  and  the  shape  of  the  wings  that  are 
characteristic  of  Tineidae.  It  is  worth  mentioning  that  though 
these  Insects  are  of  excessive  rarity  and  very  peculiar,  there  exists 
in  the  Solomon  Islands  l  a  species  distinct  from,  though  at  first 
sight  excessively  similar  to,  the  S.  African  one  we  figure. 

Fam.  15.  Syntomidae. — This  family  has  usually  been  asso- 
ciated with  the  Zygaenidae.  It  includes  a  large  number  of 
moths  having,  as  a  rule,  in  external  appearance  little  to  distin- 
guish them  from  the  family  named.  Many  of  them  are  of  gaudy 
colours,  and  probably  of  diurnal,  but  somewhat  sedentary,  habits. 
The  wings  are  less  ample  than  usual,  the  hind  pair  frequently 
very  small,  so  that  the  Insects  have  somewhat  the  proportions  of 
Hymenoptera.  In  some  cases  the  resemblance  is  made  more 
remarkable  by  the  fact  that  the  wings  are  transparent  and  bare 
of  scales,  or  have  scales  only  at  the  margins,  so  as  to  be  like  the 
wings  of  Hymenoptera.  Not  less  remarkable  is  the  fact  that 
these  Insects  use  the  body  itself  for  the  purposes  of  adornment 
or  display ;  thus  adopting  a  system  prevalent  in  the  Hymenop- 
tera, rather  than  that  of  their  own  Order,  where  the  rule  is  that 
the  wings  are  more  ornamented  than  the  body.  In  many 
cases  the  shape  of  the  body  is  so  very  different  from  the  normal 
that  the  disposition  of  the  organs  of  life  in  the  interior  of  the 
body  must  be  materially  affected.  In  some  genera,  such  as  Andre- 
nimorpha,  the  form,  colour  and  attitude  of  the  body  and  some 
of  the  limbs  are  plainly  similar  to  Hymenoptera.  These  Insects 
have  a  highly-developed  frenulum,  retinaculum,  and  proboscis ; 
bipectinate  antennae  in  the  male,  a  complex  organ  at  the  base 
of  the  abdomen  on  each  side,  and  are  in  fact  highly-developed 
forms,  except  perhaps  as  regards  the  structures  in  connexion 
with  flight. 

Unfortunately  little  or  nothing  is  known  as  to  the  habits 
and  metamorphoses  of  these  extraordinary  creatures,  but  it  is  no 
doubt  to  them  Seitz  referred  in  saying,  "  How  far  one  may  be 
deceived  by  appearances  of  a  mimetic  nature  can  only  be  com- 
prehended by  visiting  the  tropics;  in  this  part  of  the  world 

1    \Valsinghaui,  Op.  at..  1839.      c.  p.  21. 


vi  SYNTOMIDAE MIMICRY  389 


[Europe]  one  is  prepared  by  knowledge  gained  from  books  for 
the  appearance  Sesia  presents.  Had  one  no  knowledge  of  this 
sort  as  to  Sesiidae  he  would  actually  in  the  field  [in  Brazil]  over- 
look dozens  of  these  little  creatures  without  being  aware  of  his 
deception.  The  surprise  at  finding  a  quite  different  being  in  the 
net  from  what  one  believes  he  has  caught  occurs  daily  in  Brazil, 
so  rich  in  Lepidoptera."  The  same  intelligent  observer  says 2 
that  a  species  of  Macrocneme  was  observed  by  him  to  be  exactly 
like  one  of  the  blue  wasps  of  the  genus  Pepsis. 

One  remarkable  point  in  these  Hyrnenopteroid  Syntomids 
is  their  complete  dissimilarity  from  their  immediate  allies. 
They  resemble  very  different  Hymenoptera ;  and  not  only 
stinging  Hymenoptera ;  the  Sessiliventres  have  a  large  share 
of  their  attentions ;  the  numerous  species  of  Dycladia  partaking 
the  appearance  of  the  South  American  Sawflies  in  a  wonderful 
manner.  Bees,  Wasps  of  the  most  different  kinds,  and  a  variety 
of  Sawflies  are  beautifully  paralleled,  if  one  may  use  such  an 
expression,  by  these  Syntomids.  That  shown  in  Fig.  194  has  the 
abdomen  formed  like  that  of  a  Petiolate  Hymenopteroii ;  the 
base  of  this  part,  moreover,  resembles  in  a  remarkable  manner 
the  "  median  segment  "  of  that  Order.  The  constriction  is,  how- 
ever, placed  not  at  the  base  of  the  abdomen  but  beyond  the  second 
segment.  Thus  the  structure  is  not  morphologically  similar  to 
that  of  the  Hymenoptera,  for  the  median  segment  of  Aculeate 
Hymenoptera  consists  of  only  one  abdominal  segment,  while  in 
this  moth  the  corresponding  part  is  formed  of  two  segments. 
Though  anatomically  inexact,  the  resemblance  is,  as  to  propor- 
tions, correct ;  and  those  who  delight  in  the  use  of  the  imagination 
will  see  that  had  the  moth  used  only  one  segment  for  the  imita- 
tion, the  result  would  have  been  less  successful  owing  to  insufficient 
size.  In  his  very  interesting  account  of  some  Brazilian  Syn- 
tomids,3 Seitz  describes  a  species  of  Trichura  provided  with  a 
long  appendage  that  is  held  straight  backwards  during  life ; .  and 
he  informs  us  that  this  creature  resembles  a  female  Ichneumon, 
the  long  process  looking  like  the  elongate  ovipositor  of  the 
Hymenopteron.  Possibly  the  species  from  Demerara  we  figure 
may  resemble  an  Ichneumon  we  are  not  acquainted  with,  though 
its  colour  and  form  rather  suggest  a  likeness  to  an  Aculeate. 

1  Ent.  Zcit.  Stettin,  Ivi.  1895,  p.  233.  -  Op.  tit.  li.  1890,  p.  261. 

3  Ent.  Zcit.  Stettin,  li.,  1890,  p.  263. 


390  LEriDOPTERA  CHAP. 

This  case  of  resemblance  is  of  the  most  noteworthy  character, 
for  an  appendage  of  this  kind  in  a  Lepidopterous  Insect  is 
without  parallel,  and  is  almost  equivalent  to  the  production  of 
a  new  structure.  An  interesting  feature  of  the  case  is  that 

O 

Ichneumonidae  do  not  sting,  and  there  is  no  evident  reason  why 
the  enemies  of  the  moth  should  be  particularly  afraid  of  an 
ovipositor. 

The  larvae  appear  to  be  in  form  somewhat  like  those  of 
Zygaenidae  ;  but  with  the  same  sort  of  remarkable  clothing,  in 
the  form  of  tufts  and  brushes,  that  we  find  in  Lymantriidae.  A 


FIG.  194. — Trichura,  sp.   x  j.     Demerara. 

cocoon  is  formed.  In  Britain  no  member  of  this  family  is  to 
be  met  with,  but  Nudia  ancilla  may  formerly  have  been  a 
native;  Syntomis  phegea  has  occurred  here;  probably  an  escaped 
example  that  had  been  introduced  in  one  of  its  earlier  stages. 

Fam.  16.  Zygaenidae  (-Bur net-Moths). — This  family  is  one 
about  the  limits  and  characters  of  which  much  difference  of 
opinion  prevails.  As  exemplified  by  our  Burnet- moths  it  is 
characterised  (in  addition  to  the  points  given  in  the  table)  by 
the  peculiar,  flexible  antennae;  these  are  a  little  thicker  before 
the  tip,  but  are  curved  and  pointed  at  the  extremity,  and  without 
pectinations  in  the  male.  There  is  an  elongate  proboscis ; 
1  dadder-like  organs  at  the  sides  of  the  first  abdominal  segment 
are  not  present.  The  pupa  is  softer  than  is  usual  in  the  Macro- 
lepidoptera,  and  the  parts  are  less  firmly  fixed  together,  so  that 
unusual  mobility  exists;  six  of  the  intersegment al  mrmbranes 


vi  HETEROCERA ZYGAENIDAE  391 

are  free,  and  the  abdomen  has  much  power  of  movement ;  there 
is  no  eye-collar ;  the  antennae,  hind  legs,  and  proboscis -tips 
stretch  backwards  as  far  as  the  fifth  or  sixth  abdominal  seg- 
ment, the  tips  being  quite  free ;  on  the  dorsal  plates  of  the 
abdomen  there  are  rows  of  minute  elevations  reminding  one  of 
the  teeth  existing  in  pupae  that  live  in  stems  or  galleries.  This 
is  altogether  a  peculiar  pupa  ;  it  lives  closely  enclosed  in  a  small 
hard  cocoon,  and  its  great  capacity  for  movement  is  perhaps  con- 
nected with  the  fact  that  the  pupa  itself  manages  to  force  its 
way  through  the  cocoon  in  anticipation  of  the  emergence  of  the 
moth.  This  cocoon  is  fastened  tightly  to  a  stem,  and  is  covered 
with  a  substance  that  gives  it  a  glazed  appearance.  The  larvae 
are  objects  of  a  baggy  nature,  with  inferior  coloration,  consisting 
of  large  dark  blotches  on  a  light  ground,  and  without  any 
remarkable  development  of  their  somewhat  feeble  system  of 
hairs.  Numerous  small  moths  from  the  tropics  are  assigned 
to  the  family ;  they  are  most  of  them  conspicuously  marked 
and  coloured,  and  like  our  Burnets  are  probably  diurnal. 

The  family  Chalcosiidae  is  reduced  by  Hampson  to  the 
position  of  a  sub-family  of  Zygaenidae.  It  consists  of  a  large 
variety  of  diurnal  moths  of  varied  and  brilliant  colours,  with  an 
expanse  of  wing  large  in 
comparison  with  the  typi- 
cal Zygaenae,  and  with 
the  antennae  pectinate  or 
flabellate  to  the  tip.  Some 
of  these  Insects  (which  are 
as  conspicuous  as  possible 

in  appearance,  at  any  rate  .  , ,    ~^r~   ""w. 

J  FIG.  195. — Hampsoma  putchermma.      Wings    on 

ill       a      Cabinet,      the       East  right    side    detached    and    denuded    to    show 

Indian      Cadphises     moorei          ^miration.      India.     (After  Swinhoe.) 

e.g.}  are  considered  to  be  destitute  of  any  special  "  protection." 
Histia-  is  a  genus  of  remarkable  cruciform  moths,  of  a  mixture 
of  black  and  metallic  colours,  with  carmine  -  tinted  bodies. 
Hu.mpsonict,  pulcherrima  (East  India)  is  a  curious  moth  of  butter- 
fly form  and  coloration,  red  and  black  with  yellow  patches,  and 
with  some  of  the  nervules  distorted,  as  if  they  had  been  forced 
a] tart  in  certain  spots  in  order  to  accommodate  these  patches. 

Two   or   three  hundred   species  of  Chalcosiidae  are  recorded. 
They  are  specially  characteristic  of  the  Indo-Malayan  region. 


392  LEPIDOPTERA  CHAP. 

Fam.  17.  Himantopteridae  (Thymaridae  of  some  autho- 
rities) are  placed  by  Hainpson  in  the  sub-family  Phaudinae  of 
Zygaenidae  characterised  by  the  absence  of  the  mouth-parts. 
The  Himantopteridae  are  small  moths,  and  have  the  scales  on 
the  wings  very  imperfect  and  hair-like;  the  hind  wings  form 
long  slender  tails,  so  that  the  Insects  scarcely  look  like  moths. 
They  are  peculiar  to  India  and  Africa.  In  the  South  African 
genus  Dianeura  (belonging  really  to  rhaudinae)  also  the  wings 
are  scaleless  and  nearly  transparent. 

Fam.  18.  Heterogynidae. — Consists  of  the  single  genus 
Hcterogynis  which  has  hitherto  been  found  only  in  the  south  of 
Europe.  This  is  an  important  form  connecting  Zygaenidae  and 
Psychidae.  The  larvae  resemble  those  of  Zygaena,  and  construct 
an  oval  cocoon  for  their  metamorphosis.  The  male  issues  as  a 
small  moth  of  smoky  colour,  the  scales  being  but  imperfect ; 
the  female  chrysalis  show's  no  trace  of  any  appendages,  and  the 
imago  is  practically  a  maggot,  and  never  leaves  the  cocoon  ;  in  it 
she  deposits  her  eggs,  and  the  young  larvae  hatch  there.1 

Fam.  19.  Psychidae. — Small,  or  moderate-sized  moths,  with 
imperfect  scales,  and  little  or  no  colour  beyond  certain  shades  of 
duskiness  ;  the  sexes  very  different,  the  female  being  wingless  and 
sometimes  quite  maggot-like ;  the  male  often  with  remarkable, 
bipectinate  antennae,  the  branches  sometimes  very  long  and 
flexible.  Larva  inhabiting  a  case  that  it  carries  about.  This 
family  consists  of  Insects  unattractive  in  appearance  but  present- 
ing some  points  of  great  interest.  It  is  frequently  stated  that 
the  Psychidae  are  destitute  of  scales,  but  Heylaerts  states'2  that, 
in  addition  to  hairs,  scales  of  a  more  or  less  imperfect  formation 
are  present  in  all,  but  that  they  are,  like  those  of  some  Sphingidae 
(Macroglossa),  very  easily  detached.  There  is  much  difference  in 
the  females,  some  having  well-developed  legs,  while  others  are 
not  only  apterous,  but  are  bare  and  destitute  of  appendages 
like  a  maggot,  while  in  certain  cases  (Fig.  196,  G),  the  head 
is  reduced  in  size  and  is  of  peculiar  form  so  as  to  make  the 
Insect  look  really  like  the  larva  of  one  of  the  parasitic  Diptera. 
These  females  never  leave  their  cases,  but  deposit  their  eggs 

1  For  details  as  to  habits,   etc.,   see  Ramlmr,   Ann.  Soc.  cut.  France,  v.  1836, 
p.  577  ;  and  Graslin,  <>p.  <•//.  xix.  1850,  p.  396. 

2  Monograph    of   European    T.sycliidae,    Ann.    Soc.    cut.    Bclyiqnc,    xxv.    1881, 
p.  29,  etc. 


VI 


HETEROCERA PSYCHIDAE 


393 


therein,  and  inside,  also,  their  former  pupa-skin  ;  and  here  the 
young  hatch  ;  the  peculiar  little  larvae  are  very  numerous,  and  it  is 
suggested  that  they  make  a  first  meal  on  the  body  of  their  parent, 
but  this  we  believe  has  not  been  satisfactorily  ascertained. 
Great  differences  as  to  the  condition  of  the  legs,  antennae,  etc., 
are  said  to  exist  in  species  of  the  same  genus.  There  is  also  a 
remarkable  diversity  in  the  pupae  of  the  females ;  the  male  sex 
being  normal  in  this  respect.  Some  of  the  female  pupae  are 
destitute  of  wing-sheaths  and  all  other  appendages,  while  others 
are  said  to  possess  them,  though  there  are  no  wings  at  all  in 
the  imago  (Fumea,  e.g.').1  Great  difficulties  attend  the  study  of 
these  case-bearing  Insects,  and  several  points  require  careful 


FIG.  196. — Metamorphosis  of  Monda  rhabdophora.  Ceylon.  A,  Larva  in  case,  nat. 
size  ;  B,  larva  itself,  magnified  ;  C,  case  of  female  during  pupation  ;  D,  case  of  male 
during  pupation  ;  E,  female  pupa,  magnified  ;  F,  male  moth,  nat.  size  ;  G,  female 
moth,  magnified.  ( From  unpublished  drawings  by  Mr.  E.  E.  Green). 

reconsideration,  amongst  them  the  one  we  have  just  mentioned. 
The  males  fly  rapidly  in  a  wild  manner,  and  may  sometimes 
be  met  with  in  swarms  ;  their  lives  are  believed  to  be  very  brief, 
rarely  exceeding  a  couple  of  days,  and  sometimes  being  limited 
to  a  few  hours. 

The  larvae  are  called  basket-worms,  and  their  baskets  or 
cases  are  wTell  worthy  of  attention.  Their  variety  is  remark- 
able ;  the  most  extraordinary  are  some  of  the  genus  Apterona 
Fig.  197,  B,  which  perfectly  resemble  the  shells  of  Molluscs 
such  as  snails ;  indeed,  the  specimens  in  the  collection  at 
the  British  Museum  were  sent  there  as  shells.  This  case  is  not, 
like  those  of  other  Psychidae,  constructed  of  earth  or  vegetable 
matter,  but  is  of  silk  and  is  in  texture  and  appearance  exactly 

1  Heylaerts,  op.  cit.  p.  55. 


394 


LEPIDOPTERA 


CHAP. 


like  the  surface  of  a  shell.  Psyche  helix  is,  according  to 
Ingenitzky,1  found  in  great  numbers  near  Lake  Issyk-kul  in 

Central  Asia,  where  the 
larvae  feed,  in  their  snail- 
shell-like  cases,  on  a  grass, 
just  like  snails.  Only 
females  could  be  reared 
from  these  larvae.  The 
case  of  Chalia  hockingii 
(Fig.  197,  C)  consists  of 
little  pieces  of  wood  cut 
to  the  proper  lengths,  and 
spirally  arranged,  so  as  to 
A  c  form  a  construction  that 

FIG.  197.  —  Baskets,   or   cases,    of  Psychidae.     A,    WOllld    be    quite   a  Credit  t»> 
Amictaquadrangularis;  B  Apterona(orCoch-  sneeies        Til   some 

lophora)  val-vata;  C,  Chalm  hockingi. 

of  the  Canephorinae  we 

meet  with  long  cylindrical  cases,  like  those  of  Caddis-worms,  or 
of  Tineid  larvae. 

lliley  has  given  an  account  of  several  points  in  the  struc- 
ture and  natural  history  of  one  of  the  North  American  basket- 
or  bag-  worms,  Thyridopteryx  ephemeraeformis  ;  one  of  his  points 
being  the  manner  in  which  the  newly  hatched  larva  forms  its 
case.'2  This  question  has  also  been  discussed  by  Packard.'1  The 
larvae  when  hatched  in  unnatural  conditions  will  make  use  of 
fragments  of  paper,  cork,  etc.,  for  the  case  ;  the  act  of  construc- 
tion takes  one  or  two  hours,  and  the  larva  does  not  eat  till  the 
case  is  completed.  It  walks  in  a  peculiar  manner,  the  legs  of 
the  third  pair  being  moved  forwards  together,  as  if  they  were 
the  prongs  of  a  fork. 

This  family  is  already  one  of  considerable  extent,  but  its 
study,  as  already  renmrked,  is  but  little  advanced.  Some 
naturalists  are  inclined  to  place  it  among  the  Tineidae,  but  it 
is  connected  with  Zygaenidae  by  means  of  Heterogynidae.  Mr. 
Meyrick  divides  it,  placing  Psyche  and  Sterrhopteryx  (the  forms 
representing,  according  to  his  ideas,  the  family  Psychidae  in 
Britain)  in  the  series  Psychina  which  includes  Zygaenidae.  He 


l.  An;,  xx.  1897,   p.  473.      This  is  probably  Aptcrona  crenulclla,  or  one 
of  its  varieties.  "  Hull.  U.S.  Dcp.  Aijric.  Ent.  x.  1S37,  p.  22. 

3  Ann.  New  ]"«>•/•  ./-•.  viii.  IS'i:',,  p.  54. 


vi  HETEROCERA PSYCHIDAE- — COSSIDAE  395 

removes  the  other  British  genera,  Fumea  and  Epichnopteryx,  to 
Tineidae  near  Solenobia  and  Taleporia.  The  group  Canephorinae, 
to  which  the  two  genera  in  question  belong,  was  long  since  separ- 
ated from  Psychidae  by  Herrich-Schaffer,  but  this  course  was 
condemned  by  Heylaerts.  Parthenogenesis  has  been  thought  by 
some  to  occur  in  numerous  species  in  this  family,  but  Heylaerts 
says  that  it  is  limited  to  Apterona  crenulella  var.  helix,  and  even 
of  this  species  males  are  found  in  certain  localities. 

Fam.  20.  Cossidae  (Goat -Moths,  or  Carpenter -Worms}.— 
Moths  of  moderate,  or  rather  large  size,  without  proboscis,  fre- 
quently with  a  dense  covering  of  matted,  imperfect  scales ;  the 
pattern  being  vague.  The  larvae  bore  into  trees  in  which  they 
often  make  large  burrows,  leaving  holes  from  which  sap  exudes. 
Our  common  Goat-moth  is  a  good  specimen  of  this  family,  which 
is  a  very  widely  distributed  one.  The  Australian  genus  Ptilo- 
macra  has  very  large,  pectinated  antennae  in  the  male.  The 
larvae  of  Cossidae  are  nearly  bare  of  clothing  and  are  unadorned  ; 
they  form  a  slight  cocoon  of  silk  mixed  with  gnawed  wood. 
The  pupa  of  the  Goat-moth  is  remarkable  for  the  great  develop- 
ment of  the  rows  of  teeth  on  the  dorsal  aspects  of  the  segments 
of  the  abdomen,  and  for  the  absence  of  consolidation  in  this 
part,  six  of  the  intersegmental  incisions  being  free,  and  the 
ventral  aspect  almost  membranous.  Very  little  is  known  as  to 
other  pupae  of  the  family.  It  is  believed  that  the  generations 
of  these  Insects  are  fewer  than  usual,  the  growth  of  the  larva 
occupying  a  period  of  two  or  three  years.  The  larva  of  Zeuzera 
aesculi  forms  a  temporary  cocoon  in  which  it  passes  a  winter- 
sleep,  before  again  feeding  in  the  spring.1  It  is  a  moot  question 
whether  the  Zeuzeridae  should  be  separated  from  the  Cossidae  or 
not.  The  group  includes  our  Wood-leopard  moth,  which,  like 
many  other  Zeuzerids,  is  spotted  in  a  very  striking  but  inartistic 
manner.  The  position  the  family  Cossidae  should  occupy  in  an 
arrangement  of  the  Lepidoptera  is  a  very  difficult  question.  Some 
consider  the  Insects  to  be  allied  to  Tortricidae.  The  wing-nervura- 
tion  of  Cossus  is  very  peculiar  and  complex,  there  being  four  or 
five  cells  on  the  front  wing,  and  three  on  the  hind  one.  Meyrick 
places  Zeuzeridae  as  a  family  of  his  series  Psychina,  but  separ- 
ates Cossidae  proper  (he  calls  them  Trypauidae)  as  a  family  of 
the  series  Tortricina. 

1  Kalender,  Ent.  Zcit.  Stettin,  xxxv.  1874,  p.  203. 


396  LEPIDOPTERA  CHAP. 

Fam.  21.  Arbelidae. — Closely  allied  to  Cossidae,  but  with- 
out frenulum,  and  with  less  complex  wing-nervures.  A  small 
family  believed  to  be  similar  to  Cossidae  in  the  life-history. 
The  tropical  African  Arbelidae  are  considered  by  Karsch  to  be 
a  distinct  family,  Hollandiidae. 

Fam.  22.  Chrysopolomidae. — This  family  has  been  estab- 
lished by  Dr.  Aurivillius  l  for  an  African  genus,  allied  in  wing- 
nervuration  to  Cossidae ;  the  Insects  are  like  Lasiocampidae. 

Fam.  23.  Hepialidae  (Ghost-  and  Svrift-Moths). — Moths  of 
very  diverse  size,  some  gigantic ;  wings  not  fitting  together  well 
at  the  bases ;  without  a  frenulum ;  no  proboscis ;  the  scales 
imperfect ;  the  nervures  complex.  The  Hepialidae  are  extremely 
isolated  amongst  the  Lepidoptera  ;  indeed,  they  have  really  no 
allies ;  the  conclusion  that  they  are  connected  with  the  Micro- 
pti'rygidae  being  certainly  erroneous.  Although  but  small  in 
numbers — only  about  150  species  being  known — they  exhibit  a 
remarkable  variety  in  size  and  colour.  Many  are  small  obscure 
moths,  while  others  are  of  gigantic  size — six  or  seven  inches 
across  the  wings — and  are  amongst  the  most  remarkably  coloured 
of  existing  Insects.  The  great  Charagia  of  Australia,  with 
colours  of  green  and  rose,  bearing  white  spots,  are  remarkable. 
The  South  African  Leto  venus  is  of  large  size,  and  has  an 
astonishing  supply  of  glittering  metallic  splashes  on  the  wings, 
making  a  barbaric  but  effective  display.  The  South  Australian 
Zelotypia  staceyi,  of  enormous  size,  is  also  a  handsome  ninth: 
but  the  majority  of  species  of  the  family  are  adorned  only  in 
the  feeblest  manner. 

Very  little  is  known  as  to  the  larvae  ;  they  are  either  sub- 
terranean, feeding  on  roots,  or  they  live  in  the  wood  of  trees  and 
shrubs.  They  are  nearly  bare,  and  are  apparently  the  lowest  type 
of  Bombycid  larva.  At  the  same  time,  it  would  appear  there  is 
considerable  variety  amongst  them.  Packard  says 2  the  young 
larva  of  Jfi-ju'/tfi/s  mustelines  has  the  arrangement  of  setae  that  is 
normal  in  Tineidae.  The  larva  of  H.  hurnali  seems  to  be  a  very 
simple  form,  but  H.  liectus  shows  a  considerable  amount  of 
divergence  from  it.  They  probably  live  for  several  years;  the 
larva  of  //.  (irgenteo-iii<«-nl<it  us  in  North  America  lives  for  three 
years,  ;it  first  eating  the  roots  of  Alder  and  then  entering  the 

1   Ent.  Ti-dsTcr.  xvi.  isnr,.  ),.  n r>. 

-  On  lurvnr  (.]'  Hrjiialidau,  J.  JW«:  York  c nf.  Soc.  iii.  1895,  p.  69,  Plates  III.  IV. 


VI 


HETEROCERA HEPIALIDAE 


397 


stems.  The  pupae  are  also  peculiar.  They  are  of  unusually 
elongate,  cylindrical  form,  with  comparatively  feeble  integument, 
Luc  with  a  considerable  development  of  chitinous,  elevated,  toothed 
ridges,  on  the  dorsal  aspect,  and  a  very  strong  ridge  of  this  kind 
on  the  ventral  surface  of 
the  seventh  segment ;  the 
wing-sheaths  are  short;  it 
is  very  difficult  to  distinguish 
the  full  number  of  abdominal 
segments.  These  pupae  are 
remarkably  agile,  and  by 
wriggling  and  kicking  are 
able  to  move  a  considerable 
distance  ;  it  is  said  that  they 
can  force  themselves  to  the 
surface  even  when  the  super- 
ficial soil  is  quite  hard. 
We  cannot  consider  this 
pupa  naturally  placed 
either  the  pupae 


amongst 


x-O 


Britain. 


obtectae    or    incompletae    of  FIG- 198.— ?\\y&ofHepiaiuship'uiini<s. 

A,  Ventral  ;  B,  dorsal  aspect. 

Chapman. 

We  have  already  remarked  that  little  is  known  as  to  the 
life-histories.  The  species  are  probably  prolific,  a  female  of 
H.  thule  having  been  known  to  deposit  more  than  2000  eggs. 
Of  the  Australian  forms  little  more  is  known  :  than  that  they  live 
in  the  wood  of  trees  and  shrubs,  and  are  rapidly  disappearing  ; 
we  may  fear  that  some  are  extinct  without  ever  having  been 
discovered,  and  others,  also  unknown  but  still  existing,  may 
disappear  only  too  soon  ;  the  wasteful  destruction  of  timber  in 
Australia  having  been  deplorable. 

The  peculiar  habits  of  the  Hepialidae  are  not  likely  to  bring 
the  Insects  to  the  net  of  the  ordinary  collector,  and  we  believe 
they  never  fly  to  light,  hence  it  is  probable  that  we  are 
acquainted  with  only  a  small  portion  of  the  existing  species ; 
their  distribution  is  very  wide,  but  Australia  seems  to  be  their 
metropolis,  and  in  Xew  Zealand  twelve  species  are  known.  The 
genera  as  at  present  accepted  are  remarkable  for  their  wide 
distribution.  Leto  is  said  to  occur  in  South  Africa  and  in  the 

1  Olliff,  Australian  Hepialidae,  Ento-i>K>!o<jist,  xxviii.  1895,  p.  11-L 


398  LEPIDOPTERA  CHAP. 

Fiji  Islands  ;  but  we  must  repeat  that  the  study  of  these 
interesting  Insects  is  in  a  very  primitive  state,  and  our  present 
knowledge  of  their  distribution  may  be  somewhat  misleading. 

The  habits  of  the  European  Hepialus  in  courtship  have  been 
observed  to  a  considerable  extent  and  are  of  great  interest,  an 
astonishing  variety  and  a  profound  distinction  in  the  methods 
by  which  the  sexes  are  brought  together  having  been  revealed. 

H.  humuli,  our  Ghost-moth,  is  the  most  peculiar.  Its 
habits  were  detected  by  Dr.  Chapman.1  The  male  is  an 
Insect  of  exceptional  colour,  being  white  above,  in  consequence  of 
a  dense  formation  of  imperfect  scales  ;  the  female  is  of  the 
brownish  tints  usual  in  Swift  -moths.  In  the  month  of  June 
the  male  selects  a  spot  where  he  is  conspicuous,  and  hovers 
persistently  there  for  a  period  of  about  twenty  minutes  in  the 
twilight  ;  his  colour  has  a  silvery-  white,  glistening  appearance, 
so  that  the  Insect  is  really  conspicuous  notwithstanding  the 
advanced  hour.  Females  may  be  detected  hovering  in  a  some- 
what similar  manner,  but  are  not  conspicuous  like  the  male, 
their  colour  being  obscure;  while  so  hovering  they  are  oviposit- 
ing, dropping  the  eggs  amongst  the  grass.  Females  that  have 
not  been  fertilised  move  very  differently  and  dash  about  in 
an  erratic  manner  till  they  see  a  male  ;  they  apparently  have 
no  better  means  of  informing  the  hovering  male  of  their  presence 
than  by  buzzing  near,  or  colliding  with  him.  Immediately  this 
is  done,  the  male  abandons  his  hovering,  and  coupling  occurs. 
There  can  be  little  doubt  that  the  colour  of  the  male  attracts 
the  female;  but  there  is  a  variety,  hethlandica,  of  the  former 
sex  coloured  much  like  the  female,  and  in  some  localities 
varieties  of  this  sort  are  very  prevalent,  though  in  others  the 
species  is  quite  constant.  This  variation  in  the  colour  of  the 
males  is  very  great  in  Shetland,2  some  being  quite  like  the 
females.  In  H.  kcctus  the  two  sexes  are  inconspicuously  and 
similarly  coloured.  The  male  hovers  in  the  afternoon  or  evening 
in  a  protected  spot,  and  while  doing  so  diffuses  an  agreeable 
odour  —  said  by  Barrett  to  be  like  pine-apple  —  and  this  brings 
the  female  to  him,  much  in  the  same  manner  as  the  colour 
of  If.  li  a  in  nil  brings  its  female.  The  hind  legs  of  the  male 


1  Ent.  Minj.  xiii.  1876,  p.  63  ;  ami  xxiii.  1886,  p.  164. 

'  Weir,  J'Jii/ini/ii/iii/is/,  xiii.   1S80,   p.   219,   plate  ;    King,  Ent.  llcconl,  vii.  1895, 
p.  111. 


vr  IIETEROCERA- — HEPIALIDAE  399 

are  swollen,  being  filled  with  glands  for  secreting  the 
odorous  matter.1  This  structure  has  led  to  the  suggestion  of 
the  generic  name  Phymatopus  for  the  Insect.  Turning  to 
other  species  of  the  genus,  we  find  that  the  normal  rela- 
tive roles  of  the  sexes  are  exhibited,,  but  with  considerable 
diversity  in  the  species.  In  H.  lupulinus  the  males  fly  about 
with  rapidity,  while  the  female  sits  on  a  stem  and  vibrates 
her  wings ;  she  thus  attracts  the  males,  but  they  do  not 
perceive  her  unless  happening  to  come  within  three  or  four 
feet,  when  they  become  aware  of  her  proximity,  search  for  and 
find  her.  It  is  doubtful  whether  the  attraction  is  in  this  case 
the  result  of  an  odour ;  it  would  appear  more  probable  that  it 
may  be  sound,  or  that  the  vibration  of  the  wings  may  be  felt  by 
the  male. 

In  H.  sylmnus,  H.  velleda  and  H.  pyrenaicus  less  abnormal 
modes  of  attracting  the  males  occur,  the  individuals  of  this  latter 
sex  assembling  in  great  numbers  at  a  spot  where  there  is  a  female. 
In  the  first  of  the  three  species  mentioned  the  female  sits  in  the 
twilight  on  the  stem  of  some  plant  and  vibrates  the  wings  with 
rapidity ;  she  does  not  fly ;  indeed,  according  to  Mr.  Eobson,  she. 
does  not  till  after  fertilisation  move  from  the  spot  where  she 
emerged.  In  H.  pyrenaicus  the  female  is  quite  apterous,  but  is 
very  attractive  to  the  males,  which  as  we  have  said,  assemble 
in  large  numbers  near  her.  Thus  within  the  limits  of  these 
few  allied  forms  we  find  radically  different  relations  of  the 
sexes. 

1.  The  male  attracts  the  female— (A)  by  sight  (H.  humuli) ; 

(B)  by  odour  (H.  liectus}. 

2.  The  female  attracts  the  male — (A)  by  vibration  of  wings 

(H.  lupulinus  and  If.  sylvinus) ;  (B)  without  vibration, 
but  by  some  means  acting  at  a  distance  (H.  velleda, 
If.  pyrenaicus}. 

Little  or  nothing  is  known  as  to  the  habits  of  the  great 
majority  of  the  more  remarkable  forms  of  the  family.  The 
gigantic  Australian  forms  are  believed  to  be  scarcely  ever  seen  on 
the  wing. 

The  Hepialidae  differ  from  other  Lepidoptera  by  very  im- 
portant anatomical  characters.  The  absence  of  most  of  the 

1  Bertkau,    S£.    Vcr.    Rheinland,    xxxvi.    1879,    p.    288  ;    and  Arch.    Natury. 
xlviii.  i.  1882,  p.  362. 


400  LEPIDOPTERA  CHAP. 


mouth-parts  is  a  character  common  to  them  and  several  other 
divisions  of  Lepidoptera ;  but  the  labial  palpi  are  peculiarly 
formed  in  this  family,  being  short  and  the  greater  portion  of 
their  length  consisting  of  an  undivided  base,  which  probably 
represents  some  part  of  the  labiuin  that  is  membranous  in 
normal  Lepidoptera.  The  thoracic  segments  are  remarkably 
simple,  the  three  differing  less  from  one  another  than  usual,  and 
both  meso-  and  nieta-notum  being  much  less  infolded  aud  co- 
ordinated. The  wings  are  remarkable  for  the  similarity  .of  the 
ncrvuration  of  the  front  and  hind  wings,  and  by  the  cell  being- 
divided  by  longitudinal  nervules  so  as  to  form  three  or  four 
cells.  On  the  inner  margin  of  the  front  wing  there  is  near 
the  base  an  incision  marking  off  a  small  prominent  lobe,  the 
jugmii  of  Prof.  Comstock.  Brandt  mentions  the  following 
anatomical  peculiarities,1  viz.  the  anterior  part  of  the  alimentary 
canal  is  comparatively  simple ;  the  respiratory  system  is  in  some 
points  like  that  of  the  larva  ;  the  heart  is  composed  of  eight 
chambers ;  the  appendicular  glands  of  the  female  genitalia  are 
wanting.  The  testes  remain  separate  organs  throughout  life. 
The  chain  of  nerve  ganglia  consists  of  the  supra-  and  iufra- 
oesophageal,  three  thoracic,  and  five  abdominal,  ganglia,  while 
other  Lepidoptera  have  four  abdominal. 

Fam.  24.  Callidulidae. — -A  small  family  of  light  -  bodied 
diurnal  moths  having  a  great  resemblance  to  butterflies.  In 
some  the  frenulum  is  present  in  a  very  rudimentary  condition, 
and  in  others  it  is  apparently  absent.  Cleosiris  and  J'f<rodecta  are 
very  like  butterflies  of  the  Lycaenid  genus  Thccln.  Although 
fifty  species  and  seven  or  eight  genera  are  known,  we  are  quite 
ignorant  of  the  metamorphoses.  Most  of  the  species  are  found 
in  the  islands  of  the  Malay  Archipelago,  but  there  are  a  few  in 
East  India. 

Fam.  25.  Drepanidae  (or  Drepanulidae).  (Hook-tips}. — The 
larger  moths  of  this  family  are  (A  moderate  size ;  many  of 
the  species  have  the  apex  of  the  front  wing  pointed  or  even 
hooked ;  some  have  very  much  the  appearance  of  Geometrid 
moths;  they  resemble  very  different  members  of  that  family. 
(h-i'hi.  liyalodisca  is  remarkable  on  account  of  the  very  large, 
transparent  patch  on  each  front  wing,  though  the  other  species 
of  the  genus  have  nothing  of  the  sort.  In  the  genus  Deroca  we 

1  Zoo!.  An;,  iii.  is.SD,  p.  18(5. 


VI 


HETEROCERA DREPANIDAE LIMACODIDAE 


4OI 


find  Insects  with  the  scales  imperfect,  they  being  few  and  small 
and  approximating  in  form  to  hairs  ;  in  D.  hyalina  scales  are 
nearly  entirely  absent.  In  other  genera,  e.g.  Peridrepana,  Stre^>- 
toperas,  there  is  only  a  very  inferior  state  of  scale -formation. 
The  few  larvae  that  are  known  are  peculiar ;  they  are  nearly 
bare  of  hair,  without  the  pair  of  terminal  claspers,  while  the 
body  is  terminated  by  a  long  tubular  process.  They  form  a 
slight  cocoon  among  leaves. 

The  members  of  the  family  were  formerly  much  misunder- 
stood, and  were  assigned  to  various  positions  in  the  Order. 
There  are  now  about  30  genera,  and  150  species  known,  the 
geographical  distribution  of  the  family  being  very  wide.  In 
Britain  we  have  half  a  dozen  species.  Cilix  glaucata  (better 
known  as  G.  spinula)  is  said  "  to  undoubtedly  imitate "  the 
excrement  of  birds.  No  doubt  the  Insect  resembles  that  sub- 
stance so  as  to  be  readily  mistaken  for  it.  This  Insect  has  a 
very  wide  distribution  in  North  America,  Europe  and  East 
India,  and  is  said  to  vary  so  much  in  the  structure  of  its  organs 
as  to  justify  us  in  saying  that  the  one  species  belongs  to  two  or 
three  genera. 

Fam.  26.  Limacodidae  (or  Eucleidae). — These  are  some- 
what small  moths,  of  stout  formation,  sometimes  very  short  in 
the  body,  and  with  rather  small  wing  -  area.  The  family 
includes  however  at  present  many  Insects  of  diverse  appearance  ; 
there  are  numerous  forms  in  which 
apple-green  is  a  prominent  colour  : 
some  bear  a  certain  resemblance 
to  the  Swifts,  others  to  Noctuids  ; 
som.e,Hosema  and  Staetkerinia,are  of 
extraordinary  shapes  ;  certain  very 
small  forms,  Gavara,  Ceratonema, 
resemble  Tortricids  or  Tineids ;  a 
few  even  remind  one  of  Insects  of  FlG-  199.— Mature  larva  of  Apoda 

testudo,  on  beech-leaf.     Britain. 

other  Orders ;  so  that  the  group  is 

a  mimetic  one.  Nagoda  nigricans  (Ceylon)  has  the  male  some- 
what like  a  Psychid,  while  the  female  has  a  different  system  of 
coloration  and  wing-form.  In  Scopelodes  the  palpi  are  in  both 
sexes  remarkable  ;  elongated,  stiff,  directed  upwards  and  brush- 
like  at  the  tip.  Altogether  there  are  about  100  genera  and 
400  species  known  ;  the  distribution  of  the  family  is  very  wide 
VOL.  vi  2  D 


402 


LEPIDOPTERA 


CHAP. 


iu  both  hemispheres,  but  these  Insects  do  not  occur  in  insular 
faunas.  In  Britain  we  have  two  genera,  Hcterogenea  and  Apoda 
(better  known  as  Limacodes x),  each  with  a  single  species. 

The  early  stages  of  these  Insects  are  of  great  interest.  The 
eggs,  so  far  as  known,  are  peculiar  fiat  oval  scales,  of  irregular 
outline  and  transparent ;  we  have  figured  an  example  in  Vol.  V. 
Fig.  83.  The  eggs  of  the  same  moth  are  said  to  vary  much 
in  size,  though  the  larvae  that  emerge  from  them  differ  little 

from  one  another  in  this  respect.  The 
latter  are  peculiar,  inasmuch  as  they 
have  no  abdominal  feet,  and  the 
thoracic  legs  are  but  small ;  hence  the 
caterpillars  move  in  an  imperceptible 
gliding  manner  that  has  suggested  for 
some  of  them  the  name  of  slug-worms. 
The  metamorphoses  of  a  few  are 
known.  They  may  be 


A  V—- 


arranged    in 

two  groups ;  one  in  which  the  larva 
is  spinose  or  armed  with  a  series  of 
projections  and  appendages  persisting 
throughout  life  ;  while  in  the  members 
of  the  second  group  the  spines  have 
only  a  temporary  existence.  At  the 
moment  the  young  larva  of  Apoda 
testudo  emerges  from  the  egg  it 

FIG.  200.—  Larva  of  Ajx>d<(  tcxtndo    ]lag  nQ  COnspicuOUS  SpillCS  01'  processes, 
just  hatched.      A,  Dorsal  view 

of  larva  ;  B,  C,  D,  a  spine  in  and    is  an    extremely    soft,   colourless 
different  states  of  evagination     creature 2    but    it    almost    immediately 

All  magnified.  (After  Chapman.) 

displays  a  remarkable  system  of  com- 
plex spines.  These  really  exist  in  the  larva  when  it  is 
hatched,  and  are  thrust  out  from  pits,  as  explained  by 
Dr.  Chapman.  In  the  succeeding  stages,  the  spines  become 
modified  in  form,  and  the  colour  of  the  body  and  the  nature  of 

1  It  is  much  to  be,  regretted  that,  as  in  so  many  other  Lepidoptera,  no  satis- 
factory agreement  as  to   names   has    been  attained';  -our   British  A.   tcstudo   is 
variously  styled   Limacodes  testudo  (by  Chapman  and  most  naturalists),  Apoda 
liiiiKi-oifcn' C\<y  Meyrick),  or  Apoda  ai'cllana  (Kirby,    Catalogue  of  Motlis}.      The 
family  is  called  either  Limacodidae,  Apodidae,  Cochliopodidae,  or  Heterogeneidae. 

2  See  Chapman,  Tr.  ait.  Soc.  London,  1894,  p.  345,  Plate  VII.,  for  our  British 
species  ;  for  North  American  forms,  Dyar,  Life-histories  of  the  New  York  Sluy-cater- 
pillars  (in  progress,  with  numerous  plates),  J.  Neiv  York  cut.  Soc.  iii.  etc.,  1895. 


vi  HETEROCERA  —  LIMACODIDAE  403 

the  integument  are  much  changed,  so  that  in  the  adult 
larva  (Fig.  199)  the  spines  have  subsided  into  the  condition 
of  mere  prominences,  different  in  colour  from  the  rest  of 
the  surface.  These  larvae  appear  to  be  destitute  of  a  head, 
hut  there  really  exists  a  large  one  which  is  retracted,  except 
during  feeding,  into  the  body ;  the  five  pairs  of  abdominal  feet  of 
the  larvae  of  allied  families  are  replaced  by  sucker-like  structures 
on  the  first  eight  abdominal  segments.  The  spinneret  of  the 
mouth  is  not  a  pointed  tubular  organ,  but  is  fish-tailed  in  shape, 
and  hence  disposes  the  silky  matter,  that  aids  the  larva  in  mov- 
ing on  the  leaves,  in  the  form  of  a  ribbon  instead  of  that  of  a 
thread.  It  has  been  stated  that  these  peculiar  larvae  "  imitate  " 
the  coloured  galls  frequently  found  on  the  leaves  of  trees.  The 
North  American  forms  of  this  family  have  very  varied  and  most 
extraordinary  larvae.1  In  the  pretty  and  conspicuous  larva  of 
Empretia  stimulea,  the  tubercles  or  processes  of  the  body  are,  in 
the  later  stages,  armed  with  hairs,  that  contain  a  poisonous  or 
irritating  fluid,  said  to  be  secreted  by  glands  at  the  bases  of  the 
processes.  These  hairs  are  readily  detached  and  enter  the  skin 
of  persons  handling  the  caterpillars.  The  larva  of  the  North 
American  Hag-moth,  Phobetron  pithecium,  is  a  curious  object, 
bearing  long,  fleshy  appendages  covered  with  down.  Hubbard 
makes  the  following  statement  as  to  the  instincts  of  this  larva  : 2- 
'  The  hag-moth  larvae  do  not  seek  to  hide  away  their  cocoons, 
but  attach  them  to  leaves  and  twigs  fully  exposed  to  view,  with, 
however,  such  artful  management  as  to  surroundings  and  har- 
monising colours  that  they  are  of  all  the  group  the  most  difficult 
to  discover.  A  device  to  which  this  Insect  frequently  resorts 
exhibits  the  extreme  of  instinctive  sagacity.  If  the  caterpillar 
cannot  find  at  hand  a  suitable  place  in  which  to  weave  its 
cocoon,  it  frequently  makes  for  itself  more  satisfactory  surround- 
ings by  killing  the  leaves,  upon  which,  after  they  have  become 
dry  and  brown  in  colour,  it  places  its  cocoon.  Several  of  these 
caterpillars  unite  together,  and  selecting  a  long  and  vigorous 
immature  shoot  or  leader  of  the  orange  tree,  they  kill  it  by 
cutting  into  its  base  until  it  wilts  and  bends  over.  The 
leaves  of  a  voung  shoot  in  drying  turn  a  light  tan-color,  which 

*/  O  v  O  O 


1  See  Packard,  P.  Amcr.  Phil.  Sue.  xxxi.  1893,  pp.  83,  108,  Plates.     (He  uses 
the  term  Cochliopodidae  instead  of  Limacodidae)  ;  also  Dyar,  as  above. 
-  Insects  affectiny  the  Oranyc,  "Washington,  1885,  p.  143. 


404  LEPIDOPTERA  CHAP. 

harmonises  most  perfectly  with  the  hairy  locks  of  the  caterpillar 
covering  the  cocoon.  The  latter  is,  consequently,  not  easily 
detected,  even  when  placed  upon  the  exposed  and  upturned 
surface  of  the  leaf." 

The  cocoons  of  Limacodidae  are  unusually  elaborate,  the 
larva  forming  a  perfect  lid  in  order  to  permit  itself  to  escape 
when  a  moth.  Chapman  states  that  the  larva  lies  unchanged 
in  the  cocoon,  all  winter,  moulting  to  a  pupa  in  the  spring,  and 
that  the  pupa  escapes  from  the  cocoon  previous  to  the  emergence 
of  the  moth.1  Both  Chapman  and  Packard  look  on  the  family 
as  really  nearer  to  Microlepidoptera  than  to  Bombyces ;  Meyrick 
(calling  it  Heterogeneidae)  places  it  at  the  end  of  his  series 
Psychina  next  Zygaenidae. 

We  may  allude  here  to  the  little  moths,  described  by  West- 
wood  under  the  name  of  Epipyrops?  that  have  the  extraordinary 
habit  of  living  on  the  bodies  of  live  Homopterous  Insects  of  the 
family  Fulgoridae  in  India.  What  their  nutriment  may  be  is 
not  known.  The  larva  exudes  a  white  flocculent  matter,  which 
becomes  a  considerable  mass,  in  the  midst  of  which  the  caterpillar 
changes  to  a  pupa.  Westwood  placed  the  Insect  in  Arctiidae  ; 
Sir  George  Hampson  suggests  it  may  be  a  Limacodid,  and  this 
appears  prol  table. 

Fam.  27.  Megalopygidae  (or  Lagoidae). — The  American 
genera,  Megalopyge  and  Lagoa,  are  treated  by  Berg  and  by 
Packard3  as  a  distinct  family  intermediate  between  Saturniidae 
and  Limacodidae.  The  larva  is  said  by  the  latter  authority  to 
have  seven  pairs  of  abdominal  feet  instead  of  live  pairs — the 
usual  number  in  Lepidoptera,  When  young  the  caterpillars  of 
Lagoa  o]>?irnl<iris  are  white  and  resemble  a  Mock  of  cotton  wool. 
When  full  grown  the  larva  presents  the  singular  appearance  of 
a  lock  of  hair,  moving  in  a  gliding,  slug-like  manner.  Under 
the  long  silky  hair  there  are  short,  stiff,  poison  -  hairs.  The 
larva  forms  a  cocoon,  fitted  with  a  hinged  trap-door  for  the 
escape  of  the  future  moth.  This  curious  larva  is  destroyed  by 
both  Dipterous  and  Hymenopterous  parasites. 

Fam.  28.  Thyrididae. — A  small  family  of  Pyraloid  moths, 
exhibiting  considerable  variety  of  form  and  colour,  frequently 
with  hyaline  patches  on  the  wings.  They  are  mostly  small 

1    Tr.  cut.  Sue.  Lv,ul»ii.  1894,  p.  348.         '2  Op.  cif.  1876.  p.  522  ;  and  1S77,  p.  433. 
3  P.  Amer.  Phil.  Soc.  xxxii.  1894,  p.  27u. 


vi  HETEROCERA THYRIDIDAE LASIOCAMPIDAE          405 

Insects,  and  contain  no  very  striking  forms.  Some  of  them 
look  like  Geometrids  of  various  groups.  The  family  is  widely 
distributed  in  the  tropical  zone,  and  includes  25  genera,  of 
which  lihodoneura,  with  upwards  of  100  species,  is  the  chief 
one.  The  larvae  are  said  to  be  similar  to  those  of  Pyralidae. 
This  family  is  considered  by  Hampson  and  Meyrick  to  be 
ancestral  to  butterflies.1 

Fam.  29.  Lasiocampidae  (Eyycrs,  Lappet -moths'). — Usually 
large  Insects  densely  covered  with  scales,  without  frenulum, 
but  with  the  costal  area  of  the  hind  wing  largely  developed, 
and  the  male  antennae  beautifully  pectinate,  Lasiocampids  are 
easily  recognised.  They  are  well  known  in  Britain,  though  we 
have  but  few  species.  The  flight  of  some  of  the  species  is 
powerful,  but  ill-directed,  and  the  males  especially,  dash  about 
as  if  their  flight  were  quite 
undirected  ;  as  indeed  it 
probably  is.  The  differ- 
ence in  the  flight  of  the 
two  sexes  is  great  in  some 
species.  In  the  genus 
Suana  and  its  allies  we  meet 
with  moths  in  which  the 
difference  in  size  of  the  FIG.  201. — Lappet-moth,  Gastropacha  querci- 

two  sexes  is  extreme ;  the  llia>  ?'    BritahK 

males  may  be  but  1^-  inches  across  the  wings,  while  the  very 
heavy  females  may  have  three  times  as  great  an  expanse.  Kirby 
separates  these  Insects  to  form  the  family  Pinaridae ;  it  in- 
cludes the  Madagascar  silkworm,  Boroccra  madagascariensis. 
The  African  genus  Hilbrides  is  remarkable  for  the  wings  being 
destitute  of  scales,  and  consequently  transparent,  and  for  being  of 
very  slender  form  like  a  butterfly.  The  eggs  of  Lasiocampidae 
are  smooth,  in  certain  cases  spotted  in  an  irregular  manner  like 
birds'  eggs.  Sometimes  the  parent  covers  them  with  hair. 
The  larvae  are  clothed  with  a  soft,  woolly  hair,  as  well  as  with  a 
shorter  and  stiffer  kind,  neither  beautifully  arranged  nor  highly 
coloured,  and  thus  differing  from  the .  caterpillars  of  Lyman- 
triidae ;  this  hair  in  some  cases  has  very  irritating  pro- 
perties. Cocoons  of  a  close  and  compact  nature  are  formed,  and 
hairs  from  the  body  are  frequently  mixed  with  the  cocoon.  In 
1  Revision  of  the  Thyrididae  ;  Hampson,  P.  Zool.  Soc.  London,  1897,  p.  603. 


406  LEPIDOPTERA 


CHAT. 


some  species  the  walls  of  the  cocoons  have  a  firm  appear- 
ance, looking  very  like  egg-shell — a  fact  which  is  supposed  to 
have  given  rise  to  the  name  of  Eggers.  Professors  Poulton 
and  Meldola  have  informed  us  that  this  appearance  is  produced 
by  spreading  calcium  oxalate  on  a  slight  framework  of  silk, 
the  substance  in  question  being  a  product  of  the  Malpighian 
tubes.1  In  various  families  of  Lepidoptera  it  happens  that 
occasionally  the  pupa  exists  longer  than  usual  before  the  appear- 
ance of  the  perfect  Insect,  and  in  certain  members  of  this  family 
—notoriously  in  Poecilocampa  populi,  the  December  moth — this 
interval  may  lie  prolonged  for  several  years.  There  is  not  at 
present  any  explanation  of  this  fact.  It  may  lie  of  interest  to 
mention  the  following  case  : — From  a  batch  of  about  100  eggs 
deposited  by  one  moth,  in  the  year  1891  (the  Puss-Moth  of  the 
family  Notodontidae),  some  sixty  or  seventy  cocoons  were  obtained, 
the  feeding  up  of  all  the  larvae  having  been  effected  within 
fourteen  days  of  one  another ;  fourteen  of  the  Insects  emerged 
as  moths  in  1892  ;  about  the  same  number  in  1893  ;  in  1894, 
twenty-five;  and  in  1895,  eleven  emerged.  Lasiocampidae  is  a 
large  family,  consisting  of  some  100  genera  and  500  or  more 
species,  and  is  widely  distributed.  It  is  unfortunately  styled 
Bombycidae  by  some  naturalists. 

Fam.  30.  Endromidae.  -  -The  "Kentish  glory,"  Enclromis 
versicolo)-,  forms  this  family ;  it  is  a  large  and  strong  moth,  and 
flies  wildlv  in  the  daytime  in  birch-woods.  The  larva  has  but 

U  I/ 

few  hairs,  and  is  said  when  young  to  assume  a  peculiar  position, 
similar  to  that  of  saw-fly  larvae,  by  bending  the  head  and  thorax 
backwards  over  the  rest  of  the  body. 

Fam.  31.  Pterothysanidae. — Consists  of  the  curious  East 
Indian  genus  Pterothysanus,  in  which  the  inner  margins  of  the 
hind  wings  are  fringed  with  long  hairs.  They  are  moths  of 
slender  build,  with  large  wing-expanse,  black  and  white  in  colour, 
like  Geometrids.  There  is  no  frenulum.  Metamorphoses  un- 
known. 

Fam.  32.  Lymantriidae. — (Better  known  as  Liparidae\ 
These  are  mostly  small  or  moderate-sized  moths,  without  brilliant 
colours ;  white,  black,  grey  and  brown  being  predominant :  with 
highly-developed,  pectinated  antennae  in  the  male.  The  larva 
is  very  hairy,  and  usually  bears  tufts  or  brushes  of  shorter  hairs, 

1  P.  cnt.  Soc.  London,  1891,  p.  xv. 


vi  HETEROCERA — LYMANTRIIDAE  407 

together  with  others  much  longer  and  softer,  these  being  some- 
times also  amalgamated  to  form  pencils ;  the  coloration  of  these 
larvae  is  in  many  cases  very  conspicuous,  the  tufts  and  pencils 
being  of  vivid  and  strongly  contrasted  colours.  Some  of  these 
hairy  larvae  are  poisonous.  A  cocoon,  in  which  much  hair  is 
mixed,  is  formed.  The  pupae  are  remarkable,  inasmuch  as  they 
too  are  frequently  hairy,  a  very  unusual  condition  in  Lepidoptera. 
The  Lyrnantriidae  is  one  of  the  largest  families  of  the  old  group 
Bombyces;  it  includes  some  180  genera  and  800  species,  and  is 
largely  represented  in  Australia.  Dasyehira  rossii  is  found  in  the 
Arctic  regions.  In  Britain  we  have  eight  genera  represented  by 
eleven  species ;  the  Gold-tails,  Brown-tails  and  Vapourer-moths 
being  our  commonest  Bombyces,  and  the  latter  being  specially  fond 
of  the  London  squares  and  gardens,  where  its  beautiful  larva  may 
be  observed  on  the  leaves  of  roses.  Most  of  the  Lymantriidae  are 
nocturnal,  but  the  male  Vapourer-moth  flies  in  the  daytime.  In 
this  family  there  are  various  species  whose  females  have  the 
wings  small  and  unfit  for  flight,  the  Insects  being  very  sluggish, 
and  their  bodies  very  heavy.  This  is  the  state  of  the  female  of 
the  Vapourer-moth.  The  males  in  these  cases  are  generally  re- 
markably active,  and  very  rapid  on  the  wing. 

Some  of  these  moths  increase  in  numbers  to  an  enormous 
extent,  and  commit  great  ravages.  Psilura  monacha — the  Nun, 
"  die  Nonne  "  of  the  Germans,1 — is  one  of  the  principal  troubles  of 
the  conservators  of  forests  in  Germany,  and  great  sums  of  money 
are  expended  in  combating  it ;  all  sorts  of  means  for  repressing 
it,  including  its  infection  by  fungi,  have  been  tried  in  vain.  The 
caterpillars  are,  however,  very  subject  to  a  fungoid  disease,  com- 
municated by  natural  means.  It  is  believed,  too,  that  its  con- 
tinuance in  any  locality  is  checked  after  a  time  by  a  change 
in  the  ratio  of  the  two  sexes.  It  is  not  a  prolific  moth,  for  it 
lays  only  about  100  eggs,  but  it  has  been  shown  that  after 
making  allowance  for  the  numerous  individuals  destroyed  by 
various  enemies,  the  produce  of  one  moth  amounts  in  five  genera- 
tions to  between  four  and  five  million  individuals.  The  larva 
feeds  on  Coniferae,  and  on  many  leafy  trees  and  shrubs.  The  young 

1  This  moth  is  known  under  several  generic  names — Psilura,  Liparis,  Ocneria, 
Lymantria  ;  there  is  now  a  very  extensive  literature  connected  with  it.  A  good 
general  account  by  A\7achtl  may  be  found  in  Jf'ien.  ent.  Zeit.  x.  1891,  pp.  149-180, 
2  Plates. 


408  LEPIDOPTERA 


CHAP. 


larva  is  provided  with  two  sets  of  setae,  one  set  consisting  of  very 
long  hairs,  the  other  of  setae  radiating  from  warts  ;  each  one  of  this 
second  set  of  spines  has  a  small  bladder  in  the  middle,  and  it  has 
been  suggested  that  these  assist  in  the  dissemination  of  the  young 
caterpillars  by  atmospheric  means.1  These  aerostatic  setae  exist 
only  in  the  young  larva.  The  markings  of  the  moth  are  very 
variable  ;  melanism  is  very  common  both  in  the  larva  and  imago  ; 
it  has  been  shown  conclusively  that  these  variations  are  not 
connected,  as  black  larvae  do  not  give  a  larger  proportion  of  black 
moths  than  light-coloured  caterpillars  do.  In  England  this 
moth  is  never  injurious.  A  closely  allied  form,  Ocneria  dispar, 
was  introduced  by  an  accident  into  North  America  from  Europe 
about  thirty  years  ago  ;  for  twenty  years  after  its  introduction  it 
did  no  harm,  and  attracted  but  little  attention  ;  it  has,  however, 
now  increased  so  much  in  certain  districts  that  large  sums  of 
money  have  been  expended  in  attempting  its  extirpation. 

DasycMra  pudilmnda  has  occasionally  increased  locally  to  an 
enormous  extent,  but  in  the  limited  forests  of  Alsace  the  evil  was 
cured  by  the  fact  that  the  caterpillars,  having  eaten  up  all  the 
foliage,  then  died  of  starvation.2  Team  melanosticta  is  said  to 
produce  columns  of  processionary  caterpillars  in  Australia. 

Fam.  33.  Hypsidae  (or  Aganaidae). — -A  family  of  compara- 
tively small  extent,  confined  to  the  tropical  and  sub-tropical 
regions  of  the  Eastern  hemisphere.  The  colours  are  frequently 
huff  and  grey,  with  white  streaks  on  the  outer  parts  of  the  wings. 
We  have  nothing  very  like  them  in  the  European  fauna,  our 
species  of  Spilosoma  are  perhaps  the  nearest  approach.  In 
Euplocia  the  male  has  a  pouch  that  can  be  unfolded  in  front  of 
the  costa  at  the  base  of  the  anterior  wing;  it  is  filled  with  very 
long,  peculiar,  hair-like  scales  growing  from  the  costal  margin  ;. 
both  sexes  have  on  each  side  of  the  second  abdominal  segment 
a  small,  projecting  structure  that  may  be  a  sense-organ.  The 
female  is  more  gaily  coloured  than  the  male. 

Fam.  34.  Arctiidae. — With  the  addition  recently  made  to 
it  of  the  formerly  separate  family  Lithosiidae,  Arctiidae  has 
become  the  most  extensive  family  of  the  old  liombycid  series  of 
moths,  comprising  something  like  500  genera  and  ,'5000  species. 
Hampson  recognises  four  sub-families — Arctiinae,  Lithosiinae, 

1  WacLtl  and  Kornauth,  Mitt,  for  si.  Fer.s //<•// .sv/v.sc/t  Osterreichs,  Heft  xvi.  1893. 
'-'  Crahay,  Ann.  Hoc.  cut.  L'clyiijttc,  xxxvii.  1893,  p.  282. 


vi  HETEROCERA— -ARCTIIDAE  409 

Nolinae,  Nycteolinae, — to  which  may  be  added  others  from 
America — Pericopiiiae,  Dioptiuae,  Ctenuchinae;  these  sub-families 
being  treated  as  families  by  various  authors.  The  sub-family 
Arctiinae  includes  our  Tiger-  and  Ermine -moths,  and  a  great 
many  exotic  forms  of  very  diverse  colours  and  patterns ;  the 
species  of  this  division  are,  on  the  whole,  probably  more  variable 
in  colour  and  markings  than  in  any  other  group  of  Lepidoptera. 
There  are  many  cases  of  great  difference  of  the  sexes ;  in  the 
South  American  genus  Ambryllis  the  male  is  remarkable  for  its 
hyaline  wings  with  a  few  spots ;  while  the  female  is  densely 
scaled,  and  very  variegate  in  colour.  There  are  some  cases  (the 
South  European  genus  Ocnogytui)  where  the  female  is  wingless 
and  moves  but  little,  while  the  male  flies  with  great  rapidity. 
Epicansis  smithi,  from  Madagascar,  one  of  the  most  remarkable 
of  moths,  is  placed  in  this  division  of  Arctiidae  ;  it  is  of  a  tawny 
colour,  variegate  with  black  ;  the  abdomen  of  this  latter  colour 
is  terminated  by  a  large  tuft  of  long  scarlet  hairs;  the  Insect 
has  somewhat  the  appearance  of  a  Hummingbird -hawkmoth. 
Ecpantheria  is  an  extensive  genus  of  tropical  American  moths 
(having  one  or  two  species  in  North  America),  of  black  and 
white  or  grey  colours,  with  very  complex  markings ;  the  male  in 
some  species  has  a  part  of  the  hind  wing  produced  as  a  tail,  or 
lobe,  of  a  different  colour. 

The  sub- family  Pericopiiiae  are  almost  peculiar  to  South 
America  (two  species  of  Gnophaela  exist  in  North  America) ; 
some  of  this  sub-family  bear  a  great  resemblance  to  Heliconiid 
butterflies. 

The  Dioptinae  are  likewise  American  moths  of  diurnal  habits, 
and  many  of  them  bear  a  striking  resemblance  to  the  Ithomiid 
butterflies  they  associate  with  when  alive. 

The  sub -family  Lithosiinae  is  of  great  extent ;  our  native 
'  Footmen  "  give  a  very  good  idea  of  it :  the  moths  are  generally 
of  light  structure,  with  long,  narrow  front  wings  ;  a  simple  system 
of  yellow  and  black  colour  is  of  frequent  occurrence.  Many  of 
this  group  feed  in  the  larval  state  on  lichens.  Hainpson  includes 
in  this  group  the  Nyctemeridae — light-bodied  diurnal  moths, 
almost  exclusively  of  black  and  white  colours,  of  Geometrid 
form,  frequently  treated  as  a  distinct  family. 

The  sub-family  Nolinae  is  a  small  group  of  rather  insignificant 
Insects,  in  appearance  like  Pyralids  or  Geometrids  ;  four  or  five 


4IO  LEPIDOPTERA  CHAP. 

species  are  native   in  Britain.       Packard   maintains    the   family 
Nolidae  as  distinct.1 

The  sub-family  Xycteolinae  consists  of  a  few  small  moths  the 
position  of  which  has  always  been  uncertain;  Nycteola  (better 
known  as  Sarrothripus),  If  alias,  and  Earias  are  all  British  genera 
that  have  been  placed  amongst  Tortrices,  to  which  they  bear  a 
considerable  resemblance.  Sarrothripus  is  at  present  placed  by 
Hampsoii  in  Xoctuidae,  by  others  in  Lithosiidae,  by  Meyrick  in 
Arctiidae.  The  sub-family  forms  the  family  Cymbidae  of  Kirby;2 
it  includes  at  present  only  about  70  species,  all  belonging  to  the 
Eastern  hemisphere.  Two  types  of  larvae  are  known  in  it :  one 
bare,  living  exposed  on  leaves ;  the  other,  Earias,  hairy,  living 
among  rolled-up  leaves.  Halias  prasinana  is  known  from  the 
testimony  of  numerous  auditors  to  produce  a  sound  when  on  the 
wing,  but  the  modus  operandi  has  not  been  satisfactorily  ascer- 
tained. Sound-production  seems  to  be  of  more  frequent  occurrence 
in  Arctiidae  than  it  is  in  any  other  family  of  Lepidoptera : 
Dionychopus  nirr-ns  produces  a  sound  by,  it  is  believed,  friction 
of  the  wings.  In  the  case  of  the  genera  Setina  and  Chrlonia 
the  process  is  said  to  be  peculiar  to  the  male  sex  :  Laboulbene 
believes  it  to  proceed  from  drum-like  vesicles  situate  one  on  each 
side  of  the  base  of  the  metathorax.3 

Fam.  35.  Agaristidae. — An  interesting  assemblage  of  moths, 
many  of  them  diurnal  and  of  vivid  colours,  others  crepuscular. 
There  is  considerable  variety  of  appearance  in  the  family,  although 
it  is  but  a  small  one,  and  many  of  its  members  remind  one  of 
other  and  widely  separated  families  of  Lepidoptera.  The  style 
and  colour  of  the  Japanese  Euscmia  villieoides  are  remarkably 
like  our  Arctia  villica.  In  some  forms  the  antennae  are  some- 
what thickened  towards  the  tip  and  hooked,  like  those  of  the 
Skipper  butterflies.  The  family  consists  at  present  of  about  250 
species,  but  we  doubt  its  being  a  sufficiently  natural  one.  It  is 
very  widely  distributed,  with  the  exception  that  it  is  quite  absent 
from  Europe  and  the  neighbourhood  of  the  Mediterranean  Sea. 
fn  North  America  it  is  well  represented.  The  larvae,  so  far  as 
known,  are  not  very  remarkable;  they  have  some  lateral  tufts  of 
hair,  as  well  as  longer  hairs  scattered  over  the  body. 

1  Amcr.  Natural,  xxix.  1895,  p.  801. 

-  Catalogue  of  Lepidopterct  Heterocera,  i.  1892. 

3  Ann.  &>c.  cut.  France  (4),  iv.  1864,  p.  689. 


vi  HETEROCERA AGARISTIDAE GEOMETRIDAE  4!  I 

The  male  of  the  Indian  Acyocera  tripartita  has  been  noticed 
to  produce  a  clicking  sound  when  flying,  and  Sir  G.  Hampson  has 
shown  :  that  there  is  a  peculiar  structure  on  the  anterior  wing ; 
he  considers  that  this  is  rubbed  against  some  spines  on  the  front 
feet,  and  that  the  sound  is  produced  by  the  friction.  Though 
this  structure  is  wanting  in  the  acknowledged  Congeners  of 
A.  fi-ipm-tita,  yet  it  occurs  in  a  very  similar  form  in  the  genus 
Hccntcsin,  already  noticed  under  Castniidae. 

Fam.  36.  Geometridae  (Carpets,  Pugs,  efr.)--This  very 
extensive  family  consists  of  fragile  moths,  only  a  small  number 
being  moderately  stout  forms  ;  they  have  a  large  wing  -  area  ; 
the  antennae  are  frequently  highly  developed  in  the  males, 
but  on  this  point  there  is  much  diversity.  Either  the  frenulum 
or  the  proboscis  is  absent  in  a  few  cases.  The  caterpillars  are 
elongate  and  slender,  with  only  one  pair  of  abdominal  feet- 
placed  on  the  ninth  segment — in  addition  to  the  anal  pair,  or 
claspers.  They  progress  by  moving  these  two  pairs  of  feet  up  to 
the  thoracic  legs,  so  that  the  body  is  thrown  into  a  large  loop,  and 
they  are  hence  called  Loopers  or  Geometers.  The  family  is  uni- 
versally distributed,  and  occurs  even  in  remote  islands  and  high 
latitudes  ;  in  Britain  we  have  about  270  species.  The  family  was 
formerly  considered  to  be  closely  connected  with  Noctuidae,  but  at 
present  the  opinion  that  it  has  more  intimate  relations  with  the 
families  we  have  previously  considered  is  prevalent.  Packard 
considers  it  near  to  Lithosiidae,  while  Meyrick  merely  places  the 
six  families,  of  which  he  treats  it  as  composed,  in  his  series  Noto- 
dontina.  Hampson  adopts  Meyrick's  six  families  as  sub-families, 
but  gives  them  different  names,  being  in  this  respect  more  con- 
servative than  Meyrick,  whose  recent  revision  of  the  European 
forms  resulted  in  drastic  changes  in  nomenclature.'2  This 
classification  is  based  almost  exclusively  on  wing-nervuration. 
The  number  of  larval  legs  and  the  consequent  mode  of  walking 
is  one  of  the  most  constant  characters  of  the  group  ;  the  few 
exceptions  that  have  been  detected  are  therefore  of  interest. 
Anisopteryx  aescularia  has  a  pair  of  undeveloped  feet  on  the  eighth 
segment,  and,  according  to  Meyrick,  its  allies  "  sometimes  show 
rudiments  of  the  other  two  pairs."  The  larva  of  Him  era 

1  P.  Zool.  Soc.  London,  1892,  p.  188. 

1   Tr.  cnt.  Soc.  London,   1892,  pp.  53-140  ;    for  critic-ism  on  the  nomenclature, 
see  Rebel,  Ent.  Zeit.  Stettin,  Hii.  1892,  p.  247. 


4I2 


LEPIDOPTERA 


CHAP. 


/ii'/itiaria  is  said  to  have  in  early  life  a  pair  of  imperfect  feet  on 
the  eighth  segment,  which  disappear  as  the  larva  approaches 
maturity. 

The  position  of  the  abdominal  feet  and  claspers  throws  the 
holding  power  of  the  larva  to  the  posterior  part  of  the  body, 
instead  of  to  the  middle,  as  in  other  caterpillars.  This,  com- 
bined with  the  elongate  form,  causes  these  larvae  when  reposing 
to  assume  attitudes  more  or  less  different  from  those  of  other 
larvae  ;  holding  on  by  the  claspers,  some  of  these  Insects  allow  all 
the  anterior  parts  of  the  body  to  project  in  a  twig-like  manner. 
The  front  parts  are  not,  however,  really  free  in  such  cases,  but 
are  supported  by  a  thread  of  silk  extending  from  the  mouth 
to  some  point  near-by.  Another  plan  adopted  is  to  prop  the 

front  part  of  the  body 
against  a  twig  placed 
at  right  angles  to  the 
supporting  leaf,  so  that 
the  caterpillar  is  in  a 
diagonal  line  between 
the  two  (Fig.  202). 
Other  Geometers  assume 
peculiar  coiled  or  spiral 
attitudes  during  a  whole 
or  a  portion  of  their 
lives ;  some  doing  this 
on  a  supporting  object 
—leaf  or  twig — while 
others  hang  down 
(Epliyra  pendularici}. 
Certain  of  the  larvae  of 
Geometridae  vary  in 
colour,  from  shades  of 
brown  to  green;  there 
is  much  diversity  in 
this  variation.  In  some 


FIG.  202.  —  Larva  of 

oil  a  rose-twig. 


reposin 


x  1.      Cambridge. 


species  it  is  simple  variation  ;  in  others  it  is  dimorphism, 
i.e.  the  larvae  are  either  brown  or  green.  In  other  cases  the 
larvae  are  at  first  variable,  subsequently  dimorphic.  In  AmpJn- 
dasi*  I,  I ul ,i ri<i  it  would  appear  that  when  the  larva  is  hatched 
the  dimorphism  is  potential,  and  that  the  future  colour,  whether 


vi  GEOMETRIDAE  413 

green  or  brown,  is  settled  by  some  determining  condition  during 
the  first  period  of  larval  life  and  cannot  be  subsequently  modified.1 
According  to  Poulton,  the  dark  tint  is  due  in  A.  betularia  to 

o 

colouring  matter  in  the  skin  or  immediately  below  it,  and  the 
green  tint  to  a  layer  of  fat  between  the  hypodermis  and  the 
superficial  muscles ;  this  layer  being  always  green,  but  more 
brightly  green  in  the  larvae  that  are  of  this  colour,  externally. 
Much  discussion  has  occurred  about  these  larval  attitudes  and 
colours,  and  it  seems  probable  that  Professor  Poulton  has  over- 
rated the  value  of  protection  from  birds,  mammals  and  ento- 
mologists ;  the  chief  destroying  agents  being  other  than  these, 
and  not  liable  to  be  thus  deceived,  even  if  the  vertebrates  are. 
In  some  cases  such  resemblance  as  undoubtedly  exists  is  not 
made  the  best  use  of.  The  larva  shown  in  figure  202  bore 
a  wonderful  resemblance,  when  examined,  to  the  rose-twigs  it- 
lived  on,  but  the  effect  of  this  as  a  concealing  agent  was  entirely 
destroyed  by  the  attitude  ;  for  this,  being  on  different  lines  to 
those  of  the  plant,  attracted  the  eye  at  once.  This  larva,  and  we 
may  add  numerous  other  larvae,  could  have  been  perfectly  con- 
cealed by  adopting  a  different  attitude,  but  never  did  so  ;  the 
position  represented  being  constantly  maintained  except  while 
feeding. 

In  some  species  of  this  family  the  adult  females  are  without 
wings,  or  have  them  so  small  that  they  can  be  of  no  use  for 
flight.  This  curious  condition  occurs  in  various  and  widely- 
separated  groups  of  the  Geometridae  ;  and  it  would  be  naturally 
supposed  to  have  a  great  effect  on  the  economy  of  the  species 
exhibiting  it,  but  this  is  not  the  case.  Some  of  the  flightless 
females  affect  the  highest  trees  and,  it  is  believed,  ascend  to  their 
very  summits  to  oviposit.  It  has  been  suggested  that  they  are 
carried  up  by  the  winged  males,  but  this  is  probably  only  an 
exceptional  occurrence  ;  while,  as  they  are  known  to  lie  capable 
of  ascending  with  rapidity  by  means  of  crawling  and  running, 
it  may  be  taken  for  granted  that  this  is  the  usual  method  with 
them.  Some  of  these  wingless  females  have  been  found  in 
numbers  on  gas-lamps,  and  are  believed  to  have  been  attracted 
by  the  light,  as  is  the  case  with  very  many  of  the  winged  forms.2 

1  See  Poulton,  Tr.   cnt.   Soc.  London,  1SS4,  p.  51  ;    op.   cit-  1892>   P-   293  5  aUl1 
Bateson,  p.  213  ;  Gould,  p.  215. 

2  Girawl,  Ann.  Soc.  ent.  France  (4),  v.  1865,  p.  105  ;  Fauvel,  I.e.  Bull.  p.  liii. 


414  LEPIDOPTERA  CHAP. 

Neither  is  the  geographical  distribution  limited  by  this  inferior 
condition  of  the  most  important  of  the  organs  of  locomotion,  for 
CheimatoMa  brumata  (the  Winter-moth)  one  of  the  species  with 
flightless  female,  is  a  common  and  widely  distributed  Insect  in 
Europe  and  North  America. 

Although  the  classification  of  this  family  is  based  almost 
entirely  on  wing-nervuration,  yet  there  are  some  divisions  of  the 
Geometridae  in  which  this  character  is  remarkably  variable, 
certain  individuals  frequently  exhibiting  considerable  abnor- 
mality.1 Amplildasis  l»tnlur'u<  is  believed  to  have  changed  its 
variation  considerably  in  the  course  of  the  last  fifty  years.  Pre- 
vious to  that  time  a  black  variety  of  the  species  was  unknown, 
but  it  has  now  become  common  ;  and  it  is  believed  that  other 
species  of  Geometridae  are  in  process  of  exhibiting  a  similar 
phenomenon.2 

Fam.  37.  Noctuidae  (Owlet -Moths,  Eulen  of  the  Germans). 
-This  very  extensive  assemblage  consists  of  moths  rarely  seen 
in  the  day-time,  of  generally  sombre  colours,  with  antennae  desti- 
tute of  remarkable  developments  in  the  male  (except  in  a  small 
number  of  forms) ;  proboscis  and  frenulum  both  present ;  a  com- 
plex sense-organ  on  each  side  of  the  body  at  the  junction  of  the 
metathorax  and  abdomen.  The  number  of  species  already  known 
can  scarcely  be  less  than  8000  ;  owing  to  their  large  numbers 
and  the  great  general  resemblance  of  the  forms,  their  classifica- 
tion is  a  matter  of  considerable  difficulty.  Although  the  peculiar 
structure  at  the  base  of  the  thorax  was  long  since  pointed  put, 
it  has  never  received  any  thorough  investigation.  Few  other 
remarkable  structures  have  yet  been  discovered:  the  most  in- 
teresting is  perhaps  the  peculiarity  in  the  hind  wings  of  the 
males  of  certain  Ommatophorinae  recently  pointed  out  by  Sir 
G.  F.  Hampson  3  :  in  the  genera  Patula  and  Arijini  the  form  of 
the  hind  wings  is  normal  in  the  females,  but  in  the  male  the 
anterior  one-half  of  each  of  these  wings  is  aborted,  and  the 
position  of  the  nervures  changed ;  this  condition  is  connected 
with  the  development  of  a  glandular  patch  or  fold  on  the  wing, 
and  is  remarkable  as  profoundly  affecting  a  structure  which  is 

1  For  a  table,  see  Meyrick,  I.e. 

-   Barrett,  "Increasing  Melanism  in  British  Geometridae,"  Ent.  Monthly  May. 
L895,  i>.  198. 

a  J'.  Zwl.  tioc.  London,  1892,  p.  192. 


VI 


NOCTUIDAE 


415 


otherwise  so   constant    that    the    classification   of  the    family  is 
largely  based  on  it. 

The  larvae  are  as  a  rule  destitute  of  the  remarkable  adorn- 
ments of  hairs  and  armatures  of  spines  that  are  so  common  in 
many  of  the  families  we  have  previously  considered  ;  they  are 
fond  of  concealing  themselves  during  the  day  and  coming  out  at 
night  to  feed  ;  many  of  them  pass  most  of  their  time  at,  or 
beneath,  the  surface  of  the  ground,  finding  nourishment  in  roots 
or  the  lower  parts  of  the  stems  of  plants  ;  this  is  notably  the 
case  in  the  genus  Agrotis,  which  is  perhaps  the  most  widely 
distributed  of  all  the  genera  of  moths.  Such  caterpillars  are 
known  as  Cut-worms  in  North  America.1  The  great  resemblance, 
inter  se,  of  certain  of  these  Out-worms,  much  astonished  the 
American  naturalist  Harris,  who  found  that  larvae  almost  per- 
fectly similar  produced  very  different  moths.  The  majority  of 
Noctuid  larvae  have  the  usual  number  of  legs,  viz.,  three  pairs 
of  thoracic  legs,  four  pairs  of  abdominal  feet  and  the  terminal 
claspers.  In  some  divisions  of  the  family  there  is  a  departure 
from  this  arrangement,  and  the  abdominal  feet  are  reduced  to 
three,  or  even  to  two,  pairs.  One  or  two  larvae  are  known — e.g. 
Eiididiti  mi — in  which  the  claspers  have  not  the  usual  function, 
but  are  free  terminal  appendages.  When  the  abdominal  legs 
are  reduced  in  number  (Plusia,  e.g.)  the  larvae  are  said  to  be 
Half-loopers,  or  Semi-loopers,  as  they  assume  to  some  extent  the 
peculiar  mode  of  progression  of  the  Geometrid  larvae,  which  are 
known  as  Loopers.  In  the  case  of  certain  larvae,  e.g.  Triphaena, 
that  have  the  normal  number  of  feet,  it  has  been  observed  that 
when  first  hatched,  the  one  or  two  anterior  pairs  of  the  abdom- 
inal set  are  ill  developed,  and  the  larvae  do  not  use  them  for 
walking.  This  is  the  case 
with  the  young  larva  of  our 
British  Brephos  notha  (Fig. 
203).  Subsequently,  how- 
ever, this  larva  undergoes 
a  considerable  change,  and 
appears  in  the  form  shown 
in  Fig.  204.  This  interesting  larva  joins  together  two  or  three 

1  Although  this  term  is  widely  used  in  Xorth  America,  it  is  not  in  use  in  Eng- 
land, though  it  may  possibly  have  originated  in  Scotland.  See  Slingerlaiid,  Bull. 
Cornell  University  Exp.  8tat.  104,  1895,  p,  555. 


FIG.  203. — Brephos  notha.     Larva,  newly 
hatched.      Britain. 


416 


LEPIDOPTERA 


CHAP. 


leaves  of  aspen  and  lives  between  them,  an  unusual  habit  for 
Noctuid  larvae.  When  about  to  pupate  it  bores  into  bark  or 
soft  wood  to  change  to  a  pupa,  Fig.  205  ; 
the  specimen  represented  closed  the  hole  f 
of  entry  by  placing  two  separate  doors 
of  silk  across  the  burrow,  as  shown  at  d. 
The  anal  armature  of  this  pupa  is  ter- 
minated by  a  curious  transverse  process. 
The  systematic  position  of  this  inter- 


FIG.  20-i. — Brephos  notha.     Adult  larva. 


FIG.  205. — Brephos  notha.  A, 
Pupa,  ventral  aspri-t  ;  B. 
extremity  of  body,  magni- 
fied ;  C,  the  pupa  in  word  ; 
(/,  diaphragms  constructed 
by  the  larva. 


esting  Insect  is  very  uncertain  :   Meyrick  and  others  associate  it 
with  the  Geonietridae. 

The  larva  of  Leucania  unipunctata  is  the  notorious  Army- 
worm  that  commits  great  ravages  on  grass  and  corn  in  Xorth 
America.  This  species  sometimes  increases  in  numbers  to  a  con- 
siderable extent  without  being  observed,  owing  to  the  retiring- 
habits  of  the  larvae ;  when,  however,  the  increase  of  numbers 
has  been  so  great  that  food  becomes  scarce,  or  for  some  other 
cause — -for  the  scarcity  of  food  is  supposed  not  to  be  the  only 
reason — the  larvae  become  gregarious,  and  migrate  in  enormous 
swarms:  whence  its  popular  name.  The  Cotton-worm,  Alcti« 
xylinae  is  even  more  notorious  on  account  of  its  ravages.  Eiley 
states  l  that  in  bud  years  the  mischief  it  commits  on  the  cotton 
crop  causes  a  loss  of  £0,000,000,  and  that  for  a  period 
of  fourteen  successive  years  the  annual  loss  averaged  about 
£3,000,000.  This  caterpillar  strips  the  cotton  plants  of  all  but 
their  branches.  It  is  assisted  in  its  work  by  another  highly 
destructive  Noctuid  caterpillar,  the  Boll -worm,  or  larva  of 
armigera,  which  bores  into  the  buds  and  pods.  This 

h  l!<i>.  U. X  E/it.  Commission,  1885,  p.  3. 


vi  HETEROCERA NOCTUIDAE  417 

latter  Insect  attacks  a  great  variety  of  plants,  and  has  a  very 
wide  distribution,  being  found  even  in  England,  where  happily 
it  is  always  a  rare  Insect. 

In  Britain,  as  well  as  in  parts  of  Northern  Europe,  a  Noctuid 
moth,  Charaeas  graminis,  occasionally  increases  to  an  enormous 
extent :  its  larva  is  called  the  Hill-grub  and  lives  on  the  grass  of 
pastures,  frequently  doing  great  damage  in  hill-lands.  The  in- 
crease of  this  moth  seems  to  take  place  after  the  manner  of  an 
epidemic  ;  a  considerable  number  of  years  may  pass  during  which 
it  is  scarcely  seen,  and  it  will  then  appear  in  unusual  numbers 
in  widely  separated  localities.  This  moth  lays  a  large  number 
of  eggs,  and  is  not  completely  nocturnal  in  habits  ;  sometimes  it 
may  be  seen  on  the  wing  in  great  numbers  in  the  hottest  sun- 
shine, and  it  has  been  noticed  that  there  is  then  a  great  dispro- 
portion of  the  sexes,  the  females  being  ten  or  twenty  times  as 
numerous  as  the  males.  In  Australia,  the  Bugong  moth,  Agrotis 
spina,  occurs  in  millions  in  certain  localities  in  Victoria :  this 
moth  hibernates  as  an  imago,  and  it  formerly  formed,  in  this 
instar,  an  important  article  of  food  with  the  aborigines.  The 
powers  of  increase  of  another  Xoctuicl  moth — Erastria  scitula 
—are  of  great  value.  Its  habits  have  been  described  by 
Eouzaud.1  On  the  shores  of  the  Mediterranean  the  larva  of  this 
little  moth  lives  on  a  Scale-Insect — Lecanium  oleae — that  infests 
the  peach ;  and  as  the  moth  may  have  as  many  as  five  genera- 
tions in  a  year,  it  commits  laudable  havoc  with  the  pest.  The 
larva  is  of  remarkable  form,  very  short  and  convex,  with  small 
head,  and  only  two  pairs  of  abdominal  feet.  The  scale  of  the 
Lecanium  is  of  larger  size  than  is  usual  in  that  group  of  Insects, 
and  the  young  larva  of  the  Erastria  buries  itself,  as  soon  as 
hatched,  in  one  of  the  scales  ;  it  destroys  successively  numerous 
scales,  and  after  having  undergone  several  moults,  it  finds  itself 
provided,  for  the  first  time,  with  a  spinneret,  when,  with  the  aid 
of  its  silk,  it  adds  to  and  adapts  a  Coccid  scale,  and  thus  forms  a 
portable  habitation  ;  this  it  holds  on  to  by  means  of  the  pair  of 
anal  claspers,  which  are  of  unusual  form.  The  case  is  afterwards 
subjected  to  further  alteration,  so  that  it  may  serve  as  a  protec- 
tion to  the  creature  when  it  has  changed  to  a  pupa.  This  moth 
is  said  to  be  free  from  the  attacks  of  parasites,  and  if  this  be  the 
case  it  is  probable  that  its  increase  is  regulated  by  the  fact  that 

1  Insect  Life,  vi.  1894  p.  6. 
VOL.  VI  2  E 


41 8  LEPIDOPTERA 


CHAP. 


when  the  creature  becomes  numerous  it  thus  reduces  the  food 
supply,  so  that  its  own  numbers  are  afterwards  in  consequence 
diminished. 

One  of  the  most  remarkable  genera  of  British  Noctuidae  is 
Acronycta,1  the  larvae  of  which  exhibit  so  much  diversity  that  it 
has  been  suggested  that  the  genus  should  be  dismembered  and  its 
fragments  treated  as  allied  to  several  different  divisions  of  moths. 
There  are  many  points  of  interest  in  connection  with  the  natural 
history  of  these  Acronycta.  A.  psi  and  A.  tridens  are  practically 
indistinguishable  as  moths,  though  the  larvae  are  easily  separated  : 
the  former  species  is  said  to  be  destroyed  to  an  amazing  extent 
by  parasites,  yet  it  remains  a  common  Insect.  The  genus 
Apatela  is  very  closely  allied  to  Acronycta,  and  Harris  says  that 
'  Apatda  signifies  deceptive,  and  this  name  was  probably  given  to 
the  genus  because  the  caterpillars  appear  in  the  dress  of  Arctians 
and  Liparians,  but  produce  true  owlet-moths  or  Noctuas."  The 
species  of  another  British  genus,  Brybphila,  possess  the  excep- 
tional habit  of  feeding  on  lichens.  Some  of  the  American  group 
Erebides  are  amongst  the  largest  Insects,  measuring  seven  or 
eight  inches  across  the  expanded  wings. 

The  Deltoid  moths  are  frequently  treated  as  a  distinct  family, 
Deltoidae,  perhaps  chiefly  because  of  their  res'emblance  to  Pyra- 
lidae.  At  present,  however,  they  are  considered  to  be  separated 
from  Noctuidae  by  no  valid  characters. 

Fam.  38— Epicopeiidae. — The  genus  Epicopeia,  consists  of 
only  a  few  moths,  but  they  are  amongst  the  most  extraordinary 
known  :  at  first  sight  they  would  be  declared  without  hesitation 
to  be  large  swallow-tail  butterflies,  and  Hampson  states  that  they 
••  mimic "  the  Papilios  of  the  Polijxenus  group.  Very  little  is 
known  about  these  extremely  rare  Insects,  but  the  larva  is  stated, 
on  the  authority  of  Mr.  Dudgeon,  to  surpass  the  moths  themselves 
in  extravagance  ;  to  be  covered  with  long  processes  of  snow-white 
efflorescence,  like  wax,  exuded  from  the  skin,  and  to  "  mimic  "  a 
colony  of  the  larva  of  a  Homopterous  Insect.  Some  ten 
'species  of  this  genus  are  known  from  Java,  India,  China,  and 
Japan.  In  this  family  there  is  said  to  be  a  rudimentary  frenu- 
lum,  but  it  is  doubtful  whether  the  hairs  that  have  given  rise  to 
this  definition  really  justify  it. 

1  Sc-i-  < 'li.'ipniaii,  The  Genus  Acronycta  and  UK  Allies,  London,  1893. 
2  Insects  Injurious,  etc.,  Ed.  18(52,  Boston,  p.  437. 


VI 


HETEROCERA — URANIIDAE 


419 


Fam.  39.  Uraniidae. — A  family  of  small  extent,  including 
light-bodied  moths  with  ample  wings  and  thread-like  antennae ; 
most  of  them  resemble  Geometridae,  but  a  few  genera,  Urania 
and  Nyctalcmon,  are  like  Swallow-tail  butterflies  and  have 
similar  habits.  The  Madagascar  moth,  Chrysiridia  inadagascar- 
iensis  (better  known  as  Urania  rhipheus],  is  a  most  elegant  and 
beautiful  Insect,  whose  only  close  allies  (except  an  East  African 
congener)  are  the  tropical  American  species  of  Urania,  which 
were  till  recently  treated  as  undoubtedly  congeneric  with  the 
Madagascar  moth.  The  family  consists  of  but  six  genera  and 
some  sixty  species.  The  question  of  its  affinities  has  given  rise 
to  much  discussion,  but  on  the  whole  it  would  appear  that  these 
Insects  are  least  ill-placed  near  Xoctuidae.1  The  larva  of  the 
South  American  genus  Coro- 
nidia  is  in  general  form  like 
a  Noctuid  larva,  and  has  the 
normal  number  of  legs ;  it 
possesses  a  few  peculiar  fleshy 
processes  on  the  back.  A 
description  of  the  larva  of 
Chi  'ysii  'idia  madagasc  ari  ensis 
has  been  widely  spread  ;  but 
according  to  Camboue,2  the 
account  of  the  metamorphoses, 
first  given  by  Boiscluval,  is 
erroneous.  The  larva,  it  ap-  8 
pears,  resembles  in  general 
form  that  of  Coronidia,  and  FIG-  206. —Abdomen  of  ci* -,•>/.•*; ,->,t>,i  mada- 

A,  Horizontal  section  show- 


gascanensis, 

ing  the  lower  part  of  the  male  abdomen  : 
1,  first  segment  ;  2,  spiracle  of  second 
segment  ;  4-8,  posterior  segments.  B, 
the  abdomen  seen  from  the  side,  with  the 


segments  numbered.     The  section  is  that 
of  an  old,  dried  specimen. 


has  sixteen  feet ;  it  is,  how- 
ever, armed  with  long,  spatu- 
late  black  hairs ;  it  changes  to 
u  pupa  in  a  cocoon  of  open 
network. 

In  all  the  species  of  this  family  we  have  examined,  we  have 
noticed  the  existence  of  a  highly  peculiar  structure  that  seems 
hitherto  to  have  escaped  observation.  On  each  side  of  the 
second  abdominal  segment  there  is  an  ear-like  opening  (usually 

1  See  "\Vestwood,  Tr.  Zool.  Soc.  London,  x.   pp.  507,  etc.,  for  discussion  of  this 
question  and  for  figures  ;  also  E.  Renter,  Act.  Soc.  Sci.  Fcnn.  xxii.  1896,  p.  202. 
-  Cony r.  Internal.  Zool.  ii.  1892,  pt,  2,  p.  180. 


420  LEPIDOPTERA  CHAP. 

much  concealed  by  overlapping  scales),  giving  entrance  to  a 
chamber  in  the  body  ;  this  chamber  extends  to  the  middle  line, 
being  separated  from  its  fellow  by  only  a  thin  partition.  At 
its  anterior  and  lateral  part  there  is  a  second  vesicle-like 
chamber,  formed  by  a  delicate  membrane  that  extends  as  far 
forwards  as  the  base  of  the  abdomen.  There  can  be  little  doubt 
that  this  is  part  of  some  kind  of  organ  of  sense,  though  it  is 
much  larger  than  is  usual  with  Insect  sense-organs. 

Fam.  40.  Epiplemidae.  —  Under  this  name  Hampson  has 
assembled  certain  Geometroid  moths,  some  of  them  placed  previ- 
ously in  Chalcosiidae,  some  in  Geometridae.  They  form  a  varied 
group,  apparently  closely  allied  to  Uraniidae,  and  having  a  similar 
peculiar  sense-organ  ;  but  are  distinguished  by  the  presence  of  a. 
frenulum.  The  larva  seems  to  be  like  that  of  Uraniidae. 

Fam.  41.  Pyralidae.  —  This  division  is  to  be  considered  rather 
as  a  group  of  families  than  as  a  family  ;  it  includes  a  very  large 
number  of  small  or  moderate-sized  moths  of  fragile  structure, 
frequently  having  long  legs  ;  antennae  simple,  only  in  a  few 
cases  pectinate  ;  distinguished  from  Noctuidae  and  all  the  other 
extensive  divisions  of  moths  by  the  peculiar  course  of  the  costal 
nervure  of  the  hind  wing,  which  either  keeps,  in  the  middle  of 
its  course,  near  to  the  sub-costal  or  actually  unites  with  it, 
subsequently  again  separating.  Members  of  the  Pyralidae  an- 
found  in  all  lands;  in  Britain  we  have  about  150  species.  The 
larvae  are  usually  nearly  bare,  with  only  short,  scattered  setae, 
and  little  coloration;  they  have  most  varied  habits,  are  fond  of 
concealment,  and  are  very  lively  and  abrupt  in  movement, 
wriggling  backwards  as  well  as  forwards,  when  disturbed  ;  a 
cocoon  is  formed  for  the  metamorphosis. 

The  family  as  a  whole  consists  of  Insects  of  unattractive 
appearance,  although  it  contains  some  very  elegant  and  interesting 
moths  and  numerous  forms  of  structural  interest.  In  the  genus 
Thiridopteryx  little  transparent  spaces  on  the  wings  occur  as  a 
character  peculiar  to  the  males  ;  the  spaces  are  correlative  with 
a  greater  or  less  derangement  of  the  wing-nervures.  In  some 
other  forms  there  is  a  remarkable  retinaculuin,  consisting  of  large 
si-ales,  and  this,  too,  is  connected  with  a  distortion  of  the  wing- 
nervures.  The  Pyralidae  —  Pyralites  of  Eagonot,1  Pyralidina  of 


t,  Ann.  Soc.  ent.  France,  1890  and  1891  :  and  Meyrick,   Tr.  ent.  Soc. 
London,  1890,  p.  429. 


vi  HETEROCERA PYRALIDAE  421 

Meyrick — have  recently  been  revised  by  two  naturalists  of  dis- 
tinction almost  simultaneously ;  unfortunately  their  results  are 
discrepant,  Meyrick  including  Pterophoridae  and  Orneodidae, 
and  yet  admitting  in  all  only  eight  families ;  while  Eagonot  does 
not  include  the  two  groups  named,  but  defines  seventeen  tribes 
of  the  two  families — Pyralidae  and  Crambidae — that  he  admits. 
The  Pyraustidae  of  Meyrick  is  an  enormous  division  including 
the  Hydrocampidae  and  Scopariidae  of  many  authors,  as  well  as 
the  Pyraustinae  proper  and  a  small  group  of  Poigonot's,  the 
Homophysinae.  The  division  Scopariinae  is  believed  to  be 
amongst  the  "  most  ancient "  of  Lepidoptera ;  the  food  of  the 
larvae  consists  of  moss  and  lichens.  This  group  is  widely  dis- 
tributed, being  richly  represented  in  Australia,  New  Zealand, 
and  the  Hawaiian  Islands,  as  well  as  in  Europe ;  and  probably 
really  occurs  wherever  their  food-plants  exist  accompanied  by 
a  tolerable  climate.  The  statistics  of  the  distribution  of  this 
group,  so  far  as  at  present  known,  have  been  furnished  by 
Mr.  Meyrick,  as  follows  : — European  region,  about  2  5  species  ; 
Madeira,  3  ;  St.  Helena,  0  ;  South  Africa,  2  or  3  ;  India,  9  ; 
Malayan  region,  3  or  4  ;  Australia,  24 ;  New  Zealand,  64 ; 
Hawaiian  Islands,  5  0  ;  North  America,  1 7  (one  of  them  Euro- 
pean);  South  America,  10.  The  Hydrocampinae — the  China- 
marks — are  of  great  interest,  as  being  amongst  the  few  forms 
of  Lepidoptera  adapted  for  aquatic  life.  It  is  believed  that  all 
their  larvae  are  aquatic,  though  of  only  a  few  is  there  much 
known.  The  diversity  amongst  these  forms  is  of  considerable 
interest.  The  habits  of  Jfi/drocampa  nymphaeata  were  long  since 
described  by  Reaumur,  and  have  more  recently  been  dealt  with 
by  Buckler,1  W.  Miiller  2  and  Prof.  Miall.3  Although  there  are 
some  discrepancies  in  their  accounts,  due  we  believe  to  the 
observations  being  made  at  different  periods  of  the  life  and  under 
somewhat  different  circumstances,  yet  the  account  given  by 
Miiller  is  we  feel  no  doubt  substantially  correct.  The  larvae 
when  hatched  mine  in  the  leaves  of  a  water-plant  for  a  short 
time — thirty  hours  to  three  days  according  to  Buckler — and  are 
completely  surrounded  by  water,  which  penetrates  freely  into 
their  burrows ;  at  this  period  the  caterpillar  breathes  by  its 
skin,  the  spiracles  being  very  small,  and  the  tubes  leading  from 

1  Ent.  Mag.  xii.  1876,  p.  210,  and  xvii.  1881,  p.  249. 
2  Zool.  Jahrb.  Syst.  vi.  1892,  p.  617.      3  Nut.  Hist.  Aquatic  Insects,  London,  1895. 


422  LEPIDOPTERA  CHAP. 

them  closed  and  functionless.  After  this  brief  period  of  mining 
life,  the  larva  moults  and  then  constructs  a  habitation  by  cutting 
a  piece  out  of  a  leaf,  and  fastening  it  to  the  under  side  of  another 
leaf;  it  is  thus  provided  with  a  habitation,  but  it  is  one  into 
which  the  water  freely  enters,  and  the  respiratory  apparatus 
remains  in  the  state  we  have  described.  The  Insect  passes 
through  several  moults,  and  then  hibernates  in  the  water.  On 
its  revival  in  the  spring  a  change  occurs,  and  the  larva  constructs 
a  portable,  or  we  should  rather  say  free,  habitation  out  of  two 
large  pieces  of  leaf  of  lens-shape,  fastened  together  at  the 
edges ;  but  the  larva  has  some  method  of  managing  matters  so 
that  the  water  can  be  kept  out  of  this  house ;  thus  the  creature 
lives  in  air  though  immersed  in  the  water.  A  correlative  change 
occurs  in  the  structure  of  the  skin  and  tracheal  system.  The 
former  becomes  studded  with  prominent  points  that  help  to 
maintain  a  coat  of  air  round  the  Insect,  like  dry  velvet  immersed 
in  water ;  the  spiracles  are  larger  than  they  were,  and  they  and 
the  tracheal  tubes  are  open.  One  or  two  moults  take  place  and  the 
creature  then  pupates.  There  is  a  good  deal  of  discrepancy  in 
the  accounts  of  this  period,  and  it  seems  probable  that  the  pupa 
is  sometimes  aerial,  sometimes  aquatic.  Buckler's  account  of  the 
formation  of  the  case  shows  that  the  larva  first  cuts  off,  by  an 
ingenious  process,  one  piece  of  leaf,  leaving  itself  on  this,  as  on 
a  raft :  this  it  guides  to  a  leaf  suitable  for  a  second  piece,  gets 
the  raft  underneath,  and  fastens  it  with  silk  to  the  upper  portion, 
and  then  severs  this,  leaving  the  construction  free  ;  afterwards  the 
larva  goes  through  a  curious  process  of  changing  its  position  and 
working  at  the  two  extremities  of  the  case,  apparently  with  the 
object  of  making  it  all  right  as  regards  its  capacity  for  including 
air  and  keeping  out  water.  He  believes  that  Reaumur  was 
correct  in  his  idea  that  the  larva  regulates  the  admission  of  air 
or  of  water  to  the  case  in  conformity  with  its  needs  for  respiration. 
Miiller  calls  special  attention  to  the  great  changes  in  habit  and 
in  the  structure  of  the  integument  during  the  life  of  this  larva  ; 
1'Ui  the  reader  will  gather  from  what  we  relate  as  to  various 
terrestrial  Lepidopterous  larvae,  that  these  phenomena  are  not 
very  dissimilar  from  what  frequently  take  place  in  the  latter;  a 
change  of  h.iluts  ;it  some  particular  moult,  accompanied  by  great 
changes  in  the  integument,  and  even  in  the  size  of  the  stigmata, 
being  of  frequent  occurrence. 


vr  HETEROCERA  —  PYRALIDAE  423 


The  larva  of  Xj/rnpluil«  */";//<"/",  a  close  ally  of  H.  nymphaeata, 
has  aquatic  habits  of  a  somewhat  similar  but  simpler  nature  ; 
while  N.  (Para-pony?}  sti'atintittn.  is  very  different.  This  larva  is 
provided  with  eight  rows  of  tufts  of  flexible  branchiae,  occupying 
the  position  of  the  spots  or  setigerous  warts  usual  in  caterpillars, 
and  reminding  one  of  the  spines  of  certain  butterfly-larvae,  though 
they  are  undoubtedly  respiratory  filaments.  These  caterpillars 
protect  themselves  by  forming  silken  webs  or  cases,  or  by  adopt- 
ing the  case  of  some  other  larva,  and  are  in  the  habit  of  holding 
on  by  the  anal  claspers,  and  rapidly  and  energetically  moving 
the  anterior  parts  of  the  body  in  an  undulating  fashion.  The 
spiracles  exist,  but  are  functionless.  The  pupa  lives  under  water, 
and  has  no  branchiae  ;  but  three  of  the  pairs  of  abdominal 
spiracles  are  open,  and  project  from  the  body.  Miiller  informs 
us  that  in  a  Brazilian  Paraponyx  these  three  pairs  of  spiracles 
were  already  large  in  the  larva,  though  the  other  pairs  were  very 
small,  or  absent.  He  considers  that  the  moth  of  this  species 
descends  beneath  the  water  of  a  rapid  stream,  and  fastens  its 
eggs  on  the  stems  of  plants  therein.  Cataclysta  lemnata  lives  in 
a  case  of  silk  with  leaves  of  duckweed  attached  to  it,  or  in  a 
piece  of  a  hollow  stem  of  some  aquatic  plant  ;  it  is  believed  to 
breathe,  like  H.  nympliaeata,  at  first  by  the  integument  and 
subsequently  by  open  stigmata  :  but  particulars  as  to  how  it 
obtains  the  requisite  air-supply  are  not  forthcoming  :  the  aquatic 
pupa  breathes  by  three  large  abdominal  spiracles  like  Paraponyx. 

Musotimidae1  is  a  small  group  of  two  or  three  genera  found  in 
Australia  and  Polynesia  ;  and  the  Tiueodidae  also  consist  of  only 
two  Australian  genera.  Siculodidae  is  likewise  a  small  Antarctic 
group,  placed  by  Meyrick  in  Pyralidina  ;  but  his  view  is  not 
accepted  by  Snellen  and  Bagonot.  Epipaschiinae  (fornierly 
tivated  as  a  separate  family)  and  Endotrichiinae  are,  according 
to  Meyrick,  subdivisions  of  the  family  Pyralidae  proper,  an 
enormous  group  of  more  than  100  genera,  The  Chrysauginae 
consist  chiefly  of  American  forms,  and  have  not  been  treated  by 
Meyrick  ;  some  of  this  group  have  been  classed  with  Tortricid.u- 
or  Deltoidae  on  account  of  the  undulating  costa  of  the  front  wings 
and  the  long,  peculiar  palpi.  The  Galleriidae  are  a  small  group 
including  Insects  that  live  in  bees'-nests,  and  feed  on  the  wax 

1  For  Bibliographic  references  connected  Avith  the  divisions  of  Pyralidae    see 
Ragouot,  Ann.  Soc.  ent.  France  (6),  x.  1890,  pp.  458,  rt<-. 


424  LEPIDOPTERA  CHAP. 

etc. ;  others  eat  seeds,  or  dried  vegetable  substances.  Three 
out  of  our  five  British  species  of  this  family  occur  (usually 
gregariously)  in  bee  -  hives,  and  have  the  peculiar  habit 
of  spinning  their  cocoons  together.  The  mass  of  common 
cocoons  formed  in  this  manner  by  Aphomia  sociella  is  remark- 
ably tough  and  enduring ;  portions  of  it  are  not  infrequently 
picked  up,  and  as  the  cocoons  are  of  a  peculiar  tubular  form 
their  nature  gives  rise  to  some  perplexity. 

Phycitidae  :  is  another  very  large  assemblage  of  Insects  with 
very  diverse  habits.  The  frenulum  and  retinaculum  are  similarly 
formed  in  the  two  sexes  :  the  males  frequently  have  the  basal-joint 
of  the  antennae  swollen  ;  hence  the  term  "  Knot-horns  "  applied 
by  collectors  to  these  moths.  The  larvae  of  the  species  of 
Epliestia  infest  groceries,  and  most  children  have  become  to  a  slight 
extent  acquainted  with  them  amongst  dried  figs ;  that  of  E. 
kuelmiella  has  become  very  injurious  in  flour-mills,  its  enormous 
increase  being  due  in  all  probability,  to  the  fact  that  the  favour- 
able and  equable  temperature  maintained  in  the  mills  promotes  a 
rapid  succession  of  generations,  so  that  the  Insect  may  increase 
to  such  an  extent  as  to  entirely  block  the  machinery.  Many  of 
the  Phycitidae  feed  on  the  bark  of  trees  in  galleries  or  tunnels 
constructed  partially  of  silk.  A  very  peculiar  modification  of 
this  habit  in  Cecidipta  excoecaria  has  been  described  by  Berg.  ~ 
In  Argentina  this  Insect  takes  possession  of  the  galls  formed  by 
a  Chermes  011  Excoecaria  Inglandulosa,  a  Euphorbiaceous  tree. 
The  female  moth  lays  an  egg  on  a  gall,  and  the  resulting  larva 
bores  into  the  gall  and  nourishes  itself  on  the  interior  till  all  is 
eaten  except  a  thin  external  coat ;  the  caterpillar  then  pupates 
in  this  chamber.  The  galls  vary  in  size  and  shape,  and  the 
larva  displays  much  constructive  ability  in  adapting  its  home  to 
its  needs  by  the  addition  of  tubes  of  silk  or  by  other  modes.  Some- 
times the  amount  of  food  furnished  by  the  interior  of  the  gall  is 
not  sufficient ;  the  larva,  in  such  cases,  resorts  to  the  leaves  of  the 
plant  for  a  supplement,  but  does  not  eat  them  in  the  usual 
manner  of  a  caterpillar;  it  cuts  off  and  carries  a  leaf  to  the 
entrance  of  its  abode,  fastens  the  leaf  there  with  silk,  and  then 
itself  entering,  feeds,  from  the  interior,  on  the  food  it  lias  thus 
acquired.  Another  Phycitid,  Dakruma  coccidivora,  is  very 

1  Monograph,  by  Ragonot,  in  Romanoff,  Mem.  Lep.  vii.  1893. 

-  J-:,if.  Z.it.  X/.///V,  1.X7S,  p.  2:50. 


vi  HETEROCERA — PYRALIDAE  425 

beneficial  in  North  America  by  eating  large  Scale-Insects  of  the 
Lecanium  group,  somewhat  after  the  fashion  of  Erastria  scit-ida  ;  it 
does  not  construct  a  case,  but  shelters  itself  when  walking  from 
one  scale  to  another  by  means  of  silken  tubes ;  it  suffers  from, 
the  attacks  of  parasites.1  Oxychirotinae,  an  Australian  group, 
is  interesting  because,  according  to  Meyrick,  it  possesses  forms 
connecting  the  Pterophoridae  with  the  more  normal  Pyralids. 

Crambidae,  or  Grass-moths,  are  amongst  the  most  abundant 
Lepidoptera  in  this  country,  as  they  include  the  little  pale  moths 
that  fly  for  short  distances  amongst  the  grass  of  lawns  and 
pastures  ;  they  fold  their  wings  tightly  to  their  body,  and 
have  a  head  pointed  in  front,  in  consequence  of  the  form 
and  direction  of  the  palpi.  They  sit  in  an  upright  position 
on  the  stems  of  grass,  and  it  has  been  said  that  this  is  done 
because  then  they  are  not  conspicuous.  Perhaps :  but  it  would  be 
a  somewhat  difficult  acrobatic  performance  to  sit  with  six  legs 
across  a  stem  of  grass.  The  larvae  are  feeders  011  grass,  and 
construct  silken  tunnels  about  the  roots  at  or  near  the  surface. 
The  Ancylolominae  are  included  in  Crambidae  by  Meyrick  and 
Hampson.  Schoenobiinae2  are  included  by  Meyrick  in  Pyraustidae, 
but  this  view  appears  not  to  meet  with  acceptance,  and  the  group 
is  more  usually  associated  with  the  Crambidae.  Most  writers 
place  the  anomalous  genus  Acentropus  as  a  separate  tribe,  but  it 
is  associated  by  both  Meyrick  and  Hampson  with  Schoenobius. 
This  Insect  is  apparently  the  most  completely  aquatic  of  all  the 
Lepidoptera,  and  was  for  long  associated  with  the  Trichoptera 
in  consequence  of  its  habits  and  of  the  scaling  of  the  wings 
being  of  a  very  inferior  kind.  The  males  may  sometimes  be 
found  in  large  numbers  fluttering  over  the  surface  of  shallow,  but 
large,  bodies  of  water  ;  the  females  are  rarely  seen,  and  in  some 
cases  have  no  wings,  or  have  these  organs  so  small  as  to  be  useless. 
The  female,  it  would  appear,  comes  quite  to  the  surface  for 
coupling,  and  then  takes  the  male  beneath  the  water.  The  larvae 
have  the  usual  number  of  Lepidopterous  feet,  and  apparently  feed 
on  the  leaves  of  plants  below  water  just  as  Lepidopterous  larvae 
ordinarily  do  in  the  air. 3  They  have  no  trace  of  gills,  and  their 

1  Howard,  Insect  Life,  vii.  1895,  p.  402. 

2  Monograph  by  Hampson,  P.  Zool.  Soc.  London,  1895,  p.  897-974. 

y  Discjue,  Eat.  Zeit.  Stettin,  li.  1890,  p.  59.     Cf.  also  Rebel,  Zool.  Jahrl.  Syst. 
xii.  1898,  p.  3. 


426  LEPIDOPTERA  CHAP. 

mode  of  respiration  is  unknown.  A  great  deal  has  Leen  written 
about  these  Insects,  but  really  very  little  is  known.  They  are 
abundant,  though  local  in  many  parts  of  North  and  Central 
Europe  ;  some  of  the  females  have,  as  we  have  said,  abbreviated 
wings,  but  how  many  species  there  are,  and  whether  the  modifica- 
tions existing  in  the  development  of  the  wings  are  constant  in 
one  species  or  locality,  are  unknown  as  yet. 

Fam.  42.  Pterophoridae  :  (Plume-moths'). — Elegant  Insects 
of  small  size,  usually  with  the  wings  divided  (after  the  fashion  of 
a  hand  into  fingers)  so  as  to  form  feathers :  the  extent  of  this 
division  is  diverse,  but  the  hind  wings  are  more  completely  divided 
than  the  front,  which  indeed  are  sometimes  almost  entire.  The 
group  is  placed  by  Meyrick  in  his  Pyralidina,  but  there  are  many 
entomologists  who  look  on  it  as  distinct.  It  consists  of  two 
sub  -  families,  Agdistinae  and  Pterophorinae,  that  have  been 
treated  as  families  by  many  entomologists.  The  Agdistiuae 
(of  which  we  have  a  British  representative  of  the  only  genus 
Aydistes)  have  the  wings  undivided.  Pterophorinae  have  the 
hind  wings  trifid  or  (rarely)  cp:iadrifid,  the  front  wings  bifid  or 
(rarely)  trifid.  The  larvae  of  the  Pterophorinae  are  different 
from  those  of  Pyralidae,  being  slow  in  movement  and  of  heavy 
form,  covered  with  hair  and  living  exposed  on  leaves ;  the  pupae 
are  highly  remarkable,  being  soft,  coloured  somewhat  like  the 
larvae,  and  also  hairy  like  the  larvae,  and  are  attached  somewhat 
after  the  manner  of  butterfly- pupae  by  the  cremaster :  but 
in  some  cases  there  is  a  slight  cocoon.  There  is,  however, 
much  variety  in  the  larval  and  pupal  habits  of  the  Ptero- 
phoridae, many  having  habits  of  concealment  of  divers  kinds. 
We  have  thirty  species  of  these  lovely  Plume-moths  in  Britain. 
The  family  is  widely  distributed,  and  will  probably  prove 
numerous  in  species  when  the  small  and  delicate  Insects  existing 
in  the  tropics  are  more  appreciated  by  collectors. 

Fam.  43.  Alucitidae  (Orneodidae  of  Meyrick  and  others).— 
The  genus  Alucita  includes  the  only  moths  that  have  the  front 
and  hind  wings  divided  each  into  six  feathers.  Species  of  it, 
though  not  numerous,  occur  in  various  regions.  The  larva  and 
pupa  arc  less  anomalous  than  those  of  the  Pterophoridae,  though 
the  imago  is  more  anomalous.  Tbe  caterpillar  of  our  British  A. 
polydactyla  feeds  on  the  flower-buds  of  honey-suckle,  and  forms  a 

1  Classification;  Mt-yriek,  Tr.  nit.  Sue.  London,  1886,  p.  1. 


vi  HETEROCERA TORTRICIDAE  427 

cocoon.  The  moth  with  wings  expanded  is  about  an  inch  across, 
and  is  a,  lovely  object.  It  is  not  rare,  though  seldom  numerous. 

Fam.  44.  Tortricidae. — Moths  of  small  size,  with  a  rather 
ample  wing  area,  with  the  wing-fringes  never  as  long  as  the 
wings  are  wide  (long  across),  the  hind  wings  without  a  pattern  : 
the  anterior  nervure  on  the  hind  wings  is  simply  divergent  from 
that  next  to  it,  and  the  internal  nervure,  Ib,  is  very  evidently 
forked  at  the  base.  The  larvae  inhabit  their  food,  which  may  be 
rolled  up  or  twisted  leaves,  or  the  interior  of  fruits  and  herbs,  or 
galls,  or  even  roots ;  they  exhibit  less  diversity  than  is  usual  in 
other  large  series  of  moths  ;  all  have  the  normal  complement  of 
sixteen  legs.  This  group  is  a  very  extensive  one,  but  is  much 
neglected  owing  to  the  great  difficulties  attending  its  study ; 
it  is  not  recognised  in  Hampson's  Table  of  families  given  on 
p.  370,  being  there  merged  in  Tiueidae.  It  appears,  however, 
to  be  a  really  natural  group,  and  it  is  not  desirable  to  merge  it 
in  the  sufficiently  enormous  assemblage  of  the  Tineidae  till 
this  has  been  shown  to  be  necessary  by  the  light  of  a  greater 
knowledge  of  the  external  anatomy  than  we  possess  at  present. 
The  term  Microlepidoptera  is  frequently  met  with  in  entomo- 
logical literature,  and  should,  we  think,  be  confined  to  the  two 
series  Tortricidae  and  Tineidae.  The  Pterophoridae,  and  even 
the  I'yralidae,  have  been,  and  still  sometimes  are,  included  under 
this  term,  but  at  present  it  seems  best  to  limit  its  application  as 
is  here  suggested. 

Three  great  divisions  are  at  present  recognised ;  these  were 
formerly  called  by  Meyrick,1  Tortricidae,  Grapholithidae,  Conchy- 
lidae ;  subsequently/  he  has  adopted  the  names  Tortricidae, 
Epiblemidae,  1'haloniadae.  Lord  Walsingham,  who  has  devoted 
a  great  deal  of  time  and  study  to  the  elucidation  of  this  most 
difficult  group,  has  suggested 3  that  another  change  is  desirable, 
and  if  so  the  nomenclature  will  be : — 1.  Tortricidae  [or  Tor- 
ticinae,  according  to  the  view  that  may  be  taken  as  to  the  group 
being  family  or  sub-family]  ;  2.  Phaloniidae  [  =  the  formerly 
used  name,  Conchylidae] ;  3.  Olethreutidae  [  —  the  formerly  used 
name  Grapholithinae  =  Epiblemidae,  Meyr.].  AYe  have  upwards 
of  300  species  in  Britain,  nearly  200  of  which  belong  to  the 
last  division.  The  name  Tortricidae  refers  to  the  habit  the 

1  P.  Linn.  Soc.  X.  S.   Wales  (2),  vi.  18S1,  p.  410. 
-  Handbook  Brit.  Ley.  1895,  p.  493.  y   Tr.  cut.  Soc.  London,  1895,  p.  495. 


428  LEPIDOPTERA  CHAP. 


larvae  of  these  moths  possess  of  rolling  up  leaves,  or  twisting 
and  distorting  shoots  and  buds. 

The  mode  in  which  leaves  and  shoots  are  twisted  and  rolled 
by  the  very  small  larvae  has  been  much  discussed  and  is  pro- 
bably the  result  of  two  or  three  distinct  causes:--!,  the 
immediate  operations  of  the  larva  ;  2,  the  contraction  of  silk 
when  drying  ;  3,  changes  in  the  mode  of  growth  of  the  parts  of 
the  vegetable,  resulting  from  the  interference  of  the  caterpillar. 
The  larvae  of  this  family  that  live  in  fruits  are  only  too  widely 
(we  will  not  say  well)  known.  Stainton  gives  as  the  habitat  of 
Epinotia  fitncbrana,  "  larva  frequent  in  plum-pies  "  ;  the  cater- 
pillar of  Carpocapsa  pomondla  (the  Codling -moth)  mines  in 
apples  and  pears,  and  its  ravages  are  known  only  too  well  in 
widely  distant  parts  of  the  world  where  fruit-trees  of  this  kind 
are  cultivated.  C.  splendana  lives  in  acorns  and  walnuts  ;  C. 
jti.li.niM  in  Spanish  chestnuts.  Two,  if  not  more,  larvae  live  in 
the  seeds  of  Euphorbiaceous  plants,  and  have  become  notorious 
under  the  name  of  jumpiug-beans,  on  account  of  the  movements 
they  cause.  As  these  latter  show  no  trace  externally  of  being 
inhabited,  the  movements  are  supposed  to  be  a  mysterious  pro- 
perty of  the  seed ;  they  are  really  due  to  its  containing  a  large 
cavity,  extending,  in  one  direction  of  the  seed,  nearly  or  quite 
In  >m  skin  to  skin  ;  in  this  the  larva  makes  a  movement  sufficient 
to  alter  the  point  of  ecjuilibrium  of  the  quiescent  seed,  or  as 
a  free  body  to  strike  some  part  of  it.  The  exact  nature  of  the 
movements  of  the  larva  have  not,  we  believe,  been  ascertained. 
There  are,  at  least,  two  species  of  these  Insects,  and  two  plants 
harbouring  them,  known  in  the  United  States  and  Mexico,  viz. 
Cwrpoccipsa  saltitans  living  in  the  seeds  of  Croton  colliguaja  and 
Grapliolitlia  sebudianii.i.e  living  in  the  seeds  of  Sebastiania 
bicapsidaris. 

Fam.  45.  Tineidae.  —  Small  moths  with  the  labial  palpi 
more  flexible  and  mobile  than  in  other  moths ;  usually  separated 
and  pointed.  Hind  wings  frequently  with  very  long  fringes,  the 
wing  itself  being  proportionally  reduced  in  size,  and  in  con- 
sequence pointed  at  the  tip.  Larvae  very  diverse,  almost  always 
with  habits  of  concealment.  The  series  of  forms  included  under 
this  hr.nl  is  very  numerous,  the  British  species  alone  mounting 
up  to  700,  while  the  total  described  cannot  be  less  than  4000. 
This  number,  however,  must  be  but  a  fragment  of  what  exists, 


vi  HETEROCERA TIXEIDAE  429 

ii'   Mr.   Meyrick    be    correct   in   supposing   that  a   single   one   of 
the    divisions   of   the    family — Oecophoridae — comprises    2000 
species    in    Australia    and    Xew    Zealand   alone.      As   the   study 
of    these    Insects    is    attended 
with     great     difficulty    on     ac- 
count   of    their     fragility    and 
the    minute    size    of   the    great 
majority,    it    is    not    a    matter 

for  surprise  that  their  classiti- 

4%'     yt&M 

cation    is    in    a    comparatively  *^~^T^  +^T 

rudimentary    state.      AVe    shall 

not,  therefore,  deal  with  it  here. 

^^    .  .         FIG. '207. — Diplosaralignivora(Gelecbiides). 

Neither  can  we  attempt  to  give  Hawaiian  islands. 

any  idea  of  the  extreme  diversity 

in  the  colours,  forms,  and  attitudes  of  these  small  Insects.  The 
one  shown  in  Pig.  207,  is  remarkable  on  account  of  the  great 
accumulation  of  scales  on  the  wings  and  legs.  As  regards  the 
pointed  wings  and  the  long  fringes,  we  may  remark  that  it  is 
probable  that  in  many  of  these  small  forms  the  wings  are 
passive  agents  in  locomotion ;  a  similar  condition  of  the  wings 
is  found  in  other  very  minute  Insects,  e.g.  Thysauoptera  and 
Trichopterygidae  ;  in  all  these  cases  the  framework  of  the  wings  is 
nearly  absent :  in  some  forms  of  the  Tineidae,  Opostega,  e.g.  the 
nervules  are  reduced  to  three  or  four  in  each  wing.  The 
variety  in  habits  is  as  great  as  that  of  the  external  form,  and 
the  larvae  exceed  in  diversity  those  of  any  other  group  of 
Lepidoptera.  Xo  doubt  a  corresponding  amount  of  diversity 
will  be  discovered  in  the  details  of  structure  of  the  perfect 
Insects,  the  anatomy  of  but  few  having  been  at  present  investi- 
gated. Tinea  pellionella  has  two  very  important  peculiarities  in 
its  internal  anatomy :  the  testes  consist  of  four  round  follicles 

u 

on  each  side,  and,  contrary  to  the  condition  generally  prevalent 
in  Lepidoptera,  are  not  brought  together  in  a  common  capsule  :  the 
two  groups  are,  however,  not  <|iiite  free  (as  they  are  in  Hfpialv.s), 
but  are  connected  by  a  loose  tracheal  network.  Even  more 
remarkable  is  the  fact  also  pointed  out  by  Cholodkovsky '  that 
the  adult  Insect  possesses  only  two  Malpighian  tubes  instead  of 
six,  the  normal  number  in  Lepidoptera;  in  the  larva  there  are, 
however,  six  elongate  tubes.  The  group  of  forms  to  which 

1  Zool.  ^><c.  v.  1882.  p.  262. 


430  LEPIDOPTERA  CHAP. 

Tinea  belongs  is  remarkable  for  the  diversity  and  exceptional 
character  of  the  food -habits  of  the  larvae ;  species  subsist 
on  dried  camel's  dung,  various  kinds  of  clothes,  furs,  and 
hair,  and  even  about  horns  of  deer  and  horses'  hoofs :  one 
species  has  been  found  in  abundance  in  the  hair  of  a  live 
sloth,  Braili/piis  cuculliger,  under  circumstances  that  render  it 
possible  that  the  larva  feeds  on  the  creature's  hair,  though  it 
may  feed  on  minute  vegetable  matter  found  in  the  hair. 
The  larva  of  Tinea  vastella  is  occasionally  found  feeding  on  the 
horns  of  living  antelopes.  Several  species  of  Tineidae  are  known 
to  devour  Scale-Insects. 

Lita  solanella  is  notorious  for  the  ravages  it  commits  on 
stored  potatoes.  Quite  a  number  of  species  live  on  cryptogamic 
matter,  or  in  old  wood  ;  Oinophila  v-flavum  feeds  on  the  mould 
on  the  walls  of  cellars,  and  is  reputed  to  be  injurious  by  occasion- 
ally also  attacking  the  corks  of  bottles  containing  wine.  Oecocecis 
yuyonella  is  said  to  be  the  cause  of  galls  on  Limoniastrum 
guyonianum,  a  plant  that,  growing  in  the  deserts  to  the  south 
of  Algeria,  is  a  favourite  food  of  camels,  and  is  frequently  entirely 
covered  with  sand.  The  deposition  of  an  egg  by  this  moth  is 
believed  by  Gue"nee  l  to  give  rise  to  a  gall  in  which  the  larva  is 
entirely  enclosed  (like  the  larvae  of  the  gall-flies).  Of  Clothes- 
moths  there  are  at  least  three  species  widely  distributed. 
Trichopliaya,  tapctzdla  is  perhaps  entitled  to  be  considered  the 
Clothes-moth  ;  its  caterpillar  not  only  feeds  on  clothes,  but  spins 
webs  and  galleries  amongst  them.  Tinea  pellionella  is  also  very 
common  ;  its  larva  lives  in  a  portable  case,  while  that  of  the 
third  species,  Tineola  biselliella,  forms  neither  a  case  nor  definite 
galleries.  We  have  found  this  the  most  destructive  of  the  three 
at  Cambridge'.  Clothes  or  valuable  furs  may  be  completely  pro- 
tected by  wrapping  them  in  good  sound  paper  in  such  a  way 
that  no  crevices  are  left  at  the  places  where  the  edges  of  the 
paper  meet.  Garments  that  have  become  infested  may  be  entirely 
cleared  by  free  exposure  to  air  and  sunshine. 

Two  species  of  Tinea  have  been  recorded  as  viviparous,  viz. 
Tinea  vim-para  in  Australia,  and  an  undetermined  species  in 
Smith  Ann-ricii.  The  species  of  the  genus  Sulcnobia — in  which 
the  female  is  apterous — are  frequently  parthenogenetic.  The 
group  Taleporiidae,  to  which  this  genus  belongs,  is  by  some 

1  Ann.  Soc.  ent.  France  (4),  x.  1870,  p.  1,  pi.  vii. 


vi  HETEROCERA TINEIDAE  431 

classified   with   Psychidae,  in   which   family,  as  we   have  pointed 
out,  one  or  two  parthenogenetic  forms  are  also  known. 

The  larvae  of  Tineidae,  though  they  do  not  exhibit  the 
remarkable  armature  found  in  so  many  of  the  larger  caterpillars, 
are  exceedingly  diverse.1  Some  are  entirely  destitute  of  feet 
(Phyllocnistis).  Others  are  destitute  of  the  thoracic  legs ; 
Nepticula  is  in  this  case,  but  it  is  provided  with  an  increased 
number  of  abdominal  feet,  in  the  form  of  more  or  less  imperfect 
ventral  processes.  Some  mine  in  leaves,  others  live  in  portable 
cases  of  various  forms.  Some  are  leaf-miners  during  their 
early  life,  and  subsequently  change  their  habits  by  con- 
structing a  portable  case.  The  genus  Coleopliora  affords 
numerous  instances  of  this  mode  of  life ;  the  habits  of  these 
case-bearers  exhibit  considerable  variety,  and  there  are  many 
points  of  interest  in  their  life-histories.  Change  of  habit  during 
the  larval  life  has  already  been  alluded  to  as  occurring  in  many 
Lepidoptera  and  is  nowhere  more  strikingly  exemplified  than  in 
certain  Tineidae.  Meyrick  mentions  the  following  case  as 
occurring  in  an  Australian  Insect,  Nematobola  orthotricha ; 2  the 
larva,  until  two-thirds  grown,  is  without  feet,  and  is  almost 
colourless,  and  mines  in  the  leaves  of  Persoonia  lanceolata ;  but 
when  two-thirds  grown  it  acquires  sixteen  feet,  changes  colour, 
becoming  very  variegate,  and  feeds  externally,  unprotected,  on  the 
leaves.  The  cases  of  the  case-bearing  Tineids  are  usually  of 
small  size,  and  do  not  attract  attention  like  those  of  Psychidae. 
A  very  remarkable  one  was  discovered  by  Mr.  E.  E.  Green  in 
Ceylon,  and  was  at  first  believed  to  be  formed  by  a  Caddis-worm. 
It  has  now  been  ascertained  that  the  Insect  forming  it  is  the 
caterpillar  of  Pseudodoxia  limulus,  a  Tineid  moth  of  the  group 
Depressariidae ; 3  the  case  is  composed  of  minute  fragments  of 
moss,  sand,  and  lichens  ;  the  anterior  end  is  dilated  into  a  shield- 
like  hood  that  covers  and  protects  the  anterior  parts  of  the 
larva  when  feeding ;  the  food  is  mosses  and  lichens  on  rocks  and 
trees.  Before  pupating,  the  larva  folds  clown  the  edges  of  the 
hood  over  the  mouth  of  the  tube,  like  an  envelope,  fastening 
them  witli  silk.  The  case  is  fixed  to  the  rock  or  other  support 
and  hangs  there  until  the  moth  appears. 

1  For  table  of  the  larvae,  according  to  number  of  feet  and  other  characters,  see 
Sorhagen,  Berlin,  ent.  Zeit.  xxvii.  1883,  pp.  1-S. 

2  P.  Linn.  Soc.  N.S.   Wales  (2)  vii.  1892,  p.  593. 

3  Durraut,  Ent.  May.,  xxxi.  1895,  p.  107. 


432 


LEPIDOPTERA 


CHAP. 


The  family  Frodoxidae  consists  of  some  Tineids,  the  larvae  of 
which  feed  in  the  pods  and  stems  of  the  Yuccas  of  south-western 
North  America ;  they  have  the  mouth  of  very  unusual  form 

(Fig.  208,  E),  and 
some  of  them,  by 
aid  of  this  peculiar 
month,  exhibit  a 
remarkable  modifi- 
cation of  instinct. 
The  facts  are  chiefly 
known  from  the 
observations  of 
Eiley  1  on  Pro-nulm 
yuccasella,  a  moth 
living  on  Yucca 
filamentosa ;  this 
plant  has  been  in- 
troduced into  our 
gardens  in  this 
country,  where  it 
never,  we  believe, 
produces  seed.  The 
Yuccas  are  not 
fitted  for  self-fertil- 
isation or  for  fer- 
tilisation by  Insect 
agency  of  an.  ordi- 
nary kind.  The 
progeny  of  the 
moth  develops  in 
the  pods  of  the 
plant,  and  as  these 
cannot  grow  until 
the  flowers  have 
been  fertilised,  the  moth  has  the  habit  of  fertilising  the  flowers 
at  the  time  she  lays  her  egg  in  the  part  that  is  to  develop  into 
the  pod,  and  to  be  the  food  for  her  own  progeny.  The  female 
inoth  first  visits  the  stamens,  and  collects,  bv  the  aid  of  the 


FIG.  208. — Pronuba  .tynthefim.  North  America.  A,  Larva  : 
B,  C,  pupa,  ventral  and  lateral  aspects  ;  D,  female  moth  ; 
E,  head  and  part  of  thorax  of  the  female  moth  :  a, 
labial  palp  ;  b,  maxillary  tentacle  ;  c,  maxillary  palp  ; 
d,  proboscis  ;  e,  base  of  trout  leg.  (After  Riley.) 


1  "The  Yucca  moth  and  Yucca  Pollination,"  Hep.  Missouri  Botanical  Garden, 
1892,  pp.  99-158. 


vi  HETEROCERA PRODOXIDAE — -ERIOCEPHALIDAE        433 

maxillae  (which  in  this  sex  are  very  remarkably  formed),1  a  con- 
siderable mass  of  pollen,  which  she  holds  by  means  of  the  peculiar 
maxillary  tentacles  ;  she  then  lays  an  egg  in  the  pistil,  usually 
of  some  flower  other  than  that  from  which  she  has  gathered  the 
pollen ;  and  after  she  has  accomplished  this  act  she  carefully 
applies  the  pollen  she  had  previously  collected  to  the  pistil,  so 
as  to  secure  the  fertilisation  of  the  flower  and  the  development 
of  the  pod. 

The  species  of  Prodoxus  stand  in  a  very  peculiar  relation 
to  Pronuba.  They  also  live  in  Yuccas,  and  have  habits  similar 
to  those  of  Pronuba,  with  the  important  exception  that,  being 
destitute  of  the  requisite  apparatus,  they  do  not  fertilise 
the  Yucca-flowers,  and  are  thus  dependent  on  Pronuba  for 
the  steps  being  taken  that  are  necessary  for  the  rearing  of  the 
progeny  of  the  two  kinds  of  moth.  Hence  the  name  of  Yucca- 
moth  has  been  bestowed  on  Pronuba,  and  that  of  "  bogus  Yucca- 
moth  "  on  the  Prodoxus.  The  Pronuba  wre  figure  is  the  largest 

O  '      O 

and  most  remarkable  species  of  the  genus  and  fertilises  Yucca 
brevifolia ;  the  larva  is  destitute  of  abdominal  feet,  and  in 
the  pupa  the  spines  on  the  back  that  exist  in  nearly  all  pupae 
that  live  in  stems  are  developed  to  an  extraordinary  extent. 
The  Yuccas  do  not  flower  every  year,  and  the  Prodoxidae  have  a 
corresponding  uncertainty  as  to  their  periods  of  appearance, 
passing  sometimes  a  year  or  two  longer  than  usual  in  the  pupal 
stage. 

Fam.  46.  Eriocephalidae. — This  family  has  recently  been 
proposed  for  some  of  the  moths  formerly  included  in  the  genus 
Micropteryx.'2  They  are  small,  brilliant,  metallic  Insects,  of 
diurnal  habits,  but  are  very  rarely  seen  on  the  wing,  and  it  is 
doubtful  whether  they  can  fly  much.  These  little  Insects  are  of 
peculiar  interest,  inasmuch  as  they  differ  from  the  great  majority 
of  the  Lepidoptera  in  at  least  two  very  important  points,  viz. 
the  structure  of  the  wings  and  of  the  mouth-parts.  The  mouth 
shows  that  we  may  consider  that  the  Lepidoptera  belong  to  the 
mandibulate  Insects,  although  in  the  great  majority  of  them  the 
mandibles  in  the  final  instar  are  insignificant,  functionless 
structures,  or  are  entirely  absent,  and  although  the  maxillae  are 
t 

1  The  maxillary  tentacle  is  considered  by  Prof.  J.  B.  Smith  to  be  a  prolongation 
of  the  stipes,  cf.  antea,  p.  309  ;  also  Insect  Life,  v.  1893,  p.  161. 

2  Chapman,  Tr.  cut.  Soc.  London,  1894,  p.  366. 

VOL.   VI  2   F 


434 


LEPIUOPTERA 


CHAP. 


so  highly  adapted  for  the  tasting  of  sweets  that  it  is  difficult  to 
recognise  in  them  the  parts  usually  found  in  the  maxilla  of 
inandibulate  Insects.  Eriocepliala  in  both  these  respects  connects 
the  Lepidoptera  with  Mandibulata :  the  mandibles  have  been 
shown  by  Walter1  to  be  fairly  well  developed  ;  and  the  maxillae  are 
not  developed  into  a  proboscis,  but  have  each  two  separate,  differen- 
tiated— not  elongated — lobes,  and  an  elongate,  five-jointed,  very 
flexible  palpus.  The  moths  feed  on  pollen,  and  use  their 
maxillae  for  the  purpose,  somewhat  in  the  style  we  have  men- 
tioned in  Prodoxidae.  The  wings  have  no  frenulum,  neither 
have  they  any  shoulder,  and  they  probably  function  as  separate 
organs  instead  of  as  a  united  pair  on  each  side  :  the  modification 
of  the  anterior  parts  of  the  hind  wing — whereby  this  wing  is 
reduced  as  a  flying  agent  to  the  condition  of  a  subordinate  to  the 
front  wing — does  not  here  exist :  the  hind  wing  differs  little  from 
the  front  wing  in  consequence  of  the  parts  in  front  of  the  cell  being 
well  developed.  There  is  a  small  jugum.  These  characters  have 
led  Packard  to  suggest  that  the  Eriocephalidae  should  be  separated 
from  all  other  Lepidoptera  to  form  a  distinct  sub-Order,  Lepidoptera 
Laciniata.2  The  wing-characters  of  Eriocepliala  are  repeated — as 
to  their  main  features — in  Hepialidae  and  Micropterygidae ;  but 
both  these  groups  differ  from  Eriocepliala  as  to  the  structure  of 
the  mouth-parts,  and  in  their  metamorphoses.  Although  Erio- 
<'>'l>!i<i]<i,  caltJiella  is  one  of  our 
most  abundant  moths,  occur- 
ring in  the  spring  nearly  every- 
where, and  being  easily  found 
on  account  of  its  habit  of  sit- 
ting in  buttercup-flowers,  y«'t 
its  metamorphoses  were  till 
recently  completely  unknown. 
Dr.  Chapman  has,  however, 

been     able     to     give     US    some    FlG-    209.— Larva   of  Eriocephala    calthella. 

(After  Chapman.)     A,  Young  larva  from 
information    as    to    the    habits          side,   x  50  ;  B,  portion  of  skin  with  a  bulla 

and  Structure  of  the  larvae,  111  orf  ^all-like  appendage  :  ,,  abdominal  foot 

of  larva. 

both  of  which  points  the  crea- 

The  eggs  and  young  larvae  are  "  quite 


ture  is  most  interesting. 


1  Walter,  Jena.  ZcHs,-l<r.  Xatunv.  xviii.   1885.     He  did  not  distinguish  Erio- 
lilinln  as  a  ^riiiis,  ,-is  \\-i-  have  explained  <>n  ]>.  308. 

2  Amer.  \<//nml.  xxix.  1895,  pp.  636  and  803. 


VI 


ERIOCEPHALIDAE — MICROPTERYGIDAE 


435 


unlike  our  ideas  of  a  Lepidopterous  Insect  ; "  the  former  have  a 
snowy  or  mealy  appearance,  owkig  to  a  close  coating  of  minute 
rods  standing  vertically  on  the  surface  of  the  egg,  and  often 
tipped  with  a  small  bulb.  The  larva  lives  amongst  wet  moss 
and  feeds  on  the  growing  parts  thereof;  it  is  not  very  similar  to 
any  other  Lepidopterous  larva :  Dr.  Chapman  suggests  a  simi- 
larity to  the  Slug-worms  (Linmcodids),  but  Dyar  is  probably 
correct  in  thinking  the  resemblances  between  the  two  are  unim- 
portant :  the  larva  of  Eriocephala  possesses  three  pairs  of  thoracic 
legs,  and  eight  pairs  of  abdominal  appendages,  placed  on  the 
segments  immediately  following  the  thorax  ;  on  the  under-surface 
of  the  ninth  and  tenth  abdominal  segments  there  is  a  sucker, 
trifoliate  in  form  ;  this  is  probably  really  situate  entirely  on  the 
tenth  segment :  the  body  bears  rows  of  ball-appendages,  and  the 
integument  is  beautifully  sculptured.  The  head  is  retractile 
and  the  antennae  are  longer  than  is  usual  in  caterpillars.  This 
larva  is  profoundly  different  from  other  Lepidopterous  larvae 
inasmuch  as  the  abdominal  feet,  or  appendages,  are  placed  on 
different  segments  to  what  is  customary,  and  are  of  a  different 
form.  Unfortunately  the  pupa  has  not  been  procured,  but  there 
is  some  reason  for  supposing  that 
it  will  prove  to  be  more  like  that  of 
Tineidae  than  like  that  of  Microp- 
terygidae. 

The  New  Zealand  genus  Palaeo- 
micra  is  only  imperfectly  known. 
Meyrick  considers  it  the  "  most 
ancient "  Lepidopteron  yet  dis- 
covered ;  and  it  would  appear  that 
its  relations  are  with  EriocepJidla 
rather  than  with  Micropteryx.  From 
information  he  has  kindly  given  to 
us,  we  are  able  to  say  that  this  moth 

possesses  mandibles  but  no  proboscis. 

FIG.  210. 

Fam.    47.    Micropterygldae.- 

Small    moths    of    metallic    colours, 

without    mandibles,    with    elongate 

maxillary  palpi :  without  frenulum  :  both  wings  with  a  complex 

system  of  wing-veins :   on  the  hind  wings   the  area  anterior  to 

the  cell  is  large,  and  traversed  by  three  or  four  elongate,  parallel 


B 


Larva  of  Micropteryx  sp. 
A,  Ventral  view  of  the  larva, 
magnified  ;  B,  the  same,  with 
setae  unduly  magnified.  Britain. 


436 


LEPIDOPTERA 


CHAP. 


veins.  There  are  110  mandibles,  but  there  is  a  short,  imperfect 
proboscis.  Larva  (Fig.  210)  without  any  legs,  mining  in  leaves. 
The  pupa  (Fig.  211)  is  not  a  pupa  obtecta,  but  has  the  head 
and  appendages  free,  and  it  provided  with  enormous  mandibles. 
Although  these  Insects  in  general  appearance  resemble  Erio- 
cephala  to  such  an  extent  that  both  have  been  placed  in  one 
genus,  viz.  Micropteryx,  yet  the  two  forms  are  radically  distinct. 

The    most    remarkable 

\  / 

point  in  Micropteryx 
is  the  metamorphosis ; 
the  female  moth  is 
furnished  with  a  cut- 
ting ovipositor,  by  the 
aid  of  which  she  de- 
posits an  egg  between 
the  two  layers  of  a 
leaf  after  the  manner 
of  a  saw-fly  ; l  the  larva 
mines  the  newly-opened 
leaves  in  the  early 
spring,  and  feeds  up 
with  rapidity ;  it  by 
some  means  reaches 
the  ground,  and  there 
pupates  in  a  firm  but 
thin  cocoon,  with  grains 
of  earth  fastened  to  it ; 
in  this  it  passes  the 

greater  part  of  its  life 
IIG.  211. — Papa,  of  Micropteryx  (semipurpurella  f).     A,    ' 

Dorsal  aspect  ;  B,  C,  D,  views  of  head  dissected  oft' ;    as  a   larva,  changing  to 
B,    profile;   C,    posterior,   D,    anterior  aspects;    m,    .-,    -,.,  -1^1-^7       nvlv 

-i  .  -i   i  -.-.     •         .  t.1        l_/  LI  I..' 1 1         \  Cl.    y          CCl'l.  AT          J.  J.J. 

mandibles.      Britain.  L  J  J 

the    following     spring. 

The  pupa  is  unlike  any  other  Lepidopterous  pupa,  but  is  similar 
to  those  of  Trichoptera  ;  neither  the  head  nor  the  appendages 
are  glued  to  the  body  or  to  one  another,  but  are  free,  so  that 
the  pupa  can  use  the  appendages  to  a  considerable  extent;  it  is 
furnished  with  enormous  mandibles  (Fig.  211,  C,  D),  which  are 
detached  and  shed  after  emergence.2  In  the  interval  between 

1  Wood,  Ent.  May.  xxvi.  1890,  p.  148. 
-  See  Chapman,  Tr.  cut.  Soc.  London,  1893,  p.  255. 


vi  MICROPTERYGIDAE  437 

the  larval  period  of  feeding  and  the  imaginal  instar,  the  pheno- 
mena of  life  are  essentially  like  those  of  Trichoptera.  The  larva 
has  not  been,  at  all  satisfactorily  studied ;  the  spiracles  appear 
to  be  excessively  minute,  but  have  been  ascertained  by  Dr. 
Chapman  to  be  normal  in  number  and  position. 

All  the  information  we  possess  points  to  profound  distinctions 
between  Micropteryx  and  Eriocepluda,  for  whereas  in  the  former 
the  mandibles  drop  off  from  the  pupa,  so  that  the  imago  has  no 
mandibles,  in  the  latter  the  mandibles  exist,  as  they  do  in 
several  other  true  Lepidoptera.  As  the  history  of  the  mandi- 
bles is  not  known  in  other  Lepidoptera  (where  they  are  present 
in  the  larva  but  wanting  in  the  imago),  it  is  premature  to 
conclude  that  no  other  Lepidoptera  suffer  the  actual  loss  of  the 
mandibles  as  Micropteryx  does,  though  there  is  nothing  to  lead 
us  to  believe  that  in  any  other  Lepidopterous  pupa  are  the 
mandibles  specially  developed  as  they  are  in  Micropteryx.  This 
pupa  is  in  fact  quite  unique  in  this  Order  of  Insects.  When  the 
history  of  the  pupal  mandibles  is  known,  we  shall  be  able  to 
decide  whether  they  are  secondary  structures,  like  the  deciduous, 
supplementary  mandibles  found  in  Otiorhynchides  (Coleoptera, 
Iihynchophora). 


CHAPTER   VII 

DIPTERA OR    FLIES  ;     APHANIPTERA- — OR    FLEAS  ;    THYSAXOPTERA 

—OR    THRIPS 

Order  VII.     Diptera 

Wings  two,  membranous,  usually  transparent  and  never  very  lar;/<  ; 
behind  the  wings  a  pair  of  small  erect  capitate  bodies— 
li  alteres  — frequently  concealed  under  membranous  hoods. 
No  distinct  prothorax,  all  the  divisions  of  the  thorax  being 
united  to  form  a  large  mass.  Mouth-parts  very  variable, 
formed  for  suction  not  for  biting,  frequently  assuming  the 
form  of  a  proboscis  that  can  be  retracted  and  concealed  in  a 
cleft  of  the  under  side  of  the  head.  The  metamorphosis  is 
very  great,  the  larvae  bearing  no  resemblance  whatever  to  the 
perfect  Insects,  but  being  usually  footless  grubs  or  maggots  ; 
frequently  the  head  is  indistinct,  small,  and  retracted. 
Pupa  variable,  either  exposed  and  rather  hard,  with  the 
appendages  of  the  body  more  or  less  adherent ;  or  enclosed 
in  a  scaly  capsule  looking  like  a  seed,  and  when  extracted, 
soft  and  delicate,  with  the  appendages  not  fastened  to  the 
body  incapable  of  movement. 

THIS  definition  of  the  Diptera,  or  two-winged  flies,  is  framed 
without  reference  to  the  fleas,  which  are  wingless,  or  to  a  few 
other  parasitic  wingless  Diptera,  such  as  the  sheep-tick.  Although 
the  Order  is  of  enormous  extent,  these  exceptional  cases  are 
remarkably  few.  About  40,000  species  of  Diptera  have  been 
discovered,  but  these  are  only  a  tithe  of  what  are  still  unknown 
to  science.  The  Order  is  not  a  favourite  one  with  entomologists, 
and  by  the  rest  of  the  world  it  may  be  said  to  be  detested. 
Flies  do  not  display  the  sort  of  intelligence  we  appreciate, 


CHAP.   VII 


DIPTERA    OR    TWO-WINGED    FLIES 


439 


or  the  kind  of  beauty  we  admire,  and  as  a  few  of  the 
creatures  somewhat  annoy  us,  the  whole  Order  is  only  too 
frequently  included  in  the  category  of  nuisances  that  we  must 
submit  to.  Moreover,  the  scavenger-habits  that  are  revealed, 
when  we  begin  to  study  their  lives,  are  very  repugnant  to  many 
persons.  It  is  therefore  no  wonder  that  flies  are  not  popular, 
and  that  few  are  will- 

TTSl 

T 


ing  to  study  them,  or 
to  collect  them  for 
observation.  jSTever- 
theless,  Diptera  have 
considerable  claims  to 
be  classed  as  actually 
the  highest  of  Insects 
physiologically,  for  it 
is  certainly  in  them 
that  the  processes  of  a 
complete  life  -  history 
are  carried  on  with  the 
greatest  rapidity  and 
that  the  phenomena 
of  metamorphosis  have 

,  f          ,     FIG.  21 2. — A  Dipteron  (Fam.  Syrphidae),  Cheilosia  chryso- 

beeil  most  perfected.  coma.  Britain.  A,  Adult  larva ;  B,  the  pupa ;  C, 
A  mao-o-ot  hatchino1  nymph,  extracted  from  pupa;  D,  imago.  (From 

WeyeubergL.) 

irom   an   egg,  is   able 

to  grow  with  such  rapidity  that  the  work  of  its  life  in  this 
respect  is  completed  in  a  few  days  ;  then  forming  an  impene- 
trable skin  it  dissolves  itself  almost  completely  ;  solidifying  sub- 
sequently to  a  sort  of  jelly,  it  in  a  few  days  reconstructs  itself 
as  a  being  of  totally  different  appearance  and  habits,  in  all 
its  structures  so  profoundly  changed  from  what  it  was  that  the 
resources  of  science  are  severely  taxed  to  demonstrate  any 
identity  of  the  organs  of  the  two  instars. 

A  good  study  of  the  comparative  anatomy  of  Diptera  has  never 
been  made ;  Baron  Osten  Sacken,  one  of  our  most  accomplished 
Dipterologists,  has  recently  stated  that  "  the  external  characters 
of  the  Diptera  have  as  yet  been  very  insufficiently  studied." 
We  shall  therefore  only  trouble  the  student  with  a  few  observa- 
tions on  points  of  structure  that  are  of  special  importance,  or 
that  he  will  find  frequently  alluded  to.  The  head  is  remarkable 


44°  DIPTERA  CHAP. 

for  its  mobility,  and  is  connected  with  the  thorax  by  a  slender 
concealed  neck  that  permits  the  head  to  undergo  semi-rotation. 
A  large  part — sometimes  nearly  the  whole — of  the  exposed  sur- 
face of  the  head  is  occupied  by  the  faceted  eyes.  It  is  usually 
the  case  that  the  eyes  are  larger  in  the  male  than  in  the  female, 
and  the  sexual  discrepancy  in  this  respect  may  be  very  great. 
When  the  eyes  of  the  two  sides  meet  in  a  coadapted  line  of  union 
the  Insect  is  said  to  be  "  holoptic,"  and  when  the  eyes  are  well 
separated  "  dichoptic,"  The  holoptic  condition  is  specially  char- 
acteristic of  the  male,  but  in  some  forms  occurs  in  both  sexes. 
There  is  no  definite  distinction  between  holoptic  and  dichoptic 
eyes.  The  eyes  may  be  enormous,  Fig.  238,  without  actually  unit- 
ing, and  in  the  cases  where  actual  contiguity  occurs,  it  takes  place 
in  different  manners.2  The  eyes  are  frequently  during  life  of 
brilliant  colours  and  variegate  with  stripes  or  spots ;  this  con- 
dition disappears  speedily  after  death,  and  it  is  uncertain  what 
the  use  of  this  coloration  may  be.3  The  eyes  are  frequently 
densely  set  with  hairs  between  the  almost  innumerable  facets. 
These  facets  frequently  differ  in  size  according  to  their  position 
in  the  organ.  The  curious  double  eye  of  the  male  Bibio  (cf. 
Fig.  224)  is  well  worth  notice.  There  are  usually  three  small 
ocelli  placed  very  near  together  on  the  middle  of  the  summit  of 
the  head. 

The  antennae  are  of  considerable  importance,  as  they  offer 
one  of  the  readiest  means  of  classification.  The  families  placed 
by  systematists  at  the  commencement  of  the  Order  have  antennae 
similar  to  those  of  the  majority  of  Insects,  inasmuch  as  they 
consist  of  a  series  of  segments  approximately  similar  to  one 
another,  and  arranged  in  a  linear  manner  (Fig.  213,  A).  The 
number  of  these  joints  is  never  very  great,  but  reaches  sixteen 
in  certain  Tipulidae,  and  falls  as  low  as  eight  in  some  Bibionidae. 
In  certain  cases  where  the  antennae,  of  the  male  are  densely 
feathered  (Chironomus,  e.g.),  the  number  of  joints  is  in  that  sex 
greatly  augmented,  but  they  are  imperfectly  separated.  This 
form  of  antenna  gives  the  name  Nemocera  to  the  first  series  of 
Diptera.  The  majority  of  flies  have  antennae  of  another  form, 

1  Ostcn  Sacken,  Tr.  cut.   Soc.  London,   1884,  p.  501,  and  Berlin,   cnt.  Zcitschr. 
xxxvii.  1892,  p.  423,  etc. 

2  Ostrn  Sac/ken  has  recently  discussed  the  intermediate  conditions,  and  proposed 
the  ii.-iiin-  "  |isfii(lh«l(iptic  "  I'm-  si. me  of  them,  llcrliii.  cnt.  Zcitschr.  xli.  1896,  p.  367. 

3  Girschner,  /•'•  /•////.  ent.  /.<  ifschr.  xxxi.  1887,  p.  155. 


VII 


ANTENNAE 


441 


peculiar  to  the  Order,  viz.  three  segments,  the  outer  one  of 
which  is  of  diverse  form,  according  to  the  genus  or  species,  and 
bears  on  its  front  a  fine  projecting  bristle,  frequently  feathered, 
as  in  Fig.  213,  F  ;  and  often  distinctly  divided  into  two  or  more 
joints.  This  form  of  antenna  is  found  in  the  series  Aschiza  and 
Schizophora  ;  it  is  well  exemplified  in  the  common  house-fly,  where 
the  organs  in  question  hang  from  the  forehead,  and  are  placed  in 
a  hollow  formed  for  their  reception  on  the  front  of  the  head. 
Flies  with  this  form  of  antennae  are  called  Athericerous.  Between 
the  two  forms  of  antennae  we  have  mentioned  there  exists  what 
may,  speaking  roughly,  be  called  an  intermediate  condition,  or 


FIG.  213. — Antennae  of  flies.  A,  The  two  antennae  of  Glapliyroptera  picta  (Myceto- 
philidae) ;  B,  antenna  of  Hexatmna pellucens  (Tabanidae) ;  C,  of  Asihts  crabroniformis 
(Asilidae)  ;  D,  of  Leptis  scnlopiicea  (Leptidae)  ;  E,  of  Dolichopus  undulatus  (Doli- 
chopidae)  ;  F,  of  Vulucella  bombylans  (Syrphidae).  (After  Wandolleck.) 

rather  a  variety  of  intermediate  conditions,  associated  in  the 
series  Brachycera  (Fig.  213,  B  to  D).1  Here  there  are  three 
(sometimes  one  or  two)  segments  and  a  terminal  appendage, 
but  the  appendage  is  usually  compound  (often  so  distinctly  com- 
pound that  it  is  evidently  a  series  of  partially,  or  even  completely, 
separate  joints,  Fig.  213,  B) :  the  appendage  in  these  cases  is  ter- 
minal, that  is  to  say  it  is  placed,  not  as  in  the  Eumyiidae  on  the 
front  of  the  joint  that  bears  it,  but  (in  the  great  majority  of 
Brachycera)  at  the  tip  thereof;  this  appendage  is  often  conical 
and  pointed,  often  hair-like.  Exceptional  forms  of  antenna  are 
found  in  the  parasitic  flies  of  the  series  Pupipara.  In  the  Order 
generally  the  two  basal  joints  of  the  antennae  are  evidently 
distinct  in  function  from  the  others,  and  form  the  "  scape  "  ;  the 

1  It  may  be  well  to  remark  that  this  name  was  formerly  applied  to  all  Diptera 
except  Nemocera. 


442  DIPTERA  CHAP. 

part  of  the  antenna  beyond  the  scape  is  called  the  "  flagellum  "  ; 
an  appendage  of  the  flagellum  is  called  "  arista "  when  bristle- 
like,  when  thicker  "  style."  In  the  basal  joint  of  the  antenna 
there  is  a  complex  nervous  structure  known  as  Johnston's  organ. 
It  is  specially  well  developed  in  Culex  and  Chironomus,  and  is 
larger  in  the  male  than  it  is  in  the  female.  Child  has  found 
something  of  the  kind  present  in  all  the  Diptera  he  has 
examined,  and  he  considers  that  an  analogous  structure  exists  in 
Insects  of  other  Orders.  He  thinks  it  is  concerned  with  the 
perception  of  vibration,  there  being  no  sharp  distinction  between 
auditory  and  tactile  sensation.1 

About  one-half  of  the  Diptera  possess  a  peculiar  structure 
in  the  form  of  a  head -vesicle  called  "  ptilinum."  In  the  fly 
emerging  from  the  pupa  this  appears  as  a  bladder-like  expansion 
of  the  front  of  the  head;  being  susceptible  of  great  distension,  it 
is  useful  in  rupturing  the  hard  shell  in  which  the  creature  is  then 
enclosed.  In  the  mature  fly  the  ptilinum  is  completely  intro- 
verted, and  can  be  found  only  by  dissection ;  a  little  space,  the 
"  lunula,"  just  under  an  arched  suture,  extending  over  the  point 
of  insertion  of  the  anteuae  remains,  however,  and  offers  evidence 
of  the  existence  of  the  ptilinum.  This  structure  is  also  of 
importance  in  classification,  though,  unfortunately,  it  is  difficult 
to  verify.2 

Xo  point  of  Insect  morphology  has  given  rise  to  more  differ- 
ence of  opinion  than  the  mouth  of  Diptera  ;  and  the  subject  is 
still  very  far  from  being  completely  understood.  The  anatomy 
and  morphology  of  the  mandibulate  Insect-mouth  are  compara- 
tively simple  (though  not  without  greater  difficulties  than  are 
usually  appreciated) ;  and  it  has  been  the  desire  of  morphologists 
to  homologise  the  sucking  mouth  of  Diptera  with  the  biting 
mouth ;  hence  the  view  that  the  appendages  of  three  segments 
are  separate  and  distinct  in  the  fly's  mouth  is  taken  for  granted, 
and  it  is  further  assumed  that  some  of  the  secondary  parts  of  the 
;i]>]>endages  of  the  biting  mouth  can  also  be  recognised  in  the 
sucking  mouth.  The  anatomy  of  the  mouth-parts  is,  however, 

1  Zool.  Anz.  xvii.  1894,  p.  35,  and  Ann.  Nat.  Hist.  (6)  xiii.  1894,  p.  372  ;  Zcitschr. 
iviss.  Zool.  Iviii.  1895,  p.  475. 

-  <'i'.  Osten  Sacken,  Berlin,  ent.  Zcitschr.  xxxviii.  1893  ;  and  Beclier,  Jficn.  ent. 
Zcit.  i.  1882,  p.  49.  For  an  account  of  the  condition,  with  diagrammatic  figures, 
of  tin-  Ily  emerging  from  the  pupa,  cf.  Sasatti,  J.  Coll.  Japan,  i.  1SS7.  p.  34, 
pi.  vi. 


VII 


MOUTH-PARTS 


443 


subject  to  great  diversity  of  structure  within  the  limits  of  the 
Order  itself,  even  the  two  sexes  in  some  species  differing  pro- 
foundly in  this  respect.1  In  the  majority  of  the  family  Oestridae 
the  mouth-parts  are  practically  absent,  and  no  definite  entry  to 
the  alimentary  canal  can  be  perceived  (Fig.  245).  Besides  this 
condition  and  its  antithesis  (Fig.  214),  the  complex  assemblage 
of  lancets  seen  in  the  Breeze-flies  that  draw  blood,  there  is  a 
great  variety  of  other  anatomical  conditions. 

FIG.  214.— Mou tli -parts  of 
the  common  blood-suck- 
ing tiy,  Haematopota 
pluvw.lis  ?.  A,  Viewed 
from  beneath,  the  pro- 
boscis removed  ;  «, 
labrum  ;  b,  b,  cultelli 
(mandibles  of  other 
anatomists)  ;  c,  c,  scal- 
pella  (maxillae  of  other 
anatomists)  ;  d,  part  of 
ventral  scutum  of  second 
metamere  ;  e,  e,f,f,  parts 
of  palpi  ;  g,  hypopharynx 
and  pellucid  salivary 
duct  ;  k,  salivary  recep- 
tacle ;  i,  salivary  duct : 
I:  membranous  part  of 
second  metamere  ;  /. 
pharynx  :  B,  labrum, 
pharynx,  hypopharynx, 
separated,  seen  from 
beneath  ;  a,  labrum  ;  b, 
hypopharynx  ;  c,  salivary  duct  ;  d,  pharynx  ;  e,  protractor  muscles  :  C,  proboscis 
(labium)  from  beneath  ;  «,  scutum  proboscidis  ;  c,  c,  labella  ;  d,  d,  retractor  muscles. 
(After  Meinert). 

Although,  as  we  have  said,  great  diversity  of  opinion 
exists,  yet  on  the  whole  the  majority  of  Dipterologists  accept  a 
view  something  to  the  following  effect : — the  labrum,  or  the 
labrum  combined  with  the  epipharynx,  is  frequently  much  pro- 
longed ;  the  tongue — hypopharynx — may  also  be  much  prolonged, 
and  may  form,  in  apposition  with  the  labrum,  a  more  or  less  im- 
perfect tube  for  iugestion  of  the  nutriment ;  the  labium  is  more 
or  less  membranous  or  fleshy,  and  acts  as  a  sheathing  organ,  its 
tips — called  labella — being  in  some  cases  developed  to  a  quite 
extraordinary  extent.  As  to  the  other  parts  of  the  mouth  there 
is  less  agreement;  the  pointed  organs  (Fig.  214,  A,  b  6)  are  by 

1  It  is  frequently  said  that  one  sex  of  a  single  species  may  be  dimorphic  in  this 
respect,  but  we  shall  subsequently  mention  (in  Blepharoceridae)  that  this  is  not 
yet  sufficiently  established. 


A 


444  DIPTERA  CHAP. 

many  identified  as  mandibles,  while  another  pair  of  pointed  pro- 
cesses (c  c)  are  considered  to  lie  parts  of  a  maxilla,  and  the  palpi 
(//)  are  ^y  some  considered  to  be  maxillary  palps.  The  Danish 
entomologist,  Meinert,  has  published  the  best  anatomical  descrip- 
tion of  many  of  the  diverse  kinds  of  Dipterous  mouth.1  He, 
however,  takes  a  different  view  of  the  morphology ;  he  considers 
that  not  only  may  parts  of  the  appendages  of  the  mouth  be  much 
modified  during  the  early  stages  of  the  individual  development, 
but  that  they  may  be  differently  combined,  even  parts  of  the 
appendages  of  two  segments  being  brought  together  in  intimate 
combination.  He  has  also  pointed  out  that  the  mandibulate  and 
sucking  mouth  are  mechanical  implements  constructed  on  opposed 
principles ;  the  main  object  of  a  biting  mouth  being  the  fixing 
and  perfecting  of  the  articulations  of  the  mouth,  so  that  great 
power  of  holding  may  be  attained  with  a  limited  but  definite 
power  of  movement.  In  the  sucking  mouth  the  parts  are  in- 
timately associated  for  simple  protrusion.  Hence  the  two  kinds 
of  mouth  must  have  been  distinguished  very  'early  in  the 
phylogeny,  so  that  we  must  not  expect  to  find  a  great  corre- 
spondence between  the  parts  of  biting  and  sucking  mouths. 
He  apparently  also  considers  that  not  only  the  appendages  of 
a  head-segment,  but  also  part  of  the  body  of  the  segment,  may 
be  used  in  the  construction  of  the  mouth-organs.  Meinert's 
views  allow  a  much  greater  latitude  of  interpretation  of  the  parts 
of  the  Dipterous  mouth  ;  had  he  contented  himself  with  enun- 
ciating them  in  the  manner  we  have  followed  him  in  summarily 
describing,  they  would  have  been  recognised  as  a  formidable 
obstacle  to  the  facile  adoption  of  the  ordinary  views.  He  has, 
however,  accompanied  his  general  statement  with  a  particular 
interpretation  and  a  distinct  nomenclature,  neither  of  which  is  it 
possible  to  adopt  at  present,  as  they  have  no  more  justification 
than  the  ordinary  view.  So  that  instead  of  one  set  of  doubtful 
interpretations  we  have  two.'2  In  so  difficult  a  question  as  homo- 
logising  the  trophi  of  different  Orders  of  Insects  we  ought  to  use 

1  Flucrncs  Munddele,  Copenhagen,  1881,  91  pp.  6  plates;  Ent.  Tidskr.  i.  1879, 
p.  150  ;  Becher  having  given  (/><•,!/.•.  .//•.  ll'icn.  xlv.  1882,  p.  123)  an  interpreta- 
tion different  from  that  of  Meiriert,  this  author  set  forth  his  general  views  in 
Zool.  Anz.  v.  1882,  pp.  570  and  599. 

'  Tin*  reader  should  not  suppose  that  there  are  only  two  views  as  to  the  Dipterous 
muiit.li,  fur  actually  there  are  several  ;  uiir  ulject  is  here  only  to  give  a  general  idea 
of  the  subject. 


vii  STRUCTURE  445 

exhaustively  every  method  of  inquiry  :  and  from  this  point  of 
view  the  development  is  of  great  importance.  This  has,  however, 
as  yet  thrown  but  little  light  on  the  subject,  this  study  being  a 
very  difficult  one  owing  to  the  profound  changes  that  take  place 
during  metamorphosis,  the  diversity  of  the  parts  in  the  early 
stages  of  Diptera,  and  the  possibility  that  the  larval  conditions 
may  themselves  have  been  greatly  changed  in  the  course  of  the 
phylogeny.  Miall  informs  us,  however,  that  in  Chironomus  as 
well  as  in  Corethra  the  new  parts  of  the  mouth  of  the  imago  are 
developed  within  those  of  the  larva.1  This  may  permit  of  an 
identification  of  the  main  divisions  of  the  mouth,  at  any  rate  in 
these  cases.  Lowne  has  to  some  extent  traced  the  development 
in  the  blowfly,  and  he  does  not  agree  with  the  usual  interpreta- 
tion of  the  parts  in  the  adult. 

The  mouth  is  of  considerable  importance  in  the  classification 
of  Diptera.  The  Neniocera  are  remarkable  from  the  linear  de- 
velopment and  flexibility  of  the  palpi,  which  are  nearly  always  at 
least  three-  or  four-jointed  ;  this  condition  occurring  in  no  other 
Diptera.  The  palpi  attain  an  extraordinary  development  in  some 
Culicidae ;  in  the  genus  Meyarrhina  they  are  nearly  as  long  as 
the  body,  and  project  in  front  of  the  head  after  the  fashion  of 
the  palpi  of  Lepidoptera.  In  the  Brachycera  the  sclerites  or 
hard  parts  of  the  mouth  reach  a  maximum  of  development,  and 
in  Tabanidae  (Fig.  214),  Nemestrinidae  and  Bqmbyliidae  are 
often  quite  disproportionate  to  the  size  of  the  Insect.  In  many 
of  the  Eumyiid  flies  the  soft  parts  are  greatly  developed,  and 
capable  of  a  variety  of  movement,  the  proboscis  as  a  whole  being 
protrusible,  and  having  an  elbow-joint  in  the  middle. 

The  thorax  is  remarkable  from  the  absence  of  distinct  separa- 
tion into  the  three  divisions  that  may  usually  be  so  easily  dis- 
tinguished in  Insects.  The  perfect  combination  of  the  three 
segments  adds  much  to  the  difficulty  of  arriving  at  general  con- 
clusions as  to  the  identification  of  the  parts;  hence  considerable 
difference  of  opinion  still  prevails.  It  was  formerly  supposed 
that  a  segment  from  the  abdomen  was  added  to  the  thorax  of 
Diptera  as  it  is  in  Hymenoptera,  but  this  has  been  shown  by 
Brauer  to  be  erroneous.  Indeed,  according  to  Lowne,  the  abdo- 
minal cavity  is  increased  by  the  addition  of  the  small  posterior 
area  of  the  thorax  ;  it  being  the  mesophragma  that  separates  the 

1   Tr.  Linn.  Soc.  London  (2)  v.  1892,  p.  271. 


44 6  DIPTERA 


CHAP. 


second  and  third  great  divisions  of  the  body-cavity.  The  pro- 
thorax  is  always  small,  except  in  a  few  of  the  abnormal  wingless 
forms  (Melophagus)  \  in  A//<7< >,•//>/</  (Fig.  248)  the  mesothorax 
forms  the  anterior  part  of  the  body  ;  the  head  and  such  parts  of 
the  prothorax  as  may  be  subsequently  discovered  to  exist  being 
placed  entirely  on  the  dorsum  of  the  body.  The  mesothorax  in 
all  the  winged  Diptera  forms  by  far  the  larger  portion  of  the 
thoracic  mass,  the  prominent  part  of  it,  that  projects  backwards 
to  a  greater  or  less  extent  over  the  base  of  the  abdomen,  being 
the  scutellurn.  The  first  or  prothoracic  stigma  is  remarkably  large 
and  distinct,  and  is  by  some  called  mesothoracic.  Another  large 
stigma  is  placed  very  near  to  the  halter  (or  balancer) ;  the  meta- 
thorax  being  very  small.  An  imperfect  stigma  is  said  by  Lowne 
to  exist  in  the  blowfly  near  the  base  of  the  wing.  The  number 
of  abdominal  segments  externally  -visible  is  very  diverse  ;  there  may 
be  as  many  as  nine  (in  the  male  Tipulci],  or  as  few  as  five,  or  even 
four,  when  the  basal  segment  is  much  concealed  ;  the  diminu- 
tion is  due  to  certain  segments  at  the  extremity  being  indrawn 
and  serving  as  a  sort  of  tubular  ovipositor  in  the  female,  or  curled 
under  the  body  and  altered  in  form  in  the  other  sex,  so  as  to 
constitute  what  is  called  a  "  hypopygium."  In  the  female  of 
Tipulidae  the  body  is  terminated  by  some  horny  pieces  forming 
an  external  ovipositor.  In  nearly  all  Diptera  the  feet  are  five- 
jointed  ;  the  claws  are  well  developed,  there  being  placed  under 
each  of  them  a  free  pad  or  membrane,  the  "  pulvillus  "  ;  there  may 
be  also  a  median  structure  between  each  pair  of  claws,  of  diverse 
form,  the  "  empodium." 

On  the  surface  of  the  body  of  many  flies  there  will  be  seen 
an  armature  of  pointed  bristles ;  these  flies  are  called  "  chaeto- 
phorous  "  ;  where  no  regularly  arranged  system  of  such  bristles 
exists  the  fly  is  "  eremochaetous."  In  some  families  the  arrange- 
ment of  these  bristles  is  of  importance  in  classification,  and  a 
system  of  description  has  been  drawn  up  by  Baron  Osteu 
Sacken :  this  branch  of  descriptive  entomology  is  known  as 
chaetotaxy.1 

The  wings  are  of  great  importance  in  classifying  Diptera  ; 
but  unfortunately,  like  the  other  parts,  they  have  not  received  an 
exhaustive  anatomical  study,  and  Dipterologists  are  not  agreed 
as  1«  the  names  that  should  be  applied  to  their  parts.  We  give 

1    Tr.  cut.  Soc.  London,  1884,  p.  497. 


VII 


WINGS 


447 


below  figures  of  two  systems  that  have  been  used  by  eminent 
Dipterologists  for  the  description  of  the  nervures  and  cells.  The 
comprehension  of  these  features  of  the  Dipterous  wing  will  be  facili- 
tated by  noticing  that  the  wing — being  extended  at  right  angles  to 
the  body — is  divided  by  the  longitudinal  nervures  into  two  great 
fields,  anterior  and  posterior,  with  an  interval  between  them : 
this  interval  is  traversed  only  by  a  short  cross-vein  (marked  x  in 
Fif.  215  A,  and  i  in  B).  This  cross-vein  may  be  placed  near  the 
base  or  nearer  to  the  tip  of  the  wing  ;  it  is  of  importance  because 
no  nervure  in  front  of  the  median  area  traversed  by  it  can  corre- 

Fiu.  215. — Nervuration  of  Dipterous 
wing.  A,  Wing  of  a  Tipulid,  accord- 
ing to  Loew,  who  uses  the  following 
nomenclature  :  a,  costal  nervure  ;  b, 
medlastinal  ;  c,  subcostal  ;  d,  radial  ; 
e,  cubital  ;  /,  discoidal  ;  g,  postical  ; 
A,  anal;  -i,  axillar ;  x,  transverse, 
y,  posterior  transverse,  nervure  ; 
1,  2,  mediastinal  areas  ;  3,  sub- 
costal ;  4,  cubital  ;  5,  anterior  basal ; 
6,  posterior  basal  ;  7,  anal  ;  8,  pos- 
terior marginal  ;  9,  discoidal.  B, 
Wing  of  an  Acalypterate  Muscid 
(Ortalis),  according  to  Schiner,  who 
uses  the  following  nomenclature : 
(nervures,  small  letters  ;  cells,  capi- 
tal letters)  :  a,  transverse  shoulder  ; 
b,  auxiliary  ;  c  to  k,  first  to  sixth 
longitudinal  ;  i,  middle  transverse  ; 
k,  posterior  transverse  ;  I,  m,  n,  o, 

costa  ;  p,  anterior  basal  transverse  ;  g,  posterior  basal  transverse  ;  r,  rudiment  of  a  fourth 

nervure  ;  s,  axillary  incision  :  A,  B,  C,  first,  second,  and  third  costal  cells  ;  D,  marginal  ; 

E,  sub-marginal  ;  F,  G,  H,  first,  second,  and  third  posterior  ;  I,  discal ;  E,  L,  M,  first, 

second,  and  third  basal  cells  ;  N,  anal  angle  ;  O,  alula. 

spond  with  a  nervure  placed  behind  it  in  another  wing.  The 
very  different  nature  of  the  nervuration  in  the  two  wings  we  have 
figured  will  readily  be  appreciated  by  an  inspection  of  the  parts 
posterior  to  the  little  cross-vein.  On  the  hind  margin  of  the 
wing,  near  the  base,  there  is  often  a  more  or  less  free  lobe  (Fig. 
215,  B,  0)  called  the  "  alula  "  :  still  nearer  to  the  base,  or  placed  on 
the  side  of  the  body,  may  be  seen  one  or  two  other  lobes,  of  which 
the  one  nearer  the  alula  is  called  the  "  tegula,"  or  (when  a 
lobe  behind  it  is  also  present)  the  "  upper  tegula,"  (the  "anti- 
tegula  "  of  Osten  Sacken) ;  the  other  being  the  "  lower  tegula." 
These  two  terms  are  erroneous,  the  word  tegula  being  definitely 
applied  to  another  part  of  the  Insect-body.  In  speaking  of  this 
structure  in  the  following  pages,  we  have  preferred  to  call  it  the 


DIPTERA 


CHAP. 


"  squama."        Those  Muscidae  in  which   the   squama  covers   the 
halter  like  a  hood  are  called"  calypterate."      In   Fig.    216,   we 

represent  these  structures,  and  in 
the  explanation  have  mentioned  the 
synonyms.  The  terms  we  think 
most  applicable  to  the  three  lobes 
are  alula,  antisquama,  squama.  The 
squama  may  be  called  "  calypter " 
when  it  covers  the  halter. 

The    halteres — commonly    called 
FIG.  216.— Parts  at  the  base  of  the  kaiaucers    or     poisers — are    perhaps 

wing  in    Calliphora.       a,    Anal  A 

angle  or  lobe  of  the  wing ;  b,    the    most    characteristic    of    all    the 

alula ;    c,     antisquama,     .squama    Dipterous   Structures,   though  they  are 
alaris,  or  antitegula  ;  ((,  squama,  .  .  . 

squama  thoracicalis,  tegula,  caly-    absent    111     lllOSt     01    the    few    wingleSS 

pter,  or  calyptron  ;  e    posterior    forms  fjf  the  Or(ler.       Outside  the  Dip- 

extremity    (scutellum)    ot     the 

mesothorax ;  /,  scutum  of  nieso-   tera   similar    organs   appear   to  exist 
thorax>  only  in'  male  Coccidae.      The  pair  of 

halteres  is  placed  on  the  metathorax,  one  on  each  of  the  pleura! 
regions.  They  are  believed  to  be  the  homologues  of  the  hind 
wings;  Weinland  states  2  that  certain  canals  existing  in  the  interior 
of  the  halter  correspond  to  wing-iiervures.  The  halter  may  be 
described  as  a  small  rod-like  body  with  a  head  like  a  pin,  this 
terminal  part  being,  however,  rather  variable  in  form.  "We 
have  already  stated  that  in  many  Diptera  the  squama  forms  a 
hood,  the  position  of  which  leads  to  the  belief  that  it  is  an 
important  adjunct  to  the  halter.  Although  the  exact  functions 
of  the  halteres  are  far  from  clear,  it  is  certain  that  they  are 
highly  complex  bodies,  of  extremely  delicate  structure  :  they  are 
doubtless  sense-organs,  possessing  as  they  do,  groups  of  papillae 
on  the  exterior  and  a  chordotonal  organ  (a  structure  for  assist- 
ing the  perception  of  sound)  in  the  basal  part ;  each  halter 
is  provided  with  four  muscles  at  the  base,  and  can,  like  the 
wings,  execute  most  rapid  vibrations.  Seeing  that  they  are  the 
homologues  of  wings,  it  is  a  remarkable  fact  that  in  no  Diptera 
are  they  replaced  by  wings,  or  by  structures  intermediate  between 
these  two  kinds  of  organs. 

Internal  Structure. — Information  about  the  internal  anatomy 

1  Osten  Sacken,    although    making    use   of  llir    trims   tegula    and    antitegula, 
suggest  I'd  the  propriety  of  using  si|ii,im;i  .-iml  antisqvmrna,  as  \ve  have  done. 
-  /i-ilKi-lir.  wiss.  '/.«»/.  li.  1891,  p.  55. 


vii  ANATOMY LARVAE  449 

is  by  no  means  extensive.  The  tracheal  system  is  highly  developed, 
and  has  air-sacs  connected  with  it ;  a  large  pair  at  the  base  of 
the  abdomen  being  called  aerostats  by  Dufour.  Inside  the 
thoracic  spiracles  there  are  peculiar  structures  supposed  by  some 
to  be  voice-organs,  while  the  abdominal  spiracles  are  said  to  be 
remarkably  simple  in  structure.  Lowiie  says  that  there  are  ten 
or  eleven  pairs  of  spiracles  in  the  Blow-fly  ;  one  of  these,  near 
the  base  of  the  wing,  is  peculiar  in  structure,  and  may  not.  be 
a  true  stigma  ;  he  calls  it  a  tympanic  spiracle ;  it  seems-  doubtful 
whether  there  are  more  than  seven  abdominal  pairs.  The  alimen- 
tary canal  is  very  elongate,  and  is  provided  with  a  diverticulum, 
the  crop;  this  is  usually  called  the  sucking  stomach,  though  its  func- 
tion is  extremely  doubtful.  The  Malpighiaii  tubes  are  four  in 
number,  and  are  very  elongate  ;  in  several  groups  of  Nemocera 
there  are,  however,  five  Malpighiaii  tubes,  a  number  known  to 
occur  in  only  very  few  other  Insects.  The  nervous  system  is 
remarkable  on  account  of  the  concentration  of  ganglia  in  the 
thorax,  so  as  to  form  a  thoracic,  in  addition  to  the  usual  cephalic, 
brain.  For  particulars  as  to  the  positions  of  the  ganglia  and  the 
great  changes  that  occur  in  the  lifetime,  the  student  should 
refer  to  Brandt,  to  Kiinckel,  and  to  Brauer.1  Much  information 
as  to  the  internal  anatomy  of  the  Blowfly  is  given  by  Lowne,  but 
it  is  doubtful  to  what  extent  it  is  applicable  to  Diptera  in 
general.2 

The  larvae  of  Piptera  are — so  far  as  the  unaided  eye  is 
concerned — without  exception  destitute  of  any  kind  of  adorn- 
ment, the  vast  majority  of  them  being  of  the  kind  known  as 
maggots.  None  of  them  have 
true  thoracic  legs ;  though  in 
the  earlier  groups,  pseudopods 

f     ,-,         T       -, 

or  protuberances  ot   the   body 

that  Serve  as  aids  in  loCOlllO-  FIG.  217. — Acephalous  larva  or  maggot  of  the 
tioil  are  common.  Unlike  Ho^fly,  with  the  head,  a,  extended.  (After 

what    occurs  in  other  Orders 

the  arrangement  of  these  pseudopods  on  the  body  differs  greatly 

in    various    forms;    in    a    few    cases    they    are    surmounted    by 

1  Brandt,  Horac  Soc.  cut.  Ross.  xiv.  1878,  p.  vii.  ;  xv.  1879,  p.  20.  Brauer, 
Dcnk.  Ak.  W-icn,  xlvii.  1SS3,  pp.  12-16.  Kiinckel,  C.E.  Ac.  Paris,  Ixxxrx.  1879, 
p.  491. 

-  Bloic-fiy,  1S95  :  in  two  vols.  For  Anatomy  of  Volucelld,  see  Kiinckel 
d'Herculais,  Jtcchcrchcs  sur  Vorg.  des  Volucelles,  Paris,  1875  and  1881. 

VOL.   VI  2   G 


45°  DIPTERA  CHAP. 

curved  hairs.  The  most  important  distinction  in  external  form 
in  Dipterous  larvae  is  that  while  those  that  are  thorough  maggots 
possess  no  visible  head,  others  have  a  well-marked  one  (Fig. 
225);  these  are  therefore  called  "  eucephalous " :  they  have  a 
mouth  of  the  mandihulate  type.  In  some  other  Dipterous  larvae 
the  head  is  more  or  less  reduced  in  size,  and  in  the  acephalous  forms 
there  is  only  a  framework  of  a  few  chitinous  rods  to  represent 
it.  The  nervous  system  in  the  most  completely  headless  larvae 
is  very  remarkable,  all  the  ganglia  being  concentrated  in  a  single 
mass  placed  in  the  thorax.  The  tracheal  system  exhibits  a  great 
variety ;  some  larvae  have  stigmata  arranged  along  the  sides  of 
the  body  after  the  fashion  normal  in  Insect-larvae ;  these  are 
called  "  peripneustic  "  ;  as  many  as  ten  pairs  of  stigmata  may  be 
present  in  these  cases,  but  nine  pairs  is  much  more  common. 
Other  larvae  have  a  pair  of  stigmata  placed  at  the  termination  of 
the  body,  and  another  pair  near  the  anterior  extremity,  the  two 
pairs  communicating  by  large  tracheal  trunks  extending  the 
length  of  the  body  ;  these  larvae  are  said  to  be  "  amphipneustic  "  : 
this  is  the  condition  usual  in  the  more  completely  acephalous 
larvae.  Others  have  only  the  terminal  pair  of  spiracles,  and  are 
styled  "  metapneustic."  Some  begin  life  in  the  metapneustic  state 
.and  afterwards  become  amphipneustic.  In  the  aquatic  larva 
of  Corethra  there  are  no  spiracles,  though  there  is  an  imperfect 
tracheal  system.  Many  Dipterous  larvae  that  live  in  water 
or  in  conditions  that  prevent  access  of  air  to  the  body  have 
remarkable  arrangements  for  keeping  the  tip  of  the  body  in 
communication  with  the  atmosphere.  The  stigmata  in  meta- 
pneustic and  amphipneustic  larvae  are  very  remarkable  compound 
structures,  exhibiting  however  great  diversity  ;  their  peculiarities 
and  uses  are  not  well  understood ;  it  appears  very  doubtful 
whether  some  of  them  have  any  external  opening.  Eeference 
may  be  made,  as  to  the  variety  of  structure,  to  Meijere's  paper1 
from  which  we  take  the  accompanying  figure  of  a  posterior 
stigmatic  apparatus  in  Lipara  liu-ens.  It  appears  that  there  is  a 
compound  chamber — "  Filzkammer  "  —terminating  externally  in 
lobes  or  fingers  -"Knospen"  and  appearing  as  marks  on  the 
miter  surface:  this  chamber  is  seated  on  a  tracheal  tube,  and  is, 
Mfijere  thinks,  probably  a  secondary  growth  of  the  trachea 
coining  to  the  outer  surface.  It  is  traversed  by  what  may  be 

1   Tijdschr.  Ent.  xxxviii.  1S95,  pp.  65-100. 


VII 


LARVA PUPA 


451 


enor 

stigma  of  the  larva  of  Lip- 
am  lucens.  «,  One  of  the 
three  "  Knospen  "  or  lobes  ; 
b,  external  stigmatic  scar ; 
<.',  internal  scar ;  d,  stig- 
matic chamber  (Filzkam- 
mer)  ;  e,  trachea.  (After 
Meijere.) 


considered    the  original  tracheal  tube,  opening  externally  as  an 

external  stigmatic  scar — "  Stigmennarbe  "  —and  with  a  second 

or  inner  scar  placed  internally.      We  may 

conclude    from    what    is    already   known 

that    these    structures  will    be    found  to 

differ  in  the  same  larva  according  to  the 

stage  of  its  development. 

An  extremely  valuable  summary  of 
the  characters  and  variety  of  Dipterous 
larvae  has  been  given  by  Brauer,1  from 
which  it  appears  that  the  larvae  of  the 
first  half  of  the  family  exhibit  great 
variety  and  have  been  much  studied,  FlG-  218.— The  post 
while  the  more  purely  maggot-like  forms 
of  the  Muscidae  have,  with  one  or  two 
exceptions,  been  little  investigated. 

The  pupal  instar  is  of  two  distinct 
kinds.  First,  we  meet  with  a  pupa  like  that 
of  Lepidoptera,  viz.  a  mummy-like  object, 
or  pupa  obtecta,  in  which  there  is  a  crisp  outer  shell,  formed 
in  part  by  the  adherent  cases  of  the  appendages  of  the  future 
imago.  This  condition,  with  a  few  exceptions  to  be  subsequently 
noticed,  obtains  in  the  Nemocera  and  Brachycera.  It  is  exhibited 
in  various  degrees  of  perfection,  being  most  complete  in  Tipulidae  ; 
in  other  forms  the  shell  is  softer  and  the  appendages  more  pro- 
tuberant. The  second  kind  of  pupa  is  found  in  the  Cyclor- 
rhaphous  flies ;  it  has  externally  no  marks  except  some  faint 
circular  rings  and,  frequently,  a  pair  of  projections  from  near 
one  extremity  of  the  body ;  occasionally  there  is  a  single  pro- 
minence at  the  other  extremity  of  the  body.  This  condition  is 
due  to  the  fact  that  the  larva  does  not  escape  from  the  skin 
at  the  last  ecdysis,  but  merely  shrinks  within  it,  so  that  the 
larval  skin,  itself  contracted  and  altered  by  an  excretion  of 
chitin,  remains  and  forms  a  perfect  protection  to  the  included 
organism.  This  kind  of  pupa  looks  like  a  seed,  and  is  well 
exemplified  by  the  common  Blow-fly.  The  capacity  for  entering 
on  such  a  condition  is  evidently  correlative  with  the  absence  of  a 
larval  head.  The  metamorphosis  in  this  curious  little  barrel 
goes  on  in  a  different  manner  to  what  it  does  in  the  pupa 

1  Denk.  Ak.   Wicn,  xlvii.  1883,  pp.  1-100,  pis.  i.-v. 


45 2  DIPTERA  CHAP. 

obtecta.  A  good  name  for  the  whole  structure  of  this  instar 
has  not  been  found.  Older  authors  called  it  "  pupa  coarctata," 
or  "  nympha  inclusa "  ;  Brauer  speaks  of  it  as  a  "  compound 
pupa " ;  ordinarily  in  our  language  it  is  called  a  "  puparium,"  a 
term  which  is  more  applicable  to  the  case  alone. 

In  species  having  a  pupa  obtecta  the  larval  skin  is  cast  after 
the  chief  processes  of  the  external  metamorphosis  have  occurred, 
iind  then  an  exudation  of  chitin  hardens  the  general  surface. 
In  the  "  compound  pupa  "  of  the  Blow-fly  there  is  for  a  consider- 
able period  no  formed  pupa  at  all,  but  merely  a  shell  or  case 
containing  the  results  of  histolysis  and  the  centres  for  regenera- 
tion of  new  organs ;  the  chitin-exudation  to  the  exterior  of  the 
larval  skin  occurs  in  the  early  part  of  the  series  of  metamorphic 
changes,  and  the  organism  breaks  down  to  a  cream  within  the  shell 
thus  formed,  and  then  gradually  assumes  therein  the  condition  of  a 
soft,  nymphoid  pupa.  The  exceptional  conditions  previously  re- 
ferred to  as  exhibited  by  a  few  forms  are  certain  cases  in  which  a 
more  or  less  perfect  pupa  obtecta  is  found  within  the  last  larval 
skin,  as  is  the  case  in  Stratiomys.  Another  highly  remarkable 
condition  exists  in  the  Hessian  fly,  and  a  few  other  Cecidomyiids, 
where  the  Insect  apparently  makes  an  exudation  which  it  uses 
as  a  covering  case,  independent  of  the  larval  skin  ;  this  latter 
being  subsequently  shed  inside  the  case,  so  that  this  condition 
of  coarctate  pupa  differs  from  that  we  have  described  as  exist- 
ing in  Cyclorrhaphous  flies,  although  the  two  are  superficially 
similar.  In  the  Pupipara  the  larval  stage  is  passed  in  the  body 
of  the  mother,  which  produces  a  succession  of  young,  nourished 
one  at  a  time  by  the  secretion  of  glands  ;  this  young  is  born  as 
a  full-grown  larva  that  becomes  at  once  a  pupa. 

Metamorphosis. — As  it  is  in  Diptera  that  the  phenomena 
of  Insect-metamorphosis  have  reached  their  highest  development 
we  endeavoured  to  give  some  idea  of  their  nature  in  the  previous 
volume,  therefore  we  need  give  only  a  brief  sketch  of  the  chief 
features  of  Dipterous  metamorphosis.  The  Blow-fly  undergoes  a 
rapid  embryonic  development,  the  later  stages  of  which  are,  on 
the  whole,  of  a  retrogressive  nature.  On  the  emergence  of  the 
young  maggot  it  feeds  up  rapidly,  the  rapidity  varying  greatly 
according  to  circumstances,  and  then  when  full-grown  rests. 
While  resting,  a  process  of  internal  liquefaction,  called  histolysis, 
is  going  on,  and  the  maggot  contracts  and  exudes  an  excretion 


vii  METAMORPHOSIS  453 

that  hardens  its  skin.  At  the  time  this  hard  skin  has  become 
complete,  or  soon  after,  the  maggot  inside  has  dissolved  into  a 
cream  contained  in  a  sac  inside  the  shell ;  this  cream  becomes 
reconstituted  into  a  fly  by  a  gradual  process  of  growth  and 
development  of  certain  minute  portions  of  the  body — the 
imaginal  discs  or  folds,  the  histoblasts  and  neuroblasts  that 
were  exempt  from  the  histolytic  process  :  in  the  early  stages 
of  the  reconstitution  the  general  structure  is,  of  course,  altogether 
vague,  and  this  condition — purely  one  of  transition — is  called 
the  pronymph ;  the  nymph  becomes  gradually  developed :  it 
corresponds  vaguely  with  the  pupa  obtecta  of  the  early  groups 
of  Diptera,  but  is  soft  like  the  pupa  of  Hymenoptera.  This 
nymph  gradually  develops  into  the  fly  itself,  the  external 
parts  being  first  completed  and  the  internal  organs  elaborated 
subsequently.  The  sexual  organs  do  not  undergo  metamorphosis 
like  other  internal  organs,  there  being  a  gradual  (though  ir- 
regular or  interrupted)  growth  of  them  in  the  young  larva,  till 
they  are  completed  some  time  after  the  emergence  of  the  perfect 
fly.  The  processes  in  the  Blow-fly  have  been  studied  by  numerous 
able  histologists  of  various  nationalities,  and  have  recent]y  been 
described  by  Lowne  in  our  own  language.1  Comparatively  little 
has  been  done  in  studying  the  corresponding  phenomena  in  other 
Diptera.  Weismann  has  investigated  the  development  of  Corethra, 
and  Miall  that  of  Chironomus.  These  two  flies  belong  to  a  division 
of  Diptera  different  from  that  which  includes  the  Blow-fly,  and 
they  display  a  condition  of  the  metamorphic  processes  allied  to 
what  occurs  in  Lepidoptera,  as  wrell  as  to  that  which  takes  place  in 
the  Blo\v-fly.  Imaginal  folds  are  formed,  but  they  only  appear 
much  later  in  the  life,  and  they  are  much  less  distant  from  the 
positions  they  will,  when  developed,  occupy  in  the  imago.  In 
Chironomus,  according  to  Miall,  the  imaginal  folds  only  appear 
in  the  last  larval  instar,  but  they  grow  with  such  rapidity  that 
the  legs  and  wings  of  the  future  fly  can  be  distinguished  in  the 
larva,  even  before  pupation ;  thus  when  the  activity  of  the  larva 
ceases  but  little  change  is  required  to  complete  the  obtected 
pupa.  In  the  Blow-fly  some  of  the  imaginal  folds  have  been 

1  Since  our  brief  and  imperfect  sketch  of  metamorphosis  appeared  in  Vol.  Y.  of 
this  series,  Packard  has  treated  the  subject  more  fully  in  his  Text-book  of  Entomology, 
New  York,  1898  ;  and  Pratt  has  summarised  the  state  of  knowledge  as  to  imaginal 
discs  in  Psyche,  viii.  1897,  p.  15,  etc. 


454  DIPTERA  CHAP. 

traced  buck  to  the  embryo ;  how  many  centres  for  the  new 
growth  there  may  be  is  uncertain,  for  though  there  are  upwards 
of  sixty  for  the  outer  body,  the  number  of  regenerative  centres 
for  the  internal  organs  is  not  ascertained.  The  peculiar  central 
nervous  mass,  mentioned  in  our  remarks  on  the  larva,  consists  of 
two  kinds  of  tissue  mixed  together  in  a  complex  manner ;  one 
of  these  kinds  is  functionally  active  during  the  larval  life  and 
at  the  metamorphosis  undergoes  histolysis,  while  the  other,  or 
embryonic,  portion  develops  into  the  nervous  system  of  the  fly. 

It  forms  no  part  of  our  task  to  deal  with  general  subjects, 
but  wTe  may  be  pardoned  for  calling  attention  to  the  bearing  the 
metamorphosis  of  the  higher  Diptera  has  on  our  ideas  of  heredity 
in  Insects.  The  fly  bears  no  resemblance  whatever  to  the  larva, 
and  is  only  obtained  by  the  organic  destruction  of  the  latter, 
which  occurs  before  the  perfection  of  the  sexual  organs  takes 
place,  and  yet  the  fly  reproduces  itself  only  secondarily,  but 
primarily  gives  rise  to  the  totally  different  larva.  It  is  supposed 
that  the  larval  structures  have  been  gradually  acquired,  and  yet 
they  are  transmitted  with  the  utmost  faithfulness  by  the  totally 
different  fly.  We  can  only  conclude  that  that  which  is  bequeathed 
in  each  species  is  the  early  state  of  a  particular  process  of  develop- 
ment from  which  the  subsequent  stages  follow  necessarily  if  the 
developing  organism  be  placed  in  conditions  having  on  it  in- 
fluences like  to  those  that  influenced  the  ancestors. 

Classification. — The  classification  of  Diptera  is  as  yet  very 
imperfect.  Formerly  they  were  divided  into  two  great  groups, 
Nemocera  and  Brachycera,  according  to  the  structure  of  the 
antennae,  as  previously  mentioned.  This  division  has  been 
abandoned,  and  the  term  Brachycera  is  now  applied  to  only  a 
small  part  of  the  old  section  that  bore  the  name.  The  primary- 
division  usually  adopted  at  present  is  into  Orthorrhapha  and 
Cyclorrhapha.  The  characters  of  these  two  groups  are  based 
on  the  nature  of  the  metamorphosis,  and  have  been  gradually 
elaborated  by  Brauer  in  various  memoirs.1  The  Orthorrhapha 
includes  the  forms  with  obtected  pupae,  the  Cyclorrhapha  those 
with  a  nymph -compound,  as  previously  described.  This  distinction 
is  of  great  importance,  but  unfortunately  it  is  difficult  to  apply 
to  the  fly  itself;  the  only  character  that  can  be  used  in  eonnec- 

1  Monograph  of  Oestridae,    Vcrli.   Ges.    Wicn,  1863,  and  other  papers  op.  cit. 
1864,  1867,  1869  ;  also  Dcuk.  Ak.   Jficii,  xlii.  18SO,  xlvii.  1883. 


vii  CLASSIFICATION  455 

tion  with  the  imago  is  the  existence  of  a  suture  over  the  insertion 
of  the  antennae  in  a  portion,  but  not  all,  of  the  Cyclorrhapha.1 
The  next  set  of  divisions  used  by  Brauer  divides  the  Order  into 
four  sections,  viz.  1.  Orthorrhapha  Nematocera,  2.  0.  Brachycera, 
3.  Cyclorrhapha  Aschiza,  4.  C.  Schizophora.  As  these  four 
groups  are  recognised  more  readily  than  the  two  major  groups 
the  student  will  do  well  at  first  to  disregard  the  primary  division 
and  consider  the  Diptera  as  divisible  into  four  great  groups.  To 
these  four  divisions  we,  however,  add  temporarily  a  fifth,  viz. 
Pupipara,  This  is  included  by  Brauer  in  Schizophora,  but  it 
appears  to  be  really  an  unnatural  complex,  and  had  better  be 
kept  separate  till  it  has  been  entirely  reconsidered.  These 
great  sections  may  be  thus  summarised  :— 

Series  1.  Orthorrhapha  Nemocera. — Antennae  with  more  than  6  segments, 
not  terminated  by  an  arista  ;  with  the  segments  of  the  flagellum 
more  or  less  similar  to  one  another.  Palpi  slender  and  flexible, 
four-  or  five-jointed.2 

Series  2.  Orthorrhapha  Brachycera.  —  Antennae  variable,  but  never  truly 
Nemocerous  nor  like  those  of  Cyclorrhapha  ;  when  an  arista  is 
present  it  is  usually  placed  terminally,  not  superiorly  ;  when  an 
arista  is  not  present  the  flagellum  terminates  as  an  appendage 
consisting  of  a  variable  number  of  indistinctly  separated  segments  ; 
thus  the  flagellum  is  not  composed  of  similar  joints  ;  [rarely  are  the 
antennae  as  many  as  seven-jointed].  Palpi  only  one-  or  two- 
jointed.3  Around  the  insertion  of  the  antennae  there  is  no  definite 
arched  suture  enclosing  a  small  depressed  space.  The  nervuration 
of  the  wings  is  usually  more  complex  than  in  any  of  the  other 
divisions. 

Series  3.  Cyclorrhapha  Aschiza.  Antennae  composed  of  not  more  than  three 
joints  and  an  arista ;  the  latter  is  not  terminal.  Front  of  head 
without  definite  arched  suture  over  the  antennae,  but  frequently 
with  a  minute  area  of  different  colour  or  texture  there.  This  group 
consists  of  the  great  family  Syrphidae,  and  of  four  small  families, 
viz.  Conopidae,  Pipunculidae,  Phoridae,  and  Platypezidae.  The 
section  is  supposed  to  be  justified  by  its  being  Cyclorrhaphous  in 
pupation,  and  by  the  members  not  possessing  a  ptilinum  (or  having 
no  trace  of  one  when  quite  mature).  The  Syrphidae  are  doubtless 

1  Becher,  Wicn.  Ent.  Zcit.  i.  1882,  p.  49  ;  for  observation  on  connecting  forms 
see  Brauer,  Verh.  Ges.  JVien,  xl.  1890,  p.  272. 

'•  The  palpi  are  said  to  be  of  only  one  segment  in  some  genera  of  Cecidomyiidae. 
The  Cecidomyiidae  are  easily  distinguished  by  the  minute  size — body  not  more 
than  a  line  long — and  by  there  not  being  more  than  six  nervules  at  the  periphery 
of  the  wing.  Aedes  (Culicidae)  has  also  short  palpi. 

3  It  is  said  by  Schiner  that  in  the  anomalous  genus  Ncmestrina  the  palpi  are 
of  three  segments. 


456  DIPTERA  CHAP. 

a  natural  group,  but  the  association  with  them  of  the  other 
families  mentioned  is  a  mere  temporary  device.  The  greatest 
difficulty  is  experienced  in  deciding  on  a  position  for  Phoridae,  as 
to  which  scarcely  any  two  authorities  are  agreed. 

Series  4.  Cijclorrhapha,  Schizophora,  or  Eumyiid  flies.  The  antennae  consist 
of  three  joints  and  an  arista.  In  the  Calyptratae  the  frontal  suture, 
or  fold  over  the  antennae,  is  well  marked  and  extends  downwards 
along  each  side  of  the  face,  leaving  a  distinct  lunule  over  the 
antennae.  In  the  Acalyptrate  Muscids  the  form  of  the  head  and 
of  the  antennae  vary  much  and  are  less  characteristic,  but  the 
wings  differ  from  those  of  Brachycera  by  their  much  less  complex 
nervuration. 

Series  5.  Pupipara.  These  are  flies  of  abnormal  habits,  and  only  found  in 
connection  with  living  Vertebrates,  of  which  they  suck  the  blood 
(one  species,  Braula  caeca,  lives  on  bees).  Many  are  wingless, 
or  have  wings  reduced  in  size.  The  young  are  produced  alive, 
lull  grown,  but  having  still  to  undergo  a  metamorphosis.  This 
group  consists  of  a  small  number  of  flies  of  which  some  are 
amongst  the  most  aberrant  known.  This  is  specially  the  case  with 
the  Nycteribiidae.  This  Section  will  probably  be  greatly  modified, 
as  it  is  far  from  being  a  natural  assemblage.1 

The  Sub-Order  Aphaniptera,  or  Fleas,  considered  a  distinct  Order  by  many 
entomologists,  may  for  the  present  be  placed  as  a  part  of  Diptera. 

It  must  be  admitted  that  these  sections  are  far  from  satis- 
factory. Brauer  divides  them  into  Tribes,  based  on  the  nature 
of  the  larvae,  but  these  tribes  are  even  more  unsatisfactory  than 
the  sections,  hosts  of  species  being  entirely  unknown  in  the 
larval  state,  and  many  of  those  that  are  known  having  been  very 
inadequately  studied.  "We  must  admit  that  the  classification  of 
Diptera  has  at  present  advanced  but  little  beyond  the  stage  of 
arranging  them  in  natural  families  capable  of  exact  definition. 
We  may,  however,  draw  attention  to  the  attempt  that  is  being 
made  by  Osten  Sacken  to  remodel  the  classification  of  the  Nemo- 
cera  and  Brachycera  by  the  combination  of  families  into  super- 
families.2  He  proposes  to  divide  the  Nemocera  into  two  super- 
families  :  1.  Nemocera  Vera,  including  all  the  families  from 
Cecidomyiidae  to  Tipulidae ;  2.  Nemocera  Aiiomala,  consisting  of 
the  small  families  Bibionidae,  Simuliidae,  Blepharoceridae,  Ehy- 
phidae  and  Orphnephilidae. 

For  Orthorrhapha  Brachycera  he  adopts  the  following  arrange- 

1  For  tables  of  the  families  of  flies  the  student  may  refer  to  Loe\v,  Smithson- 
Misc.   Cull   vi.    Art.    i.    1862  ;    to   Brauer,  Dcnk.  Al:    Jl'icn,    xlii.    1880,    p.    110 
(Orthorrhapha  only)  ;    to  Williston,  Manual  of  N.  American  Diptera,   1896  ;    to 
Schiner,  Fauna  austriaca,  Diptera,  Vienna,  1860,  etc. 

2  Berlin,  cnt.  Zcitschr.  xxxvii.  1892,  p.  365,  and  xli.  1897,  p.  365. 


vii  BLOOD-SUCKING    FLIES  457 

me nt :  1.  Super- family  Eremochaeta,  for  Stratiomyidae,  Tabanidae, 
Acanthomeridae  and  Leptidae  ;  2.  Tromoptera,  for  Nemestrinidae, 
Acroceridae,  Bombyliidae,  Therevidae,  and  Sceuopinidae  ;  3.  Ener- 
gopoda,  for  Asilidae,  Dolichopidae,  Empidae  and  Lonchopteridae, 
Phoridae  being  included  with  doubt ;  4.  Mydaidae  remains  isolated. 

This  classification  is  based  on  the  relations  of  the  eyes  and 
bristles  of  the  upper  surface,  and  on  the  powers  of  locomotion, 
aerial  or  terrestrial.  At  present  it  is  not  sufficiently  precise  to 
be  of  use  to  any  but  the  very  advanced  student. 

Blood-sucking  Diptera. — The  habit  of  blood-sucking  from 
Vertebrates  is,  among  Insects,  of  course  confined  to  those  with 
suctorial  mouth,  and  is  exhibited  by  various  Diptera.  It  is, 
however,  indulged  in  by  but  a  small  number  of  species,  and 
these  do  not  belong  to  any  special  division  of  the  Order.  It  is 
remarkable  that  as  a  rule  the  habit  is  confined  to  the  female  sex, 
and  that  a  large  proportion  of  the  species  have  aquatic  larvae. 
This  subject  has  many  points  of  interest,  but  does  not  appear  to 
have  yet  received  the  attention  it  merits.  We  give  below  a 
brief  summary  of  the  facts  as  to  blood-sucking  Diptera. 

Series  I.  Nemocera. — In  this  section  the  habit  occurs  in  no  less 
than  five  families,  viz.  : 

Blepharoceridae.      Curupira  ;  in  the  female  only  ;  larva  aquatic. 

Culicidae.  Culex,  Mosquitoes ;  in  the  female  only ;  other 
genera,  with  one  or  two  exceptions,  do  not  suck  blood ; 
larvae  aquatic. 

Chironomidae.  Ceratopogon,  Midge  ;  in  the  female  only ;  ex- 
ceptional even  in  the  genus,  though  the  habit  is  said  to 
exist  in  one  or  two  less  known,  allied  genera ;  larval  habits 
not  certain  ;  often  aquatic ;  in  C.  bipunctatus  the  larva  lives 
under  moist  bark. 

Psychodidae.  Pklebotomus :  in  the  female  only  (?) ;  quite  ex- 
ceptional in  the  family ;  larva  aquatic  or  in  liquid  filth. 

Simuliidae.    Simulium,  sand- flies;    general  in  the  family  (?), 

which,  however,  is   a  very  small   one  ;  larva   aquatic,  food 

probably  mixed  vegetable  and  animal  microscopic  organisms. 

Series  II.  Brachycera.     Tabanidae.     Gad-flies  :  apparently  general 

in  the  females  of  this  family ;   the  habits  of  the   exotic  forms 

but  little  known  ;   in   the   larval  state,  scarcely  at   all  known  ; 

some  are  aquatic, 


458  DIPTERA  CHAP. 

Series  IV.  Cyclorrhapha  Schizophora :  Stomoxys,  Haematobia  ; 
both  sexes  (?) ;  larvae  in  dung.  [The  Tse-tse  flies,  Glossina, 
are  placed  in  this  family,  though  their  mode  of  parturition  is 
that  of  the  next  section]. 

Series  V.  Fupipara.  The  habit  of  blood-sucking  is  probably 
common  to  all  the  group  and  to  both  sexes.  The  flies,  with 
one  exception,  frequent  Vertebrates ;  in  many  cases  living 
entirely  on  their  bodies,  and  apparently  imbibing  much  1  >lood  ; 
the  larvae  are  nourished  inside  the  flies,  not  on  the  imbibed 
blood,  but  on  a  milky  secretion  from  the  mother. 

Sub-Order  Aphaniptera.  Fleas.  The  habit  of  blood-sucking  is 
common  to  all  the  members  and  to  both  sexes.  The  larvae 
live  on  dried  animal  matter. 

Fossil  Diptera. — A  considerable  variety  of  forms  have  been 
found  in  amber,  and  many  in  the  tertiary  beds  ;  very  few  members 
of  the  Cyclorrhaphous  Sections  are,  however,  among  them ;,  the 
Tipulidae,  on  the  other  hand,  are  richly  represented.  In  the 
Mesozoic  epoch  the  Order  is  found  as  early  as  the  Lias,  the 
forms  being  exclusively  Orthorrhaphous,  both  JSTemocera  and 
Brachycera  being  represented.  All  are  referred  to  existing 
families.  Nothing  has  been  found  tending  to  connect  the 
Diptera  with  other  Orders.  Xo  Palaeozoic  Diptera  are  known. 

Series  L   Orthorrhapha  Nemocera 

Fam.  1.  Cecidomyiidae. — An  extensive  family  of  very  minute 
and  fragile  flics,  the  icings  of  which  hare  r cry  few  nervures ;  the 
antennae  are  rather  long,  and  arc  furnished  with  whorls  of  hair. 
In  the  case  of  some  species  the  antennae  are  beautiful  objects ; 
in  Xylodiplosis  some  of  the  hairs  have  no  free  extremities,  but 
form  loops  (Fig.  220).  In  the  males  of  certain  species  the 
joints  appear  to  be  double,  each  one  consisting  of  a  neck  and  a 
body.  Although  comparatively  little  is  known  as  to  the  flies 
themselves,  yet  these  Insects  are  of  importance  on  account  of 
their  preparatory  stages.  The  larvae  have  very  diverse  habits ; 
the  majority  live  in  plants  and  form  galls,  or  produce  defor- 
mations of  the  leaves,  flowers,  stems,  buds,  or  roots  in  a  great 
variety  of  ways ;  others  live  under  bark  or  in  animal  matter ; 
some  are  predaceous,  killing  Aphidae  or  Acari,  and  even  other 


VII 


CECIDOMYIIDAE 


459 


Cecidomyiids.  The  Xorth  American  Diplosis  resinicola  lives  in 
the  resin  exuded  as  the  results  of  the  attacks  of  a  caterpillar. 
The  larva  burrows  in  the  semi-liquid  resin,  and,  according  to 
Osten  Sacken,1  is  probably  ampliipneustic.  Cecidomyiid  larvae 
are  short  maggots,  narrowed  at  the  t\vo  ends,  with  a  very  small 
head,  and  between  this  and  the  first  thoracic  segment  (this  bears  a 
stigma),  a  small  supplementary  segment ;  the  total  number  of  seg- 
ments is  thirteen,  besides  the  head;  there  are  eight  pairs  of  stigmata 


FIG.  219. — Cecidomyia  (Diplosis)  buxi. 
Britain.  A,  Larva,  magnified  ;  B, 
pupa  ;  C,  imago  ;  D,  portion  of  an- 
tenna. (After  Laboulbeue.) 


FIG.  220. — One  segment  of  an- 
tenna of  Xylodiplosis  sp.  ;  «, 
Tip  of  one  segment  ;  b,  base  of 
another.  (After  Janet.) 


on  the  posterior  part  of  the  body.  Brauer  defines  the  Cecido- 
myiid larva  thus,  "  peripneustic,  with  nine  pairs  of  stigmata,  the 
first  on  the  second  segment  behind  the  head  ;  two  to  nine  on  fifth 
to  twelfth  segments ;  body  as  a  whole  fourteen  -  segmented 
without  a  fully-formed  head."  The  most  remarkable  peculiarity 
of  Cecidomyiid  larvae  is  that  those  of  many  species  possess  a 
peculiar  organ — called  breast-bone,  sternal  spatula,  or  anchor- 
process — projecting  from  the  back  of  the  lower  face  of  the  pro- 
thoracic  segment.  The  use  of  so  peculiar  a  structure  has  been 
much  discussed.  According  to  Giard,-  in  addition  to  the  part 

1   Tr.  Amcr.  cut.  Soc.  iii.  1871,  p.  345.  ~  Bull.  Soc.  cnt.  France,  1893,  p.  Ixxx. 


460  DIPTERA  CHAP. 

that  protrudes  externally,  as  shown  in  Fig.  219,  A,  there  is  a  longer 
portion  concealed,  forming  a  sort  of  handle,  having  muscles 
attached  to  it.  Some  of  these  larvae  have  the  power  of  executing 
leaps,  and  he  states  that  such  larvae  are  provided  on  the  terminal 
segment  with  a  pair  of  corneous  papillae ;  bending  itself  almost 
into  a  circle,  the  larva  hooks  together  the  breast-hone  and 
the  papillae,  and  when  this  connection  is  broken  the  spring 
occurs.  This  faculty  is  only  possessed  by  a  few  species,  and  it 
is  probable  that  in  other  cases  the  spatula  is  used  as  a  means  fur 
changing  the  position  or  as  a  perforator.  Some  of  the  larvae 
possess  false  feet  on  certain  of  the  segments.  Williston  says 
they  probably  do  not  moult.  In  the  pupal  instar  (Fig.  219,  B),  the 
Cecidomyiid  greatly  resembles  a  minute  Lepidopterous  pupa. 
The  Hessian  fly,  Cecidomyia  destructor,  is  frecpiently  extremely 
injurious  to  crops  of  cereals,  and  in  some  parts  of  the  world 
commits  serious  depredation.  The  larva  is  lodged  at  the  point 
where  a  leaf  enwraps  the  stem ;  it  produces  a  weakness  of  the 
stem,  which  consequently  bends.  This  Insect  and  C.  tritici  (the 
larva  of  which  attacks  the  flowers  of  wheat)  pupate  in  a  very 
curious  manner :  they  form  little  compact  cases  like  flax-seeds ; 
these  have  been  supposed  to  be  a  form  of  pupa  similar  to  what 
occurs  in  the  Blow-fly  ;  but  there  are  important  distinctions.  The 
larva,  when  about  to  undergo  its  change,  exudes  a  substance  from 
its  skin,  and  this  makes  the  flax-seed  ;  the  larval  skin  itself  does 
not  form  part  of  this  curious  kind  of  cocoon,  for  it  may  be  found, 
as  well  as  the  pupa,  in  the  interior  of  the  "  flax-seed."  Other 
Cecidomyiids  form  cocoons  of  a  more  ordinary  kind ;  one  species, 
described  by  Ferris  as  living  on  Finns  iiiariti m«,  has  the  very 
remarkable  faculty  of  surrounding  itself,  by  some  means,  with  a 
cocoon  of  resin.  Walsh  describes  the  cocoon-forming  process  of 
certain  Cecidomyiids  as  one  of  exudation  and  inflation  ;  Willistoii 
as  somewhat  of  the  nature  of  crystallisation.  Some  Cecidomyiids 
are  said  to  possess,  in  common  with  certain  other  Diptera,  the 
unusual  number  of  five  Malpighian  tubes ;  and  Giard  says  that 
in  the  larva  there  is  only  a  pair  of  these  tubes,  and  that  their 
extremities  are  united  so  as  to  form  a  single  'tube,  which  is 
twisted  into  an  elegant  double  loop. 

Thirty  years  or  more  ago  the  L'ussian  naturalist,  Wagner, made 
the  very  remarkable  discovery  that  the  larva  of  a  Cecidomyiid 
produces  young ;  and  it  has  since  been  found  by  Meinert  and 


VII 


CECIDOMYIIDAE  46 1 


others  that  this  kind  of  paedogenesis  occurs  in  several  species  of 
the  genera  Miastor  and  Oliyarces.  The  details  are  briefly  as 
follows  : — A  female  fly  lays  a  few,  very  large,  eggs,  out  of 
each  of  which  comes  a  larva,  that  does  not  go  on  to  the 
perfect  state,  but  produces  in  its  interior  young  larvae  that, 
after  consuming  the  interior  of  the  Lody  of  the  parent  larva, 
escape  Toy  making  a  hole  in  the  skin,  and  thereafter  subsist 
externally  in  a  natural  manner.  This  larval  reproduction  may 
be  continued  for  several  generations,  through  autumn,  winter, 
and  spring  till  the  following  summer,  when  a  generation  of  the 
larvae  goes  on  to  pupation  and  the  mature,  sexually  perfect  fly 
appears.  Much  discussion  has  taken  place  as  to  the  mode 
of  origination  of  the  larvae ;  Carus  and  others  thought  they 
were  produced  from  the  rudimental,  or  immature  ovaries  of  the 
parent  larva.  Meinert,  who  has  made  a  special  study  of  the 
subject,1  finds,  however,  that  this  is  not  the  case  ;  in  the  repro- 
ducing larva  of  the  autumn  there  is  no  ovary  at  all ;  in  the  re- 
producing larvae  of  the  spring-time  rudimentary  ovaries  or  testes, 
as  the  case  may  be,  exist  ;  the  young  are  not,  however,  produced 
from  these,  but  from  germs  in  close  connection  with  the  fat- 
body.  In  the  larvae  that  go  on  to  metamorphosis  the  ovaries 
continue  their  natural  development.  It  would  thus  appear  that 
the  fat-body  has,  like  the  leaf  of  a  Begonia,  under  certain  circum- 
stances, the  power,  usually  limited  to  the  ovaries,  of  producing 
complete  and  perfect  individuals. 

Owing  to  the  minute  size  and  excessive  fragility  of  the  Gall- 
midge  flies  it  is  extremely  difficult  to  form  a  collection  of  them  ; 
and  as  the  larvae  are  also  very  difficult  of  preservation,  nearly 
every  species  must  have  its  life-history  worked  out  as  a  special 
study  before  the  name  of  the  species  can  be  ascertained.  Not- 
withstanding the  arduous  nature  of  the  subject  it  is,  however,  a 
favourite  one  with  entomologists.  The  number  of  described  and 
named  forms  cannot  be  very  far  short  of  1000,  and  each  year  sees 
some  20  or  30  species  added  to  the  list.  The  number  of  unde- 
scribed  forms  is  doubtless  very  large.  The  literature  of  the  subject 
is  extensive  and  of  the  most  scattered  and  fragmentary  character. 

The  Cecidomyiidae  have  but  little  relation  to  other  Nemocera, 
and  are  sometimes  called  Oligoneura,  on  account  of  the  reduced 
number  of  wing-nervures.  Their  larvae  are  of  a  peculiar  type 
1  Naturhist.  Tidskr.  (3)  viii.  1874,  p.  34,  pi.  xii. 


462 


DIPTERA 


CHAP. 


that  does  not  agree  with  the  larvae  of  the  allied  families  having 

o  o 

well-marked  heads  (and  therefore  called  Eucephala),  nor  with  the 
acephalous  maggots  of  Eumyiidae. 

Fam.  2.  Mycetophilidae. — These  small  flics  are  much  less 
delicate  creatures  than  the  Cccidomyiidae,  and  have  more  nervures 
in  the  winys  ;  they  possess  ocelli,  and  frequently  have  the  coxae 
elongated,  mid  in  some  cases  the  A'//x  adorned  with  comj>ft*,r  arrange- 
ments of  spines  :  their  antennae  hacc  not  whorls  of  hair.  Although 
very  much  neglected  there  are  probably  between  700  and  1000 
species  known ;  owing  to  many  of  their  larvae  living  in  fungoid 
matter  the  flies  are  called  Fungus-gnats.  We  have  more  than 
100  species  in  Britain.  Epidapus  is  remarkable,  inasmuch  as 
the  female  is  entirely  destitute  of  wings  and  halteres,  while 

the  male  has  the  halteres 
developed  but  the  wings  of 
very  reduced  size.  E.  scabiei 
is  an  excessively  minute  fly, 
smaller  than  a  common  flea, 
and  its  larva  is  said  to  be 
very  imjurious  to  stored 
potatoes.  The  larvae  of 
Mycetophilidae  are  usually 
very  elongate,  worm  -  like 
maggots,  but  have  a  distinct, 
FiQ.221.—Mycetobiapallipee.  Britain.  small  head;  they  are  pe'ri- 

A,  Larva;    B,  pupa;  C,  imago.      (After  Dufour.)  ,.     -,        .  -,  • 

pneustic,  having, according  to 

Osten  Sacken,  nine  pairs  of  spiracles,  one  pair  prothoracic,  the  others 
on  the  first  eight  abdominal  segments.  They  are  usually  worm- 
like,  and  sometimes  seem  to  consist  of  twenty  segments.  Some  of 
them  have  the  facility  of  constructing  a  true  cocoon  by  some  sort 
of  spinning  process,  and  a  few  make  earthen  cases  for  the  purpose  of 
pupation.  The  pupae  themselves  are  free,  the  larval  skin  having 
been  shed.  The  Mycetophilidae  are  by  no  means  completely 
fungivorous,  for  many  live  in  decaying  vegetable,  some  even  in 
animal,  matter. 

The  habits  of  many  of  the  larvae  are  very  peculiar,  owing  to 
their  spinning  or  exuding  a  mucus,  that  reminds  one  of  snail- 
slime  ;  they  are  frequently  gregarious,  and  some  of  them  have 
likewise,  as  \ve  shall  subsequently  mention,  migratory  habits. 
Perris  has  deseribed  the  very  curious  manner  in  which  Sciophila 


VII 


MYCETOPHILIDAE  463 


unimaculata  forms  its  slimy  tracks ; l  it  stretches  its  head  to  one 
side,  fixes  the  tip  of  a  drop  of  the  viscous  matter  from  its 
mouth  to  the  surface  of  the  substance  over  which  it  is  to 
progress,  bends  its  head  under  itself  so  as  to  affix  the  matter  to 
the  lower  face  of  its  own  body ;  then  stretches  its  head  to  the 
other  side  and  repeats  the  operation,  thus  forming  a  track  on 
which  it  glides,  or  perhaps,  as  the  mucus  completely  envelops 
its  body,  we  should  rather  call  it  a  tunnel  through  which  the 
maggot  slips  along.  According  to  the  description  of  Hudson 2 
the  so-called  New  Zealand  Glow-worm  is  the  larva  of  Boleto- 
pliila  luminosa ;  it  forms  webs  in  dark  ravines,  along  which  it 
glides,  giving  a  considerable  amount  of  light  from  the  peculiarly 
formed  terminal  segment  of  the  body.  This  larva  is  figured  as 
consisting  of  about  twenty  segments.  The  pupa  is  provided 
with  a  very  long,  curiously-branched  dorsal  structure :  the  fly 
issuing  from  the  pupa  is  strongly  luminous,  though  no  use  can 
be  discovered  for  the  property  either  in  it  or  in  the  larva.  The 
larva  of  the  Australian  Geroplatus  master  si  is  also  luminous. 
Another  very  exceptional  larva  is  that  of  Epicypta  scatopliora ; 
it  is  of  short,  thick  form,  like  Cecidomyiid  larvae,  and  has  a  very 
remarkable  structure  of  the  dorsal  parts  of  the  body ;  by  means  of 
this  its  excrement,  which  is  of  a  peculiar  nature,  is  spread  out  and 
forms  a  case  for  enveloping  and  sheltering  the  larva.  Ultimately 
the  larval  case  is  converted  into  a  cocoon  for  pupation.  This  larva 
is  so  different  from  that  of  other  Mycetophilidae,  that  Perils  \vas 
at  first  unable  to  believe  that  the  fly  he  reared  really  came  from 
this  unusually  formed  larva.  The  larva  of  Mycetobici  pallipes 
(Fig.  221)  offers  a  still  more  remarkable  phenomenon,  inasmuch 
as  it  is  amphipneustic  instead  of  peripneustic  (that  is  to  say,  it 
has  a  pair  of  stigmata  at  the  termination  of  the  body  and  a  pair 
on  the  first  thoracic  segment  instead  of  the  lateral  series  of  pairs 
we  have  described  as  normal  in  Mycetophilidae).  This  larva  lives 
in  company  with  the  amphipneustic  larva  of  Rliy pirns,  a  fly  of 
quite  another  family,  and  the  Mycetolia  larva  so  closely  resembles 
that  of  the  Rhyphus,  that  it  is  difficult  to  distinguish  the  two. 
This  anomalous  larva  gives  rise,  like  the  exceptional  larva  of 
Epicypta,  to  an  ordinary  Mycetophilid  fly.3 

1  Ann.  Soc.  cnt.  France  (2)  vii.  1849,  p.  346. 

2  Trans.  Neio  Zealand  Inst.  xxiii.  1890,  p.  48. 

3  Osten  Sacken,  Berlin.  cnt.Zcitschr.  xxxvii.  1892,  p.  442;  and  Ferris,  Ann.  Soc. 
cnt.  France  (2)  vii.  1849,  p.  202. 


464  DIPTERA 


CHAP. 


But  the  most  remarkable  of  all  the  Mycetophilid  larvae  are 
those  of  certain  species  of  Sciara,  that  migrate  in  columns,  called 
by  the  Germans,  Heerwurm.  The  larva  of  Sciara  militaris 
lives  under  layers  of  decomposing  leaves  in  forests,  and  under 
certain  circumstances,  migrates,  sometimes  perhaps  in  search  of  a 
fresh  supply  of  food,  though  in  some  cases  it  is  said  this  cannot  be 
the  reason.  Millions  of  the  larvae  accumulate  and  form  them- 
selves by  the  aid  of  their  viscous  mucus  into  great  strings  or 
ribbons,  and  then  glide  along  like  serpents  :  these  aggregates  are 
said  to  be  sometimes  forty  to  a  hundred  feet  long,  five  or  six  inches 
wide,  and  an  inch  in  depth.  It  is  said  that  if  the  two  ends  of 
one  of  these  processions  be  brought  into  contact,  they  become 
joined,  and  the  monstrous  ring  may  writhe  for  many  hours  before 
it  can  again  disengage  itself  and  assume  a  columnar  form. 
These  processional  maggots  are  met  with  in  Northern  Europe 
and  the  United  States,  and  there  is  now  an  extensive  literature 
about  them.1  Though  they  sometimes  consist  of  almost  incredible 
numbers  of  individuals,  yet  it  appears  that  in  the  Carpathian 
mountains  the  assemblages  are  usually  much  smaller,  being  from 
four  to  twenty  inches  long.  A  species  of  Sciara  is  the  "Yellow- 
fever  fly "  of  the  Southern  United  States.  It  appears  that  it 
In  is  several  times  appeared  in  unusual  numbers  and  in  unwonted 
localities  at  the  same  time  as  the  dreaded  disease,  with  which  it 
is  popularly  supposed  to  have  some  connection. 

Fam.  3.  Blepharoceridae.'2-  -7n////.s  with  )/<>  Jiscal  cell,  lut 
with  a  xcrtniiliu-i/  set  of  creasc-Ukc  line*.  The  flies  composing 
this  small  family  are  very  little  known,  and  appear  to  be 
obscure  Insects  with  somewhat  the  appearance  of  Empidae, 
t bough  with  strongly  iridescent  wings;  they  execute  aerial 
dances,  after  the  manner  of  midges,  and  are  found  in  Europe 
(the  Pyrenees,  Alps  and  Harz  mountains)  as  well  as  in  North 
;nid  South  America.  Their  larvae  are  amongst  the  most  re- 

O 

luarkable   of  Insect   forms;    indeed,    no    entomologist   recognises 
them  as  belonging  to  a  Hexapod   Insect   when   he  makes   a   first 


1  See  Guerin-Meiievilie.  Ann.  Soc.  nil.  Prune,  <2)  iv.  1840  ;  LnU.  p.  8  ;  and 
i,  Verh.  <!<s.  //'/<•//.,  xvii.  1867,  /S7?.  p.  23. 

-'  For  details  as  tn  the  family  of.  Ostcii  .Sacken,  Hcrlin.  cut.  Zcitschr.  xl. 
1895,  ]..  148;  and  for  the  larvae  F.  Muller,  Arch.  Mas.  Rio-Jan,  iv.  1881, 
p.  47.  The  name  "  Lipnneuridae "  was  formerly  applied  liy  some  authorities 
to  ihis  family,  l.ut  it  is  now  generally  recognised  that  Blepharoceridae  is  more 
legil  imati 


VI 1 


BLEPHAROCERIDAE 


465 


acquaintance  with  them.  The  larva  of  Cuvupira  (Fig.  222) 
lives  in  rapid  streams  in  Brazil,  fixed  by  its  suckers  to  stones  or 
rocks.  It  consists  only  of  six  or  seven  divisions,  with  project- 
ing side-lobes ;  the  usual  segmentation  not  being  visible.  There 
are  small  tracheal  gills  near  the  suckers,  and  peculiar  scale-like 
organs  are  placed  about  the  edges  of  the  lobes.  Miiller  considers 
that  the  first  lobe  is  "  cephalothorax,"  corresponding  to  head, 
thorax  and  first  abdominal  segment  of  other  larvae,  the  next  four 
lobes  he  considers  to  correspond  each  to  an 
abdominal  segment,  and  the  terminal  mass 
to  four  segments.  He  also  says  that 
certain  minute  points  existing  on  the  sur- 
face, connected  with  the  tracheal  system  by 
minute  strings,  represent  nine  pairs  of 
spiracles.  These  larvae  and  their  pupae 
can  apparently  live  only  a  short  time  after 
being  taken  out  of  the  highly  aerated 
water  in  which  they  exist,  but  Miiller 
succeeded  in  rearing  several  flies  from  a 
number  of  larvae  and  pupae  that  he 
collected,  and,  believing  them  to  be  all  one 
species,  he  announced  that  the  females 
exhibited  a  highly  developed  dimorphism, 
some  of  them  being  blood-suckers,  others 
honey-suckers.  It  is  however,  more  prob- 
able that  these  specimens  belonged  to  two  . 

Fir;.  222. — Under  surface  of 

or  three  distinct  species  or  even  genera. 
This  point  remains  to  be  cleared  up.  The 
larva  we  have  figured  is  called  by  Miiller 
Paltostoma  torrentium.  It  is  certain,  how- 
ever, that  the  Brazilian  Insect  does  not 
belong  to  the  genus  Paltostoma,  and  it  will  no  doubt  bear  the 
name  used  by  Osten  Sacken,  viz.  Curupira. 

The  metamorphoses  of  the  European  Liponeura  Irevirostris 
have  been  partially  examined  by  Dewitz,  who  found  the  Insects 
in  the  valley  of  the  Ocker  in  September.1  He  does  not  consider 
the  "  cephalothorax  "  to  include  an  abdominal  segment ;  and  he 
found  that  two  little,  horn-like  projections  from  the  thorax  of  the 

1  BcrUn.   <•  nt.  Zcit.  xxv.  1881,  p.    61  ;  and  cf.  Brauer,  JJ'-icn.  ent.  Zcit.   i.  1882, 
p.  1. 

VOL.  VI  2   H 


the  larva  of  Cuni/>if<i. 
(Paltostoma)  torrentium , 
showing  the  suckers  along 
the  middle  of  the  body, 
much  magnified.  Brazil. 
(After  Fritz  Miiller.) 


466  DIPTERA 


CHAP. 


pupa  are  really  each  four-leaved.  The  pupa  is  formed  within 
the  larval  skin,  but  the  latter  is  subsequently  cast  so  that  the 
pupa  is  exposed  ;  its  dorsal  region  is  horny,  but  the  under  sur- 
face, by  which  it  clings  firmly  to  the  stones  of  the  rapid  brook,  is 
white  and  scarcely  chitinised,  and  Dewitz  considers  that  the 
chitinous  exudation  from  this  part  is  used  as  a  means  of  fastening 
the  pupa  to  the  stones.  Blepharoceridae  possess,  in  common 
with  Culex,  Psychoda  and  Ptychoptera,  the  peculiar  number  of 
five  Malpighian  tubes,  and  it  has  been  proposed  by  Miiller  to 
form  these  Insects  into  a  group  called  Pentanephria. 

Fam.  4.  Culicidae  (Mosquitoes,  Gnats). — Antennae  with  whorls 
of  hair  or  plumes,  which  may  be  very  dense  and  long  in  the  male, 
.though  scanty  in  the  female  ;  head  with  a  long,  projecting  pro- 
boscis. Although  there  are  few  Insects  more  often  referred  to 
in  general  literature  than  Mosquitoes,  yet  the  ideas  in  vogue 
about  them  are  of  the  vaguest  character.  The  following  are  the 
chief  points  to  be  borne  in  mind  as  to  the  prevalence  of  Mos- 
quitoes : — The  gently  humming  Gnat  that  settles  on  us  in  our 
apartments,  and  then  bites  us,  is  a  Mosquito  ;  there  are  a  large 
number  of  species  of  Mosquitoes  ;  in  some  countries  many  in  one 
locality  ;  in  -Britain  we  have  ten  or  a  dozen  ;  notwithstanding  the 
multiplicity  of  species,  certain  Mosquitoes  are  very  widely  diffused  ; 
the  larvae  are  all  aquatic,  and  specially  frequent  stagnant  or 
quiet  pools ;  they  are  probably  diffused  by  means  of  the  water 
in  ships,  it  being  known  that  Mosquitoes  were  introduced  for 
the  first  time  to  the  Hawaiian  Islands  by  a  sailing  vessel  about 
the  year  1828.  Hence  it  is  impossible  to  say  what  species  the 
Mosquitoes  of  a  given  locality  may  be  without  a  critical  examina- 
tion. No  satisfactory  work  on  the  Mosquitoes  of  the  world 
exists.  Urich  states  that  he  is  acquainted  with  at  least  ten 
species  in  Trinidad.  The  species  common  in  our  apartments  in 
Central  and  Southern  England  is  Culex  pipiens,  Linn.,  and  this 
species  is  very  widely  distributed,  being  indeed  one  of  the 
troublesome  Mosquitoes  of  East  India.  The  term  Mosquito  is  a 
Spanish  or  Portuguese  diminutive  of  Mosca.  It  is  applied  to  a 
v.iriety  of  small  flies  of  other  families  than  Culicidae,  but  should 
be  restricted  to  these  latter.  The  irritation  occasioned  by  the 
bites  of  Mosquitoes  varies  according  to  several  circumstances, 
\\y..  tin-  condition  of  the  biter,  the  condition  or  constitution  of 
the  bitten,  and  also  the  species  of  Mosquito.  Reaumur  and 


VII 


MOSQUITOES  467 


others  believed  that  some  irritating  fluid  is  injected  by  the  Mos- 
quito when  it  bites.  But  why  should  it  want  to  irritate  as  well 
as  to  bite  ?  Maclbskie,  considering  that  the  Mosquito  is  really 
a  feeder  on  plant-substances,  suggests  that  the  fluid  injected  may 
be  for  the  purpose  of  preventing  coagulation  of  the  plant-juices 
during  the  process  of  suction.  It  is  a  rule  that  only  the  female 
Mosquito  bites,  the  male  being  an  inoffensive  creature,  and  pro- 
vided with  less  effectual  mouth-organs;  it  has,  however,  been 
stated  by  various  authors  that  male  Mosquitoes  do  occasionally 
bite.  It  is  difficult  to  understand  the  blood-sucking  propensities 
of  these  Insects  ;  we  have  already  stated  that  it  is  only  the 
females  that  suck  blood.  There  is  reason  to  suppose  that  it  is  an 
acquired  habit ;  and  it  would  appear  that  the  food  so  obtained 
is  not  essential  to  their  existence.  It  has  indeed  been  asserted 
that  the  act  is  frequently  attended  with  fatal  consequences  to 
the  individual  that  does  it.  The  proper  method  of  mitigating 
their  nuisance  is  to  examine  the  stagnant  waters  in  localities 
where  they  occur,  and  deal  with  them  so  as  to  destroy  the  larvae. 
These  little  creatures  are  remarkable  from  the  heads  and  thorax 
being  larger  and  more  distinct  than  in  other  Dipterous  larvae. 
Their  metamorphoses  have  been  frequently  described,  and  recently 
the  numerous  interesting  points  connected  with  their  life-histories 
have  been  admirably  portrayed  by  Professor  Miall,1  in  an  accessible 
form,  so  that  it  is  unnecessary  for  us  to  deal  with  them. 
Corethra  is  placed  in  Culicidae,  but  the  larva  differs  totally  from 
that  of  Old  ex ;  it  is  predaceous  in  habits,  is  very  transparent,  has 
only  an  imperfect  tracheal  system,  without  spiracles,  and  has  two 
pairs  of  air-sacs  (perhaps  we  should  rather  say  pigmented  struc- 
tures possibly  for  aerostatic  purposes,  but  not  suppliers  of  oxygen). 
The  kungu  cake  mentioned  by  Livingstone  as  used  on  Lake 
JSTyassa  is  made  from  an  Insect  which  occurs  in  profusion  there, 
and  is  compressed  into  biscuit  form.  It  is  believed  to  be  a 
Corethra.  One  of  the  peculiarities  of  this  family  is  the  pre- 
valence of  scales  on  various  parts  of  the  body,  and  even  on  the 
wings :  the  scales  are  essentially  similar  to  those  of  Lepidoptera. 
Though  Mosquitoes  are  generally  obscure  plain  Insects,  there 
are  some — in  the  South  American  genus  Megarrhina — that  are 
elegant,  beautifully  adorned  creatures.  Swarms  of  various  species 
of  Culicidae.  consisting  sometimes  of  almost  incalculable  numbers 
1  Xatural  History  of  Aquatic  Insects,  London,  1895,  chap.  ii. 


468  DIPTERA  CHAP. 

of  individuals,  occur  in  various  parts  of  the  world ;  one  in  New 
Zealand  is  recorded  as  having  been  three-quarters  of  a  mile  long, 
twenty  feet  high,  and  eighteen  inches  thick.  There  is  good  • 
reason  for  supposing  that  Mosquitoes  may  act  as  disseminators 
of  disease,  but  there  is  no  certain  evidence  on  the  subject.  The 
minute  Filar ia  that  occurs  in  great  numbers  in  some  patients, 
is  found  in  the  human  body  only  in  the  embryonic  and  adult 
conditions.  Maiison  considers  that  the  intermediate  stages  are 
passed  in  the  bodies  of  certain  Mosquitoes.1 

Fam.  5.  Chironomidae  (Gnats,  Midges}. — Small  or  minute 
flies  of  slender  form,  with  narrow  wings,  without  projecting 
rasft'i/ in,  usually  with  densely  feathered  antennae  in  the  male,  and 
long  slender  legs.  The  flies  of  this  family  bear  a  great  general 
resemblance  to  the  Culicidae.  They  are  much  more  numerous 
in  species,  and  it  is  not  improbable  that  we  have  in  this  country 
200  species  of  the  genus  Chironomiis  alone.  They  occur  in 
enormous  numbers,  and  frequently  form  dancing  swarms  in  the 
neighbourhood  of  the  waters  they  live  in.  The  species  are 
frequently  extremely  similar  to  one  another,  though  distinguished 
by  good  characters ;  they  are  numerous  about  Cambridge.  Many 
of  them  have  the  habit  of  using  the  front  legs  as  feelers  rather 
than  as  means  of  support  or  locomotion.  This  is  the  opposite  of 
what  occurs  in  Culicidae,  where  many  of  the  species  have  a  habit 
of  holding  up  the  hind  legs  as  if  they  were  feelers.  The  eggs  of 
Chironomiis  are  deposited  as  strings  surrounded  by  mucus,  and  are 
many  of  them  so  transparent  that  the  development  of  the  embryo 
can  be  directly  observed  with  the  aid  of  the  microscope.  They  are 
said  to  possess  a  pair  of  air-sacs.  The  larvae,  when  born,  are 
aquatic  in  habits,  and  are  destitute  of  trachea!  system.  They 
subsequently  differ  greatly  from  the  larvae  of  Culex,  inasmuch  as 
the  tracheal  system  that  develops  is  quite  closed,  and  in  some 
cases  remains  rudimentary.  There  is,  however,  much  diversity 
in  the  larvae  and  also  in  the  pupae.  The  little  Blood-worms, 
\eiycommon  in  many  stagnant  and  dirty  waters,  and  used  by 
anglers  as  bait,  are  larvae  of  Chironomus.  They  are  said  to  be 
al  'E/iTTtSe?  of  Aristotle.  The  red  colour  of  these  larvae  is  due  to 
haemoglobin,  a  substance  which  lias  the  power  of  attracting  and 
storing  oxygen,  and  giving  it  off  to  the  tissues  as  they  require 
it.  Such  larvae  are  able  to  live  in  burrows  they  construct 

'    Tr.  Linn.  Sue.  Lond.  (2)  ii.  LSS-1,  p.  3t>". 


vii  GNATS MIDGES  469 

amongst  the  mud.  Some  of  them,  provided  plentifully  with 
haemoglobin,  are  in  consequence  able  to  live  at  great  depths,  it 
is  said  even  at  1000  feet  in  Lake  Superior,  and  come  to  the 
surface  only  occasionally.  A  few  are  able  even  to  tolerate  salt 
water,  and  have  been  fished  up  from  considerable  depths  in  the 
sea.  It  is  a  remarkable  fact  that  these  physiological  capacities 
differ  greatly  within  the  limits  of  the  one  genus,  Chironomus, 
for  some  of  these  species  are  destitute  of  haemoglobin,  and  .have 
to  live  near  the  surface  of  the  water ;  these  have  a  superior 
development  of  the  trachea!  system.  The  pupae  of  Chironoinns 
have  the  legs  coiled,  and  the  thorax,  instead  of  being  provided 
with  the  pair  of  tubes  or  trumpets  for  breathing  that  is  so 
common  in  this  division  of  Diptera,  have  a  pair  of  large  tufts 
of  hair-like  filaments.1  A  very  curious  form  of  parthenogenesis 
has  been  described  by  Grimm  2  as  existing  in  an  undetermined 
species  of  Chironomus,  inasmuch  as  the  pupa  deposits  eggs. 
Although  this  form  of  parthenogenesis  is  of  much  interest,  it  is1 
not  in  any  way  to  be  compared  with  the  case,  already  referred  to, 
of  Miastor  (p.  4  6 1 ).  The  "  pupa  "  is  at  the  time  of  oviposition  prac- 
tically the  imago  still  covered  by  the  pupal  integument ;  indeed 
Grimm  informs  us  that  in  some  cases,  after  depositing  a  small 
number  of  ova,  the  pupa  became  an  imago.  This  partheno- 
genesis only  occurs  in  the  spring-generation  ;  in  the  autumn  the 
development  goes  on  in  the  natural  manner.  The  case  is 
scarcely  entitled  to  be  considered  as  one  of  paedogenesis. 

Gnats  of  this  family,  and  believed  to  be  a  variety  of  Chiro- 
nomus phimosus,  are  subject  to  a  curious  condition,  inasmuch  as 
individuals  sometimes  become  luminous  or  "  phosphorescent "  ;  this 
has  been  noticed  more  specially  in  Eastern  Europe  and  Western 
Asia.  The  whole  of  the  body  and  legs  may  exhibit  the  -luminous 
condition,  but  not  the  wings.  It  has  been  suggested  by  Schmidt 
that  this  condition  is  a  disease  due  to  bacteria  in  the  body  of 
the  gnat.3 

Ceratopoyon  is  a  very  extensive  genus,  and  is  to  some 
extent  anomalous  as  a  member  of  Chironomidae.  The  larvae 
exhibit  considerable  variety  of  form.  Some  of  them  are  aquatic 

1  For  an  extremely  interesting  account  of  Chironomus  refer  to  Miall's  book, 
already  cited,  and,  for  the  larva,  to  the  valuable  work  of  Meinert  on  Eucephalous 
larvae  of  Diptera,  DansJce  Sclsk.  Skr.  (6)  iii.  1886,  p.  436. 

"  Ann.  Nat.  Hist.  (4)  viii.  1871,  p.  31.  3  Ibid.  (6)  xv.  1895,  p.  133. 


4/0  DIPTERA  CHAP. 

in  habits,  but  the  great  majority  are  terrestrial,  frequenting 
trees,  etc.  The  former  larvae  are  very  slender,  and  move  after 
the  manner  of  leeches ;  they  give  rise  to  imagos  with  naked 
wings,  while  the  terrestrial  larvae  produce  flies  with  hairy 
wings.  There  are  also  important  distinctions  in  the  pupae  of 
the  two  kinds ;  the  correlation  between  the  habits,  and  the  dis- 
tinctions above  referred  to,  is,  however,  far  from  being  absolutely 
constant.1  Certain  species  of  midges  are  in  this  country  amongst 
11  ic  most  annoying  of  Insects  ;  being  of  very  minute  size,  scarcely 
visible,  they  settle  on  the  exposed  parts  of  the  body  in  great 
numbers,  and  by  sucking  blood  create  an  intolerable  irritation. 
Cerat.»i>ngoit.  mi' ins  is  one  of  the  most  persistent  of  these  arm  overs 
in  Scotland,  where  this  form  of  pest  is  much  worse  than  it  is  in 
England  ;  in  Cambridgeshire,  according  to  Mr.  G.  H.  Yerrall, 
the  two  troublesome  midges  are  the  females  of  C.  puliearis  and 
0.  bipunctatus. 

Fam.  6.  Orphnephilidae. — Xmall,  brown  or  yellowish  flies, 
la  re  of  pubescence,  with  very  large  eyes  contiguous  in  loth  sexes, 
and  with  antennae  composed  of  two  joints  and  a  terminal  bristle  ; 
loth  the  second  joint  and  the  bristle  are,  however,  really  complex. 
One  of  the  smallest  and  least  known  of  the  families  of  Diptera, 
and  said  to  be  one  of  the  most  difficult  to  classify.  The  nervures 
of  the  wings  are  very  distinct.  Nothing  is  known  of  the  habits 
and  metamorphoses ;  there  is  only  one  genus — Orphnephila  ;  it 
is  widely  distributed ;  we  have  one  species  in  Britain. 

Fam.  7.  Psychodidae  (Moth-flies). — Extremely  small,  helpless 
flics,  usinilli/  with  thich'ish  antennae,  hun-ing  much  hair,  with 
wings  Iroade/-  than  is  usual  in  small  flies,  and  also  densely  clothed 
with  hair,  (jiving  rise  to  a  pattern  more  or  less  vague.  These 
flies  are  very  fragile  creatures,  and  are  probably  numerous  in 
species.  In  Britain  forty  or  fifty  species  have  been  recognised.2 
A  South  European  form  is  a  blood-sucker,  and  has  received  the 
appropriate  name  of  Phlebotomus.  The  life-history  of  Ferieoma 
canescens  has  recently  been  studied  by  Professor  Miall.3  The 
l;irv;i  is  of  aquatic  habits,  but  is  amphibious,  being  capable  of 
existing  in  the  air:  it  has  a  pair  of  anterior  spiracles,  by  means 

1  For  metamorphoses  of  aquatic  species  of  Ccralopofjon,  see  Miall  and  Meinert, 
already  <[iio|ril  ;  I'm-  examples  of  tin-  terrestrial  species,  and  their  illustrations, 
refer  to  Mik,  JJ'ii'n..  cut.  Zcit.  vii.  1888,  p.  183. 

-  Monograph,  Eaton,  Enl.  May.  xxix.  and  xxx.  1893,  1894:  supplement  op.  cit. 
1896,  etc.  :!  Tr.  cnt.  Soc.  London,  1895,  p.  141. 


vii  PSYCHODIDAE  -  DIXIDAE--TIPULIDAE 


of  which  it  breathes  in  the  air,  and  a  pair  at  the  posterior 
extremity  of  the  body,  surrounded  by  four  ciliated  processes, 
with  which  it  forms  a  sort  of  cup  for  holding  air  when  it  is 
in  the  water.  The  favourite  position  is  amongst  the  filaments 
of  green  algae  on  which  it  feeds.  A  much  more  extraordinary 
form  of  larva  from  South  America,  doubtless  belonging  to 
this  family,  has  recently  been  portrayed  by  Fritz  Miiller, 
under  the  name  of  Maruina.1.  These  larvae  live  in  rapid  waters 
in  company  with  those  of  the  genus  Curupira,  and  like  the 
latter  are  provided  with  a  series  of  suctorial  ventral  discs. 
Fritz  Miiller's  larvae  belong  to  several  species,  and  probably  to 
more  than  one  genus,  and  the  respiratory  apparatus  at  the 
extremity  of  the  body  exhibits  considerable  diversity  among 
them. 

Fam.  8.  Dixidae.  —  The  genus  Dixa  must,  it  appears,  form  a 
distinct  family  allying  the  Culicid  series  of  families  to  the 
Tipulidae.  The  species  are  small,  gnat-like  Insects,  fond  of 
damp  places  in  forests.  We  have  four  British  species  (I). 
maculata,  D.  nebulosa,  D.  aestivalis,  D.  aprilincf).  The  genus  is 
very  widely  distributed,  occurring  even  in  Australia.  The 
larvae  are  aquatic,  and  have  been  described  by  Reaumur, 
Miall,  and  Meinert.  The  pupa  has  the  legs  coiled  as  in  the 
Culicidae. 

Fam.  9.  Tipulidae  {Daddy-long-legs,  or  Crane-flies').  —  Slender 
Insects  witli  elongate  legs,  a,  system  of  luing-nervures,  rather  com- 
plex, especially  at  the  tip  ;  an  angulate,  or  open  V-shaped,  suture 
on  the  dorsum  of  the  thorax  in  front  of  the  wings  :  the  female 
with  the  l)ody  terminated  l>y  a  pair  of  hard,  pointed  processes, 
concealing  some  other  processes,  and  forming  an  ovipositor.  The 
curious,  silly  Insects  called  daddy-long-legs  are  known  all 
over  the  world,  the  family  being  a  very  large  one,  and  found 
everywhere,  some  of  its  members  extending  their  range  even 
to  the  most  inclement  climates.  It  includes  a  great  variety 
of  forms  that  would  not  be  recognised  by  the  uninitiated, 
but  can  be  readily  distinguished  by  the  characters  mentioned 
above.  It  is  impossible  to  assign  any  reason  of  utility  for 
the  extreme  elongation  of  the  legs  of  these  Insects  ;  as 
everyone  knows,  they  break  off  with  great  ease,  and  the  Insect 
appears  to  get  on  perfectly  well  without  them.  It  is  frequently 

1   Tr.  cnt.  Sue.  London,  1895,  p.  479. 


472  DTPTERA  CHAP. 

the  case  that  they  are  much  longer  in  the  males  than  in 
the  females.  Other  parts  of  the  body  exhibit  a  peculiar 
elongation;  in  some  forms  of  the  male  the  front  of  the  head- 
may  be  prolonged  into  a  rostrum.  In  a  few  species  the 
head  is  separated  by  a  great  distance  from  the  thorax,  the 
gap  being  filled  by  elongate,  hard,  cervical  sclerites ;  indeed 
it  is  in  these  Insects  that  the  phenomenon,  so  rare  in  Insect- 
structure,  of  the  elongation  of  these  sclerites  and  their  be- 
coming a  part  of  the  actual  external  skeleton,  reaches  its 
maximum.  In  several  species  of  Eriocera  the  male  has  the 
antennae  of  extraordinary  length,  four  or  five  times  as  long  as 
the  body,  and,  strange  to  say,  this  elongation  is  accompanied 
by  a  reduction  in  the  number  of  the  segments  of  which  the 
organ  is  composed,  the  number  being  in  the  male  about  six, 
in  the  female  ten,  in  place  of  the  usual  fourteen  or  sixteen. 
In  Tuxorrhina  and  Elephantomyia  the  proboscis  is  as  long  as 
the  whole  body.  In  other  forms  the  wings  become  elongated  lo 
an  unusual  extent  by  means  of  a  basal  stalk.  It  is  probable 
that  the  elongation  of  the  rostrum  may  be  useful  to  the  Insects. 
Gosse,1  indeed,  describes  Limndbia  intermedia  as  having  a  rostrum 
half  as  long  as  the  body,  and  as  hovering  like  a  Syrphid,  but 
this  is  a  habit  so  foreign  to  Tipulidae,  that  we  may  be  pardoned 
for  suspecting  a  mistake.  The  larvae  exhibit  a  great  variety  of 
form,  some  being  terrestrial  and  others  aquatic,  but  the  ter- 
restrial forms  seem  all  to  delight  in  damp  situations,  such 
as  shaded  turf  or  rotten  tree-stems.  They  are  either  amphi- 
pneustic  or  metapneustic,  that  is,  with  a  pair  of  spiracles  placed 
at  the  posterior  extremity  of  the  body ;  the  aquatic  species 
frequently  bear  appendages  or  projections  near  these  spiracles. 
The  pupae  in  general  structure  are  very  like  those  of  Lepidoptera, 
and  have  the  legs  extended  straight  along  the  body  ;  they  possess 
a  pair  of  respiratory  processes  on  the  thorax  in  the  form  of 
horns  or  tubes. 

There  are  more  than  1000  species  of  these  flies  known, 
and  many  genera.  They  form  three  sub-families,  which  are  by 
some  considered  distinct  families,  viz. :  Ptychopterinae,  Limno- 
biinae  or  Tipulidae  Brevipalpi,  Tipulinae  or  Tipulidae  Longi- 
palpi. 

The  Ptychopterinae  are  a  small  group  in  which  the  angulate 

1  A  2?iitn,ni  list's  XtijiiHi-ii,  in  Jamaica,  London,  1853,  p.  284. 


VII 


TIPULIDAE 


473 


r— 


suture  of  the  mesonotmu  is  indistinct ;  the  larvae  are  aquatic  and 
have  the  head  free,  the  terminal  two  segments 
of  the  body  enormously  prolonged  (Fig.  223), 
forming  a  long  tail  hearing,  in  the  North 
American  Bittacomorpha,  two  respiratory  h' la- 
ments. Hart *  describes  this  tail  as  possessing 
a  stigmatal  opening  at  the  extremity  ;  no  doubt 
the  structure  is  a  compounded  pair  of  spiracles. 
The  pupa  (Fig.  223,  B)  has  quite  lost  the  respira- 
tory tube  at  the  posterior  extremity  of  the 
body,  but  has  instead  quite  as  long  a  one  at 
the  anterior  extremity,  due  to  one  tube  of  the 
pair  normal  in  Tipulidae  being  enormously 
developed,  while  its  fellow  remains  small.  This 
is  a  most  curious  departure  from  the  bilateral 
symmetry  that  is  so  constantly  exhibited  in 
Insect-structure.  Our  British  species  of  Ptycli- 
optera  have  the  pupal  respiratory  tube  as  extra- 
ordinary as  it  is  in  BUtacomorpha,  though  the 
larval  tail  is  less  peculiar.2  This  group  should 
perhaps  be  distinguished  from  the  Tipulidae 
as  a  separate  family,  but  taxonornists  are  not 
yet  unanimous  as  to  this.  Brauer  considers 
that  the  head  of  the  larva,  and  the  condition 
of  five  Malpighian  tubules  in  the  imago, 
require  the  association  of  Ftychopterinae  with 
the  preceding  families  (Chironomidae,  etc.), 
rather  than  with  the  Tipulidae. 

The  great  majority  of  the  Tipulidae  are  com- 
prised in  the  suit-family  Limnobiinae — the 
Tipulidae  Brevipalpi  of  Osten  Sacken : 3  in 
them  the  last  joint  of  the  palpi  is  shorter  or  FIG.  223.  —  Bittaco- 
not  much  longer  than  the  two  preceding- 
together.  They  exhibit  great  variety,  and  many 
of  them  are  types  of  fragility.  The  common 
winter  gnats  of  the  genus  TricJ/ocera  are  a 
fair  sample  of  this  sub-family.  The  species 
of  this  genus  mostly  inhabit  high  latitudes,  and  delight  in 


morpha  davipes. 
North  America  x  j. 
(After  Hart.)  A, 
Larva  ;  B,  pupa : 

/,  the  left,  /•,  the 
right  respiratory 
tube. 


1  Bull.  Illiiwis  Lab.,  iv.  1895,  p.  193.  "  ^Hall's  Aquatic  Insects,  1895,  p.  174. 

3  "Studies,"  etc.,  L'crlin.  cut.  Zcitschr.  xxxi.  1887. 


474  DIPTERA  CHAV. 

a  low  temperature ;  it  has  l>een  said  that  they  may  be  seen 
011  the  wing  in  the  depth  of  winter  when  the  temperature  is 
below  freezing,  but  it  is  pretty  certain  that  the  spots  chosen  by- 
the  Insects  are  above  that  temperature,  and  Eaton  states  that  the 
usual  temperature  during  their  evolutions  is  about  40°  or  45° 
Fahr.  They  often  appear  in  the  damp  conditions  of  a  thaw 
when  much  snow  is  on  the  ground.  T.  simonyi  was  found  at  an 
elevation  of  9000  feet  in  the  Tyrol,  crawling  at  a  temperature 
below  the  freezing-point,  when  the  ground  was  deeply  covered  with 
snow.  T.  regelationis  occurs  commonly  in  mines  even  when  they 
are  500  feet  or  more  deep.  The  most  extraordinary  of  the 
Limnobiinae  is  the  genus  Chionea,  the  species  of  which  are  totally 
destitute  of  wings  and  require  a  low  temperature.  C.  araneoides 
inhabits  parts  of  northern  Europe,  but  descends  as  far  south  as 
the  mountains  near  Vienna  ;  it  is  usually  said  to  be  only  really 
active  in  the  depth  of  winter  and  on  the  surface  of  the  snow. 
More  recently,  however,  a  large  number  of  specimens  were  found 
by  Professor  Thomas  in  the  month  of  October  in  his  garden  in 
Thuringia ;  they  were  caught  in  little  pit-falls  constructed  to 
entrap  snails.  The  larva  of  this  Insect  is  one  of  the  interesting 
forms  that  display  the  transition  from  a  condition  with  spiracles 
at  the  sides  of  the  body  to  one  where  there  is  only  a  pair  at  the 
posterior  extremity. 

A  very  peculiar  Fly,  in  which  the  wings  are  reduced  to  mere 
slips,  Halirytus  amphibius,  was  discovered  by  Eaton  in  Kerguelen 
Land,  where  it  is  habitually  covered  by  the  rising  tide.  Though 
placed  in  Tipulidae,  it  is  probably  a  Chironomid. 

The  group  Cylindrotomina  is  considered  by  Osten  Sacken  a  to 
be  to  some  extent  a  primitive  one  having  relationship  with  the 
Tipulinae  ;  it  was,  he  says,  represented  by  numerous  species  in 
North  America  during  the  Oligocene  period.  It  is  of  great 
interest  on  account  of  the  larvae,  which  are  in  several  respects 
similar  to  caterpillars  of  Lepidoptera.  The  larva  of  Cylindrotoina 
<lix/i in-ia  lives  upon  the  leaves  of  plants — Anemone,  Viola, 
tflflliiriit — almost  like  a  caterpillar;  it  is  green  with  a  crest 
;ilnng  the  back  consisting  of  a  row  of  fleshy  processes.  Though 
this  fly  is  found  in  Britain  the  larva  lias  apparently  not  been 
observed  here.  The  life-history  of  Phalacrocera  rq>lici((a  has 
been  recently  published  by  Miall  and  Shelford.2  The  larva  eats 

1    7V.  ent.  Soc.  London.,  1897,  p.  362.        -   Tr.  cut.  Sue.  London,  1897,  pp.  343-361. 


VII 


TIPULIDAE BIBIOXIDAE 


475 


submerged  mosses  in  the  South  of  England,  and  bears  long  forked 
filaments,  reminding  one  of  those  of  caterpillars.  This  species 
has  been  simultaneously  discussed  by  Bengtsson,  who  apparently 
regards  these  Tipulids  with  caterpillar-like  larvae — he  calls  them 
Erucaeformia1 — as  the  most  primitive  form  of  existing  Diptera. 

The  Tipulinae — Tipulidae  Longipalpi,  Osten  Sacken2-  -have 
the  terminal  joint  of  the  palpi  remarkably  long,  longer  than  the 
three  preceding  joints  together.  The  group  includes  the  largest 
forms,  and  the  true  daddy-long-legs,  a  Chinese  species  of  which, 
Tipula  broldignagia,  measures  four  inches  across  the  expanded 
wings.  The  group  contains  some  of  the  finest  Diptera.  Some 
of  the  exotic  forms  allied  to  Ctenoplwra,  have  the  wings  coloured 
in  the  same  manner  as  they  are  in  certain  Hymenoptera,  and 
bear  a  considerable  resemblance  to  members  of  that  Order. 

Fam.  10.  Bibionidae. — Flies  of  moderate  or  small  size,  some- 
limes  of  different  colours  in  the  two  sexes,  with  short,  thick,  straight, 
antennae;  front  tibiae  usually  with  a  long  pointed  process; 
coxae  not  elongate.  Eyes  of  male  large,  united,  or  contiguous  in 


FIG.  224. — Head  of  Bibio.      x  10.     A,  Of  male,  seen  from  the  front  ;  C,  from  the  side  ; 
a,  upper,  b,  lower  eye  ;  B,  head  of  female. 

front.  The  flies  of  the  genus  Bibio  usually  appear  in  England 
in  the  spring,  and  are  frequently  very  abundant ;  they  are  of 
sluggish  habits  and  poor  performers  on  the  wing.  The  differ- 
ence in  colour  of  the  sexes  is  very  remarkable,  red  or  yellow 
predominating  in  the  female,  intense  black  in  the  male;  and 

1  A  eta  Univ.  Lund,  xxxiii.  (2)  Xo.  7,  1897. 
2  "Studies,"  etc.,  Berlin,  ent.  Zeitschr.  xxx.  1886,  p.  153. 


476 


DIPT  ERA 


CHAP. 


r      -V    «*  \ 

rli  K  N 


it  is  a  curious  fact  that  the  same  sexual  distinction  of  colour 
reappears  in  various  parts  of  the  world — England,  America,  India, 
and  New  Zealand ;  moreover,  this  occurs  in  genera  that  are  by 
no  means  closely  allied,  although  allied  species  frequently  have 
concolorous  sexes.  The  eyes  of  the  males  are  well  worth  study, 

there  being  a  very  large  upper  portion,  and, 
abruptly  separated  from  this,  a  smaller,  differ- 
ently faceted  lower  portion,  practically  a 
separate  eye  ;  though  so  largely  developed  the 
upper  eye  is  in  some  cases  so  hairy  that  it 
must  greatly  interfere  with  the  formation 
of  a  continuous  picture.  Carriere  con- 
siders that  the  small  lower  eye  of  the  male 
corresponds  to  the  whole  eye  of  the  female. 
The  larvae  of  Bilno  (Fig.  225)  are  caterpillar- 
like  in  form,  have  a  horny  head,  well  de- 
veloped, biting  mouth-organs,  and  spine-like 
processes  on  the  body-segments.  They  are 
certified  by  good  authorities1  to  possess  the  ex- 
tremely unusual  number  often  pairs  of  spiracles; 
a  larva  found  at  Cambridge,  which  we  refer  to 
Bibio  (Fig.  225)  has  nine  pairs  of  moderate 
spiracles,  as  well  as  a  large  terminal  pair 
separated  from  the  others  by  a  segment  without 
spiracles.  The  genus  Dilopli-us  is  closely 
allied  to  Bilrio,  the  larvae  of  which  (and  those 
of  Bibionidae  in  general)  are  believed  to  feed 
on  vegetable  substances ;  the  parasitism  of 
Dilophus  mil  gar  is  on  the  larva  of  a  rnoth,  Epino- 
FIG.  225.  —  Larva  of  tia  (Ckaetoptrio)  hypericana,  as  recorded  by 
Cam-  Meade,2  must  therefore  be  an  exceptional  case. 
In  the  genus  Scatopse  there  is  a  very  im- 
portant point  to  be  cleared  up  as  to  the  larval  respiratory 
system  ;  it  is  said  by  Dufour  and  Perris  8  to  be  amphipneustic ; 
there  are,  however,  nine  projections  on  each  side  of  the  body  that 
were  considered  by  Bouche,  and  probably  with  good  reason,  to 


A    H 

\  \ 


X 


M, 


•ff  /Y 

•*  v 
f  4 


ft 


H   *t 


* 


k 


/?M 


.t^Ki/ 


bridge.       x  5. 


1  Osten  Sackcn,  Berlin,  cnt.  Zcitscltr.  xxxvii.  1892,  p.  450. 

-  Kiilininili/ijist,,  xiv.  1881,  p.  287.     This  obsm  atiun  has  never,  we  believe,  been 
confirmed. 

:;  Ann.  Soc.  cut.  France  (2)  v.  1847,  p.  46. 


VII 


BIBIONIDAE — SIMULIIDAE 


477 


be  spiracles.  The  food  of  Seatopsc  in  the  larval  state  is 
principally  vegetable.  The  larva  of  Scatopse  changes  to  a 
pupa  inside  the  larval  p 

skin ;  the  pupa  is  pro- 
vided on  the  thorax  with 
two  branched  respiratory 


processes  that  project 
outside  the  larval  skin.1 
Lucas  has  given  an  in- 
teresting account  of  the 
occurrence  of  the  larva 
oiBiliio  marci  in  enorm- 
ous numbers  at  Paris ; 
they  lived  together  in 
masses,  there  being  ap- 
parently some  sort  of  FlG-  226.—  Portion  of  integument  of  Bibio  sp.  Cam- 
bridge, u,  Intersegmental  processes  ;  s,  spiracle. 

connection   between  the 

individuals.2      In  the   following  year  the  fly  was  almost  equally 

abundant. 

Owing  to  the  great  numbers  in  which  the  species  of  Bibionidae 
sometimes  appear,  these  Insects  have  been  supposed  to  be  very 
injurious.  Careful  inquiry  has,  however,  generally  exculpated 
them  as  doers  of  any  serious  injury,  though  Dilophus  febrilis — a 
so-called  fever-fly — appears  to  be  really  injurious  in  this  country 
when  it  multiplies  excessively,  by  eating  the  roots  of  the  hop- 
plant. 

Fam.  11.  Simuliidae  (Sand-flics,  Buffalo-gnats). — Small  obese 
flies  u'ith  It  limped  lack,  rather  short  legs  and  Inroad  v:in<js,  with  short, 
straight  n n/i'n n«e  destitute  of  setae;  proboscis  not  projecting. 
There  is  only  one  genus,  Simulium,  of  this  family,  but  it  is  very 
widely  spread,  and  will  probably  prove  to  be  nearly  cosmo- 
politan. Some  of  the  species  are  notorious  from  their  blood-suck- 
ing habits,  and  in  certain  seasons  multiply  to  an  enormous  extent, 
alight  in  thousands  on  cattle,  and  induce  a  disease  that  produces 
death  in  a  few  hours ;  it  is  thought  as  the  result  of  an  instilled 
poison.  S.  columbaczense  has  occasioned  great  losses  amongst 
the  herds  near  the  Danube;  in  North  America  the  Buffalo-  and 
Turkey-gnats  attack  a  variety  of  mammals  and  birds.  In  Britain 

1  IVrris,  in  Ann.  Soc.  ent.  France  (2)  v.  1847,  p.  37,  pi.  i. 
2  Ann.  Sue.  ent.  France  (5)  i.  1871,  Bull.  p.  Ixvii. 


DIPTERA  CHAP. 


and  other  parts  of  the  world  they  do  not  increase  in  numbers  to 
an  extent  sufficient  to  render  them  seriously  injurious  :  their  bite 
is  however  very  annoying  and  irritating  to  ourselves.  In  their 
early  stages  they  are  aquatic  and  require  well  aerated  waters : 
the  larvae  hold  themselves  erect,  fixed  to  a  stone  or  some  other 
object  by  the  posterior  extremity,  and  have  on  the  head  some 
beautiful  fringes  which  are  agitated  in  order  to  bring  food  within 
reach ;  the  pupae  are  still  more  remarkable,  each  one  being 
placed  in  a  pouch  or  sort  of  watch-pocket,  from  which  projects 
the  upper  part  of  the  body  provided  with  a  pair  of  filamentous 
respiratory  processes.  For  an  account  of  the  interesting  circum- 
stances connected  with  the  metamorphoses  of  this  species  the 
reader  should  refer  to  Professor  Miall's  book  ;  and  for  the  life- 
history  of  the  American  Buffalo-gnat  to  Eiley.1 

Fam.  12.  Rhyphidae.  —  -This  is  another  of  the  families  that 
have  only  two  or  three  genera,  and  yet  are  very  widely  distributed. 
These  little  flies  are  distinguished  from  other  Nemocera  Anomala 
(cf.  p.  456)  by  the  presence  of  a  disced  cell ;  the  em-podia  of  the 
feet  are  developed  as  if  they  were  pulvilli,  while  the  true  pulvilli 
remain  rudimentary.  The  larvae  are  like  little  worms,  being 
long  and  cylindric;  they  are  amphipneustic,  and  have  been 
found  in  decaying  wood,  in  cow-dung,  in  rotten  fruits,  and 
even  in  dirty  water.  The  "petite  tipule,"  the  metamorphoses  of 
which  were  described  and  figured  by  Reaumur,  is  believed  to 
be  the  common  Rhyph.us  fenestralis?  R.  fenestralis  is  often 
found  on  windows,  as  its  name  implies. 


Series  2.  Orthorrhapha  Brachycera 

Fam.  13.  Stratiomyidae. — Antennae  with  three  segments 
a  terminal  complex  of  obscure  joints,  frequently  l>e«i'ing 
an  arista:  tibiae  not  spincd ;  wings  rather  small,  the  an- 
terior nervures  usually  much  more  st  rone/1  y  marked  than  those 
The  median  cell  small,  placed  near  to  the  middle  of  the 
Scutellum  fi'ii/iiiii/li/  x/i/'/icd;  terminal  appendages  of  the 

tarsi    small,    hut   pidvilli    and    a   pulvilli'form     empodium     are 

• 

1    Rep.  Dep.  A.jric.  Ent.   Jl'ashitKj/on,  1886,  p.  492. 

-  <T.  Reaumur,  Mem.   v.   17-10,  p.   21  ;  and  Perris,  Ann.  S'oc.  cnt.  France  (4)  x. 
l:  7D.  p.  190. 


vri  STRATIOMYIDAE-  -LEPTIDAE  479 

present.  This  is  a  large  family,  whose  members  are  very 
diversified,  consequently  definition  of  the  whole  is  difficult.  The 
species  of  the  typical  sub-family  Stratiomyinae  generally  have  the 
margins  of  the  body  prettily  marked  with  green  or  yellow,  and 
the  scutellum  spined.  In  the  remarkable  American  genus, 
Hermetia,  the  abdomen  is  much  constricted  at  the  base,  and  the 
scutellum  is  not  spined ;  in  the  division  Sarginae  the  body  is 
frequently  of  brilliant  metallic  colours.  The  species  all  have 
an  only  imperfect  proboscis,  and  are  not  blood-suckers.  The 
larvae  are  also  of  diverse  habits ;  many  of  those  of  the  Stratio- 
myinae are  aquatic,  and  are  noted  for  their  capacity  of  living  in 
salt,  alkaline,  or  even  very  hot  water.  Mr.  J.  C.  Hainon  found 
some  of  these  larvae  in  a  hot  spring  in  Wyoming,  where  he  could 
not  keep  his  hand  immersed,  and  he  estimated  the  temperature 
at  only  20°  or  30°  Fahr.  below  the  boiling-point.  The  larva 
of  Stratiomys  is  of  remarkably  elongate,  strap-like,  form,  much 
narrowed  behind,  with  very  small  head ;  the  terminal  segment 
is  very  long  and  ends  in  a  rosette  of  hairs  which  the  creature 
allows  to  float  at  the  surface.  After  the  larval  skin  is  shed  the 
pupa,  though  free,  is  contained  therein ;  the  skin  alters  but 
little  in  form,  and  has  no  organic  connection  with  the  pupa, 
which  merely  uses  the  skin  as  a  shield  or  float.  These  larvae 
have  been  very  frequently  described ;  they  can  live  out  of  the 
water.  Brauer  describes  the  larvae  of  the  family  as  "  perip- 
neustic,  some  perhaps  amphipneustic."  Miall  says  there  are,  in 
Stratiomys,  nine  pairs  of  spiracles  011  the  sides  of  the  body  which 
are  not  open,  though  branches  from  the  longitudinal  air-tubes 
pass  to  them.  There  are  probably  upwards  of  1000  species  of 
Stratiomyiidae  known,  and  in  Britain  we  have  40  or  50  kinds. 
The  American  genus  Chiromyza,  Wied.,  was  formerly  treated  by 
Osten  Sacken  as  a  separate  family,  Chiromyzidae,  but  Williston 
places  it  in  Stratiomyidae. 

Fam.  14.  Leptidae,  including  Xylophagidae  and  Coenomyi- 
idae. — The  Leptidae  proper  are  flics  of  feeble  luild ;  anti'n  ii<n> 
with  three  joints  and  a  terminal  bristle ;  in  the  Xylophagidae  the 
antennae  are  longer,  and  the  third  joint  is  complex.  The  id IKJ* 
have  Jive  posterior  cells,  the  middle  tibiae  are  spined.  PulviUl  ami  // 
pulmlliform  empodium  present.  The  three  families  are  considered 
distinct  by  most  authors,  but  there  has  always  been  much  difficulty 
about  the  Xylophagidae  and  Coenomyiidae,  we  therefore  treat  them 


480 


DIPTERA 


CHAP. 


as  sub-families.  The  Xylophaginae  are  a  small  group  of  slender 
Insects,  perhaps  most  like  the  short-bodied  kinds  of  Asilidae ; 
the  third  joint  of  the  antenna  is  vaguely  segmented,  and  there 
is  no  terminal  bristle.  Rhachicerus  is  a  most  anomalous 
little  fly  with  rather  long  stiff  antennae  of  an  almost  nemo- 
cerous  character,  the  segments  of  which  give  off  a  short 
thick  prolongation  on  each  side,  reminding  one  of  a  two-edged 
saw.  The  three  or  four  British  species  of  Xylophaginae 
are  forest  Insects,  the  larvae  of  which  live  under  bark,  and 
are  provided  with  a  spear-like  head  with  which  they  pierce 
other  Insects.  The  Coenomyiinae  consist  of  the  one  genus 
Coenomyia,  with  two  or  three  European  and  Xorth  American 
species.  They  are  remarkably  thick-bodied,  heavy  flies,  reminding 
one  somewhat  of  an  imperfect  Stratiomyid  destitute  of  orna- 
mentation. The  metamorphosis  of  C.  ferruginea  has  been 
described  by  Bering.1  The  larva  is  not  aquatic,  but  lives  in 
burrows  or  excavations  in  the  earth  where  there  are,  or  have 
recently  been,  rotten  logs ;  it  is  probably  predaceous.  It  is 
cylindric,  with  an  extremely  small  head  and  eleven  other  segments, 
the  stigma  on  the  first  thoracic  segment  distinct ;  the  terminal 
segment  is  rather  broad,  and  the  structures  surrounding  the 
stigma  are  complex.  The  pupa 
has  stigmata  on  each  of  ab- 
dominal segments  2  to  8.  Not- 
withstanding that  the  fly  is  so 
different  to  Xylophagus,  the 
larvae  indicate  the  two  forms 
as  perhaps  really  allied.  One 
of  the  Leptinae,  Atltcrix  ilns, 
has  a  singular  mode  of  ovi- 
position  (Fig.  227),  the  females 
of  the  species  deposit  their  eggs 
in  common,  and,  dying  as  they 
do  so,  add  their  bodies  to  the 
common  mass,  which  becomes  YiG.2-27.—Atli?ri.vil>is.  A,  The  fly,  nnt. 
an  agglomeration,  it  may  be  size  ;  B,  mass  of  dead  flies  overhanging 

water,  much  reduced. 

of  thousands  of  individuals,  and 

of  considerable   size.      The    mass    is    attached   to   a   branch   of  a 

bush    or    to    a    plant    overhanging    water,    into    which     it     ulti- 

1    rcrh.  Gcs.   Wicn,  xxx.  1880,  p.  343. 


VII 


LEPTIDAE TABANIDAE 


481 


mately  falls.  These  curious  accumulations  are  occasionally 
found  in  England  as  well  as  on  the  Continent,  but  no  reason 
for  so  peculiar  a  habit  is  at  present  forthcoming.  Still  more 
remarkable  are  the  habits  of  some  European  Leptids  of  the 
genera  Vermileo  (Psammorycter  of  some  authors)  and  Lamp- 
r<>  in  i/ i«.,  slender  rather  small  flies  of  Asilid-like  appearance,  the 
larvae  of  which  form  pit-falls  after  the  manner  of  the  Ant-lion. 
According  to  Beling  l  the  larva  of  Leptis  is  very  active,  and  is 
distinguished  by  having  the  stigmatic  orifice  surrounded  by  four 
quite  equal,  quadrangularly  placed  prominences ;  and  at  the  other 


FIG.  228.— Larva  of 
Vermileo  degeeri 
(Psammorycter  ver- 
inili'ii}.  A,  lateral, 
B,  dorsal  view: 
}),  an  abdominal 
pseudopod  ;  st, 
stigma.  Europe. 
(After  Reaumur 
and  Brauer.) 


extremity  of  the  body  a  blackish,  naked,  triangular  plate ;  on  the 
under  side  of  each  of  seven  of  the  abdominal  segments  there  is  a 
band  of  spines.  The  larva  ofAtkerix  has  seven  pairs  of  abdominal 
feet.  Altogether  there  are  .some  two  or  three  hundred  known 
species  of  Leptidae  ;  our  British  species  scarcely  reach  a  score. 
They  are  destitute  of  biting-powers  and  are  harmless  timid 
creatures.  Leptis  scolopacea,  the  most  conspicuous  of  our  native 
species,  a  soft-bodied  fly  of  rather  large  size,  the  wings  much 
marked  with  dark  colour,  and  the  thick,  pointed  body  yellowish, 
marked  with  a  row  of  large  black  spots  down  the  middle,  is  a 
common  Insect  in  meadows. 

Fam.  15.  Tabanidae  (Breeze  -  flies,  Cle.ggs,  or  Horse-flies, 
also  frequently  called  Gad-flies). — Proboscis  fleshy,  distinct,  en- 
wrapping  pointed,  horny  processes,  palpi  distinct,  terminal  joint 
inflated,  pendent  in  front  of  proboscis.  Antennae  projecting,  four- 
jointed,  second  joint  very  short,  third  variable  in  form,  fourth 
forming  an  indistinctly  segmented  continuation  of  the  third,  but 
not  ending  in  a  bristle.  A  perfect  squama  in  front  of  the  halter. 
Eyes  large,  very  large  in  the  males,  but  laterally  extend-in  tf,  r«ther 
than  globose.  This  large  and  important  family  of  flies,  of  which 

1  Arch.  Naturgcs.  xli.  i.  1875,  p.  48. 
VOI.  VI  2  I 


482 


DIPTERA 


CHAP. 


AVilliston  states  that  1400  or  1500  species  are  named,  is 
well  known  to  travellers  on  account  of  the  blood  -  sucking 
hahits  of  its  members  ;  they  have  great  powers' 
of  flight,  and  alight  on  man  and  animals,  and 
draw  blood  by  making  an  incision  with  the 
proboscis ;  only  the  females  do  this,  the 
males  wanting  a  pair  of  the  lancets  that 
enable  the  other  sex  to  inflict  their  for- 
midable wounds.  They  are  comparatively  large 
Insects,  some  of  our  English  species  of  Talmnus 
attaining  an  inch  in  length.  The  smaller,  grey 
ffaematopota,  is  known  to  every  one  who  has 
walked  in  woods  or  meadows  in  the  summer,  as 
it  alights  quietly  on  the  hands  or  neck  and 
bites  one  without  his  having  previously  been 
made  aware  of  its  presence.  The  larger  Tabani 
hum  so  much  that  one  always  knows  when  an 
individual  is  near.  The  species  of  Chrysops,  in 
habits  similar  to  Haeiiiatopota ,  are  remarkable 
for  their  beautifully  coloured  golden-green  eyes. 
In  Brazil  the  Motuca  fly,  Hadrus  lepidotus, 
Perty,  makes  so  large  and  deep  a  cut  that  con- 
siderable bleeding  may  follow,  and  as  it  some- 
times settles  in  numbers  on  the  body,  it  is 
deservedly  feared.  The  most  remarkable  forms 

FIG.  229.—  I',lli;,o,w-t  .J 

lonffirostris.  of  Tabanidae  are  the  species  of  the  widely  dis- 

1    Nepal.   (After  tributed  genus  Pam/onia  (Fig.  229).      The  pro- 

Hardwicke. ) 

boscis  in  the  females  of  some  ot  the  species  is 
three  or  four  times  the  length  of  the  body,  and  as  it  is  stiff  and 
needle-like  the  creature  can  use  it  while  hovering  on  the  wing,  and 
will  pierce  the  human  body  even  through  clothing  of  considerable 
thickness.  The  males  suck  the  juices  of  flowers.  The  Seroot 
fly,  that  renders  some  of  the  districts  of  Xubia  uninhabitable 
for  about  three  months  of  the  year,  appears,  from  the  figure  and 
description  given  by  Sir  Samuel  Baker,  to  be  a  Pangonia. 
Tabani* lae  are  a  favourite  food  of  the  fossorial  wasps  of  the 
family  Bembecidiic.  These  wasps  are  apparently  aware  of  the 
bloo(l-su<.-king  habits  of  their  favourites,  and  attend  on  travellers 
and  pick  up  the  flies  as  they  are  about  to  settle  down  to  their 
phlebotomic  operations.  The  larvae  of  the  Tabanidae  are  s 


VII 


TABANIDAE-  -ACANTHOMERIDAE 


483 


of  them  aquatic,  but  others  live  in  the  earth  or  in  decaying 
wood ;  they  are  of  predaceous  habits,  attacking  and  suckiiif 
Insect -larvae,  or  worms.  Their  -form  is  cylindric,  attenuate 
at  the  two  extremities;  the  slender  small  head  is  retractile,  and 
armed  with  a  pair  of  conspicuous,  curved  black  hooks.  The 
body  is  surrounded  by  several  promi- 
nent rings.  The  breathing  apparatus  is 
apparently  but  little  developed,  and  con- 
sists of  a  small  tube  at  the  extremity  of 
the  body,  capable  of  being  exserted  or 
withdrawn  ;  in  this  two  closely  approxi- 
mated stigmata  are  placed.  In  a  larva, 
probably  of  this  family,  found  by  the 
writer  in  the  shingle  of  a  shallow  stream 
in  the  New  Forest,  the  annuli  are  re- 
placed by  seven  circles  of  prominent 
pseudopods,  on  the  abdominal  segments 
about  eight  in  each  circle,  and  each  of 
these  feet  is  surmounted  by  a  crown  of 
small  hooks,  so  that  there  are  fifty  or 
sixty  feet  distributed  equally  over  the 
middle  part  of  the  body  without  refer- 
ence to  upper  or  lower  surface.  The 

FIG.  230.  — Larva  of  a  Taba- 

tigures    of    the    larva    ot    1.    cordiycr,  by        nid.     \]  Atylotus  fui-ms.} 
l.rauer,  and  of  Hacmatopota  pluvialis,  by        f"  the   hm-a      :  3;    B, 

J  head  ;    C,    end    of  body  ; 

Perris,  are  something  like  this,  but   have        D,  one  of  the  pseudopods. 
no  setae  on   the   pseudopods.      The  meta- 
morphoses of  several  Tabanidae  are  described  and  figured  by  Hart ; x 
the  pupa  is  remarkably  like  a  Lepidopterous  pupa.     We  have  five 
genera  and  about  a  score  of  species  of  Tabanidae  in  Britain. 

Fam.  16.  Acanthomeridae. — A  very  small  family  of  two 
genera  (Acan f/n>i/i <•/•«  and  Ehaphiorhynclius]  confined  to  America, 
and  including  the  largest  Diptera,  some  being  two  inches  long. 
The  antenna  is  terminated  by  a  compound  of  seven  segments  and 
a  style ;  the  proboscis  is  short,  and  the  squama  rudimentary. 
The  general  form  reminds  one  of  Tabanidae  or  Oestridae.  A 
dried  larva  exists  in  the  Vienna  collection  ;  it  is  amphip'neustic, 
and  verv  remarkable  on  account  of  the  great  size  of  the  anterior 

v  O 

'  stigma. 

1  Bull.  Illinois  Lai.  iv.  1895. 


DIPTERA 


CHAP. 


Fam.   17.   Therevidae. 

the   appearance   of  short 


Moderate-sized  flies,  with   somewhat 
Asilidae.       Tliei/   linre,    hoirerer,   only   a 


feeble    //<•*•////  proboscis,  and   minute    claws,  with   pulinlli    hut    no' 

e  in /indium  ;  the  antennae  project,  are  short, 
three -jointed,  pointed. — The  flies  of  this 
family  care  believed  to  he  predaceous  like 
the  Eobber-flies,  but  they  appear  to  be  very 
feebly  organised  for  such  a  life.  We  have 
about  ten  species  in  Britain,  and  there 
are  only  some  200  known  from  all  the 
world.  But  little  is  known  as  to  the  meta- 
morphoses. Meigeii  found  larvae  of  T. 
nohilitdta  in  rotten  stumps,  but  other  larvae 

FIG.  231,—Therera  (Psilo- 

cephala)  confinis.    A,    have  been  recorded  as  devouring  dead  pupae 
Pupa ;  B, larva  Euro!*.  or  iarvae  of  Lepidoptera.     The  larvae  are  said 

(Alter  Perns.) 

to  be  elongate,  very  slender,  worm-like,  and 

to  have  nineteen  body-segments,  the  posterior  pair  of  spiracles 
being  placed  on  what  looks  like  the  seventeenth  segment,  but  is 
really  the  eighth  uf  the  abdomen.  The  pupa  is  not  enclosed 
in  the  larval  skin;  that  of  Psilocephala  is  armed  with  setae  and 
spinous  processes,  and  was  found  in  rotten  wood  by  Frauenfeld. 

Fam.  18.  Scenopinidae. — luitlier  x>n<dl  ///<•*,  witlnmt  bristle*. 
Antennae  three-jointed,  the  third  joint  rather  Ion;/,  without  «j>- 
pendage.  ProJioscis  not  jirojecting.  Empodium  ahsent.  These 
unattractive  Mies  form  one  of  the  smallest  families,  and  are 
chiefly  found  on  windows.  >S'.  fenextndis  looks  like  a  tiny 
Si  ratiomyid,  with  a  peculiar,  dull,  metallic  surface.  The  larva 
of  this  species  has  been  recorded  as  feeding  on  a  variety  of 
strange  substances,  but  Osten  Sacken  is  of  opinion !  that  it  is 
really  predaceous,  and  frequents  these  substances  in  order  to  find 
the  larvae  that  are  developing  in  them.  If  so,  Scenopinus  is  useful 
in  a  small  way  by  destroying  "  moth,"  etc.  The  larva  is  a  little 
slender,  cylindrical,  hard,  pale  worm  of  nineteen  segments,  with  a 
small  brown  head  placed  like  a  hook  at  one  extremity  of  the  body 
and  with  two  short,  divergent  processes  at  the  other  extremity, 
almost  exactly  like  the  larva  of  There m.  Full  references  to  the 
literature  about  this  Insect  are  <riven  bv  Osten  Sacken. 

O  i/ 

Fam.  19.  Nemestrinidae. — These  Insects  appear  to  be  allied 
to  the  Bombyliidae.      They  are  of  medium  size,  often  pilose,  and 

1  Eut.  Muy.  xxiii.  188(3,  p.  51. 


vii  NEMESTRINIDAE BOMBYLIIDAE  485 


sometimes  with  excessively  long  proboscis;  antennae  short,  with  a 
xiinnle  third  joint,  and  a  jointed,  slender,  terminal  appendage  ;  the 
filmic  hare  'tin  spurs,  the  empodium  is  pulvillus-like.  The  iving- 
mrni  ration  /.s  perhaps  tlie  most  complex  found  in  Diptcra,  there 
In' ing  numerous  cells  at  the  tip,  almost  after  the  fashion  of 
Neuroptera.  With  this  family  we  commence  the  aerial  forms 
composing  the  Tromoptera  of  Osten  Sacken.  JSTemestrinidae  is  a 
small  family  of  about  100  species,  hut  widely  distributed. 
Megistorhynchus  longirostris  is  about  two-thirds  of  an  inch  long, 
but  has  a  proboscis  at  least  four  times  as  long  as  itself.  In 
South  Africa  it  may  be  seen  endeavouring  to  extract,  with  this 
proboscis,  the  honey  from  the  flower  of  a  Gladiolus  that  has  a 
perianth  just  as  long  as  its  own  rostrum  ;  as  it  attempts  to  do  this 
when  it  is  hovering  on  the  wing,  and  as  the  proboscis  is,  unlike 
that  of  the  Bornbylii,  fixed,  the  Insect  can  only  succeed  by  con- 
trolling its  movements  with  perfect  accuracy ;  hence  it  has  great 
difficulty  in  attaining  its  purpose,  especially  when  there  is  much 
wind,  when  it  frequently  strikes  the  earth  instead  of  the  flower. 
M.  "Westermann  thinks  x  the  life  of  the  Insect  and  the  appearance 
and  duration  of  the  flower  of  the  Gladiolus  are  very  closely  con- 
nected. The  life-history  of  Hirmoneura  obscura  has  recently  been 
studied  in  Austria  by  Handlirsch  and  Brauer.2  The  larva  is  par- 
asitic on  the  larva  of  a  Lamellicorn  beetle  (Rhizotrogus  solstitialis'} ; 
it  is  metapneustic,  and  the  head  is  highly  modified  for  predaceous 
purposes.  The  young  larva  apparently  differs  to  a  considerable 
extent  from  the  matured  form.  The  most  curious  fact  is  that  the 
parent  fly  does  not  oviposit  near  the  Lamellicorn-larva,  but  places 
her  eggs  in  the  burrows  of  some  wood-boring  Insect  in  logs ;  the 
larvae  when  hatched  come  to  the  surface  of  the  log,  hold  them- 
selves up  on  their  hinder  extremity  and  are  carried  away  by  the 
wind  ;  in  what  manner  they  come  into  contact  with  the  Lamellicorn 
larva,  which  feeds  in  turf,  is  unknown.  The  pupa  is  remarkable 
on  account  of  the  prominent,  almost  stalked  stigmata,  and  of  two 
pointed  divergent  processes  at  the  extremity  of  the  body.  This 
life-history  is  of  much  interest,  as  it  foreshadows  to  some  extent 
the  complex  parasitic  life-histories  of  Bornbyliidae.  The  Neines- 
trinidae  are  not  represented  in  the  British  fauna, 

Fam.  20.  Bombyliidae. — Body  frequently  fringed  with  dou-n, 

1  Ann.  Soc.  ent.  France,  ii.  1833,  p.  492. 
2   Wien.  ent.  Zcit.  ii.  1883,  pi>.  11  and  24,  pi.  i. 


486 


DIPTERA 


CHAT 


or  covered  in  large  part  with  hair.  Legs  slender,  claws  smtdl, 
without  distinct  empodium,  usually  with  only  minute  pulvilli. 
Proboscis  rn-y  long  or  moderate,  antennae  three-jointed,  terminal 
joint  not  distinctly  diridcd,  sometimes  large,  sometimes  hair-like. 
This  is  a  very  large  family,  including  1500  species,  and  is  of 
great  importance  to  both  naturalist  and  economist.  Two  well- 
marked  types,  formerly  treated  as  distinct  families,  are  included  in 
it — (1)  the  Bomby Hides  with  very  long  exserted  rostrum,  and 
humped  thorax;  and  (2)  Anthracides,  with  a  short  beak,  and  of 
more  slender  and  graceful  form.  None  of  these  flies  are  blood- 
suckers, they  frequent  flowers  only,  and  use  their  long  rostrums  in 
a  harmless  manner.  The  members  of  both  of  these  groups  usually 
have  the  wings  ornamented  with  a  pattern,  which  in  Anthrax 
is  frequently  very  remarkable ;  in  both,  the  clothing  of  the  body 
is  frequently  variegated.  Their  powers  of  flight  are  very  great, 
and  the  hovering  Bomlnjlius  of  early  spring  is  endowed  with  an 
unsurpassed  capacity  for  movement,  remaining  perfectly  still  on 
the  wing,  and  darting  off  with  lightning  rapidity ;  Anthrax  is 
also  most  rapid  on  the  wing.  In  Britain  we  have  but  few 
species  of  Bombyliidae,  but  in  warm  and  dry  climates  they  are 
very  numerous.  The  life-history  of  these  Insects  was  till  recently 

unknown,  but  that  of  Argyro- 
moelia  (^Anthrax)  trifaseiata  has 
been  described  by  the  French 
naturalist,  Fabre,  who  ascertained 
that  the  species  is  parasitic  on  the 
Mason-bee,  Chalicodoma  muraria, 
that  forms  nests  of  solid  mas- 
onry. He  endeavoured  to  dis- 
cover the  egg,  but  failed ;  the 
parent -fly  oviposits,  it  appears, 
by  merely  dropping  a  minute 
egg  while  flying  over  the  surface 
of  the  mass  of  masonry  by  which 

the  grubs  of  the  Chalicodoma  are 
Bio.  232. — Argyromoeoa  tn/asciata.     A, 

Young   larva;  B,  adult   larva;    c.   protected.      ±  roni  this  egg  there 

is  hatched  a  minute  delicate  ver- 
miform larva  (Fig.  232,  A).  In 
order  to  obtain  its  food,  it  is  necessary  for  this  feeble  creature  to 
penetrate  the  masonry;  apparently  a  hopeless  task,  the  animal 


jiupa.         France.         (After      Fabre.] 
A,  Greatly,  B,  C,  slightly  niagnitk-d. 


VII 


BOMBYLIIDAE  487 


being  scarcely  a  twentieth  of  an  inch  long  and  very  slender  ;  it 
is,  however,  provided  with  a  deflexed  horny  head,  armed  in  front 
with  some  stiff  bristles,  while  on  the  under  surface  of  the  body 
there  are  four  pairs  of  elongate  setae  serving  as  organs  of  loco- 
motion :  thus  endowed,  the  frail  creature  hunts  about  the  sur- 
face of  the  masonry,  seeking  to  find  an  entrance ;  frequently  it 
is  a  long  time  before  it  is  successful ;  but  though  it  lias  never 
taken  any  food  it  is  possessed  of  great  powers  of  endurance. 
Usually,  after  being  disclosed  from  the  egg,  it  remains  about 
fifteen  days  without  stirring  ;  and  even  after  it  commences  its 
attempts  to  enter  the  nest  it  is  still  capable  of  a  long  life  without 
taking  any  food.  Possibly  its  organisation  will  not  permit  it  to 
feed  (supposing  any  food  were  obtainable  by  it)  without  its 
growing  somewhat  thereafter,  and  if  so,  its  chance  of  obtaining 
entrance  through  the  masonry  would  be  diminished.  Abstention, 
it  would  appear,  is  the  best  policy,  whether  inevitable  or  not ; 
so  the  starving  little  larva  continues  its  endeavours  to  find  a 
chink  of  entrance  to  the  food  contained  in  the  interior  of  the 
masonry.  It  has  plenty  of  time  for  this,  because  it  is  better  for 
it  not  to  get  into  the  cell  of  the  bee  until  the  grub  is  quite  full 
grown,  and  is  about  to  assume  the  pupal  form,  when  it  is  quite 
incapable  of  self-defence.  Finally,  after  greater  or  less  delay, 
the  persevering  little  larva  succeeds  in  finding  some  tiny  gap  in 
the  masonry  through  which  it  can  force  itself.  M.  Fabre  says 
that  the  root  of  a  plant  is  not  more  persistent  in  descending 
into  the  soil  that  is  to  support  it  than  is  this  little  Anthrax 
in  insinuating  itself  through  some  crack  that  may  admit  it  to  its 
food.  Having  once  effected  an  entrance  the  organisation  that 
has  enabled  it  to  do  so  is  useless ;  this  primary  form  of  the  larva 
has,  in  fact,  as  its  sole  object  to  enable  the  creature  to  penetrate  to 
its  food.  Having  penetrated,  it  undergoes  a  complete  change  of 
form,  and  appears  as  a  creature  specially  fitted  for  feeding  on  the 
quiescent  larva  of  the  bee  without  destroying  it.  To  accomplish 
this  requires  an  extreme  delicacy  of  organisation  and  instinct ; 
to  bite  the  prey  would  be  to  kill  it,  and  if  this  were  done,  the 
Anthrax  would,  Fabre  supposes,  ensure  its  own  death,  for  it 
cannot  feed  on  the  dead  and  putrefying  grub  ;  accordingly,  the 
part  of  its  body  that  does  duty  as  a  mouth  is  merely  a  delicate 
sucker  which  it  applies  to  the  skin  of  the  Ckalicodoma-grnb ; 
and  thus  without  inflicting  any  perceptible  wound  it  sucks  day 


488  DIPTERA  CHAP. 

after  day,  changing  its  position  frequently,  until  it  has  completely 
emptied  the  pupa  of  its  contents,  nothing  being  left  but  the  skin. 
Although  this  is  accomplished  without  any  wound  being  inflicted,- 
so  effectual  is  the  process  that  all  the  Chalicodoma  is  gradually 
absorbed.  The  time  requisite  for  completely  emptying  the  victim 
is  from  twelve  to  fifteen  days ;  at  the  end  of  this  time  the 
Anthrax-larva,  is  full  grown,  and  the  question  arises,  how  is  it  to 
escape  from  the  cell  of  solid  masonry  in  which  it  is  imprisoned  ? 
It  entered  this  cell  as  a  tiny,  slender  worm  through  a  minute 
orifice  or  crack,  but  it  has  now  much  increased  i-n  size,  and  exit 
for  a  creature  of  its  organisation  is  not  possible.  For  some 
months  it  remains  a  quiescent  larva  in  the  cell  of  the  Chali- 
codoma, but  in  the  spring  of  the  succeeding  year  it  undergoes 
another  metamorphosis,  and  appears  as  a  pupa  provided  with  a 
formidable  apparatus  for  breaking  down  the  masonry  by  which 
it  is  imprisoned.  The  head  is  large  and  covered  in  front  with 
six  hard  spines,  to  be  used  in  striking  and  piercing  the  masonry, 
while  the  other  extremity  of  the  body  bears  some  curious  horns, 
the  middle  segments  being  armed  with  rigid  hairs  directed  back- 
wards, and  thus  facilitating  movement  in  a  forward  direction  and 
preventing  slipping  backwards.  The  pupa  is  strongly  curved, 
and  fixes  itself  by  the  aid  of  the  posterior  spines ;  then,  unbend- 
ing itself,  it  strikes  with  the  armour  of  the  other  extremity 
against  the  opposing  wall,  which  is  thus  destroyed  piecemeal 
until  a  gallery  of  exit  is  formed  ;  when  this  is  completed  the 
pupa -skin  bursts  and  the  perfect  fly  emerges,  leaving  the 
pupa-case  still  fixed  in  the  gallery.  Thus  this  species  appears 
in  four  consecutive  forms — in  addition  to  the  egg — each  of 
which  is  highly  specialised  for  the  purposes  of  existence  in  that 
stage. 

The  habits  of  our  British  Bombylius  major  have  been  partially 
observed  by  Dr.  Chapman,1  and  exhibit  a  close  analogy  with 
those  of  Anthrax  trifasciata.  The  bee-larva  that  served  as  food 
was  in  this  case  Andrena  labialis,  and  the  egg  was  deposited 
by  the  fly,  when  hovering,  by  jerking  it  against  the  bank  in 
which  the  nest  of  the  bee  was  placed. 

It  has  recently  been  discovered  that  the  larvae  of  various 
species  of  Bombyliidae  are  of  great  service  by  devouring  the 
eggs  of  locusts.  Riley  found  that  the  egg-cases  of  Caloptcnus 

1   Ent.  Maij.  xiv.  1878,  i>.  196. 


VII 


BOMBYLIIDAE ACROCERIDAE 


489 


spretus  are  emptied  of  their  contents  by  the  larvae  of  Systoechus 
areas  and  Triodites  mus.  A  similar  observation  has  been  made 
in  the  Troacl  by  Mr.  Calvert,  who  found  that  the  Bombyliid, 
Callostoma  fascipennis,  destroys  large  quantities  of  the  eggs  of 
Ccdoptenus  italicus.  Still  more  recently  M.  Kiinckel  d'Herculais 
has  discovered  that  the  destructive 
locust  Stauronotus  maroccanus  is 
kept  in  check  in  Algeria  in  a 
similar  manner,  as  many  as  80 
per  cent  of  the  eggs  of  the  locust 
being  thus  destroyed  in  certain 
localities.  He  observes  that  the 
larva  of  the  fly,  after  being  full 
fed  in  the  autumn,  passes  the 
winter  in  a  state  of  lethargy- 
he  calls  it  "  hypnody '  -in  the 

egg-case    of    the    locust,    and    he 

P      .,  .    P  .  FIG.    233. — Systropus    cnulelis.      South 

turther   informs   us    that    in    the        Afri™      A,  Piipa  ;   B,  imago,    ap- 


Africa. 

pendages   of   the    left    side   removed. 

(After  Westwood.) 


case  of  Anthrax  fenestralis,  which 
devours  the  eggs  of  the  large 
Ocnerodes,  the  lethargy  may  be  prolonged  for  a  period  of  three 
years.  After  the  pupa  is  formed  it  works  a  way  out  of  the  case 
by  means  of  its  armature,  and  then  again  becomes  for  some  days 
immobile  before  the  perfect  fly  appears.  Lepidopterous  larvae 
are  also  attacked  by  Bombyliid  flies.  A  species  of  Systropus  has 
been  recorded  as  destroying  the  larva  of  Limacodes.  Several  of 
the  Bombyliids  of  the  genus  just  mentioned  are  remarkable  for 
the  great  resemblance  they  display  to  various  Hymenoptera,  some 
of  them  being  very  slender  flies,  like  the  thin  bodied  fossorial 
Hymenoptera.  The  difference  between  the  pupa  and  imago  in 
this  case  is  very  remarkable  (Fig.  233). 

Fam.  21.  Acroceridae  or  Cyrtidae. — Flics  of  the  average  size, 
of  peculiar  form,  the  small  head  consisting  almost  entirely  of  tin 

*,  and  lent  down  under  the  humped  thorax  :  wings  small,  halteres 
hj  concealed  by  the  very  large  horizontal  squamae;  antennae 
very  diverse.  The  peculiar  shape  of  these  flies  is  an  exaggeration  of 
that  we  have  already  noticed  in  Bomliylms.  The  mouth  in  Acro- 
ceridae is  very  variable  ;  there  may  be  a  very  long,  slender  proboscis 
(Acrocera\  or  the  mouth-parts  may  be  so  atrophied  that  it  is 
doubtful  whether  even  an  orifice  exists  (Ogcodes\  There  are  but 


490 


DIPTERA 


CHAP. 


few  species  known,  and  all  of  them  are  rare ; 1  in  Britain  we 
have  but  two  (Of/codes  f/ililmxt'*,  Acrocera  glolulus}.  The  genus 
Pterodontia,  found  in  North  America  and  Australia,  an  inflated. 

bladder-like  form  with  a  minute  head,  is 
amongst  the  most  extraordinary  of  all  the 
forms  of  Diptera.  The  habits  are  very 
peculiar,  the  larvae,  so  far  as  known,  all 
living  as  parasites  within  the  bodies  of 
spiders  or  in  their  egg-bags.  It  appears, 
however,  that  the  flies  do  not  oviposit  in 
appropriate  places,  but  place  their  eggs  on 
FIG.  234. — Megalylnis  gm-  stems  of  plants,  and  the  young  larvae  have 

rf-r  ?A4;,(Aw°C?rida'r!  to  find  their  way  to  the  spiders.     Brauer  has 
Chili.  (Alter  Westwood.) 

described  the  larva  of   the   European   Asto- 

mella  lindeni?  which  lives  in  the  body  of  a  spider,  Cteniza 
ariana ;  it  is  amphipneustic  and  maggot-like,  the  head  being 
extremely  small.  The  larva  leaves  the  body  of  the  spider  for 
pupation  ;  the  pupa  is  much  arched,  and  the  head  is  destitute  of 
the  peculiar  armature  of  the  Bombyliidae,  but  has  a  serrate  ridge 
on  the  thorax.  Emerton  found  the  larvae  of  an  Acrocera  in  the 
webs  of  a  common  North  American  spider,  Amaurobius  sylvestris, 
they  having  eaten,  it  was  supposed,  the  makers  of  the  cobwebs. 

Fam.  22.  Lcnchopteridae. — Small,  slender  flies,  with  pointed 
wings,  short,  porrect  antennae,  ivith  a  simple,  circular  third  joint, 
bearing  a  bristle  ;  empodium  very  small, pulvilli  absent. — Only  one 
genus  of  these  little  flies  is  known,  but  it  is  apparently  widely 
distributed,  and  its  members  are  common  Insects.  They  have 
the  appearance  of  Acalyptrate  Muscidae,  and  the  nervuration  of 
the  wing  is  somewhat  similar,  the  nervures  being  simple  and 
parallel,  and  the  minute  cross -nervures  placed  near  the  base. 
The  systematic  position  is  somewhat  doubtful,  and  the  meta- 
morphoses are  but  incompletely  known,  very  little  having  been 
added  to  what  was  discovered  by  Sir  John  Lubbock  in  1862.3 
The  larva  lives  on  the  earth  under  vegetable  matter ;  it  is  very 
transparent,  amphipneustic,  with  a  peculiar  head,  and  with  fringes 
on  the  margins.  This  larva  changes  to  a  semi-pupa  or  apterous 
maggot-like  form,  within  the  larval  skin ;  the  true  pupa  .was 


& 


1  For  figures,  etc.,  cf.  Westwood,  Tr.  ent.  X<«'.  London,  1876,  p.  507,  pis.  v.  vi. 
'   J'cr/t.  Gat.  iricn,  xix.  1869,  p.  737,  pi.  xiii. 
3    Tr.  cut.  AW.  London  (3)  i.  1862,  p.  338,  pi.  \i. 


vii  LONCHOPTERIDAE MYDAIDAE ASILIDAE  491 

not  noticed  l>y  Lubbock,  but  Frauenfeld1  has  since  observed  it, 
though  he  only  mentions  that  it  possesses  differentiated  limbs 
and  segments.  The  metamorphoses  appear  to  be  very  peculiar. 
This  fly  requires  a  thorough  study. 

Fam.  23.  Mydaidae. — Large,  flies  of  elongate  form  ;  the  hind 
femora  long  and  toothed  beneath  ;  the  antennae  knobbed  at  the  tip, 
projecting,  rather  long,  the  basal  joint  definite,  but  the  divisions 
of  the  subsequent  joints  more  or  less  indistinct.  Empodium  small. 
Wings  frequently  heavily  pigmented ;  with  a  complex  nervuration. 
These  fine  flies  are  exotic ;  a  few  species  occur  in  the  Mediter- 
ranean region,  even  in  the  South  of  Europe  ;  the  chief  genus, 
My  das,  is  South  American,  but  most  of  the  other  genera  are 
Australian  or  African.  But  little  is  known  as  to  the  life- 
histories.  The  larvae  are  thought  to  live  in  wood,  and  to  prey 
on  Coleopterous  larvae. 

Fam.  24.  Asilidae  (Robber -flies}. — Mouth  forming  a  short, 
projecting  horny  beak,  the  palpi  usually  only  small;  the  feet 
generally  largely  developed;  the  claws  large, frequently  thick  ami 
blunt,  the  pulvilli  generally  elongate,  the  empodium  a  bristle  ; 
lialteres  free;  no  squama.  The  Asilidae  is  one  of  the  largest 
families  of  flies,  and  probably  includes  about  3000  described 
species :  as  will  readily  be  believed,  there  is  much  variety  of 
form  ;  some  are  short  and  thick  and  extremely  hairy,  superficially 
resembling  hairy  bees,  but  the  majority  are  more  or  less  elongate, 
the  abdomen  being  specially  long,  and  having  eight  segments 
conspicuously  displayed.  The  antennae  are  variable,  but  are 
three -jointed  with  a  terminal  appendage  of  diverse  form  and 
structure.  They  belong  to  the  super-family  Energopoda  of  Osten 
Sacken,  but  the  association  of  Empidae  and  Dolichopidae  with  them 
does  not  seem  to  be  very  natural.  In  their  perfect  state  these 
flies  are  most  voracious,  their  prey  being  Insects,  which  they 
seize  alive  and  impale  with  the  rostrum.  They  are  amongst 
the  most  formidable  of  foes  and  fear  nothing,  wasps  or  other 
stinging  Insects  being  attacked  and  mastered  by  the  stronger 
species  without  difficulty.  They  have  been  observed  to  capture 
even  dragon-flies  and  tiger-beetles.  As  is  the  case  with  so  many 
other  Insects  that  prey  011  living  Insects,  the  appetite  in  the 
Asilidae  seems  to  be  insatiable ;  a  single  individual  has  been 
observed  to  kill  eight  moths  in  twenty  minutes.  They  have 

1    Vcrli.  Ges.   JJ'fen,  xix.  1869,  p.  941. 


49 2  DIPTERA  CHAP. 

been  said  to  suck  blood  from  Vertebrates,  but  this  appears  to  be 
erroneous.  The  metamorphoses  of  a  few  species  have  been  ob- 
served. Ferris  has  called  attention  to  the  close  alliance  between' 
the  larvae  of  Tabanidae  and  of  Asilidae,1  and  it  seems  at  present 
impossible  to  draw  a  line  of  distinction  between  the  two.  So 
far  as  is  known,  the  larvae  of  Asilidae  are  terrestrial  and 
predaceous,  attacking  more  particularly  the  larvae  of  Coleoptera, 
into  which  they  sometimes  bore  ;  in  Lapliria  there  are  numerous 
pseudopods,  somewhat  of  the  kind  shown  in- Fig.  230,  but  less 
perfect  and  without  hairs ;  the  head  and  breathing  organs  appear 
to  be  very  different.  According  to  Beling's  descriptions  of  the 
larvae  of  Asilu.s,  the  head  in  this  case  is  more  like  that  of  the 
figure,  but  there  are  no  pseudopods.  The  flies  of  Asilidae  and 
Tabanidae  are  so  very  distinct  that  these  resemblances  between 
their  larvae  are  worthy  of  note. 

Fam.  25.  Apioceridae. — Modercete-sized  flies  marked  with  Hack 
and  white,  with  an  appearance  like  that  of  some  Muscidae  and 
Asilidae;  with  <-leur  -tn'n;/s,  the  veins  not  deeply  coloured  ;  antennae 
short,  with  a  short,  simple  appemloge  ;  no  empofli  inn.  But  little 
is  known  as  to  the  flies  of  this  family,  of  which  only  two  genera, 
consisting  of  about  a  dozen  species,  are  found  in  North  America, 
Chili,  and  Australia.  Osten  Sacken  is  inclined  to  treat  them 
as  an  aberrant  division  of  Asilidae.  Brauer  looks  on  them  as 
primitive  or  synthetic  forms  of  much  interest,  and  has  briefly 
described  a  larva  which  he  considers  m;iy  be  that  of  A])iocera, 
but  this  is  doubtful ;  it  is  a  twenty-segmented  form,  and  ma}'  be 
that  of  a  Thereva.2 

Fam.  26.  Empidae. — Small  or  moderate-sized  flics  of  olscure 
colours,  grey,  rust//,  o/-  lilaek,  with  small  head,  somewhat  globular 
in  form,  witli  three-jointed  antennae,  the  terminal  joint  Ion//  and 
pointed, ;  usually  there  is  a  long  slender  beak ;  the  legs  arc  elongate, 
/ reticently  hairy ;  Hie  tarxi  hear  long  pulrilli  and  a  small  em- 
l>oa"mni.  The  Empidae  are  an  extensive  family  of  flies,  with 
predaceous  habits,  the  rostrum  1  icing  used  by  the  female  as 
an  instrument  for  impaling  and  sucking  other  flies.  They  are 
occasionally  very  numerous  in  individuals,  especially  in  wooded 
districts.  There  is  great  variety  ;  there  are  nearly  200  species 
in  Britain.  The  forms  placed  in  the  sub-family  Hybotinae  are 
curious  slender  little  Insects,  with  very  convex  thorax  and 

1   Ann.  Sue.  cut.  France  (4)  x.  1870,  p.  221.          -  XJJ.  Ak.    11'tcn,  xci.  18S.">,  p.  392. 


vii  EMPIDAE DOLICHOPIDAE  493 


large  hind  legs.  In  Hemcrodromia  the  front  legs  are  raptorial, 
the  femora  being  armed  with  spines  on  which  the  tibiae 
close  so  as  to  form  a  sort  of  trap.  Many  Empidae  execute 
aerial 'dances,  and  some  of  the  species  of  the  genus  Hilara,  are 
notorious  for  carrying  veils  or  nets  in  the  form  of  silken  webs 
more  or  less  densely  woven.  This  subject  is  comparatively  new, 
the  fact  having  been  discovered  by  Baron  Osten  Sac-ken  in 
1S77,1  and  it  is  not  at  all  clear  what  purpose  these  peculiar 
constructions  serve ;  it  appears  probable  that  they  are  carried 
by  means  of  the  hind  legs,  and  only  by  the  males.  Mik  thinks 
that  in  H.  sartor  the  veil  acts  as  a  sort  of  parachute,  and  is  of 
use  in  carrying  on  the  aerial  performance,  or  enhancing  its 
effect ;  while  in  the  case  of  other  species,  H.  maura  and  H.  inter- 
stincta,  the  object  appears  to  be  the  capture  or  retention  of  prey, 
after  the  manner  of  spiders.  The  source  of  the  silk  is  not 
known,  and  in  fact  all  the  details  are  insufficiently  ascertained. 
The  larvae  of  Empidae  are  described  as  cylindrical  maggots,  with 
very  small  head,  and  imperfect  ventral  feet ;  the  stigmata  are 
amphipneustic,  the  thoracic  pair  being,  however,  excessively 
small ;  beneath  the  posterior  pair  there  is  nearly  always  a  tooth- 
or  spine-like  prominence  present. 

Fam.  27.  Dolichopidae. — Graceful  flies  of  metallic  colours, 
of  moderate  or  small  size,  and  long  legs ;  usually  with  bristles  on  the 
fiiorax  and  legs,  the  h  alter es  exposed,  squamae 
being  quite  absent ;  antennae  of  two  short  stout 
joints  (of  which  the  second  is  really  two,  its 
t/irision  being  more  or  less  distinct),  ivith  a 
tli read-like  or  hair-like  appendage.  Proboscis 
sltort,  fleshy.  Claws,  pulvilli,  and  empodium 
small ;  wings  with  a  simple  system  of  nervures, 
those  on  the  posterior  part  of  the  wing  are  but 
few,  there  is  no  anterior  basal  cross-vein  be- 
the  disced  and  second  basal  cells,  which 


therefore  form   but   one    cell.      This    is    also   a     \23p5u~A;,f  ^ 
very    extensive   family   of  flies,   of  which    we  i:i>if,i://>n.<. 

1  i     i  i          i  T>    -,     •  France.        (After 

have  probably  about    200   species   in   Britain.        pems) 

They    are    conspicuous    on    account    of    their 

golden,  or  golden-green  colours,  only  a  few  being  yellow  or  black. 

1  Ent.  Mag.  xiv.  1877,  p.  226  ;  for  a  discussion  of  the  subject  see  Mik,   Wien. 
cnt.  Zeit.  xiii.  1894,  p.  273. 


494  DIPTERA  CHAP. 

The  males  are  remarkable  for  the  curious  special  characters  they 
possess  on  the  feet,  antennae,  face,  or  wings.  These  characters 
are  not  alike  in  any  two  species  ;  they  are  believed,  to  be  of  the 
nature  of  ornaments,  and  according  to  Professor  Aldrich  and  others 
are  used  as  such  in  courtship.1  This  family  of  Hies  approaches 
very  closely  to  some  of  the  Acalyptrate  Muscidae  in  its  char- 
acters. It  is  united  by  Brauer  with  Empidae  to  form  the  tribe 
Orthogenya.  Although  the  species  are  so  numerous  and 
abundant  in  Europe,  little  is  known  as  to  their  metamorphoses. 
Some  of  the  larvae  frequent  trees,  living  under  the  bark  or  in 
the  overflowing  sap,  and  are  believed  to  be  carnivorous  ;  they  are 
amphipneustic  ;  a  cocoon  is  formed,  and  the  pupa  is  remark- 
able on  account  of  the  existence  of  two  long  horns,  bearing  the 
spiracles,  on  the  back  of  the  thorax  ;  the  seven  pairs  of  abdominal 
spiracles  being  excessively  minute.2 

Series  3.  Cyclorrhapha  Aschiza 

Fam.  28.  Phoridae.  —  Small  flies,  with  rcrtj  convex  thorax, 
xmall  head,  very  small  twa-jointed  antennae,  licm-iny  a  long  seta  ; 
/'<  mora  -more  or  less  broad;  wings  with  two  dark,  thick,  approxi- 
mate veins,  'incc/i/ig  on  the  front  margin  near  its  middle,  and 
besides  these,  tltrcc  or  four  r<'ri/  jinc  veins,  tliat  run  fo  f/ie  margins 
in  a  sub-parallel  manner  without  forming  </////  cells  or  forks.  This 
obscure  family  of  flies  is  of  small  extent,  but  its  members  are  ex- 

tremely common  in  Europe  and  Xorth 
America,  where  they  often  occur  in 
numbers  running  on  the  windows  of 
1  louses.  It  is  one  of  the  most  isolated 
•joe.—  Wing  of  Trineura  groups  of  Diptera,  and  great  difference 


one  of  the  Phor-   of    ui,ini,m    prevails   as   to   its   classifica- 

idae.     Britain.  .  . 

tion.      Ihe  wing-nervuration   is  peculiar 

(but  varies  somewhat  in  the  species),  the  total  absence  of 
any  cross-veins  even  on  the  basal  part  of  the  wing  being 
remarkable.  There  are  bristles  on  the  head  and  thorax,  but 
they  are  not  arranged  in  a  regular  manner.  The  larvae 
live  in  a  great  variety  of  animal  and  vegetable  decaying  matter, 

1  Am,  r.  \uii/rul.  xxviii.  1894,  p.  35. 

-   IVrri>,  Ann.  Soc.  ent.  /''ranee  (4)  x.  1870,   p.  321,  pi.  4  ;   ami  Laboulbene,  op. 
cit.  (5)  iii.  1S73,  p.  W,  pi.  v. 


VII 


PHORIDAE 


495 


and  attack  living  Insects,  and  even  snails,  though  probably 
only  when  these  are  in  a  sickly  or  diseased  condition.  The 
metamorphoses  of  several  species  have  been  described.1  The 
larvae  are  rather  slender,  but  sub-conical  in  form,  with  eleven 
segments  and  a  very  small  head,  amphipneustic,  the  body  behind 
terminated  by  some  pointed  processes.  The  pupa  is  remarkable ; 
it  is  contained  in  a  case  formed  by  the  contracted  and  hardened 
skin  of  the  larva ;  though  it  differs  much  in  form  from  the 
larva  the  segmentation  is  distinct,  and  from  the  fourth  segment 
there  project  two  slender  processes.  These  are  breathing  organs, 
a  ttached  to  the  prothorax  of  the  imprisoned  pupa ;  in  what 
manner  they  effect  a  passage  through  the  hardened  larval  skin 
is  by  no  means  clear.  Ferris  supposes  that  holes  for  them 
pre-exist  in  the  larval  skin,  and  that  the  newly-formed  pupa  by 
restless  movements  succeeds  in  bringing  the  processes  into  such  a 
position  that  they  can  pass  through  the  holes.  The  dehisceiice 
of  the  puparium  seems  to  occur  in 
a  somewhat  irregular  manner,  as 
in  Microdon ;  it  is  never  Cyclor- 
rliaphous,  and  according  to  Ferris 
is  occasionally  Orthorrhaphous  ; 
probably  there  is  no  ptilinum. 

The  Insect  recently  described  by 
Meinert  as  Aenigmatias  llaUoides? 
is  so  anomalous,  and  so  little  is 
known  about  it,  that  it  cannot  at 
present  be  classified.  It  is  com- 
pletely apterous ;  the  arrangement 
of  the  body-segments  is  unlike  that 
of  Diptera,  but  the  antennae  and 
mouth-parts  are  said  to  be  like  those  of  Fhoridae.  The  Insect 
was  found  near  Copenhagen  under  a  stone  in  the  runs  of  Formica 
f  !>*<•</.  Meinert  thinks  it  possible  that  the  discovery  of  the 
male  may  prove  Aenigmatias  to  be  really  allied  to  Phoridae, 
and  Mik  suggests  that  it  may  be  the  same  as  Plat.ypln>r«  lul>l<><-L-'i, 
Yerrall,  known  to  be  parasitic  on  ants.  Dahl  recently  described 
a  wingless  Dipteron,  found  living  as  a  parasite  on  land-snails  in 
the  Bismarck  archipelago,  under  the  name  of  Puliciphora  lucif<  ra, 

1   Penis,  Ann.  Soc.  ent.  France  (4)  x.  1870,  p.  354. 
-  Ent.  Mcdddehcr,  ii.  1890,  p.  21:;. 


496 


DIPTERA 


CHAP. 


and  Wandolleck  has  recently  made  fur  this  and  some  allies  the 
new  family  Stethopathidae.  It  seems  doubtful  whether  these 
forms  are  more  than  wingless  Phoridae. 

Fam.  29.  Platypezidae. — Xttiall  flies,  with  porrect  three- 
jointed  antennae,  first  ttco  joints  short,  third  longer,  -with  a 
ti'i'minal  seta  ;  no  bristles  on  the  bark ;  hind  leas  of  male,  or  of 
both  sexes,  with  peculiar,  broad,  flat  tarsi ;  the  middle  tibiae  bear 
spurs;  there  is  no  empodium.  Platypezidae  is  a  small  family 
of  flies,  the  classification  of  which  has  always  been  a  matter  <>f 
considerable  difficulty,  and  is  still  uncertain.  The  larvae  are 
broad  and  flat,  fringed  at  the  margin  with  twenty-six  spines  ;  they 
live  between  the  lamellae  of  Agaric  fungi.  At  pupation  the  form 
alters  but  little  ;  the  imago  emerges  by  a  horizontal  cleft  occumiii>- 

O  O  v  O 

at  the  margins  of  segments  two  and  four.1  AVe  have  four  genera 
(Opetia,  PI  aty  enema,  Platypeza,  Callomyia),  and  nearly  a  score  of 
species  of  Platypezidae  in  our  British  list,  but  very  little  seems  to 
be  known  about  them.  There  is  much  difference  in  the  eyes  of 
the  sexes,  in  some  at  any  rate  of  the  species,  they  being  large  and 
contiguous  in  the  male,  but  widely  separated  in  the  female. 

Fam.  30.  Pipunculidae." — Small  flic*,  •/>•////  very  short  antennae 

bearing  a,  long  seta   that    is   not   terminal  ;   In'ad   a/mnxf  globular, 

formed,  except  at   the  back,  almost   entirely  by  the  large  conjoined 

eyes;    the    head   is   only  slightly   small,  /•    ///    tin-,  female,   but    in, 

the    male   the   eyes  are   more  approximate   at   the   top.       This    is 

another  of  the  small  fami- 
lies of  flies,  that  seems  dis- 


tinct from  any  other,  though 
possessing  no  very  im- 
portant characters.  In  many 
of  the  flies  that  have  very 
large  eyes,  the  head  is 

FIG.  238.— HeadofPi>mcMZMssp.  A,  Seen  from  either  flattened  (i.e.  coin- 
in  front;  B,  side  view,  showing  an  autenua  pressed  from  before  back- 
magnified.  Pyrenees. 

wards,    as     in     Tabanidae, 

Asilidae),  or  forced  beneath  the  humped  thorax  (as  in  Acro- 
ceridae),  but  neither  of  these  conditions  exists  in  Pipunculus ; 
in  them  the  head  extends  far  forwards,  so  that  the  area  of  the 

1  FniuenfY-ld,  1'cr/i.  Ges.   Wien,  xx.  p.  37,  pi.  iii. 

2  For  monograph  of  Pipunculidae,   see  Becker,  Berlin,  cnt.  Zeltsclir.  xlii.  1897, 
pp.  25-100. 


vii  PIPUNCULIDAE--CONOPIDAE  497 

eye  compared  with  the  size  of  the  body  is  perhaps  greater  than 
in  any  other  Diptera.  The  general  form  is  somewhat  that  of 
Anthrax,  hut  the  venation  on  the  hind  part  of  the  wing  is  much 
less  complex.  There  is  a  remarkable  difference  between  the  facets 
on  the  front  and  the  back  of  these  great  eyes.  We  have  three 
genera  and  about  a  dozen  species  of  Pipunculidae  in  Britain  but 
apparently  they  are  far  from  common  Insects.  "What  is  known 
about  the  life-history  is  almost  confined  to  an  imperfect  observa- 
tion by  Boheman,  who  found  the  larva  of  P.  Justices  living  after 
the  manner  of  a  Hymenopterous  parasite  in  the  body  of  a  small 
Homopterous  Insect.1  The  pupa  seems  to  be  of  the  type  of  that 
of  Syrphidae. 

Fam.  31.  Conopidae. — Elegant  flies  of  moderate  size,  of  varied 
colours,  with  abdomen  slender  at  the  base,  at  the  tip  strongly 
iiii'urrcd  and  thicker;  antennae  inserted  close  together  on  a 
in'oiiii  ncnce,  three -jointed,  first  joint  sometimes  very  short.  TJte 
ujiper  surjace  of  the  body  without  bristles  or  iritli  but  fev:.  There 
is  a  slender,  elongate  proboscis,  ivhich  is  retractile  and  usually 
in  risible.  This  rather  small  family  of  flies  includes  some  of  the 
most  remarkable  forms  of  Diptera ;  it  includes  two  divisions, 
the  Conopinae  with  long  antennae  terminated  by  a  very  minute 
pointed  process,  and  Myopinae  with  shorter  antennae  bearing  a 
hair  that  is  not  placed  at  the  end  of  the  third  joint.  The 
former  are  the  more  wasp-like  and  elegant ;  the  Myopinae  being 
much  more  like  ordinary  flies,  though  they  frequently  have 
curious,  inflated  heads,  with  a  white  face.  The  mode  of  life  of 
the  larva  of  Conops  is  peculiar,  it  being  parasitic  in  the  interior 
of  Bombus,  or  other  Hymenoptera.  They  have  been  found  to 
attack  Bombus,  Chalicodoma,  Osmia,  Vespa,  Pompilus,  and  other 
Aculeates.  Williston  says  that  Orthoptera  are  also  attacked. 
Conops  has  been  seen  to  follow  Bumble-bees  and  alight  on  them, 
and  Williston  says  this  act  is  accompanied  by  oviposition,  the 
larva  that  is  hatched  boring  its  way  into  the  body  of  the  bee. 
Others  have  supposed  that  the  flies  enter  the  bees'  nests  and 
place  their  eggs  in  the  larvae  or  pupae  ;  but  this  is  uncertain,  for 
Conops  has  never  been  reared  from  a  bee-larva  or  pupa,  though 
it  has  frequently  been  procured  from  the  imago  :  cases  indeed 
having  been  recorded  in  which  Conops  has  emerged  from  the  body 

1  Ofv.  Ak.  Fork.  xi.  1854,  p.  302,  pi.  v.,  siiice  confirmed  by  others,  see  Giard, 
C.R.  Ac.  Sci.  cix.  1889,  pp.  79  and  708. 

VOL.  VI  2  K 


498  DIPTERA 


CHAP. 


of  a  Boiiibus  several  months  after  the  latter  had  been  killed  and 
placed  in  an  entomologist's  collection.  The  larva  is  broad,  and 
when  full  grown  apparently  occupies  nearly  all  the  space  of 
the  interior  of  the  abdomen  of  the  bee ;  it  has  very  peculiar 
terminal  stigmata.  The  pupa  is  formed  in  the  larval  skin, 
which  is  greatly  shortened  and  indurated  for  the  purpose  ;  this 
instar  bears,  in  addition  to  the  posterior  stigmata,  a  pair  of 
slightly  projecting,  anterior  stigmata.  We  have  several  species 
of  Conopidae  in  Britain ;  those  belonging  to  the  division 
Conopinae  are  all  rare  Insects,  but  the  Myopinae  are  not  so 
scarce ;  these  latter  are  believed  to  lie  of  similar  habits  with 
the  Conopinae,  though  remarkably  little  is  known  about  them. 
This  is  another  of  the  numerous  families,  the  relations  of  which 
are  still  a  subject  for  elucidation.  Brauer  places  the  Conopidae  in 
his  section  Schizophora  away  from  Syrphidae,  but  we  do  not  com- 
prehend on  what  grounds ;  an  inspection  of  the  head  shows  that 
there  is  no  frontal  lunule  as  there  is  in  Eumyiidae ;  both  Myopa  and 
Conops  agreeing  fairly  well  with  Syrphus  as  to  this.  We  therefore 
place  the  family  in  its  old  position  near  Syrphus  till  the  relations 
with  Acalypterate  Muscidae  shall  be  better  established. 

Fam.  32.  Syrphidae  (Hover -flics}. — Of  moderate  or  rather 
ff> /'i/c  *h./',  frequently  spotted  or  banded  with  yellow,  with  a  thick 
fleshy  proboscis  capable  of  being  withdrawn  into  a  cleft  on  the 
///n/cr  side  of  the  head;  antennae  not  placed  in  deflnite  cavities, 
three-jointed  (usually  very  short],  and  leaving  a  seta  that  is  not 
terminal  in  position,  and  may  be  feathered.  Squama  variable,  never 
entirely  covering  the  haltercs;  the  chief  (third  to  fifth}  longitudinal 
veins  of  the  wings  connected  near  their  termination  by  cross-veins 
and  usually  thus  forming  a  sort  of  short  margin  parallel  with  the 
hind  edy.  of  the  wing ;  a  more  or  less  imperfect  false  nervure  run- 
//.///.//  between  the  third  and  fourth  longitudinal  nervures  ;  no  cm- 
podium  and  generally  no  distinct  system  of  bristles  on  the  back  of 
the  body.  The  Syrphidae  (Fig.  212)  form  one  of  the  largest  ;ind 
best  known  of  all  the  families  of  nies  ;  they  abound  in  our  gardens 
where,  in  sunny  weather,  some  species  may  be  nearly  always 
seen  hovering  over  flowers,  or  beneath  trees  in  places  where  the 
rays  of  the  sun  penetrate  amidst  the  shade.  There  are  two  or 
three  thousand  species  known,  so  that  of  course  much  variety 
exists;  some  are  densely  covered  with  hair  (certain  Volucella  and 
others),  many  are  of  elegant  form,  and  some  bear  a  consider- 


vii  SYRPHIDAE HOVER-FLIES  499 

able    resemblance    to    Hymenoptera    of   various    groups.       The 
peculiar  reining  of  the  wings  permits  of  their  easy  identification, 
the  line  of  two  nerrules,  approximately  parallel  with  the  margin 
of  the  distal  part  of  the  wing  (Fig.  212,  D),  and  followed  by  a  deep 
bay,  being  eminently  characteristic,  though  there  are  some  excep- 
tions; there  are  a  few  forms  in  which  the  antennae  are  exceptional 
in   hariug  a   terminal   pointed   process.      The   proboscis,   besides 
the  membranous  and  fleshy  lips,  consists  of  a  series  of  pointed 
slender  lancets,  the  use  of  which  it  is  difficult  to  comprehend,  as 
the  Insects  are  not  knowTii  to  pierce  either  animals  or  regetables, 
their  food  being  chiefly  pollen  ;  honey  is  also  doubtless   taken 
by    some    species,    but    the    lancet -like    organs    appear    equally 
ill -adapted    for    dealing    with    it.       The    larrae    are    singularly 
diversified  ;   first,   there  are  the  eaters  of  Aphidae,  or  green-fly ; 
some  of  these  may  be  generally  found  on  our   rose-bushes  or  on 
thistles,  when  they  are  much  covered  with  Aphids  ;  they  are  soft, 
maggot -like  creatures  with  a  great  capacity  for  changing  their 
shape    and    with    much    power    of  movement,    especially   of  the 
anterior  part   of   the    body,  which  is  stretched   out  and  moved 
about   to   obtain  and  spear  their  prey :   some  of  them  are  very 
transparent,  so  that  the  movements   of  the  internal  organs  and 
their  vivid  colours    can   readily    be    seen  :    like    so  many  other 
carnivorous  Insects,  their  voracity  appears  to  be  insatiable.     The 
larvae   of  many  of   the  ordinary  Hover-flies    are   of  this    kind. 
Ei'istcdis  and  its  allies  are  totally  different,  they  live  in   water 
saturated   with    filth,  or    with    decaying   vegetable    matter    (the 
writer    has    found   many   hundreds   of   the   larvae  of  Myiatropa 
florea  in  a  pool  of  water  standing  in  a  hollow  beech-tree).     These 
rat-tailed  maggots  are  of  great  interest,  but  as  they  have  been 
described  in   almost  every  work  on  entomology,  and  as  Professor 
Miall T   has  recently  given  an  excellent  account  of  their  pecu- 
liarities, we  need   not   now  discuss   them.      Some  of  the  flies  of 
the  genus  Eristalis  are  very  like  honey-bees,  and  appear  in  old 
times  to  have  been  confounded  with  them  ;  indeed,  Osten  Sacken 
thinks    this    resemblance   gave   rise   to   the  "  Bugonia  myth,"  a 
fable  of  very  ancient  origin  to  the  effect   that  Honey-bees  could 
be  procured  from  filth,  or  even  putrefying  carcases,  by  the  aid  of 
certain    proceedings    that    savoured    slightly    of   witchcraft,   and 
may  therefore   have  increased   the   belief  of  the  operator  in  the 

1  Natural  History  of  Aquatic  Insects,  1895,  p.  198. 


500  DIPTERA  CHAP. 

possibility  of  a  favourable  result.  It  was  certainly  not  bees  that 
were  produced  from  the  carcases,  but  Osten  Sacken  suggests  that 
Jflristalis-Qies  may  have  heen  bred  therein. 

In  the  genus  Volucclla  we  meet  with  a  third  kind  of  Syrphid 
larva.  These  larvae  are  pallid,  broad  and  fleshy,  surrounded  by 
numerous  angular,  somewhat  spinose,  outgrowths  of  the  body ; 
and  have  behind  a  pair  of  combined  stigmata,  in  the  neighbour- 
hood of  which  the  outgrowths  are  somewhat  larger ;  these  larvae 
live  in  the  nests  of  Bees  and  Wasps,  in  which  they  are  abundant. 
Some  of  the  Volucdla,  like  many  other  Syrphidae,  bear  a  con- 
siderable resemblance  to  Bees  or  Wasps,  and  this  has  given  rise  to 
a  modern  fable  about  them  that  appears  to  have  no  more  legiti- 
mate basis  of  fact  than  the  ancient  Bees-born-of-carcases  myth. 
It  was  formerly  assumed  that  the  Volucella-lsHiVae  lived  on  the 
larvae  of  the  Bees,  and  that  the  parent  Hies  were  providentially 
endowed  with  a  bee -like  appearance  that  they  might  obtain 
entrance  into  the  Bees'  nests  without  being  detected,  and  then 
carry  out  their  nefarious  intention  of  laying  eggs  that  would 
hatch  into  larvae  and  subsequently  destroy  the  larvae  of  the  Bees. 
Some  hard-hearted  critic  remarked  that  it  was  easy  to  understand 
that  providence  should  display  so  great  a  solicitude  for  the  welfare 
of  the  Volucclla,  but  that  it  was  difficult  to  comprehend  how  it 
could  be,  at  the  same  time,  so  totally  indifferent  to  the  welfare  of 
the  Bees.  More  recently  the  tale  has  been  revived  and  cited  as 
an  instance  of  the  value  of  deceptive  resemblance  resulting  from 
the  action  of  natural  selection,  without  reference  to  providence. 
There  are,  however,  no  facts  to  support  any  theory  on  the  subject. 
Very  little  indeed  is  actually  known  as  to  the  habits  of  7W//- 
cella  in  either  the  larval  or  imaginal  instars;  but  the  little  that 
is  known  tends  to  the  view  that  the  presence  of  the  Volucella 
in  the  nests  is  advantageous  to  both  Fly  and  Bee.  Nicolas  has 
seen  Volucella  zoncvria  enter  the  nest  of  a  Wasp  ;  it  settled  at  a 
little  distance  and  walked  in  without  any  fuss  being  made.  Erne 
has  watched  the  Volucella-\(\i-\  ae  in  the  nests,  and  he  thinks  that 
they  eat  the  waste  or  dejections  of  the  larvae.  The  writer  kept 
under  observation  Volucella-liiTvae  and  portions  of  the  cells  of 
Hi'iiilms,  containing  some  larvae  and  pupae  of  the  Bees  and  some 
honey,  but  the  fly-larvae  did  not  during  some  weeks  touch  any  of 
the  I'x-cs  or  honey,  and  ultimately  died,  presumably  of  starvation. 
Subsequently,  he  experimented  \\  ith  Volucella-la,rva,e  and  a  portion 


vii  SYRPHIDAE HOVER-FLIES  50  I 

of  the  comb  of  wasps  containing  pupae,  and  again  found  that  the 
flies  did  not  attack  the  Hymenoptera  ;  but  on  breaking  a  pupa 
of  the  Wasp  in  two,  the  fly-larvae  attacked  it  immediately  and 
eagerly ;  so  that  the  evidence  goes  to  show  that  the  Volucella- 
larvae  act  as  scavengers  in  the  nests  of  the  Hymenoptera. 
Kiinckel  d'Herculais  has  published  an  elaborate  work  on  the 
European  Voluccllu ;  it  is  remarkable  for  the  beauty  of  the 
plates  illustrating  the  structure,  anatomy  and  development,  but 
throws  little  direct  light  on  the  natural  history  of  the  Insects. 
V.  lomli/Ians,  one  of  the  most  abundant  of  our  British  species, 
appears  in  two  forms,  each  of  which  has  a  considerable  resem- 
blance to  a  Boinbus,  and  it  has  been  supposed  that  each  of  the 
two  forms  is  specially  connected  with  the  Bee  it  resembles,  but 
there  is  no  evidence  to  support  this  idea  ;  indeed,  there  is  some 
little  evidence  to  the  contrary.  The  genus  Merodon  has  larvae 
somewhat  similar  to  those  of  VolucMa,  but  they  live  in  bulbs 
of  Narcissus;  M.  equestris  has  been  the  cause  of  much  loss  to  the 
growers  of  Dutch  bulbs  ;  this  Fly  is  interesting  on  account  of  its 
great  variation  in  colour  ;  it  has  been  described  as  a  whole  series 
of  distinct  species. 

The  most  remarkable  of  the  numerous  forms  of  Syrphid  larvae 
are  those  of  the  genus  Microdon  (Fig.  239),  which  live  in  ants' 
nests.  They  have  no  resemblance  to  Insect -larvae,  and  when 
first  discovered  were  not  only  supposed  to  be  little  Molluscs,  but 
were  actually  described  as  such  under  the  generic  names  of 
Parmula  and  Scutelligera.  There  is  no  appearance  of  segmenta- 
tiun  of  the  body;  the  upper  surface  is  covered  by  a  sort  of 
network  formed  by  curved  setae,  which  help  to  retain  a  coating 
of  dirt ;  there  is  no  trace  externally  of  any  head,  but  on  the 
under  surface  there  is  a  minute  fold  in  which  such  mouth-organs 
as  may  1  >e  present  are  probably  concealed ;  the  sides  of  the  body 
project  so  as  to  form  a  complex  fringing  arrangement ;  the  ter- 
minal stigmata  are  very  distinct,  the  lateral  processes  connected 
with  them  (the  "  Knospen  "  of  Dr.  Meijere),  are,  however,  very 
irregular  and  placed  at  some  distance  from  the  stigmatic  scar. 
Pupation  occurs  by  the  induration  of  the  external  covering  and 
the  growth  from  it,  or  rather  through  it,  of  two  short  horns  in 
front.  Inside  this  skin  there  is  formed  a  soft  pupa,  of  the  kind 
usual  in  Cyclorrhaphous  flies ;  the  dehiscence  of  the  external 
covering  is,  however,  of  unusual  nature,  three  little  pieces  being 


502 


DIPT  ERA 


CHAP. 


separated  from  the  anterior  part  of  the  upper  surface,  while  the 
lower  face  remains  intact.  The  account  of  the  pupation  given 
by  Elditt l  is  not  complete:  the  two  horns  that  project  are,  it' 
would  appear,  not  portions  of  the  larval  skin,  hut  belong  to 
the  head  of  the  pupa,  and  according  to  Elditt  are  used  to  effect 
the  dehiscence  of  the  case  for  the  escape  of  the  fly ;  there  does 
not  appear  to  be  any  head-vesicle.  Nothing  is  known  as  to 
the  details  of  the  life  of  these  anomalous  larvae.  M.  Poujade 
has  described  two  species  found  in  France  in  the  nests  of  the 
ant  Lasius  n'nj<  r~~  The  larva  we  figure  was  found  by  Colonel 
Yerbury  in  nests  of  an  Atta  in  Portugal,  and  an  almost  identical 


.r^fe$fi&!MS^ 

:  ?"J(G~'  f  -itf; ?\/M? 
••••^.y^ -  -.;• 

'       .,--././•          t_  r         i»ij  • 


FIG.  239. — Larva  of  Microdon  sp.  Portugal.  A,  Dorsal  view  of  the  larva,  x  4  ;  1, 
the  stijrinatic  structure  ;  B,  posterior  view  of  stigruatic  structure  ;  C,  a  portion  of 
the  marginal  fringe  of  the  body. 

larva  was  recently  found  by  Mr.  Budgett  in  Paraguay.  The 
flies  themselves  are  scarce,  Microdon  mutcibilis  (formerly  called 
J/.  apiformis)  being  one  of  the  rarest  of  British  flies.  They  have 
the  antennae  longer  than  is  usual  in  Syrphidae,  and  the  cross- 
veins  at  the  outside  of  the  wing  are  irregularly  placed,  so  that 
the  contour  is  very  irregular :  the  resemblance  to  bees  is  very 
marked,  and  in  some  of  the  South  American  forms  the  hind  legs 
are  flattened  and  hairy  like  those  of  bees.  The  oviposition  of 
Mi*' ro<l u n  has  been  observed  by  Verhoeff;3  he  noticed  that  the  fly 
was  frequently  driven  away  by  the  ants — in  this  case,  Formica 
*"//f/iiinea — but  returned  undiscouraged  to  its  task. 

A  brief  resume  of  the  diverse  modes  of  life  of  Syrphid  larvae 
fms  been  given  by  Perris,4  and  he  also  gives  some  information  as 
to  the  curious  burns  of  the  pupae,  but  this  latter  point  much 

1  Ent.  Zcit.  Stettin,  vi.  18-15,  p.  384,  pi.  i. 

-  Ann.  Soc.  cnt.  France  (6)  iii.  1883,  p.  23,  pi.  i. 

a  Ent.  Xachr.  xviii.  1892,  p.  13.          4  Ann.  Soc.  cnt.  France  (4)  x.  1870,  p.  330. 


VII 


MUSCIDAE    ACALYPTRATAE 


503 


wants  elucidation.  Whether  the  Syrphidae,  or  some  of  them, 
possess  a  ptilinum  that  helps  them  to  emerge  from  the  pupa  is 
more  than  doubtful,  though  its  existence  has  been  affirmed  by 
several  authors  of  good  repute.1 

Series  4.  Cyclorrhapha  Schizophora 

Fam.  33.  Muscidae  acalyptratae. — This  group  of  flies  has 
been  the  least  studied  of  all  the  Diptera ;  it  is  generally  treated 
as  composed  of  twenty  or  thirty  different  families  distinguished 


FIG.  240. — Diopsis 
apicalis.  Natal. 
A,  The  fly  ;  B,  ex- 
tremity of  cephalic 
protuberance,  more 
magnified.  a, 
The  eye  ;  >>,  the 
antenna;  C,  middle 
of  head,  front 
view  ;  c,  ocelli. 


by  very  slight  characters.  It  is,  however,  generally  admitted  by 
systematists  that  these  assemblages  have  not  the  value  of  the 
families  of  the  other  divisions  of  Diptera,  and  some  even  go  so 
far  as  to  say  that  they  are  altogether  only  equivalent  to  a  single 
family.  We  do  not  therefore  think  it  necessary  to  define  each 
one  seriatim ;  we  shall  merely  mention  their  names,  and  allude 
to  certain  points  of  interest  connected  with  them.  Taken  collec- 
tively they  may  be  defined  as  very  small  flies,  with  three-jointed 
antennae  (frequently  looking  as  if  only  two -jointed},  bearing  a 
bristle  that  is  not  terminally  placed ;  frequently  either  destitute  of 
squamae  or  having  these  imperfectly  developed  so  as  not  to  cover  the 
halteres  ;  and  possessing  a  comparatively  simple  system  of  nervura- 
tion,  tlie  chief  nervures  being  nearly  straight,  so  that  consequent/// 
few  cells  are  formed.  These  characters  will  distinguish  the  group 

1  See  on  this  difficult  subject,  Becher,   U'tcn.  ent.  Zeit.  i.  1882,  p.  49. 


504 


DIPTERA 


CHAP. 


from  all  the   other  Diptera  except   from   forms  of  Aschiza,  and 
from  certain  Anthomyiidae,  with  both  of  which  the  Acalyptratae 
are    really    intimately    connected.        Considerable    difference    of- 
opinion  prevails  as   to    the   number  of  these   divisions,  but  the 
families  usually  recognised  are  :— 


1.  Doryceridae. 

2.  Tetanoceridae. 

3.  Sciomyzidae. 

4.  Diopsidae. 

5.  Celyphidae. 
,,      |  Sepsidae 

(incl.  Piophilidae. 
( Chloropidae 
\(  =  0scinidae). 

8.  Ulidiidae. 

9.  Piatystoniidae. 

10.  Ephydridae. 

11.  Helomyzidae. 


12.  Dryomyzidae. 

13.  Borboridae. 

14.  Pliycodroiuidae. 

15.  Thyreophoridae. 

|  Scatophagidae. 
{_( =  Scatomyzidae). 
/  Geomyzidae 
\_incl.  Opomyzidae. 
f  Drosopliilidae  ; 
^incl.  Asteidae. 
Psilidae. 
|  Tauypezidae 
(( =  Micropezidae). 


16 


17. 


18. 


20. 


21. 
22. 


26. 

27. 
28. 
29. 


Trypetidae. 

|  Sapromyzidae 

(incl.  Lonchaeidae. 
Rhopalomeridae. 
Ortalidae. 

fAgromyzidae 

-!  incl.      Phytomyzi- 

[     dae. 

Milichiidae. 

Octhipliilidae. 

Heteroneuridae. 

Cordyluridae. 


Brauer  associates  Conopidae  with  Acalyptrate  Muscids,  and 
calls  the  Group  Holometopa ;  applying  the  term  Schizometopa 
to  the  Calyptrate  Muscidae. 

iSTo  generalisation  can  yet  be  made  as  to  the  larvae  of  these 
divisions,  neither  can  any  characters  be  pointed  out  by  which 
they  can  be  distinguished  from  the  larvae  of  the  following 
families.  In  their  habits  they  have  nothing  specially  distinctive, 
and  may  be  said  to  resemble  the  Anthomyiidae,  vegetable 
matter  being  more  used  as  food  than  animal ;  many  of  them 
mine  in  the  leaves  or  stems  of  'plants  ;  in  the  genus  Dorycera  the 
larva  is  aquatic,  mining  in  the  leaves  of  \vater-plants,  and  in 
Ephydridae  several  kinds  of  aquatic  larvae  are  found,  some  of 
which  are  said  to  resemble  the  rat-tailed  larvae  of  Syrphidae  ; 
certain  of  these  larvae  occur  in  prodigious  quantities  in  lakes, 
and  the  Insects  in  some  of  their  early  stages  serve  the  Mexicans 
as  food,  the  eggs  being  called  Ahuatle,  the  larvae  Pusci,  the 
pupae  Koo-chah-bee.  Some  of  the  larvae  of  the  Sciomyzidae  are 
also  aquatic :  that  of  Tetanocera  ferruginea  is  said  by  Dufour  to 
consist  only  of  eight  segments,  and  to  be  metapneustic ;  Brauer 
considers  the  Acalyptrate  larvae  to  be,  however,  in  general, 
amphipneustic,  like  those  of  Calyptratae.  The  Chloropidae  are 
a  very  important  family  owing  to  their  occasional  excessive 
multiplication,  and  to  their  living  on  cereals  and  other  grasses, 
various  parts  of  which  they  attack,  sometimes  causing  great  losses 
to  the  agriculturist.  The  species  of  the  genus  Chlorops  are 


VII 


MUSCIDAE    ACALYPTRATAE 


505 


famous  for  the  curious  habit  of  entering  human  habitations  in 
great  swarms  :  frequently  many  millions  being  found  in  a  single 
apartment.  Instances  of  this  habit  have  been  recorded  both  in 
France  and  England,  Cambridge  being  perhaps  the  place  where  the 
phenomenon  is  most  persistently  exhibited.  In  the  year  1831  an 
enormous  swarm  of  C.  lineata  was  found  in  the  Provost's  Lodge 
at  King's  College  and  was  recorded  by  Leonard  Jenyns ;  in 
18*70  another  swarm  occurred  in  the  same  house  if  not  in  the 
same  room.1  Of  late  years  such  swarms  have  occurred  in  certain 
apartments  in  the  Museums  (which  are  not  far  from  King's 
College),  and  always  in  the  same  apartments.  No  clue  whatever 
can  be  obtained  as  to  their  origin  ;  and  the  manner  in  which 
these  flies  are  guided  to  a  small  area  in 
numbers  that  must  be  seen  to  lie  be- 
lieved, is  most  mysterious.  These  swarms 
always  occur  in  the  autumn,  and  it  has 
been  suggested  that  the  individuals  are 
seeking  winter  quarters. 

Several  members  of  the  Acalyptratae 
have  small  wings  or  are  wingless,  as  in 
some  of  our  species  of  Horborus.  The 
Diopsidae — none  of  which  are  European 
—have  the  sides  of  the  head  produced 
into  long  horns,  at  the  extremity  of  which  f, 
are  placed  the  eyes  and  antennae ;  these  '•. 
curiosities  (Fig.  240)  are  apparently  com- 
mon in  both  Hindostan  and  Africa.  In 
the  horned  flies  of  the  genus  Elapliomyia, 
parts  of  the  head  are  prolonged  into 
horns  of  very  diverse  forms  according  to 
the  species,  but  bearin 
great  resemblance  to  miniature 
horns.  A  genus  (Giraffomyia)  with  a  long 
neck,  and  with  partially  segmented  appen- 
dages, instead  of  horns  on  the  head,  has 
been  recently  discovered  by  Dr.  Arthur 
Willey  in  New  Britain.  Equally  remarkable  are  the  species  of 
( 'fly pirns  ;  they  do  not  look  like  flies  at  all,  owing  to  the  scutellum 
being  inflated  and  enlarged  so  as  to  cover  all  the  posterior  parts 

1  London 's  Mwj«~iiu:.  v.  1832,  p.  302  ;  P.  cut.  Soc.  London,  1871,  p.  x. 


ig  on   the  whole   a 


stag- 


FIG.    241.— ( 

celyphus)  sp.  West  Africa. 
A,  The  fly  seen  from 
above  ;  a,  scutellum  ;  b, 
base  of  wing :  B,  proliK 
with  tip  of  abdomen  bent 
downwards ;  a,  scutellum  ; 
b,  6,  wing  ;  c,  part  ot 
abdomen. 


506  DIPTERA 


CHAP. 


of  the  body  as  in  the  Scutellerid  Hemiptera  :  the  wings  are 
entirely  concealed,  and  the  abdomen  is  reduced  to  a  plate,  with 
its  oritice  beneath,  not  terminal ;  the  surface  of  the  body  is 
highly  polished  and  destitute  of  bristles.  Whether  this  is  a 
mimetic  form,  occurring  in  association  with  similar -looking 
Bugs  is  not  known.  The  North  American  genus  Toxotrypana 
is  furnished  witli  a  long  ovipositor ;  and  in  this  and  in  the  shape 
of  the  body  resembles  the  parasitic  Hymen  optera.  This  genus 
wTas  placed  by  Gerstaecker  in  Ortalidae,  but  is  considered  by 
later  writers  to  be  a  member  of  the  Trypetidae.  This  latter 
family  is  of  considerable  extent,  and  is  remarkable  amongst  the 
Diptera  for  the  way  in  which  the  wings  of  many  of  its  members 
are  ornamented  by  an  elaborate  system  of  spots  or  marks,  vary- 
ing according  to  the  species. 

Fam.  34.  Anthomyiidae. — Flics  similar  in  appearance  to 
the  House-fly  ;  the  main  vein  posterior  to  the  middle  of  the  wing 
(4fh  longitudinal)  continued  straight  to  the  margin,  not  turned 
upwards.  Eyes  of  the  male  frequently  A//y/''  "><<!•  contiguous, 
bristle  of  antenna  cither  feathery  or  bare.  This  very  large  family 
of  flies  is  one  of  the  most  difficult  and  unattractive  of  the  Order. 
Many  of  its  members  come  close  to  the  Acalyptrate  Muscidae 
from  which  they  are  distinguished  by  the  fact  that  a  well- 
developed  squama  covers  the  halteres  ;  others  come  quite  as 
close  to  the  Tachinidae,  Muscidae  and  Sarcophagidae,  but  may 
readily  be  separated  by  the  simple,  not  augulate,  main  vein 
of  the  wing.  The  larval  habits  are  varied.  Many  attack 
vegetables,  produce  disintegration  in  them,  thus  facilitating  de- 
composition. Anthomyia  brassieae  is  renowned  amongst  market 
gardeners  on  account  of  its  destructive  habits.  A.  cana,  on  the 
contrary,  is  beneficial  by  destroying  the  migratory  Locust 
Schistocerca  peregrina ;  and  in  North  America,  A.  angustifrons 
performs  a  similar  office  with  Caloptenus  spretus.  One  or  two 
species  have  been  found  living  in  birds;  in  one  case  on  the  head  of 
a  species  of  Spermoph  ila,  in  another  case  on  a  tumour  of  the  wing 
of  a  Woodpecker.  Hylemyia  strignxo,  a  dung-frequenting  species, 
has  the  peculiar  habit  of  producing  living  larvae,  one  at  a  time  ; 
these  larvae  are  so  large  that  it  would  be  supposed  they  are  full 
grown,  but  this  is  not  the  case,  they  are  really  only  in  the  first 
st,-ige,  an  unusual  amount  of  growth  being  accomplished  in  this 
stadium.  Spilogaster  <niyeUcae,  on  the  other  hand,  according  to 


VII 


ANTHOMYIIDAE TACHINIDAE 


507 


Portschinsky,  lays  a  small  number  of  very  large  eggs,  and  the  result- 
ing larvae  pass  from  the  first  to  the  third  stage  of  development, 
omitting  the  second  stage  that  is  usual  in  Eumyiid  Muscidae.1 

Fam.  35.  Tachinidae. — First  posterior  cell  of  wing  nearly  or 
quite  closed.  Squamae  large,  covering  the  halteres  :  antennal  arista 
•  bare  :  upper  surface  of  body  usually  bristly.  This  is  an  enormous 
family  of  flies,  the  larvae  of  which  live  parasitic-ally  in  other  living 
Insects,  Lepidopterous  larvae  being  especially  haunted.  Many 
have  been  reared  from  the  Insects  in  which  they  live,  but  beyond 
this  little  is  known  of  the  life-histories, and  still  less  of  the  structure 
of  the  larvae  of  the  Tachinidae,  although  these  Insects  are  of  the 
very  first  importance  in  the  economy  of  Nature.  The  eggs  are 
usually  deposited  by  the  parent-Hies  near  or  on  the  head  of  the 


FIG.  242. —  Ugimyia  sericariae.  A.  The  perfect  fly,  x  2  ;  B,  tracheal  chamber  of  a  silk- 
worm, with  body  of  a  larva  of  Ugimyia  projecting;  a,  front  part  of  the  maggot  ; 
b,  stigmatic  orifice  of  the  maggot ;  c,  stigma  of  the  silkworm.  (After  Sasaki.) 

victim ;  Riley  supposed  that  the  fly  buzzes  about  the  victim  and 
deposits  an  egg  with  rapidity,  but  a  circumstantial  account  given 
by  Weeks2  discloses  a  very  different  process:  the. fly  he  watched 
sat  on  a  leaf  quietly  facing  a  caterpillar  of  Da  tana  engaged  in 
feeding  at  a  distance  of  rather  less  than  a  quarter  of  an  inch. 
"  Seizing  a  moment  when  the  head  of  the  larva  was  likely 
to  remain  stationary,  the  fly  stealthily  and  rapidly  bent  her 
abdomen  downward  and  extended  from  the  last  segment  what 
proved  to  be  an  ovipositor.  This  passed  forward  beneath  her 
body  and  between  the  legs  until  it  projected  beyond  and  nearly 
on  a  level  with  the  head  of  the  fly  and  came  in  contact  with  the 
eye  of  the  larva  upon  which  an  egg  was  deposited,"  making  an 
addition  to  five  already  there.  Ugimyia  sericariae  does  great 

1  Baron  von  Osten  Sacken  informs  the  writer  that  this  statement  has  since  been 
withdrawn  by  Portschinsky  as  being  erroneous. 

2  Ent.  Amcr.  iii.  1887,  p.  126. 


5o8 


DIPTERA 


CHAP. 


harm  in  Japan  by  attacking  the  silkworm,  and  in  the  case  of  this 
tiy  the  eggs  are  believed  to  be  introduced  into  the  victim  by 
being  laid  on  mulberry  leaves  and  swallowed  with  the  food'; 
several  observers  agree  as  to  the  eggs  being  laid  on  the  leaves,  but 
the  fact  that  they  are  swallowed  by  the  silkworm  is  not  so  certain. 
Sasaki  has  given  an  extremely  interesting  account  of  the  develop- 
ment of  this  larva.1  According  to  him,  the  young  larva,  after 
hatching  in  the  alimentary  canal,  bores  through  it,  and  enters  a 
nerve-ganglion,  feeding  there  for  about  a  week,  after  which  the 
necessity  for  air  becoming  greater,  as  usual  with  larvae,  the 
maggot  leaves  the  nervous  system  and  enters  the  tracheal  system, 
boring  into  a  tube  near  a  stigmatic  orifice  of  the  silkworm,  where 
it  forms  a  chamber  for  itself  by  biting  portions  of  the  tissues  and 
fastening  them  together  with  saliva.  In  this  it  completes  its 


FIG.  243. — Diagrammatic  section  of  silkworm  to  show  the  habits  of  Ugimyia.  a,  Young 
larva  ;  b,  egg  of  Uinnii/in  in  stomach  of  the  silkworm  ;  c,  larva  in  a  nerve-ganglion  ; 
if,  larva  entering  a  ganglion  ;  e,  larva  embedded  in  tracheal  chamber,  as  shown  in 
Fig.  242,  B.  (After  Sasaki. ) 

growth,  feeding  on  the  interior  of  the  silkworm  with  its  anterior 
part,  and  breathing  through  the  stigmatic  orifice  of  its  host; 
after  this  it  makes  its  exit  and  buries  itself  deeply  in  the  ground, 
where  it  pupates.  The  work  of  rupturing  the  puparium  by  the 
use  of  the  ptilinum  is  fully  described  by  Sasaki,  and  also  the  fact 
that  the  fly  mounts  to  the  surface  of  the  earth  by  the  aid  of  this  same 
peculiar  air-bladder,  which  is  alternately  contracted  and  distended. 
Five,  or  more,  of  the  Ugimyia- maggots  may  lie  found  in  one 
rattTpillar,  but  only  one  of  them  reaches  maturity,  and  emerges 
from  the  body.  The  Tachinid  flies  appear  to  waste  a  large  pro- 
portion of  their  eggs  by  injudicious  oviposition  ;  but  they  make 
up  for  this  by  the  wide  circle  of  their  victims,  for  a  single  species 
lias  been  known  to  infest  Insects  of  two  or  three  different  Orders. 
The  species  of  Miltogramma — of  which  there  are  many  in 
Europe  and  two  in  England — live  at  the  expense  of  Eossorial 

1  J.  Cull.  Japan,  i.  1886,  pp.  1-46,  plates  i.-vi. 


vii  TACHINIDAE  509 

Hymenoptera  by  a  curious  sort  of  indirect  parasitism.  They  are 
obscure  little  flies,  somewhat  resembling  the  common  House-fly, 
but  they  are  adepts  on  the  wing  and  have  the  art  of  ovipositing 
with  extreme  rapidity  ;  they  follow  a  Hymenopteron  as  it  is  carry- 
ing the  prey  to  the  nest  for  its  young.  When  the  wasp  alights 
on  the  ground  at  the  entrance  to  the  nest,  the  Miltogramma 
swoops  down  and  rapidly  deposits  one  or  more  eggs  on  the  prey 
the  wasp  designs  as  food  for  its  own  young.  Afterwards  the  larvae 
of  the  fly  eat  up  the  food,  and  in  consequence  of  the  greater 
rapidity  of  their  growth,  the  young  of  the  Hymenopteron  perishes. 
Some  of  them  are  said  to  deposit  living  larvae,  not  eggs.  Fabre 
has  drawn  a  very  interesting  picture  of  the  relations  that  exist 
between  a  species  of  Miltogramma  and  a  Fossorial  Wasp  of  the 
genus  Bembcx}  We  may  remind  the  reader  that  this  Hymenop- 
teron has  not  the  art  of  stinging  its  victims  so  as  to  keep  them 
alive,  and  that  it  accordingly  feeds  its  young  by  returning  to 
the  nest  at  proper  intervals  with  a  fresh  supply  of  food,  instead 
of  provisioning  the  nest  once  and  for  all  and  then  closing  it. 
This  Hymenopteron  has  a  habit  of  catching  the  largest  and 
most  active  flies — especially  Tabanidae — for  the  benefit  of  its 
young,  and  it  would  therefore  be  supposed  that  it  would  be  safe 
from  the  parasitism  of  a  small  and  feeble  fly.  On  the  contrary, 
the  Miltogramma  adapts  its  tactics  to  the  special  case,  and  is  in 
liict  aided  in  doing  so  by  the  wasp  itself.  As  if  knowing  that  the 
wasp  will  return  to  the  carefully-closed  nest,  the  Miltogramma 
waits  near  it,  and  quietly  selects  the  favourable  moment,  when 
the  wasp  is  turning  round  to  enter  the  nest  backwards,  and 
deposits  eggs  on  the  prey.  It  appears  from  Fabre's  account  that 
the  Bembex  is  well  aware  of  the  presence  of  the  fly,  and  would 
seem  to  entertain  a  great  dread  of  it,  as  if  conscious  that  it  is  a 
formidable  enemy ;  nevertheless  the  wasp  never  attacks  the 
little  fly,  but  allows  it  sooner  or  later  to  accomplish  its  purpose, 
and  will,  it  appears,  even  continue  to  feed  the  fly-larvae,  though 
they  are  the  certain  destroyers  of  its  own  young,  thus  repeat- 
ing the  relations  between  cuckoo  and  sparrow.  Most  of  us 
think  the  wasp  stupid,  and  find  its  relations  to  the  fly  incredible 
or  contemptible.  Fabre  takes  a  contrary  view,  and  looks  on  it 
as  a  superior  Uncle  Toby.  We  sympathise  with  the  charming- 
French  naturalist,  without  forming  an  opinion. 

1  Souvenirs  entomoloyiques,  1879,  pp.  246-254. 


5  I O  D1PTERA  CHAP. 

Doubtless  there  are  many  other  interesting  features  to  be  found 
in  the  life-histories  of  Tachinidae,  for  in  numbers  they  are  legion. 
It  is  probable  that  we  may  have  200  species  in  Britain,  and  in 
other  parts  of  the  world  they  are  even  more  abundant,  about 
1000  species  being  known  in  North  America.1  The  family 
Actiidae  is  at  present  somewhat  doubtful.  According  to  Karsch,2 
it  is  a  sub-family  of  Tachinidae ;  but  the  fourth  longitudinal 
vein,  it  appears,  is  straight. 

Fam.  36.  Dexiidae. — These  Insects  arc  distinguished  from 
Tachinidae  by  the  bristle  of  the  antennae  'being  pubescent,  and 
the  legs  'usually  longer.  The  larvae,  so  far  as  known,  are  found 
in  various  Insects,  especially  in  Coleoptera,  and  have  also  been 
found  in  snails.  There  are  eleven  British  genera,  and  about  a 
score  of  species. 

Fam.  37.  Sarcophagidae.  -  -  Distinguished  from  Jfuscidae 
and  Tachinidae  by  little  more  than  that  the  bristle  of  the 
antennae  is  feathery  at  the  base  but  hair-like  and  very  jfine  at 
the  ti'p. — Xa-rcophaya  carnaria  is  one  of  the  commonest  British 
Insects;  it  is  like  the  Blow -fly,  though  rather  longer,  con- 
spicuously grey  and  black,  with  the  thorax  distinctly  striped, 
and  the  pulvilli  very  conspicuous  in  the  live  fly.  Cynoinyia 
inortuorum  is  a  bright  blue  ny  rather  larger  than  the  Blow-tiy, 
of  which  it  is  a  competitor ;  but  in  this  country  an  unsuccessful 
one.  The  larvae  of  the  two  Insects  are  found  together,  and  are 
said  to  be  quite  indistinguishable.  Cynomyia  is  said  to  lay  only 
about  half  the  number  of  eggs  that  the  Blow-tiy  does,  but  it 
appears  earlier  in  the  year,  and  to  this  is  attributed  the  fact 
that  it  is  not  altogether  crowded  out  of  existence  by  the  more 
prolific  Calliphora.  The  species  of  Sarcophagidae  are  usually 
viviparous,  and  one  of  them,  Sarcophila  magnijica  (wohlfahrti), 
has  the  habit  of  occasionally  depositing  its  progeny  in  the 
nostrils  of  mammals,  and  even  of  human  1  icings,  causing  horrible 
sufferings  and  occasionally  death  :  it  is  said  to  be  not  uncommon 
in  Europe,  but  does  not  occur  in  Britain.  The  genus  Sarcophaga 
is  numerous  in  species,  and  many  of  them  are  beneficial.  Sir 
Sidney  Saunders  found  in  the  Troad  that  Locusts  were  destroyed 
by  the  larvae  of  a  Sarcophaga  living  in  their  bodies;  and 

1  A  list  of  the;  Insects  known  to  be  attacked  by  Dipterous  parasites  has  Kmi 
given  by  liraucr  and  Bergenstamm,  Dcnk.  Ak.   Jf'icti,  Ixi.  1805. 

2  Berlin,  nit.  Z<  it.  xxx.  1886,  p.  135. 


vii  SARCOPHAGIDAE — MUSCIDAE  5  I  I 

Klinckel  has  recently  observed  that  in  Algeria  several  species 
of  this  genus  attack  Locusts  and  destroy  large  quantities  by 
depositing  living  larvae  in  the  Orthoptera.  In  North  America 
the  Army-worm  is  decimated  by  species  of  Sarco2>/t";/". 

Many  of  these  Insects,  when  food  is  scarce,  eat  their  own 
species  with  eagerness,  and  it  seems  probable  that  this  habit  is 
beneficial  to  the  species.  The  parent-fly  in  such  cases  usually 
deposits  more  eggs  than  there  is  food  for,  thus  ensuring  that 
every  portion  of  the  food  will  be  rapidly  consumed,  after  which 
the  partially-grown  larvae  complete  their  development  by  the 
aid  of  cannibalism.  It  is  thus  ensured  that  the  food  will  raise 
up  as  many  individuals  as  possible. 

Fam.  38.  Muscidae. — Bristle  of  antennae  feathered.  This 
family  contains  many  of  the  most  abundant  flies,  including  the 
House-fly,  Blue -bottles  or  Blow -flies,  Green -bottles,  and  other 
forms  which,  though  very  common,  are  perhaps  not  dis- 
criminated from  one  another  by  those  who  are  not  entomologists. 
The  larvae  live  on  carrion  and  decaying  or  excrementitious 
matters.  The  comm on' House-fly,  Musca  domestica,  runs  through 
its  life-history  in  a  very  short  time.  It  lays  about  150  very  small 
eggs  on  dung  or  any  kind  of  soft  damp  filth;  the  larvae  hatch 
in  a  day  or  two  and  feed  on  the  refuse  ;  they  may  be  full-grown 
in  five  or  six  days,  and,  then  pupating,  may  in  another  wreek  emerge 
as  perfect  flies.  Hence  it  is  no  wonder  that  they  increase  to 
enormous  numbers  in  favourable  climates.  They  are  thought  to 
pass  the  winter  chiefly  in  the  pupal  state.  The  House-fly  is 
now  very  widely  distributed  over  the  world  ;  it  sometimes  occurs 
in  large  numbers  away  from  the  dwellings  of  man.  Of  Blow- 
flies there  are  two  common  species  in  this  country,  Callipliora 
erytlirocephala  and  C.  vomitoria.  The  Green-bottle  flies,  of  which 
there  are  several  species,  belonging  to  the  genus  Lucilia,  have  the 
same  habits  as  Blow-flies,  though  they  do  not  commonly  enter 
houses.  The  larvae  are  said  to  be  indistinguishable  from  those  of 
Calliphora. 

The  larvae  of  Eumyiid  Muscidae  are,  when  first  hatched, 
metapneustic,  but  subsequently  an  anterior  pair  of  stigmata 
appears,  so  that  the  larva  becomes  amphipneustic.  They 
usually  go  through  three  stages,  distinguished  by  the  condition 
of  the  posterior  stigmata.  In  the  early  instar  these  have  a 
single  heart-shaped  fissure,  in  the  second  stage  two  fissures  exist, 


5  1 2  DIPTERA  CHAP. 


while    in    the   third    instar  there   is  a  greater   diversity  in   the 
condition  of  the  breathing  apertures. 

The  various  forms  of  Muscidae  show  considerable  distinctions  • 
in  the  details  of  their  natural  history,  and  these  in  certain  species 
vary  according  to  the  locality.  This  subject  has  been  chiefly 
studied  by  Portschinsky,  a  Russian  naturalist,  and  a  very  interest- 
ing summary  of  his  results  has  been  given  by  Osten  Sacken,1 
to  which  the  student  interested  in  the  subject  will  do  well 
to  refer. 

A  few  years  ago  a  great  deal  of  damage  was  caused  in  the 
Netherlands  by  Lucilia  sericata,  a  Green-bottle-fly,  extremely 
similar  to  our  common  L.  caesar,  which  deposited  its  eggs  in 
great  quantities  on  sheep  amongst  their  wool.  This  epidemic 
wr.s  attributed  to  the  importation  of  sheep  from  England  ;  but, 
according  to  Karsch,  there  is  reason  to  suppose  that  the  fly  was 
really  introduced  from  Southern  Europe  or  Asia  Minor." 

The  larvae  of  species  of  the  genus  Lucilia  sometimes  attack 
man  and  animals  in  South  America,  but  fortunately  not  in  this 
country.  The  larva  of  Lucilia  (CompsomyicC)  macellaria  is  called 
the  screw-worm,  and  is  the  best  known  of  the  forms  that  infest 
man,  the  larvae  living  in  the  nasal  fossae  and  frontal  sinuses, 
and  causing  great  suffering.  The  fly  is  common  in  North 
America,  but  is  said  never  to  attack  man  farther  north  than 
in  Kansas.  A  little  fly  (Stomoxys  calcitrans),  very  like  the 
common  house-fly  though  rather  more  distinctly  spotted  with 
grey  and  black,  and  with  a  fine,  hard,  exserted  proboscis, 
frequently  enters  our  houses  and  inflicts  a  bite  or  prick  on  us. 
It  is  commonly  mistaken  for  an  ill-natured  house-fly  that  has 
taken  to  biting.  It  is  frequently  a  source  of  irritation  to  cattle. 
A  closely  allied  fly,  HaematoHa  serrata,  is  very  injurious  to  cattle 
in  North  America,  but  the  same  species  causes  no  serious  annoy- 
ance in  England.  We  may  mention  that  the  various  attacks  of 
Dipterous  larvae  on  man  have  received  the  general  name 
"  myiasis." 

The  Tse-tse  fly  (Glossina  morsitans),  another  ally  of  Stomoxys, 
is  not  very  dissimilar  in  size  and  shape  to  the  blow -fly.3 

1  Berlin,  ent.  Zeitsclir.  xxxi.  1887,  p.  17. 

-  Biol.  Centrum,  vii.  1887,  p.  521. 

3  For  an  account  of  the  habits  of  this  fly,  see  Kirk,  J.  Linn.  Soc.  viii.  1S65»  pp. 
149-156  ;  and  for  a  bibliographic  list,  Wulp,  Tijdschr.  Ent.  xxvii.  1884,  p.  xci.  and 
pp.  143-140. 


VII 


MUSCIDAE TSE-TSE    FLY 


513 


FIG.  244. — The  Tse-tse  fly  (Glossma  morsi- 

t«nx).    A,  The  fly  with  three  divisions 

of  the    proboscis    projecting  ;    B,   adult 
larva  ;  C,  pupa. 


It    bites    man    and    animals    in    South    Africa,    and    if    it    have 

previously  bitten  an  animal 
whose  blood  was  charged  with 
the  Haematozoa  that  really  con- 
stitute the  disease  called  Nagana 
(fly-disease),  it  inoculates  the 
healthy  animal  with  the  dis- 
ease ;  fortunately  only  some 
species  are  susceptible,  and  man 
is  not  amongst  them.  It  has 
recently  been  shown  by  Surgeon 
Bruce  l  that  this  fly  multiplies 
by  producing,  one  at  a  time,  a 
full-grown  larva,  which  imme- 
diately changes  to  a  pupa,  as 
do  the  members  of  the  series 
Pupipara.  There  are  already 
known  other  Muscid  flies  with  peculiarities  in  their  modes  of 
reproduction,  so  that  it  is  far  from  impossible  that  the  various  con- 
ditions between  ordinary  egg-laying  and  full-grown  larva-  or  pupa- 
production  may  be  found  to  exist.  Although  it  has  been  supposed 
that  the  Tse-tse  fly  is  a  formidable  obstacle  to  the  occupation  of 
Africa  by  civilised  men,  there  is  reason  to  suppose  that  this  will 
not  ultimately  prove  to  be  the  case.  It  only  produces  disease  when 
this  pre-exists  in  animals  in  the  neighbourhood ;  only  certain 
species  are  liable  to  it ;  and  there  is  some  evidence  to  the  effect 
that  even  these  may  in  the  course  of  a  succession  of  generations 
become  capable  of  resisting  the  disease  inoculated  by  the  fly.  As 
long  ago  as  1878  Dr.  Drysdale  suggested2  that  this  fly  only  pro- 
duces disease  by  inoculating  a  blood-parasite,  and  all  the  evidence 
that  has  since  been  received  tends  to  show  that  his  idea  is  correct. 
Although  the  facts  we  have  mentioned  above  would  lead  to 
the  supposition  that  Muscidae  are  unmitigated  nuisances,  yet  it 
is  probable  that  such  an  idea  is  the  reverse  of  the  truth,  and 
that  on  the  whole  their  operations  are  beneficial.  It  would  be 
difficult  to  overestimate  their  value  as  scavengers.  And  in 
addition  to  this  they  destroy  injurious  creatures.  Thus  in 
Algeria  Id  la  fosciata,  a  fly  like  the  House  -  fly,  destroys  the 


1  Preliminary  Report  on  the  Tse-tse  Fly  Disease,  1895. 
2  P.  Liverpool  Soc.  xxxiii.  1878,  p.  13,  note. 


VOL.  VI 


2   L 


5  1 4  DIPTERA  CHAP. 

dreaded  migratory  Locust  Sch  istocerca  peregrina  in  great  quantities, 
by  the  larvae  eating  the  eggs  of  the  Locust.      The  female  of  this 
fly,  in  order   to   reach   the   desired  food,  penetrates   from  one   to. 
three  inches  below  the  surface  of  the  ground. 

Fam.  39.  Oestridae  (Bot-flies). — Rather  large  or  very  large 
flies,  with  extremely  short  antennae,  hearing  a  segmented  arista,  the 
front  of  the  head  prominent,  the  posterior  part  of  the  wings  fre- 
quently rough,  and  with  but  few  veins  :  the  mouth  usually  atrophied,' 
the  trophi  being  represented  only  l>y  tubercles  ;  larvae  living  in  Vcrte- 
brates,  usually  Mammals,  though  it  is  possible  that  a  few  occur  in 
Birds  and  even  in  Reptiles.  This  is  a  family  of  small  extent,  less 
than  100  species  being  known  from  all  the  world,  yet  it  is  of 
much  interest  on  account  of  the  habits  of  its  members,  which, 
though  of  large  size,  live  entirely  at  the  expense  of  living  Verte- 
brates, to  the  viscera  or  other  structures  of  which  they  have  definite 
relations,  varying  according  to  the  species.  Some  (Gastrophilus,etc.) 
live  in  the  alimentary  canal;  others  (Hypoderma,  etc.)  are  encysted 
in  or  under  the  skin;  while  others  (Oestrus,  etc.)  occupy  the  respir- 
atory passages.  As  many  of  them  attack  the  animals  used  by  man, 
and  some  of  them  do  not  spare  man  himself,  they  have  attracted 
much  attention,  and  there  is  an  extensive  literature  connected 
with  them  ;  nevertheless  the  life-histories  are  still  very  incom- 
pletely known.  Indeed,  the  group  is  from  all  points  of  view  a 
most  difficult  one,  it  being  almost  impossible  to  define  the  family 
owing  to  the  great  differences  that  exist  in  important  points. 
.Some  think  the  family  will  ultimately  be  dismembered ;  and 
Girschner  has  recently  proposed  to  treat  it  as  a  division  of 
Tachinidae.  The  chief  authority  is  Brauer,  in  whose  writings 
the  student  will  find  nearly  all  that  is  known  about  Oestrida.e.1 
Some  of  them  exist  in  considerable  numbers  (it  is  believed  that 
they  are  now  not  so  common  as  formerly),  and  yet  the  flies  are 
but  rarely  met  with,  their  habits  being  in  many  respects  peculiar. 
Some  of  them,  for  purposes  of  repose,  frequent  the  summits  of 
mountains,  or  towers,  or  lofty  trees.  Some  have  great  powers  of 
humming;  none  of  them  are  known  to  bite  their  victims,  indeed 
the  atrophied  mouth  of  most  of  the  Oestridae  forbids  such  a  pro- 
ceeding. Some  deposit  their  eg(;'s  on  the  hairs  of  the  beasts  from 

1  We  may  specially  mention  the  monograph  of  Oestridae,  published  in  1863  by 
the  K.  k.  Zuol.  -  Jltit.  Gas.  JJ'icn,  and  supplements  in  IficH.  cut.  Zcit.  v.  vi.  1886, 
1887  ;  these  include  copious  bibliographic  lists. 


VII 


OESTRIDAE BOT-FLIES 


515 


which  the  larvae  are  to  draw  their  nutriment,  but  others  place 
their  larvae,  already  hatched,  in  the  entrances  of  the  nasal 
passages.  They  do  not  feed  on  the  blood  or  tissues  of  their 
victims,  but  on  the  secretions,  and  these  are  generally  altered  or 
increased  by  the  irritation  induced  by  the  presence  of  the  un- 
welcome guests.  It  would  appear,  on  the  whole,  that  their  presence 
is  less  injurious  than  would  be  expected,  and  as  they  always  quit 
the  bodies  of  their  hosts  for  the  purposes  of  pupation,  a  natural 
end  is  put  to  their  attacks.  We  have  ten  species  in  Britain,  the 
animals  attacked  being  the  ox,  the  horse,  the  ass,  the  sheep,  and 
the  red  deer  ;  others  occasionally  occur  in  connexion  with  animals 


FIG.  245. — Cephalomyia  maculata,  a  Bot-fly  of  the  camel.     Arabia.     A,  The  fly  with 
extended  wiugs  ;  B,  under  aspect  of  the  head  :  a,  antenna  ;  b,  the  obsolete  mouth-parts. 

in  menageries.  The  eggs  of  Gastrophilus  equi  are  placed  by  the 
fly,  when  on  the  wing,  on  the  hair  of  horses  near  the  front  parts 
of  the  body,  frequently  near  the  knee,  and,  after  hatching,  the 
young  larvae  pass  into  the  stomach  of  the  horse  either  by  being 
licked  off,  or  by  their  own  locomotion ;  in  the  stomach  they  be- 
come hooked  to  the  walls,  and  after  being  full  grown  pass  out 
with  the  excreta  :  the  Bots — as  these  larvae  are  called — are  some- 
times very  numerous  in  the  stomach,  for  a  fly  will  lay  as  many 
as  four  or  rive  hundred  eggs  on  a  single  horse  :  in  the  case  of 
\vcakly  animals,  perforation  of  the  stomach  has  been  known  to 
occur  in  consequence  of  the  habit  of  the  Bot  of  burying  itself  to 
a  greater  or  less  extent  in  the  \valls  of  the  stomach.  Hypodermct 
Iiorifs  and  If.  lineata  attack  the  ox,  and  the  larvae  cause  tumours 
in  the  skin  along  the  middle  part  of  the  back.  It  was  formerly 


5l6  DIPTERA  CHAP. 

inferred  from  this  that  the  fly  places  its  eggs  in  this  situation, 
and  as  the  cattle  are  known  to  dread  and  flee  from  the  fly,  it 
was  supposed  to  be  on  account  of  the  pain  inflicted  when  the  egg  • 
was  thrust  through  the  skin.  Recent  observations  have  shown 
that  these  vi#ws  are  erroneous,  but  much  still  remains  to  be  ascer- 
tained. The  details  of  oviposition  are  not  yet  fully  known, 
but  it  appears  that  the  eggs  are  laid  on  the  lower  parts  of  the 
body,  especially  near  the  heels,  and  that  they  hatch  very  speedily.1 
As  the  imago  of  Hypoderma  appears  for  only  a  very  short  period  in 
the  summer,  the  time  of  the  oviposition  is  certain.  The  newly- 
disclosed  larva  is  considerably  different  from  the  more  advanced 
instar  found  in  the  skin  of  the  back  ;  moreover,  a  long  period  of 
many  months  intervenes  between  the  hatching  of  the  larva  and 
its  appearance  in  the  part  mentioned.  Brauer  has  shown  that 
when  the  grub  is  first  found  in  that  situation  it  is  entirely  sub- 
cutaneous. Hence  it  would  be  inferred  that  the  newly-hatched 
larva  penetrated  the  skin  probably  near  the  spot  it  was  deposited 
on,  and  passed  a  period  in  subcutaneous  wandering,  on  the  whole 
going  upwards  till  it  arrived  at  the  uppermost  part :  that  after 
moulting,  and  in  consequence  of  greater  need  for  air,  it  then 
pierced  the  skin,  and  brought  its  breathing  organs  into  contact 
with  the  external  air  ;  that  the  irritation  caused  by  the  admission 
of  air  induced  a  purulent  secretion,  and  caused  the  larva  to  lie 
enclosed  in  a  capsule.  Dr.  Cooper  Curtice  has  however  found, 
in  the  oesophagus  of  cattle,  larvae  that  he  considers  to  be  quite 
the  same  as  those  known  to  be  the  young  of  Hypoderma ;  and 
if  this  prove  to  be  correct,  his  inference  that  the  young  larvae 
are  licked  up  by  the  cattle  and  taken  into  the  mouth  becomes 
probable.  The  larva,  according  to  this  view,  subsequently  pierces 
the  oesophagus  and  becomes  subcutaneous  by  passing  through  the 
intervening  tissues.  The  later  history  of  the  grub  is  briefly,  that 
when  full  grown  it  somewhat  enlarges  the  external  orifice  of  its 
cyst,  and  by  contractions  and  expansions  of  the  body,  passes  to 
the  surface,  falls  to  the  ground,  buries  itself  and  becomes  a  pupa. 
If  Dr.  Curtice  be  correct,  there  should,  of  course,  be  as  mam. 
if  not  more,  larvae  found  in  the  oesophagus  as  in  the  back 
of  the  animal;  but,  so  far  as  is  known,  this  is  not  the  case,  ami 
we  shall  not  be  surprised  if  the  normal  course  of  development  be 
found  different  from  what  Dr.  Curtice  supposes  it  to  be.  His 

1    Kilcy,  Insect  Life,  iv.  1892,  p.  302. 


vii  OESTRIDAE PUPIPARA  517 


observations  relate  to  Hypoderma  lineata.  Our  common  British 
species  is  usually  supposed  to  be  H.  bovis ;  but  from  recent  ob- 
servations it  seems  probable  that  most  of  the  "  Ox-warbles  "  of  this 
country  are  really  due  to  the  larvae  of  H.  lineata. 

The  history  of  Oestrus  ovis,  which  attacks  the  sheep,  is  also 
incompletely  known,  but  appears  to  be  much  simpler.  This  fly 
is  viviparous,  and  deposits  its  young  larvae  at  the  entrance  of  the 
nasal  passages  of  the  sheep,  thereby  causing  extreme  annoyance 
to  the  animal.  The  larvae  penetrate  to  the  frontal  sinuses  to 
complete  their  growth.  The  duration  of  their  lives  is  unknown, 
for  it  is  commonly  the  case  that  larvae  of  various  sizes  are  found 
together.  Ceplienomyia  rufibarbis  has  recently  been  found  in 
Scotland.  It  attacks  the  Ked  deer,  and  its  life-history  is  similar 
to  that  of  Oestrus  ovis,  though  the  larvae  apparently  prefer  to 
attain  their  full  growth  in  the  pharynx  of  the  deer. 

In  reference  to  the  Oestridae  that  attack  man,  \ve  may  merely 
mention  that  the  larva  of  the  Hypoderma  of  the  ox  is  occasionally 
found  in  Europe  infesting  human  beings,  but  only  as  an  extremely 
rare  and  exceptional  event ;  and  that  only  those  engaged  in 
attending  on  cattle  are  attacked  ;  from  which  it  is  inferred  that 
the  flies  are  deceived  by  an  odour  emanating  from  the  garments. 
In  America  numerous  cases  are  known  of  Oestrid  larvae  being 
taken  from  the  body  of  man,  but  information  about  them  is  very 
scanty.  It  appears,  however,  that  there  are  at  least  four  species, 
one  of  which,  Dermatobia  noxialis,  is  known  as  a  fly  as  well  as  a 
larva.  Whether  any  of  these  are  peculiar  to  man  is  uncertain.1 
There  are  several  larvae  of  Muscidae  that  have  similar  habits  to  the 
Oestridae  ;  hence  the  statements  that  exist  as  to  larvae  being  found 
in  birds  and  reptiles  cannot  be  considered  to  apply  to  members  of 
the  latter  family  until  the  larvae  have  been  studied  by  an  expert. 

The  family  Ctenostylidae  has  been  established  by  Bigot  for  a 
South  American  Insect,  of  which  only  a  single  individual  exists 
in  collections.  It  is  doubtful  whether  it  can  be  referred  to 
Oestridar.'-' 

Series  V.  Pupipara 

The  four  families  included  in  this  Series  are,  with  the 
exception  of  the  Hippoboscidae,  very  little  known.  Most  of 

1  See  Blanchard,  Ann.  ,S'oc.  ent.  France  (7)  ii.  1892,  pp.  109,  154. 

2  See  Bigot,  Ann.  Soc.  ent.  France  (6)  ii.  1882,  p.  21,  Brauer.  Monoyraph.  1863, 
p.  51,  and  Wicn.  ent.  Zeit.  vi.  1887,  p.  75. 


5  I  8  DIPTERA 


CHAP. 


them  live  by  sucking  blood  from  Mammals  and  Birds,  and  some- 
times they  are  wingless  parasites.  The  single  member  of  the 
family  Braulidae  lives  011  bees.  The  term  Pupipara  is  erroneous, 
and  it  would  be  better  to  revert  to  Reaumur's  prior  appellation 
Xymphipara.  Miiggenburg  has  suggested  that  the  division  is 
not  a  natural  one,  the  points  of  resemblance  that  exist  between 
its  members  being  probably  the  results  of  convergence.  Eecent 
discoveries  as  to  the  modes  of  bringing  forth  of  Muscidae  give 
additional  force  to  this  suggestion.  A  satisfactory  definition  of 
the  group  in  its  present  extent  seems  impossible. 

Fam.  40.  Hippoboscidae. —  Wings  very  variable,  sometimes 
present  and  lanje,  then  with  waved  surface  and  tJiicJc  nervures 
confined  to  the  anterior  and  ha  sal  part  ;  sometimes  mere  strips, 
sometimes  entirely  absent.  Certain  members  of  this  family  are  well 
known,  the  Forest-fly,  or  Horse-fly,  and  the  Sheep-tick  belonging  to 
it.  The  proboscis  is  of  peculiar  formation,  and  not  like  that  of  other 
flies.  Seen  externally  it  consists  of  two  elongate,  closely  adapted, 
hard  flaps  ;  these  are  capable  of  diverging  laterally  to  allow  an  inner 
tube  to  be  exserted  from  the  head.  The  details  and  morphology 
of  the  structure  have  recently  been  discussed  by  Miiggenburg.1 
Melophaijus  ovinus,  commonly  called  the  Sheep-tick,  is  formed  for 
creeping  about  on  the  skin  of  the  sheep  beneath  the  wool,  and 
may  consequently  be  procured  with  ease  at  the  period  of  sheep- 
shearing  :  it  has  no  resemblance  to  a  fly,  and  it  is  difficult  to 
persuade  the  uninitiated  that  it  is  such.  Hippobosca  equina  (called 
in  this  country  the  Forest-fly,  perhaps  because  it  is  better  known 
in  the  New  Forest  than  elsewhere),  looks  like  a  fly,  but  will  be 
readily  recognised  by  the  two  little  cavities  on  the  head,  one 
close  to  each  eye,  in  which  the  antennae  are  concealed,  only  the 
fine  bristle  projecting.  Very  little  seems  to  be  known  as  to 
the  Natural  History  of  this  fly.  Lipoptena  cervi  lives  on  the 
Red  deer;  the  perfect  Insect  has  apparently  a  long  life,  and  both 
sexes  may  be  found  in  a  wingless  state  on  the  deer  all  through 
the  winter.  When  first  disclosed  in  the  summer  they  are  how- 
ever provided  with  wings,  but  when  they  have  found  a  suitable 
host  they  bite  off,  or  cast,  the  wings.  The  female,  it  appears,  does 
this  more  promptly  than  the  male,  so  that  it  is  difficult  to  get 
winged  individuals  of  the  former  sex.2  Most  of  the  known 

1  Arch.  Naturgesch.  Iviii.  1.1S92,  pp.  287-322,  pis.  xv.  xvi. 
-  Stein,  Deutsche  ent.  Zc.it.  xxi.  1877,  p.  297. 


VII 


HIPPOBOSCIDAE 


519 


to-   x  a, 
\^J> 


Hippoboscidae  live  on  birds,  and  are  apparently  specially  fond  of 
the  Swallow  tribe.  They  are  all  winged,  though  in  some  species 
the  wings  are  very  small.  The  bird- 
infesting  Hippoboscidae  have  been  very 
little  studied,  and  will  probably  form  a 
distinct  family ;  the  antennae  of  Sten- 
opteryx  kirundinis  are  quite  different 
from  those  of  Hippolosca.  The  devel- 
opment is  remarkable,  and  has  been 
studied  by  Leuckart l  and  by  Pratt 2  in 
the  case  of  Melophagus  ovinus.  Tbe 
ovaries  are  peculiarly  formed,  and  pro- 
duce one  large  egg  at  a  time ;  this 
passes  into  the  dilated  oviduct,  and  there 
goes  through  its  full  growth  and  a  cer- 


P 


Till 


,  . ,    .      J ,  FIG.  246. — Diagrammatic  section 

tain  amount  ot  development ;  it  is  then        Of  the  larva  of  Meiophagus 
extruded,  and  undergoing  little   or    no        m'inus-     (After  Pratt-)     «• 

mouth  ;    b,  suctorial  pouch  ; 

change     of     form     becomes    externally        c,  imaginai  disc   for   adult 

head  ;  d,  meso-  and  meta- 
notal  discs,  e,  anterior  trach- 
eal anastomosis  ;  f,  first 
muscular  belt  ;  g,  transverse 
tracheal  branch  ;  h,  the  dorsal 
tracheal  tube  ;  i,  sex-orgau  ; 
A-,  Malpighian  tube  ;  I,  ter- 
minal part  of  intestine  ;  m, 
terminal  chamber  of  tracheal 
tube  ;  n,  stigmatic  fossa  ;  o, 
terminal  part  of  intestine  ;  p, 
anus  ;  q,  anal  disc  ;  r,  ventral 
tracheal  tube  ;  s,  stomach  ; 
t,  nervous  system  ;  u,  discs 
for  the  three  pairs  of  legs  of 
the  imago  ;  v,  ventral  pouch  ; 
W,  pharynx  ;  x,  suctorial  lip. 


hardened  by  the  excretion  of  chitin, 
passing  thus  into  the  condition  of  the 
Eumyiid  pupa.  Dufour  thought  that 
there  is  no  larval  stage  in  this  Insect, 
but  it  is  quite  clear  from  later  researches 
that  he  was  wrong,  and  that  a  larval 
stage  of  a  peculiar  kind,  but  in  some  re- 
spects resembling  that  of  the  Eumyiid 
Muscidae,  occurs.  The  larva  has  no 
true  head,  but  the  anterior  part  of  the 
body  is  invaginated,  and  the  most 
anterior  part  again  protrudes  in  the 

invagination,  so  that  two  little  passages  appear  on  section  (Fig. 
246) ;  the  upper  one  leads  to  the  stomach,  which  is  of  very 
large  size.  The  tracheal  system  is  peculiar ;  it  is  metapneustic, 
there  being  neither  anterior  nor  lateral  spiracles.  Pratt  says 
that  there  is  at  first  a  single  pair  of  terminal  spiracles,  and  sub- 
sequently three  pairs,  hence  he  considers  that  the  terminal  part 
of  the  body  corresponds  to  three  segments.  This  is  however 
probably  a  mistaken  view ;  it  appears  more  probable  that  the  so- 
called  three  pairs  of  stigmata  really  correspond  with  the  complex 

1  Abh.  Ges.  Halle,  iv.  1858,  p.  145.         -  Arch.  Natunjcsch.  lix.  i.  1893,  p.  151. 


52O 


DIPTERA 


CHAP. 


condition  of  the  stigmata  in  the  later  instars  of  certain  other 
Dipterous  larvae.  The  Melophagus-l&rva.  is  nourished  by  secre- 
tion from  certain  glands  of  the  mother-fly ;  this  is  swallowed  ' 
and  the  stomach  is  greatly  distended  by  this  milky  fluid. 
Probably  it  was  this  condition  that  induced  Dufour  to  suppose 
the  larva  to  be  only  an  embryo. 

Some  of  the  Hippoboscidae  that  live  on  birds  take  to  the 
wing  with  great  readiness,  and  it  is  probable  that  these  bird- 
parasites  will  prove  more  numerous  than  is  at  present  suspected. 
We  may  here  notice  an  animal  recently  described  by  Dr. 
Adensamer  and  called  Ascodipteron.1  He  treats  it  as  the  female 
imago  of  a  Pupiparous  Dipteron.  It  was  found  buried  in  the 
skin  of  the  wing  of  a  bat  of  the  genus  Phyllorhina,  in  the 
Dutch  East  Indies,  only  one  individual  being  known.  It  is 
entirely  unsegmented,  and  externally  without  head.  If  Dr. 
Adensamer  should  prove  to  be  correct  in  his  surmise  the  creature 
can  scarcely  be  inferior  in  interest  to  the  Strepsiptera. 

Fam.  41.   Braulidae. — This  consists  only  of  a  minute  Insect 
that  lives  on  bees.      The  antennae  are   somewhat   like   those  of 

the  sheep-tick,  though 
they  are  not  so  com- 
pletely concealed  in 
the  cavities  in  which 
they  are  inserted.  Ac- 
cording to  Muggen- 
burg '"'  a  ptilinum 
exists,  and  he  is  also 
of  opinion  that  al- 
though the  parts  of 
the  mouth  differ  very 
much  from  those  of 
Hippoboscidae  they 


FIG.  247. — Braula  coeca. 


x-1/. 


(After  Meinert.) 


are  essentially  similar.  Lucas  says  that  Braula  specially  affects 
the  thorax  of  the  bee :  Miiggenburg,  that  it  is  fond  of  the 
queen-bee  because  of  the  exposed  membranes  between  the  body- 
segments  that  exist  in  that  sex.  Whether  this  Insect  is  truly 
Pupiparous  is  unknown,  though  Boise  states  that  a  pupa  is 
deposited  in  the  cell  of  the  bee  by  the  side  of  the  young  larva  of 

1  SB.  AI-.   Jl'icn.  cv.  1896,  Abthcil.  i.  p.  400. 
-  Arch.  Xutioy*.  Iviii.  i.  1892,  \>.  287. 


VII 


BRAULIDAE STREBLIDAE NYCTERIBIIDAE 


521 


the  bee,  and  appears  as  the  perfect  Insect  in  about  twenty-one 
i  lays.  Miiggenburg  suggests  that  Braula  may  be  oviparous,  as  he 
has  never  found  a  larva  in  the  abdomen.  Packard  says  that  on  the 
<lay  the  larva  hatches  from  the  egg  it  sheds  its  skin  and  turns  to  an 
oval  puparium  of  a  dark  brown  colour.  The  Insect  is  frequently 
though  inappropriately  called  bee-louse  ;  notwithstanding  its  name 
it  is  not  quite  blind,  though  the  eyes  are  very  imperfect. 

Fam.  42.  Streblidae.  -  -  Winged ;  possessing  halteres ;  the 
I i  cad  small,  narrow  and  free.  These  very  rare  Diptera  are 
altogether  problematic.  According  to  Kolenati  the  larvae  live  in 
bats'  excrement  and  the  perfect  Insects  011  the  bats.1  If  the 
former  statement  be  correct  the  Insects  can  scarcely  prove  to  be 
Pupipara.  The  wing-nervuration  is,  in  the  figures  of  the 
Kussian  author,  quite  different  from  that  of  Hippoboscidae.  The 
Streblidae  have  been  associated  by  some  entomologists  with 
]STycteribiidae,  and  by  Williston  with  Hippoboscidae. 

Family  43.   Nycteribiidae. — The  species  of  this  family  are 

v         l/~^^^~~  /~ezz~^  ~~^^ 


FIG.  248.  • — Nycteribia  sp. ,  from  Xantharpyia  stra?ninea.     Aden.     A,  Upper  surface  of 
female,  with  head  in  the  position  of  repose  ;  B,  under  surface  of  male.       x  If-. 

found   on   bats;  they  are  apparently  rare,  and  we  have  been  able 

to   examine  only   one   species.      The    form  is  very  peculiar,   the 

'  Home  Soc.  ent.  Eoss.  ii.  1863,  p.  90. 


522 


DIPTERA APHANIPTERA 


CHAP. 


Insects  looking  as  if  the  upper  were  the  under  surface.  They 
are  wingless,  with  a  narrow  head,  which  reposes  on  the  hack  of  the 
thorax.  The  prothorax  appears  to  be  seated  on  the  dorsuin  of  the 
mesothorax.  According  to  Miiggenburg  there  is  no  trace  of  a 
ptilinum.  A  brief  note  on  the  metamorphosis  1  by  Baron  Osten 
Sacken  indicates  that  the  mature  larva  differs  from  that  of 


FIG.  249. — Anterior  part  of  the  body  of  Nycteribia  sp.,  found  on  Xantharpyia  straw inea 
by  Colonel  Yerbtiry  at  Aden.  A,  Upper  surface  of  female,  with  head  extended  ; 
B,  under  surface  of  male,  with  head  extended  ;  C,  claws  of  a  foot. 

Melophagus  in  the  arrangement  of  the  stigmata ;  they  appear  to 
be  dorsal  instead  of  terminal.  There  are  apparently  no  characters 
of  sufficient  importance  to  justify  the  association  of  these 
Insects  with  the  other  divisions  of  Pupipara  ;  the  sole  ground 
for  this  connection  being  the  supposed  nature  of  the  life-history 
of  the  larva. 


Sub-Order  Aphaniptera  or  Siphonaptera  (Fleas') 

Fam.  Pulicidae. —  Wingless,  with  the  body  laterally  compressed, 
so  that  the  transverse  diameter  is  small,  the  vertical  one  great.  The 
licinl  indistinctly  separated  from  tlie  l>t>dj/,  smal/,  iritJi  s/mrt  thick 
antennae  />/<tccd  in  depressions  so/in'/r//,/f,  behind  and  above  the  vn- 
facetedeyes.  Tliexc  are  always  minute,  and  sometimes  tra-itting.— 

1    Tr.  cut.  Sue.  London,  1881,  p.  360. 


VII 


APHANIPTERA FLEAS 


523 


We  all  know  that  the  Flea  is  so  flat,  or  compressed  sideways,  that  it 

does  not  mind  the  most  severe 

squeeze.        This    condition     is 

almost  peculiar  to  it  ;  a  great 

flattening  of  the  body  is  com- 

mon in  Insects  —  as  is  seen  in 

another   annoying   Insect,  the 

bed-hug  —  but  the  compression, 

in   the  flea,  is  in   the  reverse 

direction.     In  Other  respects  the     FlG-  ^--Hystrichopsylla  t«!pae,.     Britain. 

\  (  After  Eitsema.) 

external   anatomy  ol   the    flea 

shows  several  peculiarities,  the  morphological  import  of  which  has 
not  yet  been  elucidated.  The  head  is  of  very 
peculiar  shape,  small,  with  the  antennae  placed 
in  an  unusual  position  ;  the  clypeus  is  said  to 
be  entirely  absent,  the  front  legs  are  articulated 
in  such  a  manner  that  they  have  a  large  addi- 
tional basal  piece  —  called  by  some  anatomists 
the  ischium  —  and  in  consequence  appear  to  be 
placed  far  forwards,  looking  as  if  they  were 
attached  to  the  head  ;  the  meso-  and  meta- 
thorax  have  certain  flaps  that  have  been  con- 
sidered to  be  homologues  of  wings  ;  and  the 
maxillary  palpi  are  attached  to  the  head  in 
such  a  way  that  they  appear  to  play  the  part 
of  the  antennae  of  other  Insects  (Fig.  250), 
and  were  actually  considered  to  be  the  antennae 
by  Linnaeus,  as  well  as  others  ;  the  mouth  - 

FIG.      251.  —  Mouth-  ,,  ,  ,.™          ,,  , 

parts  of  a  flea,  Ver-  Pa*ts  themselves  are  differently  constructed 
mipsyiia  aiakurt  from  those  of  any  other  Insects.1  The  maxillae 
organ  ;  and  labium  are  considered  to  be  not  only  present, 
jjut  we}}  developed,  the  former  possessing  palpi 
moderately  well  developed,  while  the  labial 
maxillary  palp.  paips  are  very  large  and  of  highly  peculiar 

(Alter  \\agner.)  J  °      J 

form,    being    imperfectly    transversely    jointed 
and  acting  as  sheaths  ;  the  mandibles  are  present  in  the  form  »  >1 

1  The  best  general  description  of  the  external  anatomy  of  the  flea  is  to  be  found 
in  Taschenberg,  Die  Flohe,  1880.  The  morphology  is  better  elucidated,  though  still 
incompletely,  in  Wagner's  valuable  "  Aphauipterologische  Studien,"  Horae  Soc.  ent. 
Jioss.  xxiii.  1889,  pp.  199-260,  5  plates,  and  oj).  cit.  xxxi.  1897,  pp.  555-594,  3 
plates.  Cf.  also  X.  C.  Rothschild,  Nov.  Zool.  v.  1898,  pp.  533-544,  3  plates. 


pricking 

Lp.   labi.il   palp  ; 

Md.    mandible; 

MX.  maxilla  ;  M.v. 


524 


APHANIPTERA 


CHAP. 


a  pair  of  elongate,  slender  organs,  with  serrated  edges  ;  and  there 
is  an  unpaired,  elongate  pricking-organ,  thought  by  some  to  Le  a 
hypopharynx,  and  by  others  a  labrum.  The  antennae  are  of 
unusual  form,  consisting  of  two  basal  joints,  and,  loosely  con- 
nected therewith,  a  terminal  mass  of  diverse  form  and  more  or 
less  distinctly,  though  irregularly,  segmented.  The  full  number 
of  ten  stigmata  exists,  Wagner  giving  three  thoracic,  with  seven 
abdominal,  placed  on  segments  2-8  of  the  abdo- 
men ;  but  Packard  thinks  the  supposed  meta- 
thoracic  stigma  is  really  the  first  abdominal. 
Fleas  undergo  a  very  complete  metamorphosis  ; 
the  larvae  are  wormlike,  resembling  those  of 
Mycetophilid  Diptera  (Fig.  252).  The  egg  of 
the  cat's  flea  is  deposited  among  the  fur  of  the 
animal,  but  (unlike  the  eggs  of  other  parasites) 
apparently  is  not  fastened  to  the  hair,  for  the 
eggs  fall  freely  to  the  ground  from  infested 
animals  ;  the  young  larva  when  hatched  bears 
on  the  head  a  curious  structure  for  breaking 
the  egg-shell.  It  has  the  mouth  -parts  of  a 
mandibulate  Insect  and  is  peripiieustic,  having 
ten  pairs  of  stigmata.  It  subsequently  becomes 
of  less  elongate  form.  Flea-larvae  are  able  to 
nourish  themselves  on  almost  any  kind  of  refuse 
animal  matter,  Laboulbene  having  reared  them 
on  the  sweepings  of  apartments  ;  they  may 

Fie.   252.  —  Larva    of  .  „ 

vy/.s   perhaps  sometimes  teed  on    blood  ;  at   any  rate 


LJ 


the  dog-  and  cat-   the  contents  of  the  alimentary  canal  appear  red 

llea.  (After 

Kunckel.)  through    the    transparent   integuments.      VV  hen 

full  grown  the  larva  makes  a  cocoon,  and 
frequently  covers  it  with  pieces  of  dust.  The  perfect  flea 
appears  in  a  week  or  two  thereafter  ;  the  pupa  has  the  members 
free.  The  food  of  the  larvae  of  fleas  has  been  much  discussed 
and  a  variety  of  statements  made  on  the  subject.  It  has  been 
stated  that  the  mother-flea  after  being  gorged  with  blood  carries 
some  of  it  to  the  young,  but  Kunckel  has  shown  that  there  is 
very  little  foundation  for  this  tale.  Enormous  numbers  of  fleas 
are  sometimes  found  in  uninhabited  apartments  to  which  animals 
have  previously  had  access,  and  these  fleas  \vill  attack  in  numbers 
and  with  great  eagerness  any  unfortunate  person  who  may  enter 


vir  FLEAS  525 

the  apartment.  The  cat-flea  can  pass  through  its  growth  and 
metamorphosis  with  excessive  rapidity,  the  entire  development  of 
a  generation  in  favourable  conditions  extending  but  little  beyond 
a  fortnight.1 

About  a  hundred  kinds  of  fleas  are  known,  all  of  which  live 
on  mammals  or  birds.  Hystrichopsylla  talpae  (Fig.  250)  is  one 
of  the  largest,  it  occurs  on  the  Mole.  It  was  found  by  Eitsema 
in  the  nests  of  Bombus  subterraneus  (and  was  described  under 
the  name  of  Ptdcx  obtu&iceps).  As  these  nests  are  known  to  be 
harried  by  Voles,  and  as  this  flea  has  also  been  found  on  Field- 
mice,  it  is  probable  that  the  parasites  are  carried  to  the  nests 
by  the  Voles.  The  species  that  chiefly  infests  man  is  Pulex 
irritans,  an  Insect  that  is  nearly  cosmopolitan,  though  arid  desert 
regions  are  apparently  unsuitable  to  it.  Pulex  avium  occurs  on 
a  great  variety  of  birds.  P.  serraticeps  infests  the  dog  and  the 
cat,  as  well  as  a  variety  of  other  Mammals.  It  is  a  common 
opinion  that  each  species  of  Mammal  has  its  owrn  peculiar  flea, 
but  this  is  far  from  correct.  Fleas  pass  readily  from  one  species 
of  animal  to  another ;  the  writer  formerly  possessed  a  cat  that 
was  a  most  determined  and  successful  hunter  of  rabbits,  and  she 
frequently  returned  from  her  excursions  swarming  with  fleas  that 
she  had  become  infested  with  when  in  the  rabbits'  burrows  ;  lier 
ears  were  on  some  occasions  very  sore  from  the  flea-bites.  Some 
of  the  fleas  of  other  animals  undoubtedly  bite  man.  There 
appears,  however,  to  be  much  difference  in  the  liability  of  different 
individuals  of  our  own  species  to  the  bites  of  fleas.  Sarcopsylla 
penetrans  differs  in  habits  from  other  fleas,  as  the  female 
buries  the  anterior  parts  of  her  body  in  the  flesh  of  man  or 
other  Vertebrates,  and  the  abdomen  then  becomes  enormously 
enlarged  and  distended  and  undergoes  a  series  of  changes  that 
are  of  much  interest.2  While  in  this  position  the  Insect  dis- 
charges a  number  of  eggs.  This  species  multiplies  sufficiently 
to  become  a  serious  pest  in  certain  regions,  the  body  of  one  man 
having  been  known  to  be  affording  hospitality  to  300  of  these 
fleas.  Sarcopsylla  penetrans  is  known  as  the  Sand -flea,  or 
chigger,  and  by  numerous  other  names.  Originally  a  native  of 
tropical  America  it  has  been  carried  to  other  parts  of  the  world. 
Another  Sarcopsylla,  8.  gallinacea,  attaches  itself  to  the  eyelids 

1  Howard,  Bull.  Dcp.  Agric.  'Ent.  N.S.  No.  4,  1890. 
-  Schimkewitsch,  Zool.  Anz.  vii.  1884,  p.  673. 


526  APHANIPTERA THYSANOPTERA  CHAP. 

of  the  domestic  fowl  in  Ceylon,  and  an  allied  form,  Ehynchopsylla 
pulex,  fastens  itself  to  the  eyelids  and  other  parts  of  the  body  of 
birds  and  bats  in  South  America.  In  Turkestan  Vermipsylla 
alakurt  attacks  cattle — ox,  horse,  camel,  sheep — fastening  itself  to 
the  body  of  the  animal  after  the  fashion  of  a  tick.  Eetaining 
this  position  all  through  the  winter,  it  becomes  distended  some- 
what after  the  manner  of  the  Sand-flea,  though  it  never  forms 
a  spherical  body.  The  parts  of  the  mouth  in  this  Insect  (Fig.  251) 
are  unusually  long,  correlative  with  the  thickness  of  the  skins  of 
the  animals  on  which  it  lives.  Grassi  considers  that  the  dog's 
flea,  Pulex  serraticeps,  acts  as  the  intermediate  host  of  Taenia. 

Great  difference  of  opinion  has  for  long  prevailed  as  to 
whether  fleas  should  be  treated  as  a  Sub-Order  of  Diptera  or  as 
a  separate  Order  of  Insects.  Wagner  and  Kiinckel,  who  have 
recently  discussed  the  question,  think  they  may  pass  as  aberrant 
Diptera,  while  Packard,1  the  last  writer  on  the  subject,  prefers 
to  consider  them  a  separate  Order  more  closely  allied  to  Diptera 
than  to  any  other  Insects.  Although  widely  known  as  Aphan- 
iptera,  several  writers  call  them  Siphonaptera,  because  Latreille 
proposed  that  name  for  them  some  years  before  Kirby  called 
them  Aphaniptera.  Meinert  considers  them  a  separate  Order 
and  calls  it  Suctoria,  a  most  unfortunate  name. 

Order  VIII.   Thysanoptera. 

Small  Insects,  with  a  palpigerous  mouth  placed  on  the  under  side  of 

the  head  and  apposed  to  the  sternum  so   as  to   be  concealed. 

With  four  slender  wings,  fringed  with  hmy  hairs  on  one  or 

loth  m«  riji  us,  or  with  rudiments  of  wings,  or  entirely  apterous. 

Tarsi  of  one  or  two  joints,  terminated  by  a  vesicular  xlrncture. 

The  young  resemble  the  adult  in  general  form,  but  there  is  a 

pupal  stadium  in  which  the  Insect  is  quiescent  and   takes  no 

food. 

The  tiny  Insects  called  Thrips  are  extremely  abundant  and 
may  often  be  found  in  profusion  in  flowers.  Their  size  is  only 
tVi  11 11  -10  to  -J-  of  an  inch  in  length;  those  of  the  latter  magni- 
tude are  in  fact  giant  species,  and  so  far  as  we  know  at  present 
are  found  only  in  Australia  (Fig.  253).  As  regards  the  extent 

1  P.  Boston  Soc.  xxvi.  1894,  pp.  312-355. 


VII 


THRIPS 


of  the  Order  it  would  appear  that  Thysanoptera  are-  insignificant, 
as  less  than  150  species  are  known.  Thrips  have  been,  how- 
ever, very  much  neglected  by  entomologists,  so  it  will  not  be  a 
matter  for  surprise  if  there  should  prove  to  be  several  thousand 
species.  These  Insects 
present  several  points 
of  interest  ;  their 
mouth  -  organs  are 


unique  in  structure ; 
besides  this,  they  ex- 
hibit so  many  points 
of  dissimilarity  from 
other  Insects  that  it 
is  impossible  to  treat 
them  as  subdivisions 
of  any  other  Order. 
They  have,  however, 
been  considered  by 
some  to  be  aberrant 
I  'seudoneuroptera  (cf. 
Vol.  V.),  while  others 
have  associated  them 
with  Hemiptera.  Both 
Brauer  and  Packard 
have  treated  Thysa- 
noptera as  a  separate 
Order,  and  there  can 
be  no  doubt  that  this 
is  correct.  Thysano- 
ptera have  recently  been  monographed  by  Uzel  in  a  work  that  is, 
unfortunately  for  most  of  us,  in  the  Bohemian  language.1 

The  antennae  are  never  very  long,  and  are  6  to  9 -jointed. 
The  head  varies  much,  being  sometimes  elongate  and  tubular, 
but  sometimes  short ;  it  has,  however,  always  the  peculiarity  tb.it 
the  antennae  are  placed  quite  on  its  front  part,  and  that  the 
mouth  appears  to  be  absent,  owing  to  its  parts  being  thrust 
against  the  under  side  of  the  thorax  and  concealed.  Their  most 
remarkable  peculiarity  is  that  some  of  them  are  asymmetrical : 
Uzel  looks  on  the  peculiar  structure,  the  "  Mundstachel,"  m,  m 

1  Monographic  der  Ordnung  Thysanoptera,  Kbuiggratz,  -ito,  1895. 


FIG.  253. — Idolothrips  spectrum.     Australia. 


528 


THYSANOPTERA 


CHAP. 


(Fig.  254)  found  on  the  left  side  of  the  body,  as  probably  an  enor- 
mous development  of  the  epiphaiynx.     Previous  to  the  appearance 

of  Uzel's  work,  Garman  had,  however, 
correctly  described  the  structure  of  the 
mouth;1  he  puts  a  different  interpretation 
on  the  parts ;  he  points  out  that  the 
mandibles  (/),  so-called  by  Uzel,  are  at- 
tached to  the  maxillae,  and  he  considers 
that  they  are  really  jointed,  and  that 
they  are  lobes  thereof;  while  the  Mund- 
stachel  or  piercer  is,  he  considers,  the 
left  mandible  ;  the  corresponding  struc- 
ture of  the  other  side  being  nearly 
entirely  absent.  He  points  out  that 
the  labrum  and  endocranium  are  also 
asymmetrical.  We  think  Garman's 
view  a  reasonable  one,  and  may  re- 
mark that  dissimilarity  of  the  man- 
dibles of  the  two  sides  is  usual  in 
FIG.  254. — Face  (with  base  of  T  .,  ,.,  , 

the  antennae)  of  Aeolothrips  Insects,  and   that    the    mandibles    may 

fasciata.      (After    Uzel.)      a,    \)e  hollow  for    SUckillg,  as    is    shown    by 
Labrum  ;  b,  maxilla  with  its  .  -,••-, 

palp  (c) ;  bi,  terminal  part  of  the    larvae    ot     Hemerobiides.       There 

vertex    near     attachment    of   are    usually    three    ocelli,    hut    they    are 
mouth-parts  ;    it,    membrane 

between  maxilla  and  mentum ;  absent  in  the  entirely  apterous  forms. 

e,  mentum  ending  in  a  point  The    wi  appear    to     Spring     from 

near    / ;     y,     membrane     ot 

attachment  of  the  labial  palp  the    dorsal    surface    of    the    body,   not 

^e^ndlbiLfvi^S:;  from    the   sides;     the  anterior  pair   is 

base  of  mandible ;  I,  chitin-  always   quite   separated  from    the  pos- 
ous   lever ;    in,    mouth-spine,  ,  i  i  11 

with  its  thick  basal   part  n,  ten°r  5     tlle    wmgs    are    alwa7S    slender, 

and  o,  its  connection  with  sometimes    very    slender ;   in   other  re- 

•f Vjp      f*OT*f llHld        T       V*    "      it        i*OT* 

amen  of  muscle ;  a  and  t,   spects  they  exhibit  considerable  variety  ; 
points  of  infolding  of  vertex  -,   sometimes  the  front  pair  are  different 

u,    a     prolongation     of     the    .  .  „ 

geua.  in    colour    and    consistence    iroiu    the 

other  pair.  The  abdomen  has  ten  seg- 
ments, the  last  of  which  is  often  tubular  in  form.  The  peculiar 
vesicular  structures  by  which  the  feet  are  terminated  are,  during 
movement,  alternately  distended  and  emptied,  and  have  two  hooks 
or  claws  on  the  sides.  The  stigmata  are  extremely  peculiar, 
there  being  four  pairs,  the  first  being  the  mesothoracic,  2nd 

1  Bull.  Essex  lust.  xxii.  1890,  p.  24  ;  also  Amer.  Natural,  xxx.  1896,  p.  T>91. 


vii  THRIPS  529 

metathoracic,  3rd  on  the  second  abdominal  segment,  4th  on  the 
eighth  abdominal  segment.1  There  are  four  Malpighian  tubes, 
and  two  or  three  pairs  of  salivary  glands.  The  dorsal  vessel 
is  said  to  be  a  short  sack  placed  in  the  7th  and  8th  abdominal 
segments.  The  abdominal  ganglia  of  the  ventral  chain  are  con- 
centrated in  a  single  mass,  placed  in,  or  close  to,  the  thorax  ;  the 
thorax  has  two  other  approximated  ganglia,  as  well  as  an  anterior 
one  that  appears  to  be  the  infra-oesophageal. 

The  metamorphosis  is  also  peculiar  ;  the  larva  does  not  differ 
greatly  in  appearance  from  the  adult,  and  has  similar  mouth- 
organs  and  food-habits.  The  wings  are  developed  outside  the 
body  at  the  sides,  and  appear  first,  according  to  Heeger,  after 
the  third  moult.  The  nymph-condition  is  like  that  of  a  pupa 
inasmuch  as  no  nourishment  is  taken,  and  the  parts  of  the  body 
are  enclosed  in  a  skin  :  in  some  species  there  is  power  of  movement 
to  a  slight  degree,  but  other  species  are  quite  motionless.  In 
some  cases  the  body  is  entirely  bright  red,  though  subsequently 
there  is  no  trace  of  this  colour.  Jordan  distinguishes  two 
nymphal  periods,  the  first  of  which  he  calls  the  pronymphal ;  in 
it  the  Insect  appears  to  be  in  a  condition  intermediate  between 
that  of  the  larva  and  that  of  the  true  nymph  ;  the  old  cuticle 
being  retained,,  though  the  hypodermis  is  detached  from  it 
and  forms  a  fresh  cuticle  beneath  it.  This  condition,  as  Jordan 
remarks,  seems  parallel  to  that  of  the  male  Coccid,  and  ap- 
proaches closely  to  complete  metamorphosis ;  indeed  the  only 
characters  by  which  the  two  can  be  distinguished  appear  to 
be  (1)  that  the  young  has  not  a  special  form;  (2)  that  the 
wings  are  developed  outside  the  body. 

Thrips  take  their  food,  it  is  believed,  in  the  same  manner 
as  Aphidae,  by  suction  ;  but  the  details  of  the  process  are  not  by 
any  means  certain,  and  examination  of  the  stomach  is  said  to  have 
resulted  in  finding  pollen  therein.  Walsh  thought  that  Thy- 
sanoptera  pierce  and  suck  Aphidae.  An  elaborate  inquiry 
by  Osborn  2  failed  to  elicit  satisfactory  confirmation  of  Walsh's 
idea,  though  Eiley  and  Pergande  support  it  to  some  extent ; 
Osborn  concludes  that  the  ordinary  food  is  not  drawn  directly 
from  sap,  but  consists  of  exudation  or  pollen,  the  tissues 

1  Jordan  in  an  interesting  paper,  Zeitschr.  iciss.  Zool.  xlvii.  18SS,  p.  573,  says 
that  in  the  division  "  Terebrantia  "  there  are  only  three  pairs  of  stigmata. 

2  Insect  Life,  i.  1888,  p.  138. 

VOL.  VI  2  M 


53O  THYSANOPTERA  CHAP. 

of  the  plant  being  pierced  only  when  a  supply  of  food  from 
the  usual  sources  falls  short.  Members  of  this  family  have 
been  reputed  as  being  very  injurious  to  cultivated  plants,  especially' 
to  cereals,  and  it  is  said  that  as  a  result  the  harvests  in  Europe 
have  been  seriously  diminished.  Several  species  may  take  part 
in  the  attacks.  These  appear  to  be  directed  chiefly  against 
the  inflorescence.  Lindeman  thought  that  Limotlirips  denticornis 
(  =  Tlirips  secalina),  and  AntJiothrips  aculeata  ( =  =  Pkloeothrips 
frumentarius),  were  the  most  destructive  species  in  an  attack  of 
Thrips  on  corn  that  he  investigated  in  Russia.  Uzel  suggests 
that  injuries  due  to  other  causes  are  sometimes  ascribed  to  Thrips.1 
In  hot -houses  these  Insects  are  well  known,  and  sometimes 
occasion  considerable  damage  to  foliage.  The  German  horti- 
culturalists  call  them  black -fly,  in  distinction  from  Aphidae  or 
green-fly.  Some  Thysanoptera  live  under  bark,  and  even  in 
fungi,  and  in  Australia  they  form  galls  on  the  leaves  of  trees. 
This  observation  is  due  to  Mr  Froggatt,  and  is  confirmed  by 
specimens  he  sent  to  the  writer.  Vesicular  bodies  in  the  leaves 
of  Acacia  saliyna  were  traversed  on  one  side  by  a  longitudinal 
slit,  and  on  a  section  being  made,  nothing  but  Thrips,  in  various 
stages  of  growth,  was  found  inside  them.  A  second  kind  of  gall, 
forming  masses  of  considerable  size  on  the  twigs  of  Callistemon, 
is  said  by  Mr  Froggatt  to  be  also  due  to  Thrips,  as  is  a  third 
kind  on  Bursa-i'ia  spinosa.  It  is  curious  that  Thrips'  galls  have 
not  been  observed  in  other  parts  of  the  world. 

Thysanoptera  are  devoured  by  small  bugs  of  the  genus 
Tripli  Icjtx,  as  wrell  as  by  beetles ;  a  small  Acarid  attacks  them  1  >y 
fixing  itself  to  the  body  of  the  Thrips.  Xematode  worms  and  their 
eggs  were  found  by  Uzel  in  the  body-cavity.  He  found  no  less 
than  200  Nematodes  in  one  Thrips,  and  noticed  that  they  had 
entirely  destroyed  the  ovaries.  Woodpeckers,  according  to  him, 
tear  off  the  bark  of  trees  and  eat  the  Thysanoptera  that  are 
concealed  thereunder,  though  one  would  have  surmised  that 
these  minute  Insects  are  too  small  to  be  game  for  such  birds. 
They  have,  it  appears,  no  special  protection,  except  that  one 
species  (a  larva  of  Phlocotkrips  sp.)  is  said  to  emit  a  protective 
fluid. 

Parthenogenesis  seems  to  be  frequent  amongst  Thysanoptera, 

1  See  Lindemann,  Bull.  Soc.  Moscuu,  Ixii.  1886,  No.  2,  p.  296,  and  Uzel,  Mou. 
1895,  pp.  397,  398. 


vii  THRIPS  531 

and  is  found  in  concurrence  with  diversity  as  to  winged  and  wing- 
less females  of  the  same  species,  so  as  to  have  given  rise  to  the  idea 
that  the  phenomena  in  this  respect  are  parallel  with  those  that 
are  more  widely  known  as  occurring  in  Aphidae.  Under  certain 
circumstances  few  or  no  males  are  produced  (one  of  the  cir- 
cumstances, according  to  Jordan,  being  season  of  the  year),  and 
the  females  continue  the  species  partheiiogenetically.  In  other 
cases,  though  males  are  produced  they  are  in  very  small  numbers. 
Some  species  of  Thysanoptera  are  never  winged  ;  in  others  the 
individuals  are  winged  or  wingless  according  to  sex.  But  there 
are  other  cases  in  which  the  female  is  usually  wingless,  and 
is  exceptionally  winged.  The  winged  specimens  in  this  case 
are,  it  is  thought,  of  special  use  in  disseminating  the  species. 
Jordan  has  suggested  that  these  phenomena  may  be  of  a 
regular  nature,  but  Uzel  does  not  take  this  view.  Another 

O 

condition  may  lie  mentioned,  in  which  the  species  is  usually  wing- 
less, but  winged  individuals  of  the  male  as  well  as  of  the  female 
sex  occasionally  appear.  Thrips  lini  apparently  makes  regular 
migrations,  feeding  at  one  time  underground  on  the  roots 
of  flax,  and  then  changing  to  a  life  in  the  open  air  on  other 
plants. 

Numerous  forms  of  Thysanoptera,  belonging  to  both  of  the 
great  divisions  of  the  Order,  have  been  found  fossil  in  Europe 
and  North  America,  but  all  are  confined  to  deposits  of  the  Tertiary 
epoch. 

Of  the  135  species  known  to  Uzel,  117  are  European;  they 
are  divided  into  two  Sub-Orders.  1,  Terebrantia,  in  which  the 
females  are  provided  with  an  external  toothed  ovipositor,  of  two 
valves;  2,  Tubulifera,  in  which  there  is  no  ovipositor,  and  the 
extremity  of  the  body  is  tubular  in  both  sexes.  The  British 
species  are  about  50  in  number,  and  were  described  by 
Haliday  about  60  years  ago;1  of  late  they  have  been  very 
little  studied. 

The  name  Physopoda  or  Physapoda  is  used  for  this  Order, 
instead  of  Thysanoptera,  by  several  naturalists. 

1  Entomological  Magazine,  iii.  1836,  \\.  439,  and  iv.  1837,  \>.  144. 


CHAPTER   VIII 

HEMIPTERA OR    BUGS 

Order  IX.     Hemiptera. 

Mouth  consisting  of  a  proboscis  or  mobile  beak  (usually  conceal  «l 
/>//  being  bent  under  the  body\  appearing  as  a  tr  answer  sly - 
jointed  rod  or  grooved  sheath,  in  which  are  enclosed  long 
slender  setae  (like  horse-hairs).  Wings  (nearly  always) four  ; 
the  anterior  frequently  more  horny  than  the  posterior  pair, 
and  folding  flat,  on  the  back,  their  apical  portions  usually 
more  membranous  than  the  base  (Heteroptera) ;  or  the  four 
wings  may  cover  the  abdomen  in  a  roof -like  manner,  ami 
those  of  the  anterior  pair  may  not  have  tlie  basal  and  apical 
parts  of  different  consistences  (Homoptera) ;  sometimes  all 
four  of  the  wings  are  tra  HXJHI  rent.  Tlie  young  resembles  the 
adult  in  general  form ;  the  wings  are  developed  outside  tlie, 
body,  by  growth,  at  the  moults,  of  the  sides  of  the  hinder  por- 
tions of  the  meso-  and  meta-notum ;  tlie  metanotal  prolonga- 
tions being  more  or  less  concealed,  by  tlie  mesonotal. 

THE  Hemiptera  or  Bugs  are  perhaps  more  widely  known  as 
Khynchota.  In  deciding  whether  an  Insect  belongs  to  this 
Order  the  student  will  do  well  to  examine  in  the  first  place 
the  Leak,  treating  the  wings  as  suhordiuate  in  importance,  their 
condition  Leing  much  more  variaLle  than  that  of  the  Leak.  The 
ahove  definition  includes  no  reference  to  the  degraded  Anoplura 
or  Lice.  These  are  separately  dealt  with  on  p.  599  ;  they  are 
absolutely  wingless,  and  have  an  unjointed  proboscis  not  placed 
beneath  the  body,  the  greater  part  of  it  being  usually  withdrawn 
inside  the  body  of  the  Insect. 

The  Hemiptera   are   without   exception   sucking   Insects,  and 


CHAP.  VIII 


BUGS 


533 


the  mouth-organs  of  the  individual  are  of  one  form  throughout 
its  life.  In  this  latter  fact,  coupled  with  another,  that  the 
young  are  not  definitely  different  in  form  from  the  adult, 
Bugs  differ  widely  from  all  other  Insects  with  sucking-mouth. 
They  agree  with  the  Orthoptera  in  the  facts  that  the  mouth  does 
not  change  its  structure  during  the  individual  life,  and  that  the 
development  of  the  individual  is  gradual,  its  form,  as  a  rule, 
(•hanging  but  little.  In  respect  of  the  structure  of  the  mouth, 
Ovthoptera  and  Hemiptera  are  the  most  different  of  all  the 
Orders.  Hence,  Hemiptera  is  really  the  most  isolated  of  all  the 
Orders  of  Insects.  We  shall  subsequently  see  that,  like  Orthoptera, 


FIG.  255. — JZnsfhenes 
pratti  (Pentato- 
midae).  China.  A, 
Nymph  :  a,  case  of 
anterior,  b,  of  pos- 
terior wing  ;  c,  ori- 
fices of  stink- 
glands  ;  B,  the 
adult  Insect. 


A 


the  Order  appeared  in  the  Palaeozoic  epoch.  Although  a  very 
extensive  Order,  Hemiptera  have  for  some  incomprehensible 
reason  never  been  favourite  objects  of  study.  Sixty  years  ago 
Dufour  pointed  out  that  they  were  the  most  neglected  of  all  the 
great  Orders  of  Insects,  and  this  is  still  true  ;  our  acquaintance 
with  their  life-histories  and  morphology  especially  being  very 
limited. 

There  is  probably  no  Order  of  Insects  that  is  so  directly  con- 
nected with  the  welfare  of  the  human  race  as  the  Hemiptera  : 
indeed,  if  anything  were  to  exterminate  the  enemies  of  Hemiptera, 
we  ourselves  should  probably  be  starved  in  the  course  of  a  fe\v 
months.  The  operations  of  Hemiptera,  however,  to  a  large  ex- 
tent escape  observation,  as  their  mouth-setae  make  merely  pricks 
that  do  not  attract  notice  in  plants  ;  hence,  it  is  probable  that 


534  HEMIPTERA  CHAP. 

injuries   really   due    to  Hemiptera   are    frequently  attributed    to 
other  causes. 

In  the  course  of  the  following  brief  sketch  of  the  anatomy 
and  development  of  Hemiptera,  we  shall  frequently  have  to  use 
the  terms  Heteroptera  and  Homoptera  ;  we  may  therefore  here 
mention  that  there  are  two  great  divisions  of  Hemiptera  having 
but  little  connection,  and  known  by  the  above  names :  the 
members  of  these  two  Sub-Orders  may  in  most  cases  be  dis- 
tinguished by  the  condition  of  the  wings,  as  mentioned  in  the 
definition  at  the  commencement  of  this  chapter. 

External  structure. — The  mouth-parts  consist  of  an  anterior 
or  upper  and  a  posterior  or  lower  enwrapping  part,  and  of  the 
organs  proper,  which   are  four  hair-like  bodies,  dilated  at   their 
bases    and    resting   on    a    complex    chitiuous    framework.      The 
lower  part  forms  by  far  the  larger  portion  of  the  sheath  and  is  of 
very  diverse  lengths,  and  from  one  to  four-jointed  :  it  is  as  it  were 
an  enwrapping  organ,  and  a  groove  maybe  seen  running  along  it, 
in    addition    to    the    evident    cross  -  segmentation.      The     upper 
covering  part  is  much   smaller,  and   only  fills  a  gap  at  the  base 
of  the  sheath ;  it  can  readily  be  lifted  so  as  to  disclose  the  setae ; 
these  latter  organs  are  fine,  flexible,  closely  connected,  rods,  four 
in  number,  though  often  seeming  to  be  only  three,  owing  to  the 
intimate  union   of  the  components  of  one   of  the  two  pairs ;  at 
their  base  the   setae   become   broader,  and  are  closely  connected 
with  some  of  the  loops  of  the  chitinous  framework  that  is  con- 
tained within  the  head.      Sometimes  the   setae  are  much   longer 
than    the    sheath ;    they   are    capable    of   protrusion.      Although 
varying  considerably  in  minor  points,  such  as  the  lengths  of  the 
sheath  and  setae,  and  the   number   of  cross-joints  of  the  sheath, 
these  structures  are  so  far  as  is  known  constant  throughout  the 
Order.      There  are  no  palpi,  and  the  only  additions  exceptionally 
present  are  a  pair  of  small  plates  that  in  certain  forms  (aquatic 
family  Belostomidae)  lie  on  the  front  of  the   proboscis   near  the 
tip,  overlapping,  in  fact,  the  last  of  the  cross-articulations. 

Simple  as  is  this  system  of  trophi  its  morphology  is  uncertain, 
and  has  given  rise  to  much  difference  of  interpretation.  It  may 
be  granted  that  the  two  portions  of  the  sheath  are  respectively 
upper  lip,  and  labium ;  but  as  to  the  other  parts  wide  difference 
of  opinion  still  prevails.  On  the  whole  the  view  most  generally 
accepted,  to  the  effect  that  the  inner  pair  of  the  setae  correspond 


VIII 


STRUCTURE 


535 


in  a  broad  sense  with  maxillae  of  mandibulate  Insects,  and  the 
outer  pair  with  mandibles,  is  probably  correct.  Mecznikow,  who 
studied  the  embryology,1  supports  this  view  for  Heteroptera, 
but  he  says  (t.c.  p.  462),  that  in  Homoptera  the  parts  of  the 
embryo  corresponding  with  rudimentary  maxillae  and  mandibles 
disappear,  and  that  the  setae  are  subsequently  produced  from 
peculiar  special  bodies  that  are  at  first  of  a  retort-shaped  form ; 
the  neck  of  the  retort  becoming  afterwards  more  elongate  to  form 
the  seta;  also  that  in  the  Heteropterous  genus  Gerris  the 
embryology  in  general  resembles  that  of  Homoptera,  but  the 


77k 


clr 


n 


rncl  mx 


FIG.    256.— Mouth  -  parts    of 
Hemiptera.  (After 

Wedde.)  A,  Section  of 
the  head  and  proboscis  of 
Pyrrhocoris  apterus  :  d/\ 
gland;  i.g,  infra  -  oeso- 
phageal  ganglion;  Ib, 
labium  ;  Ir,  labrum ;  m, 
muscles  ;  m1,  muscle  (de- 
pressor of  labium) ;  m2, 
muscle  of  syringe  ;  ph, 
pharynx  ;  s,  setae  ;  s.g, 
supra  -  oesophageal  gang- 
lion ;  s£>.  dr,  salivary 
gland  ;  spr,  syringe :  B, 
transverse  section  of  pro- 
boscis of  Pentatoma  ruji- 
pes,  at  third  joint  of 
sheath  :  m,  m,  muscles  ; 
md,  mandibular  seta  ;  mx, 
maxillary  setae  ;  n,  nerve  ; 
2),  the  sheath  or  labium  ; 
tr,  trachea. 


development  of  the  setae  is  like  that  of  other  Heteroptera  (t.c.  p. 
478).  This  discontinuity  in  the  development  of  the  Homopterous 
mouth  has  since  been  refuted  by  Witlaczil,2  who  found  that  the 
retort-shaped  bodies  really  arise  from  the  primary  segmental 
appendages  after  they  have  sunk  into  the  head.  We  are  there- 
fore justified  in  concluding  that  the  mouth-parts  are  at  first 
similarly  developed  in  all  Hemiptera,  and  that  this  development 
is  of  a  very  peculiar  nature. 

Smith  is  convinced  that  there  are  no  traces  of  mandibular 
structure  in  any  Hemiptera.3  On  the  other  hand,  numerous 
entomologists  have  supposed  they  could  homologise  satisfactorily 
various  parts  of  the  Hemipterous  trophi  with  special  parts  of  the 

1  Zdtschr.  wiss.  Zool.  xvi.  1866,  p.  389.          -  Arb.  List.   Wien.  iv.   18S2,  p.  415. 
.3  Tr.  Amcr.  Phil.  Sue.  xix.  1896,  p.  176. 


536  HEMIPTERA  CHAP. 

maxillae  and  labium  of  maudibulate  Insects.  This  point  has 
recently  been  discussed  by  Marlatt :  and  by  Heymons."  From 
the  latter  we  gather  that  the  mode  of  growth  is  peculiar  by  the 
extension  backwards  of  some  of  the  sclerites,  and  their  becoming 
confounded  with  parts  of  the  wall  of  the  head.  From  all  this  it 
appears  that  at  present  wre  cannot  correctly  go  farther  than 
saying  that  the  trophi  of  Hemiptera  are  the  appendages  of  three 
head-segments,  like  those  of  other  Insects.  The  views  of  Savigny, 
Leon,3  and  others  to  the  effect  that  labial  palpi,  and  even  other 
parts  of  the  labium  of  Mandibulata  can  be  satisfactorily  identified 
are  not  confirmed  by  Heymons. 

Underneath  the  pharynx,  in  the  head,  there  is  a  peculiar 
structure  for  which  we  have  as  yet  no  English  term.  It  was 
apparently  discovered  by  Landois  and  Paul  Mayer,4  and  has  been 
called  "  Wanzenspritze,"  which  we  translate  as  syringe.  It  may  lie 
briefly  described  as  a  chamber,  into  which  the  salivary  ducts  open, 
prolonged  in  front  to  the  neighbourhood  of  the  grooves  of  the 
sdiie  in  the  rostrum;  behind,  it  is  connected  with  muscles; 
it  has  no  direct  connection  with  the  pharynx,  and  though  it  was 
formerly  supposed  to  lie  an  organ  of  suction,  it  seems  more  prob- 
able that  it  is  of  the  nature  of  a  force-pump,  to  propel  the  pro- 
ducts of  some  of  the  bug's  glands  towards  the  tips  of  the  setae. 

The  rostrum  being  extended  from  its  position  of  repose,  the 
tip  of  the  sheath  is  brought  into  contact  with  the  object  to  be 
pierced,  the  surface  of  which  is  probably  examined  by  means  of 
sensitive  hairs  at  the  extremity  of  the  sheath  ;  these  therefore 
functionally  replace  to  some  extent  the  palpi  of  other  Insects. 
As  a  rule  the  sheath  does  not  penetrate  (though  there  is  reason 
for  believing  that  in  various  of  the  animal-feeding  bugs  it  does 
so),  but  the  setae  are  brought  into  action  for  piercing  the  skin 
of  the  plant ;  they  are  extremely  sharp,  and  the  outer  pair  are 
usually  barbed,  so  that  when  once  introduced  a  hold  is  easily 
maintained.  This  being  established  it  is  thought  that  the  salivary 
pump  comes  into  play,  and  that  a  fluid  is  injected  into  the  object 
pierced  so  as  to  give  rise  to  irritation  or  congestion,  and  thus 
keep  up  a  supply  of  fluid  at  the  point  operated  on  :  this  fluid 
extends  along  the  grooved  setae  by  capillary  attraction,  and  the 

1  P.  cut.  soc.   Washington,  iii.  1895,  p.  241.         "  Ent.  Xacltr.  xxii.  1896,  p.  173. 

3  Zool.  Anz.  1897,  No.  527,  p.  73. 
4  Arch.  Anat.  Physiol.  1874,  p.  313,  and  1875,  p.  309. 


VIII 


STRUCTURE 


537 


rapidity  of  the  current  is  increased  by  a  pumping  action  of  the 
pharynx,  and  possibly  by  movements  of  the  setae  themselves. 
Though  the  setae  are  often  extremely  elongate — sometimes  several 
times  the  length  of  the  body — they  are  nearly  always  slender,  arid 
there  is  no  reason  to  suppose  that  a  perfect,  or  air-tight,  tube  is 
formed ;  hence  it  is  probable  that  capillary  attraction  is  really 
the  chief  agent  in  the  ingestion  of  the  fluid.  The  slight  diversity 
of  structure  of  the  Hemipterous  trophi  is  in  very  striking  con- 
trast with  what  we  find  in  mandibulate  Insects,  and  in  the  less 
purely  suctorial  Insects,  such  as  Diptera  and  some  divisions  of 
Hymenoptera.  Schiodte  in  com- 
menting on  this  has  suggested  that 
it  is  probably  due  to  the  small  variety 
of  actions  the  rostrum  is  put  to.1 

The  head  exhibits  great  variety 
of  form ;  in  the  Homoptera  the 
front  part  is  deflexed  and  inflexed, 
so  that  it  is  placed  on  the  under 
surface,  and  its  anterior  margin 
is  directed  backwards  ;  it  is  often 
peculiarly  inflated  ;  in  the  Lantern- 
flies  or  Fulgoridae  (Fig.  282)  to  an 
incomprehensible  extent.  In  the  great 
Water-bugs,  Belostomidae,  there  is  on 
the  under  surface  a  deep  pocket  for 
each  antenna,  beautifully  adapted  to 
the  shape  of  the  curiously- formed  ap- 
pendage (Fig.  279).  The  prothorax  is 
always  very  distinct,  frequently  large, 
and  in  many  of  the  Heteroptera 
(Fig.  257),  as  well  as  in  the  Homop-  FlG-  257.— .%cc«Ze«w  tuberculatus 

,_5  Gray.    Brazil.    (Fam.  Reduvndae.) 

terOUS      family,     Membracidae     (Jblg.          (Antennae  absent  in  the  specimen 

283),  assumes  the  most  extraordinary       represented.) 
shapes.      Both  ineso-  and  meta-thorax  are  well  developed.      The 
former   is   remarkable   for   the   great   size   of   the   scutellum ;    in 
some  cases  (Flataspides,  Scutellerides)  this  forms  a  large  process, 

1  For  the  structure  and  development  of  the  Hemipterous  trophi,  see  Mayer,  Arch. 
Anat.  Physiol.  1874  and  1875  ;  Mecznikow,  Zcitschr.  iviss.  Zool.  xvi.  1866,  p.  389  ; 
Geise,  Arch.  Naturgesch.  xlix.  1,  1883,  p.  315  ;  AVedde,  op.  cit.  li.  1,  1885,  p.  113  ; 
Mark,  Arch.  mikr.  Anat.  xiii.  1877,  p.  31  :  Smith,  Tr.  A  met:  Phil.  Sue.  xix.  1896, 
p.  176. 


538  HEMIPTERA 


CHAP. 


that  entirely  covers  and  conceals  the  alar  organs,  so  that  the 
Insect  has  all  the  appearance  of  being  apterous.  The  exact  coin- 
position  of  the  abdomen  has  not  been  satisfactorily  determined, 
opinions  varying  as  to  whether  the  segments  are  nine,  ten,  or 
eleven  in  number.  The  difficulty  of  determining  the  point 
is  due  to  two  facts :  viz.  the  extreme  modification  of  the  terminal 
segments  in  connection  with  the  genital  appendages,  and  the 
prominence  of  the  extremity  of  the  alimentary  canal.  If  this 
terminal  projection  is  to  be  treated  as  a  segment,  it  would  appear 
that  eleven  segments  exist,  at  any  rate  in  some  cases ;  as  the 
writer  lias  counted  ten  distinct  segments  in  a  young  Coreid  bug, 
in  addition  to  the  terminal  tube.  This  tube  in  some  of  the  male 
Heteroptera  is  very  subject  to  curious  modifications,  and  has 
been  called  the  rectal  cauda.  Verhoeff  considers  that  ten  seg- 
ments were  invariably  present  in  the  females  examined  by  him 
in  various  families  of  Heteroptera  and  Hornoptera.1  In  Aphidae 
(a  division  of  Homoptera),  Balbiani  considers  there  are  eleven 
abdominal  segments  present ;  but  he  treats  as  a  segment  a  pro- 
jection, called  the  cauda,  situate  over  the  anus  ;  this  structure  docs 
not  appear  to  be  homologous  with  the  rectal  cauda  we  have  just 
mentioned.  In  Coccidae  the  number  of  abdominal  segments  is 
apparently  reduced.  Schiodte  states  2  that  the  older  authorities 
are  correct  in  respect  of  the  stigmata  ;  there  are,  he  says,  in 
Heteroptera  invariably  ten  pairs;  one  for  each  thoracic  segment: 
and  seven  abdominal,  placed  on  the  ventral  face  of  the  pleural 
fold  of  the  abdomen.  In  some  cases  there  are  additional  orifices 
on  the  external  surface  that  have  been  taken  for  stigmata,  though 
they  are  really  orifices  of  odoriferous  glands ;  these  openings  may 
exist  on  the  metasterna  or  on  the  dorsal  surface  of  the  abdomen. 
The  lateral  margins  of  the  abdomen  are  frequently  greatly  de- 
veloped in  Heteroptera,  and  are  called  "  connexivum  ; "  the  upper 
and  lower  surfaces  of  the  body  meeting  together  far  within  the 
marginal  outline.  Dr  Anton  Dohrn  many  years  ago 3  called  atten- 
tion to  the  extremely  remarkable  structure  of  the  terminal  segments 
in  many  male  Hemiptera  ;  and  the  subject  has  been  subsequently 
very  imperfectly  treated  by  the  present  writer  and  other  ento- 
mologists, but  it  has  never  received  the  attention  it  deserves. 

Ent.  Xaclir.  xix.  1893,  p.  369. 

\nttu-ltixt.    Tulskr.    (3)  vi.   1896  ;  translated  in  Ann.  X.   Hist.  (4),  vi.  1870, 
p.  '225.  :i  Ent.  Zeit.  Stettin,  xxvii.  1806,  p.  321. 


VIII 


STRUCTURE 


539 


The  anterior 


In  the  females  of  numerous  Heteroptera  and  Homoptera 
(Capsidae,  Cicadidae,  etc.)  there  is  a  well-developed  ovipositor,  that 
serves  both  as  a  cutting  instrument  to  make  slits  in  the  stems 
of  plants,  and  as  a  director  to  introduce  the  eggs  therein.  Yerhoeff 
considers  that  it  always  consists  of  two  pairs  of  processes  (though 
one  pair  may  be  very  small),  one  from  the  eighth  abdominal 
segment,  the  other  from  the  ninth.1 

The  antennae  usually  have  very  few  joints,  often  as  few  as 
four  or  five,  their  maximum  number  of  about  twenty-five  being 
attained  in  the  males  of  some  Coccidae,  this  condition  being, 
however,  present  in  but  fewr  of  even  this  family.  In  Belostoma 
(Fig.  279)  they  assume  extremely  curious  forms,  analogous  to 
what  we  find  in  the  Coleopterous  germs  Hydrophilus.  In  addi- 
tion to  the  compound  eyes,  there  are  usually  ocelli,  either  two  or 
three  in  number,  but  wanting  in  many  cases.  The  usual  number 
of  joints  of  the  tarsi  is  three,  but  in  Coccidae  there  is  only  one 
joint. 

The  wings  (Fig.  258)  exhibit  much  diversity, 
pair  usually  differ  greatly  from  the  pos- 
terior ;  they  are  called  elytra,  hemi-elytra 
or  tegmina.  This  difference  in  the  two 
pairs  is  the  rule  in  the  first  of  the  great 
divisions  of  the  Order,  and  the  name 
Heteroptera  is  derived  from  the  fact.  In 
this  Sub-Order  the  front  wings  close  over 
the  back,  and  are  more  or  less  horny,  the 
apical  part  being,  however,  membranous., 
Systematists  make  use  of  the  wings  for 
the  purpose  of  classification  in  Heterop- 
tera, and  distinguish  the  following  parts, 
"  clavus,"  "  corium,"  "  membrane,"  the 

corium  being  the  larger  horny  division,  FIG.  258.— Alar  organs  of  a 
the  clavus  the  part  lying  next  the  scu- 
tellum  and  frequently  very  sharply  dis- 
tinguished from  the  corium ;  the  mem- 
brane is  the  apical  part.  The  outer 
or  costal  part  of  the  wing  is  also  often 

sharply  delimited,  and  is  called   the  "  embolium  ; "   in   the   great 
family   Capsidae  and    a  few  others,   the  outer  apical  part  of  the 

1   Ent.  Nachr.  xix.  1893,  p.  375. 


Capsid  bug  (Capsus  lani- 

arius).  A,  Elytron  :  A. 
clavus  ;  B,  corium  ;  c, 
cuneus  ;  D,  membrane  ; 
E,  E,  cell  of  the  mem- 
brane :  B,  hind-wing. 


54O  HEMIPTERA  CHAP. 

corium  is  differentiated  from  the  rest  of  the  surface,  and  is  termed 
the  "  cuneus."  In  Plataspides,  one  of  the  divisions  in  which 
the  alar  organs  are  entirely  covered  by  the  scutellum,  they  are 
modified  in  a  very  remarkable  manner.  In  the  Homoptera  the 
divisions  named  above  do  not  exist,  and  the  wings  in  repose  are 
placed  in  a  different  position,  as  stated  in  our  definition  of  the 
Order.  It  is  said  to  be  very  difficult  to  homologise  the  wing- 
nervures  of  Hemiptera,  and  nothing  appears  to  be  known  as  to 
the  mode  of  their  development. 

The  alar  organs  in  Hemiptera  exhibit  a  very  frequent  form 
of  variation  within  the  limits  of  the  same  species  ;  this  has  not 
yet  been  elucidated.1  In  some  cases  in  the  Heteroptera  nearly 
all  the  individuals  of  a  generation  may  have  the  wings  aborted  ; 
sometimes  this  occurs  as  a  local  variation.  In  Aphidae  the 
occurrence  of  winged  and  wingless  individuals  is  very  common, 
and  has  even  become  an  important  factor  in  their  extraordinary 
life  cycles.  (See  Chermes,  etc.,  subsequently.) 

Internal  anatomy. — The  alimentary  canal  presents  consider- 
able diversity  and  some  remarkable  features.  There  is  a  slender 
tube-like  oesophagus  and  a  large  crop.  It  is  difficult  to  assign 
any  of  the  parts  posterior  to  this  to  the  divisions  usual  in 
other  Insects,  and  it  is  said  that  the  distinction  of  parts  histo- 
logically  is  as  vague  as  it  is  anatomically.  In  the  Heteroptera 
the  Malpighian  tubes  open  into  two  (or  one)  vesicular  dilatations 
seated  immediately  in  front  of  the  short  rectum :  between  this 
point  and  the  crop  there  may  be  a  very  elongate,  slender  portion 
with  one  or  more  dilatations,  these  parts  apparently  replacing 
the  true  or  chylific  stomach.  There  is  no  gizzard.  In  the 
Homoptera  the  relations  of  the  divisions  of  the  alimentary  canal 
are  even  more  puzzling ;  the  canal  is  elongated  and  forms  coils, 
and  these  are  connected  with  tissues  and  tunics  so  as  to  make 
their  dissection  extremely  difficult.  List  says  that  there  are 
great  differences  in  the  alimentary  canal  among  the  members 
of  the  one  family  Coccidae.  There  are  usually  four  Malpighian 
tubes,  but  in  Coccidae  there  is  only  one  pair,  and  in  Aphidae 
none.  The  excretory  cells  of  these  tubes  are  in  Hemiptera  of 
remarkably  large  size.  There  is  a  large  development  of  salivary 
glands,  at  least  two  pairs  existing.  There  can  be  little  doubt 
that  some  of  their  products  are  used  for  purposes  of  injection,  as 

1  On  tliis  subject,  see  Reuter,  Ann.  Soc.  ent.  France  (5)  v.  1875,  p.  225. 


vni  STRUCTURE  541 

already  described,  though  Klinckel  came  to  the  conclusion  that 
the  saliva  when  placed  in  living  plants  is  totally  innocuous.1 

The  ganglia  of  the  nervous  system  are  all  concentrated  in 
the  thorax  and  head.  In  some  cases  (in  various  Homoptera)  the 
infra-oesophageal  ganglion  is  placed  at  a  distance  from  the  supra- 
oesophageal  ganglion,  and  may  even  be  united  with  the  thoracic 
mass  of  ganglia  (Ortkezia,  etc.) ;  in  this  case  the  chitinous  frame- 
work of  the  mouth-parts  is  interposed  between  the  supra-  and 
the  infra-oesophageal  ganglia.  In  Pentatoma  all  the  three  gan- 
glionic  masses  are  brought  into  close  proximity,  but  in  Nepa  the 
thoracic  mass  of  ganglia  and  the  infra-oesophageal  ganglion  are 
widely  separated. 

The  ovarian  tubes  vary  greatly  in  number :  according  to  List 
in  Orthezia  cataphracta  the  number  differs  considerably  in  dif- 
ferent individuals,  and  even  in  the  two  ovaries  of  the  same 
individual,  the  number  being  usually  ten.  The  testes  are  not 
placed  in  a  common  tunic,  though  they  are  frequently  approxi- 
mated or  even  contiguous.2 

The  smell  of  bugs  is  notorious.  In  many  species  it  is  not 
unpleasant,  though  as  a  rule  it  is  decidedly  offensive.  It  is  a 
remarkable  fact  that  the  structures  connected  with  the  production 
of  this  odour  are  different  in  many  cases  in  the  young  and  in 
the  adult.  The  odour  emitted  by  the  latter  proceeds  from  a  sac 
seated  at  the  base  of  the  abdomen,  and  opening  exteriorly  by 
means  of  an  orifice  on  each  side  of  the  inetasternum ;  while  in 
the  young  there  are  two  glands  situated  more  dorsally  and  a 
little  more  backwards,  and  opening  on  two  of  the  dorsal  plates 
of  the  abdomen  (Fig.  255,  A).3  In  the  young  the  dorsum  of  the 
abdomen,  where  the  stink-glands  open,  is  exposed,  but  this  part 
in  the  adult  is  covered  by  the  wings.  The  odorific  apparatus  is 
specially  characteristic  of  Heteroptera,  and  Kiinckel  states  that 
there  is  so  much  variety  that  generic  and  even  specific  characters 
might  be  drawn  from  conditions  of  the  stink -glands.  As  a  rule 
they  are  most  constantly  present  in.  the  plant-feeding  forms  ;  in 
some  essentially  carnivorous  forms  (Eeduviidae,  Xepidae,  Xoto- 

1  Ann.  Soc.  ent.  France  (4)  vii.  1867,  p.  45. 

'•  The  chief  work  on  the  internal  anatomy  of  Hemiptera  is  still  Dufour's  Rc- 
cherches  anatom-iqucs  et  pkysiulogiqucs  sur  Ics  Htimipteres,  3fe>n.  Surans  Strangers, 
Paris,  iv.  1833,  p.  129. 

3  Kiinckel,  Ann.  Soc.  ent.  France  (4)  vii.  1867,  p,  45,  and  L'.JL  Ac.  Paris,  cxx. 
1895,  p.  1002. 


542  HEMIPTERA  CHAP. 

nectidae)  they  are  entirely  absent.      The  offensive  matter  emitted 
by  Notonecta  is   of  a  different   nature,  and   is  probably  anal  in 


origin. 


Metamorphosis    or   postembryonic    development. — In  the 

language  of  the  systematists  of  metamorphosis,  Hemiptera  are 
said  to  be  Homomorpha  Paurometabola  —  that  is,  the  young 
differ  but  little  from  the  adult.  According  to  Brauer's  general- 
isations they  are  Menorhynchous,  Oligonephrous,  Pterygogenea, 
i.e.  they  have  a  sucking  mouth  that  does  not  change  during  life, 
few  Malpighian  tubes,  and  are  winged  in  the  adult  state.  It  is 
generally  admitted  that  the  Homoptera  do  not  completely  agree 
with  Heteroptera  in  respect  of  the  metamorphosis,  it  being 
more  marked  in  the  former,  and  in  Coccidae  attaining  (as  we 
shall  mention  when  discussing  that  family)  nearly*  if  not  quite 
the  condition  of  complete  metamorphosis  of  a  peculiar  kind. 
Unfortunately  we  are  in  almost  complete  ignorance  as  to  the 
details  of  the  life-histories  and  development  of  Heteroptera,  so 
that  we  can  form  no  generalised  opinion  as  to  what  the  post- 
embryonic  development  really  is  in  them,  but  there  are  grounds 
for  supposing  that  considerable  changes  take  place,  and  that 
these  are  chiefly  concentrated  on  the  last  ecdysis.  The  young  of 
some  bugs  bear  but  little  resemblance  to  the  adult;  the  magnifi- 
cently-coloured species  of  JEustlienes  (Fig.  255),  before  they  attain 
the  adult  condition  are  flat,  colourless  objects,  almost  as  thin  as  a 
playing-card  ;  it  is  well  known  that  the  extraordinary  structures 
that  cover  and  conceal  the  body  in  Plataspides,  Scutellerides, 
Membracides,  etc.,  are  developed  almost  entirely  at  the  last  moult : 
it  is  not  so  well  known  that  some  of  these  changes  occur  with  much 
rapidity.  A  very  interesting  account  of  the  processes  of  colour- 
change,  as  occurring  in  Poecilocapsus  lineatus  at  the  last  ecdysis, 
has  been  given  by  Lintner,1  and  from  this  it  appears  that  the 
characteristic  coloration  of  the  imago  is  entirely  developed  in 
the  course  of  about  two  hours,  forming  a  parallel  in  this  respect 
with  Odonata.  When  we  come  to  deal  with  Aphidae  we  shall 
describe  the  most  complex  examples  of  cycles  of  generations  that 
exist  in  the  whole  of  the  animal  kingdom. 

Fossil  Hemiptera. — Hemiptera  are  believed  to  have  existed 
in  the  Palaeozoic  epoch,  but  the  fossils  are  not  numerous,  and 
opinions  differ  concerning  them.  Eugercon  hockingi,  a  Per- 

1  In  Slingeiiand's  Cornell  Univ.  Bull.  No.  58,  1893,  p.  222. 


VIM  FOSSIL    FORMS CLASSIFICATION  543 

mian  fossil,  was  formerly  supposed  to  be  a  Homopterous  Insect, 
but  it  is  very. anomalous,  and  its  claim  to  a  position  in  Hemip- 
tera  is  denied  by  Brauer,1  who  considers  it  to  be  Orthopterous. 
It  is  now  generally  recognised  that  this  fossil  requires  complete 
reconsideration.  Another  Permian  fossil,  Fulgorina,  is  admitted 
to  be  Homopterous  by  Scudder,  Brauer  and  Brongniart.  Scudder 
thinks  the  Carboniferous  Pkthanocoris  was  an  Archaic  Hetero- 
pterous  Insect,  and  if  correct  this  would  demonstrate  that  both  of 
the  two  great  Sub-Orders  of  Hemiptera  existed  in  Palaeozoic  times. 
Brauer,  however,  is  inclined  to  refer  this  fossil  to  Homoptera,  and 
Brongniart 2  speaks  of  it  as  being  without  doubt  a  Fulgorid. 
Dictyocicada,  Ehipidioptera  and  Meganostoma,  from  the  Carboni- 
ferous shales  of  Commentry,  have  also  been  referred  to  Fulgoridae 
by  Brongniart,  but  the  evidence  of  their  alliance  with  this  group 
is  far  from  satisfactory.  In  the  Secondary  epoch  numerous 
Hemiptera  existed,  and  are  referred  to  several  of  the  existing 
families.  They  come  chiefly  from  the  Oolite.  In  the  Eocene  of 
the  Isle  of  Wight  a  fossil  has  been  discovered  that  is  referred  to 
the  existing  Homopterous  genus  Triecphora. 

We  are  not  entitled  to  conclude  more  from  these  facts  than 
that  Homoptera  probably  appeared  before  Heteroptera,  and  date 
back  as  far  as  the  Carboniferous  epoch. 

Classification  and  families. — No  complete  catalogue  of 
Hemiptera  exists,  but  one  by  M.  Severin  is  in  course  of  publica- 
tion. It  is  probable  that  there  are  about  18,000  species  at 
present .  described,  two-thirds  of  this  number  being  Heteroptera. 
In  Britain  we  have  about  430  species  of  Heteroptera  and  600 
of  Homoptera.  The  classification  of  the  Order  is  not  in  a  very 
advanced  condition.  The  following  table  exhibits  the  views  of 
Schiodte 3  in  a  modified  form  :— 

Front  of  head  not  touching  the  coxae.  I.    HETEROPTERA. 

Front  of  head  much  inflexed  so  as  to  be  in  contact  with  the  coxae. 

II.   HOMOPTERA. 

Sub-Order  I.   HETEROPTERA. 

Posterior  coxae  nearly  globose,  partly  embedded  in  cavities,  and  having 
a  rotatory  movement.  Mostly  terrestrial  forms.  1 .  Trochalopoda. 

Posterior  coxae  not  globose,  larger,  and  not  embedded;  their  articulation 
with  sternum  almost  hinge-like.  Posterior  aspect  of  hind  femur  usually 

1  SB.  Ak.   Wien.  xci.  1  AUh.,  1SS5,  p.  275. 
2  Lcs  Insectcs  fossiles,  etc.,  1894,  p.  452.         ::  Ann.  .\'«f.  Hist.  (4)  vi.  1870,  p.  225. 


544  HEMIPTERA  CHAP. 

more  or  less  modified  for  the  reception  of  the  tibia  when  closed  on  it  :  mostly 
aquatic  forms.  2.  Pagiopoda. 

Division  1.   TROCHALOPODA. 

This  division  includes  the  majority  of  the  families  of  Heteroptera — viz. 
the  whole  of  the  terrestrial  families  except  Saldidae,  and  it  also  includes 
Nepidae,  a  family  of  water-bugs. 

Division  2.   PAGIOPODA. 

This  includes  the  six  purely  aquatic  families  of  Heteroptera,  except 
Nepidae,  which  appear  to  have  very  little  connection  with  the  other  aquatic 
bugs.  The  only  terrestrial  Insects  included  in  the  family  are  the  Saldidae  ; 
in  these  the  femora  are  not  modified  as  they  are  in  the  aquatic  forms. 
Hemiptera  that  live  on  the  surface  of  water,  not  in  the  water,  are  classed 
with  the  terrestrial  species.  With  these  exceptions  this  arrangement  agrees 
witli  that  of  Gymnocerata  and  Cryptocerata  as  usually  adopted,1  and 
therefore  followed  in  the  following  pages.  Schiodte's  characters,  moreover, 
d<>  not  divide  his  two  divisions  at  all  sharply. 

Sub-Order  II.   HOJIOPTERA. 

Tarsi  usually  three-jointed  .  <•  .     Series  Trimera. 

,,  ,,        two-jointed  .          ,,      Dimera. 

„  „        of  one  joint  .  .          ,,       Monomera. 

The  classification  of  Homoptera  is  in  a  most  unsatisfactory  state  ;  2  no  two 
authors  are  agreed  as  to  the  families  to  be  adopted  in  the  series  Trimera. 
We  have  recognised  only  five — viz.  Cicadidae,  Fulgoridae,  Membracidae, 
Cercopidae,  and  Jassidae.  The  Dimera  consists  of  Psyllidae,  Aphidae, 
Aleurodidae  ;  and  the  Monomera  of  Coccidae  only.  It  is  usual  to  associate  the 
Dimera  and  Monomera  together  under  the  name  of  either  Phytophthires  or 
Sternorhyiicha,  but  no  satisfactory  definition  can  be  given  of  these  larger 
groups,  though  it  seems  probable  that  the  families  of  which  they  are  com- 
posed are  natural  and  distinct. 

Sub-Order  I.   HETEROPTERA. 

Series  1.  Gymnocerata. 

The  majority  of  the  terrestrial  families  of  Heteroptera  form 
the  series  Gymnocerata,  in  which  the  antennae  are  conspicuous, 
and  can  be  moved  about  freely  in  front  of  the  head,  while  in 

1  A  table  of  the  families  is  given  by  Ashmeacl,  but  does  not  work  out  quite 
satisfactorily,  Entom.  Americana,  iv.  1888,  p.  65  ;  a  brief  table  of  the  characters 
of  the  British  families  is  given  by  Saunders,  Hem-iptera- Heteroptera  af  the  British 
Islands,  1892,  p.  12. 

!  Those  who  wish  to  see  tables  of  the  families  are  referred  to  Ashmead,  loc. 
cit.  ;  to  Pascoe,  Ann.  Nat.  Hist.  (5)  ix.  1882,  p.  424;  to  Still's  Hemiptera  Afri- 
cana,  vol.  iv.  1866  ;  and  for  the  families  found  in  Britain  to  Edwards,  Hemiptera- 
Jfonioptera  of  the  British  Ixl<ui<ls.  For  a  discussion  in  Danish  on  the  value  of  the 
characters  used,  cf.  Haiisen,  Ent.  Tidskr.  xi.  1890,  pp.  19-76. 


VIII 


HETEROPTERA PENTATOMIDAE 


545 


Cryptocerata  they  are  hidden.  The  series  Crymnocerata  includes 
all  the  terrestrial  Heteroptera,  and  the  two  families,  Hebridae 
and  Hydrometridae,  which  live  on  the  surface  of  the  water  or  in 
very  damp  places ;  while  Cryptocerata  includes  all  the  forms  that 
live  under  water. 

Fam.  1,  Pentatomidae. — Scutellum  very  large,  at  least  half 
as  long  us  the  abdomen,  often  covering  the  whole  of  the  after-body 
and  alar  appendages.  Antennae  often  Jive-jointed.  Proboscis- 
sheath  four  -jointed.  Ocelli  two.  Each  tar  sal  claw  -with  an 
appendage. — This,  the  largest  and  most  important  family  of  the 
Heteroptera,  includes  upwards  of  4000  species,  and  an  immense 
variety  of  forms.  It  is  divided  into  no  less  than  fourteen  sub- 
families. The  species  of  one  of  these,  Plataspides,  are  remarkable 
for  their  short,  broad  forms,  and  the  peculiar  condition  of  the 
alar  organs,  which  are  so  completely 
concealed  by  the  great  scutellimi  that 
it  is  difficult  to  believe  the  Insects  are 
not  entirely  apterous.  The  head  is  usually 
inconspicuous  though  broad,  but  in  a 
few  forms  it  is  armed  with  horns. 
Though  this  sub-family  includes  upwards 
of  200  species,  and  is  very  widely  dis- 
tributed in  the  Old  World,  it  has  no 
representatives  in  America.  The  Scutel- 
lerides  also  have  the  body  covered  by 
the  scutellum,  but  their  organs  of  flight 
are  less  peculiar  than  they  are  in  the 
Plataspides  ;  the  Insects  of  this  sub- 
family are  highly  remarkable  on  account 
of  their  varied  and  frequently  vivid  coloration ;  some  of  them 
are  metallic,  and  the  colour  of  their  integuments  differs  greatly 
in  some  cases,  according  to  whether  the  specimen  is  wet  or 
dry  ;  hence  the  appearance  after  death  is  often  very  different 
from  that  of  the  living  specimen.  These  Insects  are  extremely 
numerous  in  species.  The  sub- family  Phloeides  (Fig.  259),  on 
the  contrary,  includes  only  three  or  four  South  American 
species:  they  have  no  resemblance  at  all  to  other  Pentatomidae  : 
they  are  flat,  about  an  inch  long,  and  look  like  scales  of  bark, 
in  this  respect  agreeing  with  Ledra  and  some  other  Homoptera. 
The  South  American  sub-family  Cyrtocorides  (Fig.  260)  is  of 

VOL.  vi  2  N 


FIG.  259. — Phloea  corticata. 
South  America. 


546 


HEMIPTERA-HETEROPTERA 


CHAP. 


mon- 


FIG.    260. — Cyrtocoris 

.*fi-"si<s.       South      America, 
x  3. 


equally  small  extent ;  the  species  are  of  strange  irregular   shapes, 
for  which  we  can  iind  no  reason.      The   Tessaratomides  includes 

many  of  the  largest  Hemiptera-Hetero- 
ptera,  some  of  its  members  attaining 
two  inches  in  length. 

The  great  family  Pentatomidae,  con- 
taining  about  400  species,  is  represented 
in  Britain  by  about  36  native  species, 
the  most  interesting  of  which  are  perhaps 
those  of  the  genus  A.cantJiosonfia.  De 
Geer  noticed  long  ago  that  the  female  of 
A.  yriscuni  exhibits  great  solicitude  for 
its  young,  and  his  statement  has  since 
been  confirmed  by  Mr.  Parfitt  and  the 
Eev.  J.  Hellins,  who  found  that  the 
mother  not  only  protects  the  eggs  but 
also  the  young,  and  that  for  a  considerable  time  after  hatching.1 

Very  little  is  known  as  to  the  life-histories  of  Pentatomidae. 
In  some  cases  the  young  are  very  different  in  appearance 
from  the  adults.  The  peculiar  great  scutellum  is  not  developed 
till  the  mature  condition  is  reached.  But  little  attention  has 
been  given  to  the  habits  of  Pentatomidae ;  it  is  generally  con- 
sidered that  they  draw  their  nutriment  from  plants ;  the 
American  Euthyrhynclius  floridanus  has,  however,  been  noticed 
to  suck  the  honey-bee,  and  we  think  it  probable  that  a  good 
many  Pentatomids  will  be  found  to  attack  Insects. 

The  term  Pentatomidae  as  applied  to  this  family  is  of  modern 
origin  :  in  most  books  the  equivalent  group  is  called  Scutata,  or 
Scutati,  and  the  term  Pentatomidae  is  restricted  in  these  works 
to  the  sub-family  called  Pentatomides  in  the  system  wre  adopt. 

Fam.  2.  Coreidae. — Scutellum  not  reaching  to  the  middle  of 
the  body  ;  proboscis-sheath  four-jointed ;  ocelli  present ;  inifninae 
i/i  /if rally  elongate  and  four-jointed,  inserted  on  the  upper  parts 
of  the  sides  of  the  head ;  femora  not  knobbed  at  the  tip. — The 
members  of  this  great  family  are  easily  recognised  by  the  above 
characters  ;  formerly  it  was  called  Supericornia  in  connection  with 
the  characteristic  position  of  the  antennae.  About  1500  species 
are  known,  and  they  are  arranged  in  no  less  than  twenty-nine 
sub-families.  Many  of  them  are  Insects  of  large  size,  and  they 


1   lint.  Ihuj.  vii.  1870,  p.  53. 


VIII 


HETEROPTERA COREIDAE 


547 


frequently  have  a  conspicuous  disc,  or  dilatation,  on  one  of  the 
joints  of  the  antennae.  Another  very  curious  and,  as  yet,  inex- 
plicable peculiarity  very  commonly  met  with  among  them,  is 
that  the  hind  legs  may  be  of  great  size  and  deformed ;  either  the 
femora  or  the  tibiae,  or  both,  being  very  much  distorted  or 
armed  with  projections.  Brilliant  colour  is  here  comparatively 
rare,  the  general  tone  being  indefinite  tints  of  browns,  greys,  or 
smoky  colours.  The  South  American  genus  Holymenia  (Copius 


FIG.  261. — Diactor  bilineatus. 
South  America.       x  -3. 


FIG.  262.- — Phyllomorpha  laciniata,  carry- 
ing some  of  its  eggs.     Spain. 


of  older  authors)  consists  of  slender  forms,  having  the  elytra 
transparent  even  on  the  basal  part  like  Homoptera  ;  this  and 
some  other  peculiarities  give  the  species  of  this  genus  a  certain 
resemblance  to  Insects  of  other  Orders ;  Westwood  says  that 
Diateina  liolymenoicles  (Diptera)  greatly  resembles  a  bug  of  the 
genus  Holymenia.  The  tropical  American  genus  Diactor  consists 
of  a  few  species  of  elegant  colour  having  the  hind  legs  very 
peculiarly  shaped,  the  tibiae  being  flattened  and  expanded  in  a 
sail-like  manner,  and  ornamented  with  agreeable  colours  different 


IIEMIPTERA-HETEROPTERA  CHAP. 

from  those  on  the  rest  of  the  body ;  they  are  made  more  con- 
spicuous by  the  femora  being  remarkably  long  and  thin  ;  it  is 
probable  that  they  are  used  as  ornaments.  The  sub -family 
Phyllomorphides  consists  of  about  a  dozen  species,  and  is  found 
in  several  of  the  western  parts  of  the  Eastern  hemisphere,  one 
species,  P.  laciniata,  occurring  in  Southern  Europe.  This  Insect  is 
of  very  delicate  texture,  and  the  sides  of  the  body  are  directed 
upwards  and  deeply  divided  so  that  a  sort  of  basin  is  formed,  of 
which  the  dorsum  of  the  body  is  the  floor ;  the  Insect  is  very 
spinose,  and  is  thus  enabled  to  carry  its  eggs,  the  spines  helping 
to  retain  them  in  position  on  the  back.  It  is  said  to  be  the  male 
that  thus  carries  the  eggs.  This  species  is  able  to  stridulate, 
and  when  doing  so  vibrates  its  antennae  with  excessive  rapidity. 
We  have  only  about  a  score  of  species  of  Coreidae  in  Britain, 
and  none  of  the  remarkable  forms  of  the  family  are  among  them. 
Fam.  3.  Berytidae.--Fm/  slender  Insects  with  the  first 
joint  of  the  antennae  and  the  femora  thickened  at  the  tips.— 
This  small  family  was  not  distinguished  from  Coreidae  by  the 
older  authors.  It  consists  of  about  fifty  species,  eight  of  which 
are  found  in  Britain. 

Fam.  4.  Lygaeidae. — The  characters  are  the  same  as  those 
mentioned  for  Coreidae,  except  as  regards  the  insertion  of  the 
antennae;  the  upper  surface  or  face  of  the  head  is  not  so  flat,  ~but 
is  transversely  convex,  so  that  seen  in  profile  the  antennae  app«/r 
to  l>e  inserted  well  down  on  the  sides  of  the  head. — The  name 
Infericornia  was  formerly  applied  to  these  Insects.  They 
are  on  the  average  of  smaller  size  than  the  members  of  the 
Coreidae  or  Pentatomidae,  and  are  much  less  conspicuous  in  colour 
and  form  ;  a  good  many  of  the  larger  Lygaeids  arc,  however, 
variegate  with  black,  yellow,  and  red.  The  family  is  very  numerous 
in  species,  about  1400  being  known;  they  are  arranged  in 
thirteen  sub-families;  we  have  about  sixty  species  in  Britain, 
nearly  all  small.  Eremocoris  lives,  when  immature,  in  the  nests 
of  the  wood-ant,  according  to  Wasmann.  The  family  includes 
some  notorious  Insect-pests.  The  Chinch -bug,  Blissus  leuco- 
/ifi-rus,  commits  very  serious  ravages  on  corn  and  grasses  in  North 
America.  The  Cotton-stainer,  Dysdercus  suturellus  is  also  very 
injurious  to  cotton  in  certain  parts  of  the  New  AVoiid  :  its  growth 
has  been  described  by  Iviley,1  who  thinks  a  dye  valuable  for 

1  Insect  Life,  i.  1889,  p.  234. 


vin  LVGAEIDAE — PYRRHOCORIDAE- -TINGIDAE  549 

commercial  purposes  might  be  procured  from  the  Insect.  This 
bug  has  recently  developed  the  habit  of  sucking  oranges,  and  has 
thus  become  injurious  in  Florida,  as  the  fruit  readily  decays 
after  it  has  been  punctured  by  these  Insects.  The  phenomenon 
of  "  micropterism  "  is  exhibited  by  numerous  Lygaeids,  as  well  as 
by  Pyrrhocoridae. 

Fam.  5.  Pyrrhocoridae. — Distinguished  from  Lygaeidae  only 
by  the  absence  of  ocelli,  and  not  recognised  as  a  distinct  family 
by  all  Hemipterists.  About  300  species  are  included.  Our 
only  British  member  is  the  notorious  Pyrrhocoris  apterus ;  it  is, 
however,  very  rare  in  this  country,  though  it  abounds  on  the 
Continent,  and  has  been  the  object  of  investigation  by  embryo- 
logists  and  others.  It  displays  in  a  most  marked  manner  the 
curious  dimorphism  as  to  the  alar  organs  that  is  so  common  in 
certain  divisions  of  Hemiplera  ;  the  elytra  and  wings  being  some- 
times normally  developed,  while  in  other  cases  the  wings  are 
entirely  absent,  and  the  horny,  basal  part  of  the  elytra  only  is 
present.  In  some  localities,  and  in  some  years,  only  the  micro- 
pterous  form  is  found,  while  on  other  occasions  there  may  be  a 
large  percentage  of  the  macropterous  form.  The  abundance  of 
this  Insect  has  enabled  the  French  chemist  Physalix  to  obtain 
an  amount  of  its  colouring  matter  sufficient  for  analysis ;  as 
the  result  he  procured  a  substance,  insoluble  in  water,  very 
closely  allied  to  carotine.1  The  Oriental  Insect  Loliita  grandis  is 
one  of  the  most  remarkable  of  Bugs,  the  male  of  the  Sumatran 
variety  being  over  two  inches  in  length,  having  enormously  long 
antennae,  and  the  abdomen  extended  to  about  twice  the  normal 
length,  while  the  other  sex  is  in  the  usual  condition  in  these 
respects.  The  species  is  said  to  be  injurious  to  the  cotton-plant 
in  India. 

Fam.  6.  Tingidae. — Tarsi  tivo-jointed.  Elytra  more  or  less 
•i-i  /Iculate,  consisting  of  strong,  irregular,  thick  lines  forming  a  frame- 
work of  cells,  the  enclosed  part  of  the  cell  being  of  different  texture 
" /id  frequently  transparent;  antennae  with  terminal  joint  more  or 
less  knob-like,  the  fweceding  joint  very  long  ;  ocelli  wanting ;  pro- 
notum  prolonged  behind,  covering  the  scutelhim ;  front  coxae  placed  «f 
the  back  of  the  thorax. — This  is  the  first  of  a  series  of  families 
with  only  two  joints  to  the  feet.  These  little  bugs  are  very 
remarkable  objects,  and  exhibit  much  variety  in  their  peculiar 

1   C.E.  Ac.  Sci.  Paris,  cxviii.  1894,  p.  1282. 


550 


HEMIPTERA-HETEROPTERA 


CHAP. 


sculpture,  which  in  numerous  forms  attains  a  condition  of 
elegance  well  worthy  of  attention.  There  are  nearly  300  species 
known,  and  in  Britain  we  have  about  a  score.  The  characters 
we  have  given  above  do  not  apply  to  the  genus  Piesma,  though 

it  is  usually  placed  in 
this  family ;  its  scutel- 
lum  is  not  covered,  and 
ocelli  are  present.  Al- 
though but  little  is 
known  as  to  the  nature 
of  the  lives  of  Tingidae, 
yet  it  was  pointed  out 
long  ago  by  Reaumur 
that  a  species  of  the 
family  (probably  C.  clavi- 
corne,  Fig.  263),  lives  in 
deformations  of  the 
flowers  of  the  Labiate 


FIG.  263. -—Copium  cJaricorne. 
( After  Riibsaamen.) 


x8 


Europe. 


plant  now  called  Teucrium  cliamaedrys ;  Frauenfeld  has  more 
recently  confirmed  this  observation,  and  shown  that  the  closely  allied 
C.  teucrii  affects  the  flowers  of  T.  montant/m  in  a  similar  manner.1 
Fam.  7.  Aradidae.--TWy  Jiat,  broad;  scutellutii  exposed, 
large  or  moderate ;  «l>duttie/i.  l>rt.>«<lrr  f/ian.  t//c  ala/-  a,';/'/ /is,  which  it 
frequent  1 1/  em-axes  like  a  broad  frame,  front  coxae  placed  in  the 
middle  of  the  prosternum. — These  very  flat  Insects,  of  obscure  colour, 
have  frequently  very  peculiar  sculpture.  They  live  under  bark,  or 
on  fungi  growing  from  bark,  and 
are  supposed  to  draw  their  nut- 
riment from  the  fungi,  though 
but  little  is  actually  known  as 
to  their  natural  history.  The 
family  is  almost  cosmopolitan, 
;u id  includes  about  300  species, 
of  which  five  occur  in  Eng- 
land. The  small  sub -family 
Isoderminae  consists  of  a  few 
species  that  are  placed  only 

1,      •       .        vi          ,1  Kn;.  264. — Arculus  orientalis.     Siam. 

provisionally  in  Aradidae;  they 

differ  from  the  normal  members  by  there  being  no  groove  on  the 

1   Vcrli.  G'cs.   jy-icn.  iii.  1858,  p.  157. 


VIII 


ARADIDAE IIEBRIDAE HVDROMETRIDAE 


551 


breast,  so  that  the  rostrum  is  free.  Of  the  five  species,  three 
occur  in  Chili  and  Patagonia,  two  in  Tasmania,  and  one  in 
Australia. 

Fam.  8.  Hebridae. — -Minute  bugs,  of  semiaquatic  habits, 
clothed  beneath  with  a  dense,  minute,  silvery  pubescence ;  antennae 
five-jointed  ;  legs  of  not  more  than  average  length  ;  elytra  in  larger 
part  membranous. — This  small  family  consists  altogether  of  only 
about  a  dozen  species ;  we  have  two  species  of  the  genus  Hebrus 
in  Britain ;  they  are  usually  found  in  very  wet  moss. 

Fam.    9.     Hydrometridae. — Form    very    diverse;     antennae 
l'« a, --jointed,  tarsi  two-jointed.      Coxae  usually  widely    separated. 
Either  wingless  or  with  elytra  of  one  texture  throughout,  having 
no  membranous  part.      Under  surface  with  a  minute  velvet -lih'e 
pubescence.      In  many  forms  the  legs  are  of  great  length. — Although 
of   comparatively  small  extent — scarcely   200   species  being  at 
present  known — this  family  is  of  great 
interest  from  the  habit  possessed  by  its 
members    of   living    on    the    surface   of 
water.      Iii   the  case    of   the    notorious 
genus  Halobates  (Fig.  265)   the  Insects 
can  even  successfully  defy  the   terrors 
of    Neptune    and    live    on    the    ocean 
many    hundreds    of    miles    from    land. 
There   is   great  variety  of  form  among 
Hydrometridae.       The    European     and 
British    genus    Mesovelia    is    of    short 
form,    and    but    little    dissimilar   from 
ordinary  land-bugs,  with  which,  indeed, 
it  is  connected  by  means  of  the  genus 
Hebrus,     already     noticed.        Mesovelia 
represents  the  sub-family  Mesoveliides, 
which,  though   consisting  of  only  four 
species,  occurs  in  both  hemispheres,  and 
in  the  tropics  as  well  as  in  the  tern- 
perate  regions.      Our  species,  M.  furcate , 
walks  on  the  surface  of  the  water,  the 
movements  of  its    legs    and    the    posi- 
tion of  its  coxae   being   those   of  land -bugs.     Another   British 
Insect — the    highly  remarkable   Hydrometra  stagnorum — is    of 
excessively  slender  form,  with  long  thin  legs,  by  aid  of  which  it 


.  265.  —  ITalohates  sdbriimx. 
Under  surface  of  a  female 
carrying  eggs.  Pacific  Ocean 
(Marquesas). 


552  HEMIPTERA-HETEROPTERA  CHAP. 

walks  on  the  surface-film  of  water,  above  which  its  body  is  held 
well  separated.  It  is  easily  drowned,  and  if  submerged  it  has 
great  difficulty  in  escaping  from  the  water.  This  genus  repre- 
sents the  sub -family  Hydrometrides,  and  is  apparently  almost 
cosmopolitan.  Vdia  currens  is  another  common  British  Insect  ; 
it  loves  the  eddies  and  currents  of  backwaters  on  burns  and 
streams,  and  is  very  abundant  in  Scotland.  An  American  ally, 
Rhagovdia  plumbea,  appears  to  be  not  uncommon  on  the  surface 
of  the  ocean  in  the  Gulf  of  Mexico,  near  the  shores.  The  great 
majority  of  the  family  belong  to  the  division  Gen-ides,  of  which 
the  curious,  long  Insects  that  float  so  lazily  and  skim  so  easily 
on  the  surface  of  quiet  streams  are  typical.  The  species  of  the 
genus  now  called  Gerris,  but  formerly  known  as  Hydrometra  are 
apparently  distributed  all  over  the  world ;  we  have  ten  in 
Britain.  They  have  very  long  legs,  and  on  being  alarmed  move 
away  with  the  greatest  ease. 

The  genus  Hcddbates  includes  at  present  fifteen  species.  They 
are  found  on  the  ocean,  where  the  surface-water  is  warm,  in 
various  parts  of  the  world.  They  are  destitute  of  any  trace  of 
alar  organs,  the  meso-  and  meta-thorax  are  closely  united  and 
Lirge,  while  the  abdomen  is  very  small,  so  that  the  body  is  of 
oval  form  ;  the  middle  legs  are  thrown  so  far  back  that  they  are 
placed  immediately  over  the  posterior  pair.  When  the  sea  is 
calm  these  Insects  skim  over  the  surface  with  rapidity,  but 
disappear  as  soon  as  it  becomes  agitated.  They  are  believed  to 
feed  on  small  animals  recently  deceased ;  Witlaczil  says  011 
the  juices  of  jelly-fish.  The  young  are  frequently  met  with, 
and  there  can  be  no  doubt  that  the  whole  life-cycle  may  be 
} »; i  ssed  through  by  the  Insect  far  away  from  land.  The  Italian 
ship  Vcttor  Pisani  met  with  a  bird's  feather  floating  on  the 
ocean  off  the  Galapagos  Islands,  covered  with  eggs  which  proved 
to  be  those  of  Halolmtes  in  an  advanced  stage  of  development. 
It  was  formerly  believed  that  the  female  carries  the  eggs  for 
some  time  after  their  exclusion,  and  although  this  has  since 
been  denied,  it  is  nevertheless  an  undoubted  fact,  for  it  was 
observed  by  Mr.  J.  J.  Walker,1  to  whom  we  are  indebted  for 
a  specimen  having  the  eggs  still  attached  to  the  body,  as  shown 
in  Fig  2G5.  Mr.  Walker  believes  the  bugs  shelter  themselves 
when  the  sea  is  at  all  rough  by  keeping  at  a  sufficient  distance 

1  Ent.  May.  xxix.  1893,  y.  227. 


I II 


HYDROMETRIDAE 


553 


below  the  surface  ;   they  can  dive  with  facility,  and  are  gregarious. 

They  are  frequently   found  close  to  the  shore,  and  Mr.  Walker 

has  even   met   with   them   on  land.      The   stink-glands  of  other 

Hemiptera     are     said 

by    Nassonoff    to    be 

replaced   in   Haloltates 

by     peculiar     ventral 

glands.        An      allied 

genus,    Halobatodcs, 

was    siipposed    to    be 

oceanic,    but     this    is 

not  the  case,  some  of 

the      species      having 

been  found  recently  in 

fresh   water   in   India, 

and    others    in    estu- 

aries at  Port  Darwin. 

A    remarkable     allied 

form,    Hcrmatolates 

Jiaddoni,  was  recently 

discovered      by      Pro- 

fessor      Haddon       in 

Torres  Straits.     Apart 

from  the  oceanic  life, 

Halolates     is     by    no 

means    the    most    ex- 

traordinary  of  the 

Hydrometridae. 

Javanese 

laticaudata        repeats 

some     of    its    peculi- 

arities, and  is  of  larger  size,  with   the   sexes  very  different.      The 

most  remarkable  of  the  family  is  perhaps  the   fresh-water  genus 

Rheumatobates  (Fig.    266),    in  which    the   males    have   peculiar 

prehensile  antennae  that  look  like  legs.      These  curious   Insects 

inhabit  North  America  and  the  West  Indies. 

We  may  here  notice  an  enigmatic  Insect  called  Hemidiptera 
J/aeckeli  by  Leon.  From  the  single  specimen  known  it  is  con- 
cluded that  the  Insect  has  only  one  pair  of  wings,  and  that  they 
are  attached  to  the  metathorax.  It  is,  however,  possible,  as 


The 


FIG.  266. — Rheumatobates  bergrothi.       <  10. 
West  Indies.     (After  Meinert.) 


554 


HEMIPTERA-HETEROPTERA 


CHAP. 


suggested     by    Bergroth,1    that     the    anterior    pair    have    been 
detached  by  some  accident. 

Fam.  10.  Henicocephalidae. — Head  swollen  behind  the 
eyes  so  as  to  form  a  sort  of  globe,  on  the  anterior  part  of 
which  the  ocelli  are  placed.  Rostrum  extremely  short.  Elytra 
rather  large,  of  one  consistence  throughout ;  conspicuously  veined.— 
There  is  only  one  genus ;  it  is  very  widely  distributed,  about  a 
dozen  species  being  known  ;  one  of  these  occurs  in  the  south  of 
Europe.  These  curious  little  bugs  appear  to  be  most  nearly 
allied  to  the  Eeduviidae.  According  to  Westwood  and  others 
they  are  somewhat  gregarious ;  a  Tasmanian  species  dances  in 
the  air  after  the  fashion  of  midges  or  May-flies,  and  dispenses  an 
agreeable,  musk-like  odour. 

Fam.  11.  Phymatidae. — Front  legs  of  peculiar  structure,  short 
and  stout,  with  long  coxae,  short  thick  femora,  and  tibiae  curvate, 
pointed  ;  frequently  without  tarsi. — The  Insects  of  this  family  are 


^'-W^f 


FIG.  267. — Cnrcinocoris  butyhami  (Phymatidae).     Burma. 

believed  to  be  predaceous,  the  structure  of  the  legs  being  such  as 
is  called  raptorial,  and  one  species,  Phi/mata  erosa,  being  known 
to  capture  and  suck  honey-bees  in  North  America.  There  are 
only  about  seventy  species  of  Phymatidae  known.  We  have 

1    JJ'icn.  cut.  Zcif.  xi.  1892,  p.  169. 


VIII 


THYMATIDAE REDUVIIDAE 


555 


none   in   Britain,   though   there  are   a  few  in  Southern  Europe  ; 

one  of  these,  P.  crassipes,  extends   as   far  north  as   Paris.      The 

distinction  of  the  family  from   Eeduviidae  is  doubtful.1      There 

are  a  few  very  rare  forms  (Fig.  267)  in  which  the  front   tibia   is 

articulated  to  the  femur  in 

such  a  way  that  a  pair  of 

pincers  is  formed  :  the  tarsus 

is  in   this   form,  as  well  as 

in  some  other  Phymatidae, 

absent. 

Fam.  12.  Reduviidae. 
—Head  more  or  less  don- 
gate,  very  movable,  eyes  placed 
much  in  front  of  the  thorax, 
ocelli,  when  present,  behind 
the  eyes.  Proboscis  short,  or 
moderately  short,  not  ex- 
tending on  to  the  breast,  in 
repose  curved  under  the  head 
so  as  to  form  a  loop  there- 
with .  Elytra,  wh en  presen  t, 
consisting  of  three  divisions. 
Tarsi  three-jointed. — This  is 
one  of  the  largest  and  most 
important  families  of  Hemi- 
ptera.  Upwards  of  2000 
species  are  already  known  ; 
the  habits  seem  to  be  chiefly 
of  a  predaceous  nature,  the 
creatures  drawing  their 
nutriment  from  the  animal 
rather  than  from  the  vege- 
table kingdom,  and  their 
chief  prey  being  in  all 
probability  other  kinds  of  Fm_  z^_GhiUaneUa  #/,•,„/,•/.<.  Brazil.  A. 

Insects.        There  is,   perhaps,          the  female  Insect.     B,  extremity  of  the  l.o.h 

no  family  of  Insects  exhibit- 
ing a  greater  variety  of  form  and  colour. 


of  the  male. 

The  Emesids  are  amongst 

the   most  delicate  of  Insects,  equalling  in  this  respect  the  daddy- 
1  Monograph  of  Phymatidae :  Handlirsch,  Ann.  Hofmus.  Jl'u-n,  xii.  1897,  p.  127. 


556 


HEMIPTERA-HETEROPTERA 


CHAP. 


long-leg  flies ;  they  are,  however,  highly  predaceous  ;  their  front 
legs  are  peculiarly  formed  for  capturing  and  holding  their  prey,  and 
have  long  coxae,  like  Mantis,  so  that  these  Insects  are  commonly 
mistaken  for  small  or  young  Mantises,  from  which  their  sucking 
proboscis  at  once  distinguishes  them.  This  curious  starved-look- 
ing  form  of  bug  reaches  its  maximum  of  peculiarity  in  the  South 

American  genus  Ghili- 
anella  (Fig.  268).  Ac- 
cording to  Pascoe  the 
linear  form  enables  the 
young  larva  to  be  carried 
about  by  the  mother, 
the  long  slender  abdo- 
men of  the  larva  being 
curled  around  the 
thorax  of  the  parent. 
Ploiaria  -pallida,  from 
Woodlark  Island,  is 
an  Insect  of  excessive 
fragility  and  elegance, 
with  the  long  thin  legs 
coloured  with  alternate 
patches  of  black  on  a 
white  ground,  giving 
rise  to  a  very  curious 
appearance  remarkably 
analogous  to  what  we 
find  in  some  of  the 
equally  delicate  daddy- 
long-leg  flies. 

We  have  three  species  of  Emesides  in  Britain,  but  most  of  our 
Reduviidae  belong  to  the  sub-family  Nabides.  These  approxi- 
mate to  ordinary  bugs  in  appearance  and  characters  more  than 
do  any  other  of  the  Reduviidae.  One  of  our  indigenous  Nabides 
is  of  great  interest  from  the  curious  resemblance  it  has  to  an  ant 
(Fig.  269).  The  likeness  is  brought  about  by  the  sides  of  the 
b;ise  of  the  abdomen  being  very  pallid  in  colour,  except  a  dark 
mark  in  the  middle  ;  this  mark  is  in  shape  like  the  pedicel  of  an 
ant.  Viewed  in  profile  it  is  found  that  on  the  base  of  the  abdo- 
ineii  there  is  an  elevation  like  the  "  scale  "  in  this  position  in 


FIG.  269. — JVc/'/x  liifli-i'iitrift,  young.     Cambridge. 
A,  Insect  seen  from  above  ;  B,  profile. 


VIII 


REDUVIIDAE 


557 


ants,  and  that  the  abdomen  is  extremely  ant-like  in  form.  This 
resemblance  is  quite  parallel  with  that  of  an  Orthopteroii  to  an 
ant  (see  Vol.  V.  p.  323);  the  Insect  is  by  no  means  uncommon, 
and  it  is  strange  that  this  curious  case 
of  resemblance  should  hitherto  have 
escaped  notice.  The  bug  runs  about  on 
plants  and  flowers,  and  is  frequently  in 
company  with  ants,  but  we  do  not  know 
whether  it  preys  on  them.  Not  the 


FIG.  270. — Ptilocnemus  sidnicus. 
Australia.     (After  Mayr.) 

least  remarkable  of  the 
facts  connected  with 
this  Insect  is  that  the 
resemblance  is  confined 
to  the  earlier  instars  ; 
the  adult  bug  not  being 
like  an  ant.  AVe  may 
here  mention  that  there 
are  numerous  bugs  that 
closely  resemble  ants, 
and  that  on  the  whole 
there  is  reason  to  be- 
lieve that  the  resem- 
bling forms  are  actually 
associated  during  life, 
though  we  really  know 
very  little  as  to  this  last 
point. 

The  little  sub-family 
Holoptilides,       with 
twenty-five  species,  but 
FIG.  27i.—Myiodocha  tipuiina.    China.  widely     distributed     in 

the  Eastern  hemisphere,  is  remarkable  on  account  of  the  feathered 


558  IIEMIPTERA-HETEROPTERA  CHAP. 

antennae  and  legs  of  its  members  (Fig.  270).  Altogether  four- 
teen sub-families  are  recognised,  the  most  extensive  one  beino- 

o  o 

Harpactorides,  including  a  great  variety  of  remarkable  forms ;  in 
the  South  American  genus  Notocyrtus  (better  known  as  Saccoderes, 
Fig.  257),  the  prothorax  is  swollen  and  covers  the  body  to  a 
greater  or  less  extent  in  the  fashion  of  a  hood.  In  Yolinus 
and  Eulyes  the  coloration  is  the  most  conspicuous  system  that 
could  be  devised,  the  sides  of  the  abdomen  (connexivum)  being 
expanded  into  bright -red  lobes  on  which  are  placed  patches 
of  polished -black.  The  most  remarkable  form  of  Reduviid 
is,  perhaps,  one  from  China  (Fig.  271)  of  considerable  size, 
of  great  fragility,  and  greatly  resembling,  like  some  Emesides, 
a  daddy-long-legs  fly,  though  it  does  not  belong  to  the  Emes- 
ides. It  is  an  altogether  anomalous  form.  According  to 
Seitz  there  is  found  on  the  Corcovado  in  Brazil  a  Eeduviid 

that  exactly  resembles  one  of  the 
dark  stinging-wasps  of  the  genus 
Pepsis,  and  the  bug  makes  the  same 
sort  of  movements  as  the  wasp  does, 
though  these  are  of  a  kind  quite 
different  from  those  of  ordinary  bugs.1 
Although  the  attacks  of  Redu- 
viidae  on  animals  are  usually  con- 
fined to  the  smaller  and  more 

FIG.  2 1 2. — Eggs  of  Endochus  cinga-     ,    ,          ,          .  .     ,  . 

tensls.      "The    eggs  are    attached    deleiiceless    kinds,  yet    this    IS   Dy  110 

to  a  leaf  and  to  each  other  by  a  means    invariably    the    case  ;    there 

viscid    siibstance  ;    eggs    red,   the 

cover  pale  yellow,  with  the  club  are  in  fact  numerous  species  that  do 
white  at  the  tip."-MS.  note  of       t  iiesitate  to   attack  man  himself. 

E.  E.  Green. 

Several  species  of  Eeduvius  do   this 

in  Southern  Europe,  and  are  frequently  met  with  in  houses.  E. 
personatus  is  the  only  species  of  the  genus  in  England  ;  though 
far  from  common  anywhere,  it  is  sometimes  found  in  houses,  and 
is  said  to  destroy  the  common  bed-bug ;  it  is  able  to  pass  its 
whole  existence  in  our  habitations,  for  the  young  are  found  as 
frequently  as  the  adult,  and  are  usually  concealed  by  a  quantity 
of  dusty  matter,  or  refuse,  adhering  to  the  body.  This  habit  of 
covering  the  body  with  some  foreign  substance  is  natural  to  the 
Insect,  the  young  that  are  found  on  trees  being  covered  with 
matter  derived  therefrom.  Darwin  has  given  us  an  account  of 

1  Ent.  Zcit.  Stettin,  li.  1890,  p.  281. 


vin  AEPOPHILIDAE CERATOCOMBIDAE — CIMICIDAE         559 

the  Benchucha,1  a  bug  an  inch  long,  which  in  South  America 
attacks  human  beings  after  the  fashion  of  the  common  bed-bug. 
In  this  case  no  ill-effects  follow  the  attack,  but  in  the  case  of 
Conorhinus  sanguisuga  in  Arizona,  great  pain  and  inflammation 
ensue  and  may  end  in  the  gathering  and  discharge  of  pus. 

Not  the  least  remarkable  of  characters  of  Reduxiidae.  is  the 
form  of  the  eggs  of  some  of  the  species  (Fig.  272,  and  Vol.  A'. 
Fig.  78,  C) ;  the  egg  bearing  a  peculiar  operculum,  the  purpose  of 
which  is  at  present  quite  mysterious. 

Fam.  13.  Aepophilidae. — A  single  species  forms  this  family. 
It  is  of  considerable  interest,  as  it  is  incapable  of  flight,  passing  a 
large  part  of  its  life  covered  by  the  sea.  Aepophilus  bonnairei 
is  a  small  Insect  with  quite  short  head,  without  ocelli,  and  with 
the  organs  of  flight  represented  by  a  pair  of  very  short  elytra, 
with  rounded  hind-margins.  It  is  found  on  the  shores,  of 
Western  France,  and,  as  a  great  rarity,  on  our  own  south  coast. 
It  no  doubt  sucks  small  soft  animals.  In  the  Channel  Islands 
it  occurs  in  spots  where  it  is  nearly  always  covered  by  a  con- 
siderable depth  of  water. 

Fam.  14.  Ceratocombidae. — Minute  bugs  with  ocelli  and 
elytra.  Eostrum  free.  Head  not  broad,  somewhat  prolonged  in 
front;  eyes  close  to  the  thorax.  Elytra  usually  without  a  dis- 
tinctly separated  membrane.  Tarsi  three-jointed. — This  family 
includes  at  present  only  a  few,  minute,  fragile  bugs,  that  have 
often  been  classified  with  Cimicidae  or  Anthocoridae.  We  have 
only  two  British  species,  one  of  which,  Dipsocoris  alienus,  is 
common  amongst  the  damp  shingle  at  the  margins  of  the  burns 
and  waters  of  Scotland. 

Fam.  15.  Cimicidae. — Ocelli  absent ;  elytra  very  short  and 
broad,  so  that  the  broad  abdomen  is  left  uncovered.  Head  short 
and  broad.  Eostrum  received  in  a  groove  beneath  the  head.  Tarsi 
three-jointed. — Although  this  family  consists  of  only  a  dozen 
species,  it  is  the  most  notorious  of  all  the  Order,  as  it  includes 
the  detestable  Cimex  lectularius  or  common  Bed-bug.  This  Insect 
is  now  peculiar  to  the  habitations  of  man,  and  is  said  not  to 
trouble  savage  races ;  or  rather  it  is  supposed  to  be  present  only 
when  the  habitations  have  a  certain  degree  of  comfort  and  per- 
manence. It  has  no  fixed  period  of  the  year  fur  its  development, 
but  the  generations  succeed  one  another  so  long  as  the  temperature 

1  Naturalist's  Voyage,  ed.  1884,  p.  330  ;  chap.  xv. 


560 


HEMIPTERA-HETEROPTERA 


CHAP. 


is  sufficiently  elevated ;  during  too  cold  weather  the  Insects 
merely  become  stupefied,  their  lives  being  as  it  were  interrupted 
till  warmth  returns.  It  is  a  favourite  food  with  other  Insects, 
and  is  destroyed  by  cockroaches  and  ants  as  well  as  by  Redurius ; 
the  small  black  ant  Monomorium  will,  it  is  said,  clear  a  house  of  the 
bed-bug  in  a  few  days.  Nothing  is  really  known  as  to  the  origin 
of  this  Insect ;  it  is  now  very  widely  distributed.  The  other 
species  of  the  family  frequent  birds  and  bats,  and  are  very 
similar  to  the  common  bug.  The  genus  to  which  the  bed-bug 
belongs  is  in  many  works  called  Acanthia  instead  of  dim  <. 
Other  authors  apply  the  term  Acanthia  to  Sal  da,  but  it  is  better 
to  allow  the  name  Acanthia  to  fall  into  disuse. 

Fam.  16.  Anthocoridae. — Minute  buys,  usually  with  ocelli 
and  with  elytra;  the  latter  occasionally  abbreviated,  ~but  usually 
fully  developed,  with  membranous  ttj>.  Head  prolonged  in  tie 
middle  in  front  much  beyond,  the  insertion  of  the  antennae;  eyes 
not  far  from  the  thorax.  Rostrum  free. — These  small  and  obscure 
Insects  appear  to  be  rather  numerous  in  species,  and  to  be  chiefly 
connected  with  woods  and  forests.  Some  of  the  species  live 

in  ants'  nests.  We  have  27 
British  species  belonging 
to  11  genera.  About  200 
species  of  the  family  are 
known.  The  members  of 
the  sub-family  Microphy- 
sides  are  remarkable  from 
the  great  dissimilarity  of 
the  sexes,  for  which  it  is 
not  possible  to  assign  any 
reason. 

Fam.  17.  Polyctenidae. 
-  Proboscis  -  sheath     th  ree  - 
jointed,    tarsi  four -jointed, 
a nte n  /me  fun  r-jni  nted.     Te<j- 
/nina  yuite  short,  of  one  con- 
sistence.— The  four   or   five 
anomalous    species   forming 
this  family  are  parasites  on 

bats  of  the  genus   Molossus,  and   have  been   found   in   both   the 
Eastern  and  Western  hemispheres.    Westwood,  who  first  described 


FIG.  273. — Polyctenes  f 
(After  Westwood.) 


VIII 


POLYCTENIDAE CAPSIDAE 


56l 


them,1  treated  them  as  aberrant  Anoplura  or  Lice,  but  there  do 
not  appear  to  be  any  sufficient  grounds  for  removing  these  para- 
sites from  Hemiptera-Heteroptera.  The  condition  of  their  alar 
organs  reminds  one  of  what  exists  in  'Cimex  and  Aepophilus,  and 
the  mouth  is  not  known  to  possess  any  very  peculiar  structure. 
We  have  had  no  opportunity  of  making  a  thorough  examination 
of  Poli/i'leiK-x,  and  therefore  speak  with  some  diffidence. 

Fam.  18.  Capsidae. — Moderate-sized  or  small  bugs,  of  delicate 
consistence,  wif/io//t  ocelli  ;  the  elytra  and  wings  usually  large  in 
proportion  to  the  body,  the  former  with  two  cells  (occasionally/ 


FIG.  274. — Hdopdtis  sp.     East  India. 

only  one}  in  the  membrane.  Antennae  four-jointed,  the  second  joint 
•usually  very  long,  the  terminal  two  more  slender  than  the  others. 
The  proboscis  not  received  in  a  groove.  Sc^itell^cm  exposed,  m«<!<  - 
rately  large.  Tarsi  three-jointed.  Female  with  an  ovipositor 
en l>al>le  of  exsertion. — This  family  is  one  of  the  most  extensive  of 
the  Hemiptera;  we  have  about  170  species  in  Britain,  where 
they  are  most  abundant  in  the  south.  The  exotic  species  have 
.been  but  little  collected.  Their  colours 
are  usually  delicate  rather  than  vivid, 
and  are  never  metallic.  They  frequent 
plants  of  all  kinds,  and  many  of  them 
skip  by  the  aid  of  their  wings  with  great 
agility  in  the  sunshine.  The  majority 
pr<  »1  tal  ily  suck  the  juices  of  the  plants,  but 
some  are  known  to  prey  on  other  Insects. 
The  species  of  the  Indian  genus  Helo- 

1  Flo.  275. — Section  of  ;\  st.-m  with 

(rig.    2(4)    are    remarkable    by        egg  of  ;.  Capsid  bug  allied 

tO     //•/«/(.'/'/<     I  Mors;i    Mi-Ill  i. 


A.fter  Dudgeon.) 


possessing  a  knobbed  spine  projecting 
straight  up  from  the  scutellum,  making 
the  individual  look  as  if  it  were  a  specimen  with  a  pin  through 

1   T/ti-s'iiin/s  t'/if.  Oxoniensis,  1^71,  j>.  li>7. 
VOL.  VI  2  0 


562  HEMIPTERA-HETEROPTERA  CHAP. 

it :  they  attack  the  tea-plaut  and  do  considerable  damage.  They 
are  known  as  Mosquito-blight.  The  egg  is  of  comparatively  large 
size,  and  is  placed  by  the  bug  in  the  stems  of  the  tea-plant, 
but  attached  to  one  end  of  the  egg  are  two  long  slender  threads 
that  project  externally.  A  similar  egg  (Fig.  275)  and  method 
of  oviposition  have  been  described  by  Mr.  Dudgeon  as  occurring 
in  another  species  of  Capsidae,  called  Moesa-blight,  in  India.1 

Fam,  19.  Saldidae. — Head  short  and  broad,  with  large,  pro- 
minent eyes.  Ocelli  present.  Proboscis  not  applied  to  under  surface 
of  head  or  breast  in  repose.  Scutellum  large,  not  covered.  Elytra 
covering  the  upper  surface  of  the  abdomen,  formed  of  three  distinct 
parts.  Tarsi  three-jointed. — These  little  bugs  run  with  velocity 
over  mud  in  damp  places,  or  live  in  wet  moss ;  some  of  them  can 
jump  ;  they  are  all  of  dark  or  obscure  colour.  There  are  only 
three  genera  :  Salda,  of  which  we  have  numerous  British  species, 
being  the  principal  one. 


Series  2.  Cryptocerata. 

The  remaining  families  of  Heteroptera  are  of  aquatic  habits, 
and  form  in  nearly  all  works  a  separate  division  called  Hemiptera 
Cryptocerata  (or  Hydrocorisae,  or  Hydrocores),  distinguished  by 
the  antennae  being  apparently  absent ;  they  are,  however,  really 
present,  being  situate  on  the  under  side  of  the  head,  to  which 
they  are  closely  pressed,  or  in  some  cases  placed  in  a  pocket  in 
front  of  each  eye.  There  are  six  of  these  families.  Schiodte 
is  doubtless  correct  in  treating  this  division  as  an  unnatural  one  ; 
it  is,  however,  generally  adopted,  and  is  convenient  for  the  pur- 
poses of  nomenclature  and  arrangement. 

Fam.  20.  Galgulidae  or  Pelogonidae. — Form  short  and 
broad  ;  head  very  broad,  with  prominent  eyes,  ocelli  present.  Hind 
legs  thin,  formed  for  running. — The  Insects  of  this  family  are 
but  little  known ;  they  are  only  sub-aquatic  in  habits,  frequent- 
ing damp  places  at  the  margins  of  streams  and  waters.  The 
presence  of  ocelli  distinguishes  them  from  other  water-bugs,  with 
which  indeed  the  Galgulidae  appear  to  be  but  little  related. 
There  are  only  about  twenty  species  of  the  family  known.  "We 
possess  none  in  Britain;  but  one,  Pelogonus  maryinatus,  occurs 

1  Ind.  Mus.  Notes,  iii.  No.  5,  189-1,  p.  53. 


VIII 


CRYPTOCERATA NEPIDAE 


563 


in  South  Europe.      The  other  members  of  the   family  are  very 
widely  scattered  over  the  surface  of  the  earth. 

Fam.  21.  Nepidae. — Abdomen  furnished  behind  with  a  long 
slender  siphon ;  front  legs  more  or  less  elongate  for  capturing 
l>i-fji,  /i/t/eed  quite  «/•  flic  j'ro/if 
edge  of  the  prothorax. — This 
family  consists  of  two  interest- 
ing but  very  dissimilar  genera, 
Nepa  and  Ranatra.  Both  are 
widely  distributed  over  the 
earth,  and  are  rather  numerous 
in  species.1  We  have  one 
species  of  each  genus  in  Britain. 
Nepa  cinerea,  the  common 
"  water  -  scorpion,"  is  one  of 
the  commonest  of  Insects  in 
Southern  Britain,  living  con- 
cealed in  shallow  waters  when' 
nearly  or  quite  stagnant. 
Ranatra  linearis  (Fig.  276)  is 
much  less  common,  and  appears 
to  be  getting  rarer ;  it  is  not  re- 
corded from  farther  north  than 
Cambridge. 

The  nature  of  the  respir- 
atory arrangements  in  these 
Insects  is  of  considerable  in- 
terest ;  the  long  tube  at  the 
extremity  of  the  body  consists 
of  two  parts  (as  shown  in  Fig. 
276)  brought  together  in  the 
middle,  one  from  each  side. 
Lacaze-Duthiers  states  that  the  FIG.  276— ^/,////,-//  linearis,  with  the  two 

portions,    «.,    of    the    respiratory    siphcu 

processes  are  elongated  pleurae,        separated.    Cambridge, 
but    in    the    young    it    is    far 

from  clear  that  this  is  the  case.  However  that  may  be,  they 
seem  to  convey  air  to  the  true  breathing  organs,  situate  inside 
the  cleft  on  the  apical  part  of  the  abdomen  itself;  but  details 
as  to  the  way  in  which  transfer  of  air  is  effeeted  along  this 
1  Ferrari,  Monograph  of  Nepa,  Ann.  J/"fi,ni.-<.  ///.//.  iii.  1888,  p.  171. 


564 


HEMIPTERA-HETEROPTERA 


CHAP. 


very  protracted  passage  are  not  forthcoming.  The  develop- 
ment in  Nc'pa,  has  been  studied  to  a  certain  extent.  The 
apical  stigmata  are  the  only  pair  of  the  abdominal  stigmata 
that  exist  in  the  imago  of  Nepa,  the  other  six  pairs  being 
obliterated  ;  the  third,  fourth,  and  fifth,  according  to  .Schiodte,  in 
a  very  peculiar  manner :  hence,  as  Martin  says,1  the  respiratory 
system  is  metapneustic.  In  an  earlier  stage  of  the  life,  however, 
these  six  pairs  of  stigmata  exist  in  functional  activity  placed  in 
a  groove  on  the  under  surface  of  the  body ;  so  that  the  condition 
is  that  termed  peripneustic,  and  remains  so  till  the  final  moult, 
when  the  long  siphon  appears.  In  the  early  life  there  is  a 
short  prolongation  from  the  end  of  the  body  in  connection  with 
the  pair  of  grooves  alluded  to,  but  it  is  a  single  unpaired  organ, 
and  does  little  therefore  to  explain  the  appear- 
ance of  the  siphon,  which  must,  at  present,  be 
considered  as  being  suddenly  developed  at  the 
last  moult. 

The  eggs  of  Xepidae  are  remarkable  objects ; 
that  of  the  common  water-scorpion   bears   seven 
filaments  at  one  end  (Fig.   277);  while  that  of 
1!« nut m  is  more  elongate,  and  bears  only  twTo, 
very  elongate,  threads.      These  eggs  are  deposited 
in  the   stems   of  water-plants,  being  introduced 
therein,  so  that  the  body  of  the  egg  is  concealed 
while  the  threads  project :   those  of  Hanatra  are 
placed  in   stems  floating   on   the   water,  and  in 
consequence  of  the  threads  the  stems  look  as   if 
they  were  infested  by  some  fungus.      The  struc- 
FIG.   277.  —  Egg    of  ture    and    formation    of    the    eggs    have    been 
(After  KorscliVit')   investigated  with    considerable   detail    by   Kor- 
schelt.L'      He  looks   on    the    filaments    as  pneu- 
matic, and  considers   that  they  supply  a  coating  of  air   to   the 
body  of  the  egg ;  they  consist  of  a  spongy  mass  encircled  by  two 
layers  of  egg-shell,  both   of  these  latter  being  peculiar  in  struc- 
ture ;  the  spongy  mass  is   continuous   with  a  layer  of  the  same 
kind  of  substance  placed  on  the  interior  of  the  shell  of  the  body 

1  //////.  S<>r.  PlrHiuiiiit.  (8)  v.  1893,  ]>.  :"7.  There  is  sonic  diversity  of  opinion 
as  bo  the  ivspiratory  orilices,  and  some  authorities  say  that  thoracic  stigmata  exist 
even  in  I  In-  inin^'i. 

-  Ad, i  Ac.  German,  li.  1887,  p.  224,  and  Zeilschr.  wiss.  Zoot.  xliii.  1886,  p.  537. 


vin  NEPIDAE NAUCORIDAE — BELOSTOMIDAE  565 

of  the  egg.  It  will  be  recollected  that  we  have  described  (p. 
562)  an  egg,  apparently  of  the  same  nature,  deposited  by  Capsids 
in  the  stems  of  land  plants,  so  that  it  is  very  doubtful  whether 
the  threads  are  really  connected  with  the  aquatic  development 
of  the  embryo  in  Nepidae.  But  the  most  interesting  feature 
connected  with  these  eggs  is,  according  to  Korschelt,  the  mode  of 
development  of  the  filaments,  which  is  sui  generis  ;  the  shell  of 
the  egg  is  developed  in  the  ordinary  manner  as  an  exudation  or 
excretion  from  epithelial  cells;  but  the  shell  of  the  filament  is 
formed  as  an  intracellular  product ;  a  mode  of  chitin-formation 
that  appears  to  be  peculiar  to  this  structure.  Korschelt  remarks 
that  "  it  is  in  the  highest  degree  worthy  of  attention  how  by 
any  process  of  development  through  a  large  number  of  success!  \e 
generations  so  complex  a  condition  could  be  established  as  the 
result  of  adaptation  to  external  conditions ;  and  this  becomes 
even  more  interesting  when  we  remember  that  highly  peculiar 
special  processes  and  departures  from  the  usual  modes  of  tissue- 
formation  are  necessary  to  permit  the  development  of  this 
apparatus." 

Fam.  22.  Naucoridae. — No  ocelli,  and  no  terminal  process 
to  the  body;  front  legs  inserted  on  or  near  the  front  of  tin' 
prosternum.  Anterior  femora  usually  broad  and  flat. — The 
members  of  this  family  are  truly  aquatic,  and  swim  readily  in 
the  water.  The  family  is  small,  including  about  nine  gen  em 
and  thirty  species,  but,  like  many  water-Insects,  the  genera  .'in- 
widely  distributed.  We  have  two  in  Britain — one  of  them, 
Naucoris,  common ;  the  other,  Aplielocheirus,  rare. 

Fam.  23.  Belostomidae. — No  ocelli,  and  no  long  terminal 
tin'  /mi///  ;  front  legs  inserted  near  the  front  of  the  pro- 
J'tix/i'i'/ii/1  tibiae  not  spiny  ;  flattened  and  provided  u-i Hi 
swimming  hairs. — Although  these  Insects  have  been  classified 
with  Nepidae  they  have  but  little  relation  therewith  ;  on  the 
other  hand,  the  distinctions  from  Naucoridae  are  far  less  im- 
portant. The  family  includes  some  of  the  largest  Insects.  The 
South  American  Belostoma  grande  attains  a  length  of  four  or  four 
and  a  half  inches.  Notwithstanding  their  considerable  size 
Belostomidae  exist  in  very  large  numbers  in  some  loealilies,  and 
frequently  destroy  young  fish  by  aid  of  the  powerful  though 

1    Ktirsclielt,  Ada.  t.c.  p.  245.     Compare  the  remarks  we  have  made  on  p.  559  as 
to  the  peculiarities  of  eggs  of  many  other  Hemiptera. 


566 


HEMIPTERA-HETEROPTERA 


CHAP. 


short  rostrum.  They  appear  to  be  unable  to  resist  the  attrac- 
tion of  artificial  light,  and  are  consequently  sometimes  destroyed 
in  large  numbers.  It  has  long  been  known  that  species  of  the 

genera  Diplonychus  and  Zaitha  carry 
their  eggs  on  their  backs.  There  is  no 
special  receptacle  for  the  purpose,  but  the 
eggs  are  kept  in  their  peculiar  position 
by  means  of  a  cement  insoluble  in  water. 
It  has  been  stated  by  Dimmock  that 
they  are  placed  in  position  by  means  of 
a  long,  flexible  ovipositor.  Schmidt,  how- 
ever, found  that  a  specimen  of  Diplo- 
nychus, bearing  eggs  and  examined  by 
him,  was  a  male,  and  he  subsequently 
found  that  this  was  the  case  with  other 
FIG.  278.  —  Zaitha  anura,  egg-bearing  individuals  of  other  species, 

carrying  eggs  on  its  back.    go  that    the    mode    jn    which    the    eggs    are 
West  Indies.  _  _  _  oi;> 

placed  in   this  position  and  the  object  of 

so  curious  a  habit,  remain  uncertain.  The  species  of  Bclostoma 
are  highly  remarkable  on  account  of  the  curious  and  complex 
structure  of  their  antennae,  in  respect  of  which  the  nearest 
analogy  is  to  be  found  in  the  large  Coleoptera  of  the  genus 
Hydrophilus.  A  very  deep,  ear-like  pocket,  exactly  suited 
to  the  form  of  the  antennae, 
exists  on  the  under  side  of  the 
head ;  hence  in  repose  no  sign 
of  the  peculiar  shape  of  the 
antennae  exists.  When  the 
antennae  are  placed  in  this  ear-  ,« 
like  pocket  only  the  one  side 
of  the  basal  joints  is  exposed, 
the  long  processes  being  re-  A 

i     •  4.1          3  i  Fir:.    279. — Antenna    of   l><'l<>xt<iin«    sp.     A. 

Ceived    lllto     the     deep     pocket.          bne  side  of  the  under  surface  of  the  head! 

with  antenna,  />,  extended  ;  B,  with  the 
antenna  retracted,  a,  Side  of  head  ;  c, 
pocket  for  antenna  ;  rf,  position  of  the  eyes. 
The  corresponding  joints  of  the  antenna 
are  numbered  1,  2,  3,  4  in  each  figure. 


In  HydropJiihis  the  antenna  is 
used  as  an  accessory  organ  of 
respiration,  and  it  will  be  in- 
teresting to  learn  whether  this 
is  also  the  case  in  Bdostoma.  Belostomidae  have  patches  of  air- 
carrying  pubescence,  analogous  with  those  of  HydropJiilus,  on 
the  under  sides  of  the  body,  elytra  and  wings,  but  we  do  not 


viii  BELOSTOMIDAE — NOTONECTIDAE CORIXIDAE          567 

know  how  they  are  charged.  Another  extremely  interesting 
analogy  is  found  in  the  manner  in  which  the  elytra  are  locked 
to  the  body ;  a  projection  from  the  thoracic  side-pieces,  forming 
a  long  pouch,  into  which  a  fold  on  the  inner  side  of  the  elytra 
fits,  the  two  being  subsequently  locked  by  the  action  of  some 
special  projections.  This  arrangement  is  similar  to  that  which 
exists  in  the  anomalous  family  of  water-beetles  Pelobiidae.  In 
order  to  make  this  mechanism  more  perfect  the  side-pieces  in 
Belostoma  form  free  processes.  Martin  has  informed  us  that  the 
young  have  the  metasternal  episternum  prolonged  to  form  a 
lamella  that  he  thinks  may  be  for  respiratory  purposes.1  About 
twelve  genera  and  upwards  of  fifty  species  of  Belostomidae  are 
known.  None  exist  in  our  isles,  but  several  species  extend  their 
range  to  Southern  Europe.  In  the  waters  of  the  warm  regions  of 
the  continents  of  both  the  Old  and  New  Worlds  they  are  common 
Insects,  but  as  yet  they  have  not  been  found  in  Australia. 

Fam.  24.  Notonectidae. — Prosternum  short,  so  that  the  legs 
are  placed  near  the  lack  part  of  it  as  well  as  near  the  front ;  ~back 
of  the  head  overlapped  by  the  front  of  the  pronotum. — The  water- 
In  (utmeii  are  extremely  common  in  our  ponds,  where  they  may 
be  seen  rising  to  the  surface  and  raising  the  posterior  extremity 
of  the  body  for  breathing.  They  swim  on  their  backs  instead  of 
in  the  usual  position,  and  have  an  elaborate  arrangement  of  long 
hairs  on  the  body  to  assist  them  to  carry  about  an  air-supply. 
They  are  said  to  be  lighter  than  the  water,  and  to  have  some 
difficulty  in  keeping  away  from  the  surface.  Notonecta  glauca 
is  the  only  British  species,  but  we  have  a  second  minute  Insect, 
Plea  minutissima,  belonging  to  the  family.  It  lies  in  the  mud  at 
the  bottom  of  shallow  waters,  and  may  sometimes  be  fished  up  in 
great  numbers.  It  is  considered  by  some  authors  to  form  a 
distinct  family.  The  oviposition  of  Notonecta  has  been  observed 
by  Regimbart ;  the  eggs  are  inserted  into  the  stems  of  aquatic 
plants. 

Fam.  25.  Corixidae. — Prosternum  short,  as  in  Notonectidae; 
xn  i a  i a  if,  of  the  head  free  from  the  thorax. — We  have  numerous 
species  of  the  genus  Corixa  in  Britain  ;  and  others  extremely 
similar  in  appearance  occur  in  various  parts  of  the  world.  The 
head  is  remarkably  free,  and  capable  of  great  rotation.  On 
dissection  it  is  found  to  be  attached  to  the  thorax  only  by  a 

1  Bull.  Mus.  Paris,  1896,  p.  238. 


568  HEMIPTERA  CHAP. 


narrow  area ;  in  this  respect  it  differs  widely  from  Notonecta, 
which  possesses  an  extremely  large  occipital  foramen,  and  the 
head  of  which  possesses  bub  little  freedom  of  movement.  The 
extremely  short  proboscis  is  more  or  less  retractile,  and  therefore 
frequently  appears  absent.  A  second  British  genus  consists  of  a 
single  species,  Sigara  minutissima.  These  Insects,  unlike  Noto- 
nccta,  are  quite  at  home  beneath  the  water,  where  they  scurry 
about  with  extreme  rapidity,  and  occur  sometimes  in  enormous 
numbers.  In  Mexico  the  eggs  of  Corixa  americana  and  of  C. 

C3O 

fe/iwrata  are  used  as  food,  and  are  said  to  be  very  nice.  The 
Insects  themselves  are  used  as  food  in  both  Mexico  and  Egypt. 
The  species  of  this  family  can  make  a  noise  beneath  the  water  by 
rubbing  the  front  feet  against  the  proboscis.1  The  males  have  a 
very  complex  asymmetry  of  the  terminal  segments,  and  in  some 
species  possess  on  one  side  of  the  dorsal  surface  a  curious  asym- 
metrical organ  consisting  of  rows  of  very  closely-packed,  in- 
tensely black,  comb-like  plates,  called  by  Buchanan  White  a 
strigil.  This  organ  seems  to  be  similar  to  the  peculiar  structures 
found  on  the  terminal  segments  of  certain  species  of  Scutellerides. 

Sub-Order  II.   HOMOPTERA.- 

Fam.  1.  Cicadidae. — Head  with  three  ocelli,  placed  triangularly 
on  the  summit  betu'ccn  the  compound  eyes ;  antennae  consisting 
of  a  short  basal  joint,  surmounted  by  a  hair-like  process  divided  into 
about  Jive  segments.  Front  femora  more  or  less  thick,  armed  with 
teeth.  Peduncle  (or  basal  joints)  of  antennae  without  sensitive 
organs. — This  important  family  consists  chiefly  of  large  Insects, 
few  being  as  small  as  one  inch  across  the  expanded  wings,  while 
in  some  the  expanse  is  as  much  as  seven  inches.  As  a  rule 
the  four  wings  are  transparent  and  shining,  with  the  nervures 
remarkably  distinct  and  dark  coloured  :  but  there  are  numerous 
forms  where  the  whole  creature,  including  the  wings,  is  highly 
pigmented  in  a  showy  manner ;  frequently  in  black  and  yellow. 
Cicadas  are  said  to  be  without  any  special  protection,  and  to  be 
destroyed  in  considerable  numbers  by  birds  and  other  animals. 
The  body  is  broad  and  robust,  and  is  never  shaped  into  the 
extravagant  forms  we  meet  with  in  some  of  the  other  families  of 
Homoptera.  Cicadidae  are  almost  confined  to  the  warmer  regions 

1  See  Carpenter,  Irish  Naturalist,  iv.  1895,  p.  59. 
2  See  remarks  on  pp.  543,  544. 


VIII 


HOMOPTERA CICADIDAE 


569 


of  the  earth,  but  we  have  one  species,  a  great  rarity,  iu  the  ex- 
treme south  of  England;  altogether  there  are  about  800  species 
known.  These  Insects  are  seen  above  ground — so  far  as  the 
life-histories  are  at  present  known — only  in  the  perfect  condi- 
tion, the  creatures  in  their  earlier  stages  being  subterranean  and 
living  on  roots.  As  soon  as  the  individual  comes  out  of  the 
ground  it  splits  open  the  nymph-skin,  and  the  perfect  Cicada 
emerges.  One  species — the  North  American  Cicada  septendecim 
—is  a  most  notorious  Insect  owing  to  its  life-cycle  of  seventeen 


B 


FIG.  280.  —  Cicada  septendecim.  North  America.  (After  Riley. )  A,  Larva;  B, 
iiyniph  ;  C,  nymph  skin  after  emergence  of  the  imago,  D ;  E,  section  of  twig  \vitli 
series  of  eggs  ;  F,  two  eggs  magnified. 

years.  It  is  considered  that  the  individual,  after  nearly  seven- 
teen years  of  underground  existence,  comes  to  the  surface  and 
lives  for  a  brief  period  the  life  of  a  noisy  Insect.  This  is  the 
only  Insect  at  present  known  having  so  considerable  a  longevity. 
This  fact,  and  several  other  peculiarities,  have  attracted  much 
attention,  so  that  there  is  an  extensive  literature  connected  with 
the  seventeen-year  Cicada.  It  has  a  wide  distribution  over  the 
United  States,  but  does  not  confine  its  appearance  to  every 
seventeenth  year,  being  found  somewhere  or  other — frequently 
in  numerous  localities — almost  every  year.  The  evidence  as  to 
its  periodicity  has  been  obtained  by  taking  the  locality  and  other 
points  into  consideration  as  well  as  the  year  of  appearance. 


5/0  HEMIPTERA-HOMOPTERA  CHAP. 

By  so  doing  it  has  been  found  possible  to  establish  the  existence 
of  twenty-two  broods  which  are  distinguished  by  consecutive 
numeration.  This  being  done,  the  evidence  as  to  the  years 
during  which  Cicadas  have  appeared  in  any  given  locality  is 
examined,  and  the  result  is  believed  to  bear  out  the  view  that  the 
life-cycle  of  the  individual  Insect  is  really  one  of  seventeen  years. 
According  to  this  view  there  are,  underground,  in  certain  localities 
individuals  of  different  ages  that  will  appear  on  the  surface  as 
mature  individuals  in  different  years.  Thus  in  1885  it  was 
iinderstood  that  there  were  underground  in  Alabama  two  broods, 
viz.  brood  xviii.  that  would  appear  on  the  surface  in  1894,  and 
brood  iv.  that  would  appear  on  the  surface  in  1896.  The  pre- 
dictions made  as  to  the  years  in  which  Cicadas  would  appear  in 
some  given  locality  are  considered  to  have  proved  correct.  More- 
ever,  particular  entomologists  have  in  certain  localities  verified 
by  personal  examination  the  appearance  of  the  Insects  for  several 
consecutive  periods  of  seventeen  years.  These  facts  appear  fairly 
conclusive,  but  they  are  much  complicated  by  another  point,  viz. 
that  in  certain  localities  the  period  is  one  of  thirteen,  not  of 
seventeen,  years.  This  is  to  some  extent  a  question  of  climate, 
the  thirteen-year  interval  being  chiefly  characteristic  of  the 
Southern  States.  It  is  not,  however,  entirely  so,  for  there 
are  localities  in  which  the  broods  have  an  interval  of  either 
thirteen  years  or  seventeen  yenrs.  Another  fact  should  be 
remembered,  viz.  that  it  is  admitted  that  not  quite  all  the 
individuals  of  a  particular  brood  are  true  to  their  proper  time  of 
appearance ;  in  other  words,  a  few  specimens  may  appear  pre- 
cociously a  year  or  two  before  their  comrades,  while  some  may 
lag  behind  to  a  considerable  extent.  It  is  therefore  a  matter 
for  great  surprise  that,  under  these  circumstances,  the  broods 
should  keep  distinct  at  all,  for  one  would  suppose  that  time- 
variation  of  this  kind  would  lead  to  completely  obscuring  the 
distinctness  of  the  broods.  We  must  also  call  attention  to  the 
fact  that  both  the  seventeen-year  and  the  thirteen-year  broods 
have  a  dimorphic  form,  or  sub-species,  called  C.  cassinii  which 
accompanies  the  ordinary  form,  with  which  it  is  apparently  as  a 
rule  not  connected  by  intermediates.1 

\\V  must  nTrr  those  who  may  wish  for  further  information  as  to  this  complex 
ami  ilifliciilt  question  to  the  writings  of  the  late  Professor  Riley,  especially  to 
! In  Hi  t  in  Xo.  8,  1885,  U.S.  Department  of  Agriculture,  division  of  entomology  ; 
.•UK!  to  the  more  recenl  n-port  l>v  M.ulatt,  Hull.  Dcp.  Ayric.  Ent.,  N.S.  No.  1-1,  1S9S. 


vni  CICADIDAE  571 

Cicadidae  are  provided  with  powerful  ovipositors.  The  eggs 
of  C.  septendecim  are  deposited  in  the  woody  stems  of  bushes; 
after  remaining  there  a  few  weeks  the  young  hatch  out,  drop 
to  the  ground,  and,  as  previously  stated,  disappear  for  nearly 
seventeen  years,  nearly  the  whole  of  which  time  is  passed 
in  the  larval  state,  the  nymph -condition  existing  for  only 
a  few  days.  They  feed  on  the  roots  of  various  trees ;  it  has 
been  said  that  they  are  injurious  in  this  way,  but  other 
authorities  maintain  that  they  suck  only  a  moist  exudation 
from  the  roots.  It  is  very  difficult  to  obtain  information  as  to 
their  strange,  prolonged,  subterranean  life  ;  it  said  that  the  Insects 
sometimes  penetrate  to  a  great  depth — ten  feet,  even  twenty  feet 
are  mentioned ; — and  as  great  changes  may  take  place  on  the  surface 
during  their  long  lives,  these  Insect  Kip  Van  Winkles  some- 
times emerge  in  very  strange  conditions,  and  may  appear  even  in 
deep  cellars.  When  the  pupa  comes  to  the  surface  it  hooks 
itself  on  to  the  stem  of  some  plant  or  other  object,  the  skin  of 
the  back  splits,  and  the  Cicada  emerges.  Among  the  inexplicable 
peculiarities  of  this  Insect  must  be  mentioned  the  fact  that  when 
emerging  it  sometimes  constructs  chimneys,  or  flues,  extending 
several  inches  above  the  surface  of  the  ground.  The  reason  for 
this  is  much  disputed ;  it  was  said  that  they  are  for  refuge 
against  inundations,  but  this  appears  to  be  very  doubtful.  Certain 
of  the  broods  consist  of  an  almost  incalculable  number  of  indi- 
viduals, and  it  is  very  strange  to  hear  woods,  or  other  localities, 
that  have  been  for  many  years  free  from  these  Insects,  all  at 
once  resounding  with  their  noisy  song.  The  seventeen-year 
Cicada  is  considered  to  be  doomed  to  a  speedy  extinction ;  the 
extension  of  cultivation  and  building,  and  the  introduction  to 
America  of  the  English  sparrow,  are  likely  to  prove  too  much 
for  the  Insect. 

Although  Hemiptera  are  classified  by  many  among  the 
Ametabola  or  Insects  without  metamorphosis,  it  is  impossible 
to  deny  that  the  Cicadidae  exhibit  a  considerable  amount  of 
metamorphosis,  and  they  are  usually  mentioned  as  exceptional. 
The  young  (Fig.  280,  A)  is  totally  unlike  the  adult  in  form 
and  colour,  and  maintains,  to  a  certain  extent,  its  existence 
by  the  aid  of  a  different  set  of  implements.  The  larva.  <>f  tin- 
Cicada  is  colourless,  with  an  integument  of  verv  feeble  consistence, 
rather  large  antennae,  and  a  remarkable  pair  <>f  fossorial  legs; 


572  HEMIPTERA-HOMOPTERA  CHAP. 

the  wings  are  totally  wanting.  The  mode  of  passage  from  the 
larval  to  the  pupal  state  has  not  been  recorded.  The  pupa,  or  nymph, 
differs  from  the  larva  by  its  much  shorter,  compressed  form  ;  by 
being  encased  in  a  remarkably  hard  shell  ;  and  by  the  antennae 
approximating  in  form  to  those  of  the  adult.  It  has  short  wing- 
pads  at  the  sides  of  the  body  ;  the  front  legs  are  remarkably 
powerful,  and  the  creature  is  capable  of  moving  about  ;  the  imago 
escapes  from  the  pupa  by  the  splitting  dorsal  ly  of  the  middle  of 
the  thoracic  segments.  The  empty  pupa-skin  does  not  shrivel, 
but  retains  its  form,  and  in  countries  where  Cicadas  occur,  fre- 
quently attracts  attention  by  the  strange  form  it  presents,  being 
often  placed  in  a  conspicuous  position. 

Song.  —  Cicadas  are  the  most  noisy  of  the  Insect  world:  the 
shrilling  of  grasshoppers  and  even  of  crickets  being  insignificant 
in  comparison  with  the  voice  of  Cicada.  Darwin  heard  them 
in  South  America  when  the  Bcuyle  was  anchored  a  quarter 
of  a  mile  from  the  shore  ;  and  Tympanoterpes  //'//"*,  from  the 
same  region,  is  said  to  make  a  noise  equal  to  the  whistle  of  a 
locomotive.1  A  curious  difference  of  opinion  prevails  as  to 
whether  their  song  is  agreeable  or  not  ;  in  some  countries  they 
are  kept  in  cages,  while  in  others  they  are  considered  a  nuisance. 
The  Greeks  are  said  to  have  decided  in  favour  of  their  per- 
formances, the  Latins  against  them.  Only  the  males  sing,  the 
females  being  completely  dumb  ;  this  has  given  rise  to  a  saying 
by  a  Greek  poet  (so  often  repeated  that  it  bids  fair  to  become 
immortal)  '•'  Happy  the  Cicadas'  lives,  for  they  all  have  voice- 
less wives."  The  writer  considers  the  songs  of  the  European 
species  he  has  heard  far  from  unpleasant,  but  he  is  an  entomologist, 
and  therefore  favourably  prepossessed  ;  and  he  admits  that 
Biley's  description  of  the  performances  of  the  seventeen-year 
Cicada  is  far  from  a  satisfactory  testimonial  to  the  good  taste  of 
that  Insect  ;  Kiley  says,  "  The  general  noise,  on  approaching  the 
infested  woods,  is  a  combination  of  that  of  a  distant  threshing- 
machine  and  a  distant  frog-pond.  That  which  they  make  when 
disturbed,  mimics  a  nest  of  young  snakes  or  young  birds  under 
similar  circumstances  —  a  sort  of  scream.  They  can  also  produce 


entomologists  consider  that  this  "railway-whistle"  note  is  the  result 
of  flic  combined  efforts  of  several  individuals.  Of.  lUatlicw,  Ent.  May.  xi.  1875, 
1>.  17.r>. 

-  Il  is  unnecessary  !<>  s;iy  tlmt  the  poet  was  not  Sappho,  but  one  of  the  baser  sex, 

mined    XciKircliiis. 


vin  CICADIDAE  573 

a  chirp  somewhat  like  that  of  a  cricket  and  a  very  loud,  shrill 
screech  prolonged  for  fifteen  or  twenty  seconds,  and  gradually 
increasing  in  force  and  then  decreasing."  The  object,  or  use  of 
the  noise  is  very  doubtful ;  it  is  said  that  it  attracts  the 
females  to  the  males.  "  De  gustibus  11011  est  disputandum  !  "  per- 
haps, however,  there  may  be  some  tender  notes  that  we  fail  to 
perceive ;  and  it  may  be  that  the  absence  of  any  definite  organs 
of  hearing  reduces  the  result  of  a  steam-engine  whistle  to  the 
equivalent  of  an  agreeable  whisper.  'No  special  auditory  organs 
have  been  detected  :  as  we  have  already  intimated ;  and  certain 
naturalists,  amongst  whom  we  may  mention  Giard,  think  that 
the  Insects  do  not  hear  in  our  sense  of  the  word,  but  feel 
rhythmical  vibrations  ;  it  is  also  recorded  that  though  very  shy 
the  Insects  may  be  induced  to  approach  any  one  who  will  stand 
still  and  clap  Ids  hands — in  good  measure — within  the  range  of 
their  sensibilities.  There  is  a  good  deal  of  support  to  the  idea 
that  the  males  sing  in  rivalry. 

Vocal  structures. — Although  we  may  not  be  able  to  pro- 
nounce a  final  opinion  as  to  the  value  to  the  Insect  of  the  sounds, 
yet  we  cannot  withhold  our  admiration  from  the  structures  from 
which  they  proceed.  These  are  indeed  so  complex  that  they 
must  be  ranked  as  amongst  the  most  remarkable  voice-organs  in 
the  animal  kingdom.  They  are  totally  different  from  the 
stridulating  organs  that  are  found  in  many  other  Insects,  and  are 
indeed  quite  peculiar  to  the  Cicadidae.  Some  difference  of 
opinion  has  existed  as  to  the  manner  in  which  the  structures 
act,  but  the  account  given  by  Carlet,  some  of  whose  figures  we 
reproduce,  will,  we  believe,  be  found  to  be  essentially  correct.  The 
struct  HITS  are  partly  thoracic  and  partly  abdominal.  On  ex- 
amining a  male  Cicada  there  will  be  seen  on  the  under  surfaces 
two  plates — the  opercula — usually  meeting  in  the  middle  line  of 
the  body  and  overlapping  the  base  of  the  abdomen  to  a  greater 
or  less  extent  according  to  the  species,  sometimes  nearly  covering 
this  part  of  the  body;  these  are  enlargements  of  the  rnetatlioracic 
epimera  ;  they  can  be  slightly  moved  away  from  the  abdomen, 
and,  as  the  latter  part  is  capable  of  a  still  greater  extent  of 
movement;  a  wide  fissure  maybe  produced, displaying  the  complex 

1  S\\  inimi  claims  that  one  of  the  membranes  in  the  vocal  apparatus  is  an  auditory 
oi'L,faii  ;  if  so,  tlic  male  \\ould  !><•  deafened  by  hU  u\vu  uoi.-c,  while  the  females,  not 
possessing  the  origan,  should  not  hear  tin-  -<nig. 


574 


HEMIPTERA-HOMOPTERA 


CHAP. 


structures.  In  order  to  see  the  parts  it  is  better  to  cut  away 
an  operculum  ;  underneath  it  three  membranes  can  be  seen,  an 
external,  the  timbal ;  an  anterior,  the  folded  or  soft  membrane ; 
and  a  posterior,  the  mirror.  This  last  is  a  most  beautiful  object, 
tensely  stretched  and  pellucid,  yet  reflecting  light  so  as  to  be 
of  varied  colours ;  there  are  also  three  stigmata,  and  some 
chambers  connected  with  the  apparatus.  The  sound  is  primarily 
produced  by  the  vibrations  of  the  timbal,  to  which  a  muscle  is 
attached  ;  the  other  membranes  are  probably  also  thrown  into  a 
condition  of  vibration,  and  the  whole  skeleton  of  the  Insect  helps 
to  increase  or  modify  the  sound,  which  is  probably  also  influenced 


Mcs 


v-~m 


t.a, 


B 


FIG.  281. — Musical  apparatus  of  Cicada plebeia.  (After  Carlet.)  A,  Ventral  view  (Oper- 
culum on  right  side  is  removed)  ;  aj>,  apophysis  ;  c,  cavern  ;  c,  trochantin  (cheville 
of  Reaumur)  ;  ent,  part  of  internal  skeleton  of  abdomen  ;  mi,  specular  membrane  ; 
m.pl,  soft  or  folded  membrane  ;  p,  base  of  leg ;  st,  st',  st",  stigmata  ;  t,  drum 
"timbale"  ;  v,  operculum  ;  la,  first,  2a,  second  abdominal  segment :  B,  same  seen 
laterally,  portion  of  abdominal  wall  as  well  as  operculum  removed  ;  A,  point  of 
insertion  of  hind  wing  ;  J/es,  mesothorax  ;  ac,  scutum  of  metathorax  ;  3«,  third 
abdominal  segment  ;  rest  as  in  A. 

by  the  position  of  the  opercula.  The  stigmata  probably  play  an 
important  part  by  regulating  the  tension  of  the  air  in  the 
chambers.  In  the  female  some  of  the  structures  are  present  in 
a  rudimentary  form,  but  there  are  no  muscles,  and  this  sex 
appears  to  be  really  quite  voiceless. 

Fam.  2.  Fulgoridae. — Ocelli  two  (rarely  three,  or  entirely 
obsolete),  placed  In'iiciith  ///<•  <>i/rs  or  '//car  the  eyes,  'usually  in 
cavities  of  the  cheeks,  antennae  ji/<irr<l  Irtieafh  the  eyes,  very  variable 
in  form  ;  i/xi/u/li/  of  //ro  joints  trriiii  intli'il  !>//  it  re ri/  fine  hair, 
I  In'  second  joint  •//•/'///  o  iH-cul'mr  /V,<7///v  of  the  surf  ace,  owing  to  the 
existence  of  ,sr//,s////r  structures  (Hansen).  Form  of  head  very 
diverse  ;  vertex  and  face  forming  either  a  continuous  curve,  or  the 
of  tin'  vertex  //  m!  fm-c  formi/i//  nn  acute  angle,  or  loth  pro- 


VIII 


FULGORIDAE 


575 


longed  so  as  to  form  a  projection  or  growth  that  may  lie  monstrous. 
Prothorax  neither  armed  nor  unusually  developed. 

This  family  is  of  large  extent,  and  includes  at  present  so  great 
a  variety  of  forms  that  it  is  really  almost  impossible  to  frame  a 
definition  that  will  apply  to  all.  The  unusual  situation  of  the 
ocelli  and  the  peculiar  second  joint  of  the  antennae  must  at 
present  be  taken  as  the  best  diagnostic  characters :  occasionally  a 
third  ocellus  is  present.  Some  of  the  Fulgoridae  are  amongst  the 
largest  Insects,  others  are  quite  small.  The  family  includes  tl it- 
so-called  Lantern-flies,  in  which  the  front  of  the  head  forms  a  huge 
misshapen  proboscis  that  was  formerly  believed  to  be  luminous. 


FIG.  282. — Ftilgora  canddaria.      x  1.     China. 

Many  of  the  species  are  of  brilliant  or  beautiful  coloration.  A 
great  many — and  of  very  different  kinds — have  the  curious  power 
of  excreting  large  quantities  of  a  white,  flocculent  wax.  This  is 
exhibited  by  our  little  British  Insects  of  the  genus  Cixius,  and  in 
some  of  the  exotic  forms  is  carried  to  an  extent  that  becomes  a, 
biological  puzzle.  The  Tropical  American  genus  Phenax  may  be 
cited  as  an  example ;  being  about  an  inch  long  it  flies  about  with 
a  large  mass  of  this  waxy  substance  twice  as  long  as  itself; 
indeed,  in  the  Mexican  P.  auricoma,  the  waxy  processes  are  four 
or  five  inches  long.  This  wax  forms  a  favourite  food  of  cert ;i in 
kinds  of  Lepidoptera,  and  two  or  three  larvae  of  a  maggot-like 
nature  may  frequently  be  found  concealed  in  the  wax  of  the  live. 
Fulgorids  ;  this  has  been  recorded  by  "VVestwood  as  occurring 
in  India;  and  Champion  has  observed  it  in  the  Xe\v  AYorld.1 

1  P.  ent.  tioc.  London,  1883,  ]>.  20. 


5/6 


HEMIPTERA-HOMOPTERA 


CHAP. 


The  wax  of  Fulgorids  is  used  by  the  Chinese  for  candles  and 
other  purposes ;  and  this  white  Insect-wax  is  said  to  be  much 
esteemed  in  India.  Very  curious  chemical  substances  have  been 
obtained  from  it,  but  its  importance  in  the  economy  of  the 
Insects  that  produce  it  is  quite  obscure.  We  have  about  seventy 
species  of  Fulgoridae  in  Britain.  They  belong  to  the  sub-families 
Tettigometrides,  Issides,  Cixiides,  and  Delphacides,  which  by 
many  authors  are  treated  as  separate  families.  The  exotic  sub- 
family Flatides  is  highly  peculiar.  In  some  of  its  members  the 
head  is  very  different  from  that  of  the  ordinary  forms,  being 
narrow,  and  the  vertex  and  front  forming  a  continuous  curve. 
Some  of  these  Insects  are  remarkably  like  butterflies  or  moths 
(c.y.  the  African  Ityr<u-n,  nigrocincta  and  the  species  of  the  genus 
Pocli<r:i<i\  but  the  young  are  totally  unlike  the  old,  the  posterior 
part  of  the  body  bearing  a  large  bush  of  curled,  waxy  projections, 
several  times  the  size  of  the  rest  of  the  body. 

Fam.  3.  Membracidae. — Protliorax  prolonged  backwards  into 
a  Jiooil  or  -jH-iH'r.ws  of  diverse  forms  ;  antennae  inserted  in  front  of 
the  eyes ;  ocelli  two, placed  between  the  two  eye*. — This  family  is  of 


FIG.  2S3. — A,  B,  Hcteronotii.s  trinodosus.  A,  Male  seen  from  above;  B,  profile  of 
female  ;  <»,  terminal  part  of  pronotum  ;  1>,  terminal  part  of  abdomen  :  C,  front 
view  of  head  and  pronotum  of  <  '///</'"/"'</  i-fiim/it.  Both  species  from  Central 
America.  (From  Biul.  C'entr.  Amer.  Rhynch.  llnun^it.  II.) 


l;n;jy  extent  but  its  members  are  chiefly  tropical,  and  are  specially 
abundant  in  America.  Although  not  of  large  size  the  Membracidae 
are  unsurpassed  for  the  variety  and  grotesqueness  of  their  shapes, 
due  to  the  unusual  development  of  the  pronotum.  We  figure  two 
of  these  forms  (Fig.  283).1  Very  little  is  known  about  their 

1  A  (-(insidcralilc  variety  of  these  extraordinary  creatures  are  figured  in  Biol. 
Centr.  A  HUT.  HI*  inn-//.  Ilmiwpt.  ii. 


vin  MEMBRACIDAE CERCOPIDAE  577 

habits  and  life-histories.  We  have  only  two  species  of  the  family 
in  Britain,  and  these  do  not  afford  any  ground  for  supposing  that 
there  are  any  peculiarities  in  their  lives  at  all  commensurate 
with  the  oddness  of  the  Insect's  structures.  Belt  has  recorded 
the  fact  that  in  Nicaragua  the  larvae  of  certain  Homoptera  were 
assiduously  attended  by  ants  for  the  sake  of  a  sweet  juice 
excreted  by  the  bugs,  but  it  is  by  no  means  clear  that  these  larvae 
were  really  those  of  Membracidae.  In  North  America  Ceresa 
Iitt/xift/s  and  C.  t«ui'iiiit  place  their  eggs  in  an  extremely  m-,it 
manner  in  the  woody  twigs  of  trees.  The  young  have  but  little 
resemblance  to  the  adults,  the  great  thoracic  hood  being  absent, 
while  on  the  back  there  is  on  each  segment  a  pair  of  long,  sub- 
erect  processes  having  fringed,  or  minutely  spiny,  margins.1 

Fam.  4.  Cercopidae. — Ocelli  two  (occasionally  absent ,  /i/<t<;></ 
oil  the  vertex;  antennae  placed  between  the  eyes.  Tln>r«.i-  m>t 
j  >, •<•/// /'<>,•///  formed. — In  the  characteristic  forms  of  this  family 
the  front  of  the  vertex  bears  a  suture,  touched  on  each  side 
by  one  at  right  angles  to  it,  or  converging  to  it  so  as  to  form  a 
triangle  or  a  sort  of  embrasure  ;  the  hind  tibiae  have  only  one  to 
three  strong  spines.  The  Cercopidae  are  much  less  extraordinary 
than  many  of  the  previously  considered  families.  But  some  of 
them  have  the  habit  of  secreting  a  large  quantity  of  fluid  ;  and 
when  in  the  immature  stages,  certain  of  them,  have  the  art  of 
emitting  the  liquid  in  the  form  of  bubbles  which  accumulate 
round  the  Insect  and  conceal  it.  These  accumulations  of  fluid 
are  called  cuckoo-spits  or  frog-spits  ;  and  the  perfect  Insects  are 
known  as  frog-hoppers,  their  power  of  leaping  being  very  great. 
The  most  abundant  of  the  frog-hoppers  in  our  gardens  is 
riiiltii'iinx  xj>u iimri us,  a  little  Insect  of  about  a  quarter  of  an  inch 
long,  obscurely  coloured,  with  more  or  less  definite  pale  spots  ; 
it  is  so  variable  in  colour  that  it  has  received  scores  of  names. 
Some  of  the  Insects  do  not  use  their  fluid  in  this  manner,  but 
eject  it  in  the  form  of  drops,  and  sometimes  cast  them  to  a  con- 
siderable distance.  The  phenomena  known  as  weeping-trees  are 
due  to  Cercopidae;  some  of  the  species  make  such  copious  exuda- 
tions of  this  kind  that  the  drops  have  been  compared  to  a  showei 
of  rain.  In  Madagascar  it  is  said  that  /Y//r///.s  ijnn/loti  exudes 
so  much  fluid  that  five  or  six  dozen  larvae  would  about  lill  a 

1  Riley,  P.  enf.  Soc.   ?/W/ ///</'"".  iii.   1895,  p.   88.     For  tin-  ynun^.T  M.iijes  of 
M'-niliriii-isfoliata,  see  Tijdschr.  Eat.  (2)  iv.  1869,  pi.  viii. 

VOL.   VI  2   P 


5/8  HEMIPTERA-HOMOPTERA  CHAP. 

quart  vessel  in  an  hour  and  a  half.  The  frog-spit  is  considered 
by  some  naturalists  to  be  a  protective  device ;  the  larvae  are, 
however,  a  favourite  food  with  certain  Hymenoptera,  which  pick 
out  the  larvae  from  the  spits  and  carry  them  off  to  be  used  as 
stores  of  provision  for  their  larvae.  In  Ceylon  the  larva  of 
Jfurline/'ota.  guttigera  constructs  tubes  fixed  to  the  twigs  of  the 
tulip-tree,  and  from  the  tube  water  is  exuded  drop  by  drop. 
According  to  "Westwood,  this  Insect  is  intermediate  between 
Cercopidae  and  Membracidae.1 

Fam.  5.  Jassidae. — Ocelli  two,  placed  just  on  the  front 
margin  of  the  Itcad  (almost  in  a  line  with  the  front  of  the  eyes 
or  more  to  the  front]  or  on  the  de-flexed  frons.  Hind  tibiae 
usually  with  many  spines.  This  vaguely  limited  family  includes 
a  very  large  number  of  small  or  minute  Insects,  usually  of  narrow, 
parallel  form,  and  frequently  excessively  delicate  and  fragile. 
They  are  often  mentioned  under  the  name  of  Cicadellinae. 
Ashmead  distinguishes  two  families,  Bythoscopidae,  in  which  the 
ocelli  are  clearly  on  the  frons  or  front,  and  Jassidae,  in  which 
they  are  on  the  upper  edge  thereof.  Ulopa,  Lcdra,  and  a  few 
other  exceptional  forms,  are  also  by  many  distinguished  as 
representatives  of  distinct  families.  Very  little  is  actually  known 
as  to  the  life-histories  of  these  small  and  fragile  Insects,  but  it  is 
believed  that  the  eggs  are  usually  deposited  in  the  leaves  or 
stems  of  plants,  and  more  particularly  of  grasses.  In  North 
America  the  development  of  Deltocephalus  inimicifs,  from  hatching 
to  assumption  of  the  adult  form,  has  been  observed  by  Webster 
to  occupy  about  six  weeks.  As  Jassidae  are  numerous  both  in 
species  and  individuals  it  is  believed  that  they  consume  a  con- 
siderable part  of  the  vegetation  of  pastures.  Osborn  has 
calculated  that  on  an  acre  of  pasture  there  exist,  as  a  rule,  about 
one  million  of  these  hoppers,  and  he  considers  they  obtain  quite 
as  lar^e  a  share  of  the  food  as  the  Vertebrates  feeding  with 

O  O 

them. 

Fam.  6.  Psyllidae.  -  -Minute  Insects  u-ith  wings  usually 
transparent,  placed  in  a  roof -like  manner  over  the  liody  ;  with  tli  >•»• 
oi'i'ffi,  and  rather  long,  thin  a  nti'ii  nae  <tf  eight  to  ten  joints.  Tarsi 
t-i'-n-j, tinted. — These  small  Insects  have  been  studied  chiefly  in 
Europe  and  Xorth  America,  very  little  information  having  yet 
been  obtained  as  to  the  exotic  forms.  They  are  about  the 

1    Tr.  cut.  Soc.  London,  1886,  p.  329. 


VIII 


PSYLLIDAE 


579 


general 


appearance    remind 


size  of  Aphidae,  but  in  form  and 
one  rather  of  Cica- 
didae.  The  wings 
are  in  many  cases 
even  more  perfectly 
transparent  than 
they  are  in  many 
<  'ieadidae.  They  are 
sometimes  called 
springing  plant-lice, 
as  their  habit  of 
jumping  distin- 
guishes them  from 
the  Aphidae.  Low 
has  called  attention 
to  the  remarkable 
variation  in  colour 
they  present  in  con- 
formity with  either 
the  age  of  the  indi- 
vidual, the  food- 
plant,  the  climate, 
and,  more  particu- 
larly, the  season  of 
the  year.1  Reaumur  long  since  pointed  out  that  at  their  ecdy.-e< 
these  Insects  go  through  a  remarkable  series  of  changes  of  colour, 
and  Low  found  that  this  did  not  take  place  in.  the  normal 
manner  in  the  winter  generation  that  hibernates.  This  has 
been  confirmed  by  Slingerland  in  Xorth  America  in  the  case 
of  Psi/Un  pyricola?  which  has  been  introduced  there.  He  finds 
that  there  are  several  generations  in  the  year,  and  that  the 
hibernating  adults  differ  from  the  summer  adults  in  size,  being 
nearly  one-third  larger;  in  their  much  darker  colouring:  and 
especially  in  the  coloration  of  the  front  wings. 

In  the  earlier  stages,  1'syllidae  differ  greatly  in  appearance  from 
the  adult  forms ;  the  legs  and  antennae  in  the  newly  hatched  larvae 
are  short,  and  have  a  less  number  of  joints.  In  the  nymph  the 
shape  is  very  peculiar, the  lar-e  \\  inp-]iads  standing  out  horizontally 

•  /". /•/'/.  z.-b.  Clcs.   JJ'lcii,  xxvi.  1876,  ]>.  107. 

-  Coi-ii'!!  Univ.  A'jric.  cjy>.  st'iti«n  JlnUi-tin.  -44,  1892,  and  Hull.  108,  1896. 


FIG.    284. — Psi/Ua    mccinctn. 

Heeger. )     A,   larva  before  first 
third  moult.     C,  adult. 


15.     Europe.       (After 
moult.     B,  larva  after 


5  So  HEMIPTERA-HOMOPTERA  CHAP. 

from  the  sides  of  the  body,  so  that  the  width  of  the  creature  is  about 
as  great  as  the  length.  The  period  occupied  by  the  development 
apparently  varies  according  to  season.  "Witlaczil,  who  has  given  an 
account  of  many  details  of  the  anatomy  and  histology  of  various 
Psyllidae,1  considers  that  there  are  four  larval  stages ;  Heeger's 
account  of  Psylla  succincta  is  not  quite  clear  on  this  point,  and 
Slingerland  indicates  a  stage  more  than  this,  the  perfect  Insect 
being  disclosed  as  the  result  of  a  fifth  moult ;  it  is  probable  that  he  is 
correct.  In  these  earlier  stages  the  body  bears  long  hairs  called 
wax-hairs  ;  according  to  Witlaczil  in  the  young  larvae  of  certain 
species — Trioy  rlnnnni,  e.g. — these  are  broad  and  flat,  so  as  to 
make  the  body  appear  studded  with  oval  processes ;  he  states 
that  these  hairs  change  their  form  during  the  growth  of  the 
individual.  Xothing  is  more  remarkable  in  Psyllidae  than  the 
amount  of  matter  they  secrete  or  exude  from  their  bodies ;  in 
some  species  the  substance  is  a  "  honey-dew,"  and  the  nymph 
may  keep  itself  covered  with  a  drop  of  it :  in  other  cases  it  is 
solid,  as  shown  in  Reaumur's  figures  of  P.  bitxi,  where  this  exuda- 
tion forms  a  string  several  times  longer  than  the  body,  and  attached 
to  it.  Another  form  of  exudation  is  a  light  downy  or  waxy 
matter.  Slingerland  says  that  honey-dew  was  exuded  by  P. 
pyricola  in  such  quantities  that  it  "  literally  rained  from  the  trees 
upon  the  vegetation  beneath  ;  in  cultivating  the  orchard  the  back 
of  the  horse  and  the  harness  often  became  covered  with  the 
sticky  substance  dropping  from  the  trees.  It  attracts  thousands 
of  ants,  bees,  and  wasps,  which  feed  upon  it,"  The  writer  last 
year  observed  in  the  New  Forest  a  stunted  sloe-bush,  about  which 
a  large  number  of  Bombi  were  busily  occupied  ;  and  examination 
showed  that  they  were  thrusting  their  proboscides  into  the  curled 
and  deformed  leaves,  in  which  were  secreted  nymphs  of  a  Pxytln 
exuding  honey-dew.  It  must  not  be  assumed  that  this  honey- 
dew  is  the  excrement  of  the  Insect ;  this  also  is  known,  and  is  a 
different  substance.  Those  who  have  tasted  it  say  that  the 
honey-dew  has  a  clean,  good  flavour.  The  source  of  the  honey- 
dew  is  not  quite  certain,  but  it  seems  probable  that  it  comes,  like 
the  solid  matter  figured  by  Eeaumur,  directly  from  the  alimentary 
canal,  and  not  from  hairs  or  pores  on  the  body.  1'syllidae  give 
rise  to  definite  formations  or  galls  on  certain  plants;  sometimes 
these  I'syllid  galls  are  mere  changes  in  form  of  a  limited  part,  or 

.  iriss.  Zool.  xlii.  )88">,  pp.  569-638. 


VIII 


PSYLLIDAE APHIDAE  581 


parts,  of  a  leaf,  giving  rise  cither  to  crumpling  or  to  growth  of  a 
portion  in  one  direction  only,  so  that  on  one  surface  <>f  the  leaf 
a  swelling  is  formed,  and  on  the  opposite  side  a  more  or  less  deep 
cavity  in  which  the  Insect  dwells.  A  formation  of  this  kind  on 
the  leaves  of  Aegopoi //////>  /nii/n;/rnria  is  described  by  Thomas  T  who 
states  that  the  growth  is  due  to  the  deposition  of  an  egg  of  the 
PsylJa,  and  is  independent  of  the  after  life  of  the  Insect ;  a  fungus 
— J'lurin/ti  «i'f/<>/>tn/ii — forms  similar  structures  on  the  leaves. 
Structures  much  more  definite  than  this  may  be  the  result  of  the 
attacks  of  Psyllidae ;  for  an  example  the  reader  may  refer  to 
Reaumur's  account  of  Psi/f/n  l>n..d?  In  Australia  and  Tasmania 
there  are  Psyllidae  known  as  Laap  or  Lerp  Insects,  the  products 
of  which  are  called  leaf-manna  or  Lerp,  and  are  used  as  food. 
This  manna  is  a  scale  produced  by  the  young  Insect  on  the  leaves 
of  En  nil  if  pt  us  as  a  covering  or  protection.  The  scale  is 
fastened  to  the  leaf  by  a  hinge,  and  is  somewhat  like  the  shell 
of  a  cockle.  Although  the  scales  are  said  to  be  in  some  cases 
objects  of  great  beauty,  very  little  is  known  about  these  Australian 
Psyllidae,  one  of  which  has,  however,  been  referred  by  Schwarz 
to  the  genus  Spondyliaspis,  Signoret.3  About  100  species  of 
1'syllidae  are  known  to  occur  in  the  Palaearctic  region,  and  about 
fifty  of  them  have  been  found  in  Britain.4 

Fam.  7.  Aphidae  (Plant-lice  or  Green-fly,}- -Minute  Insects ; 
as  t/xi/nlli/  nirt  ir'ifli  destitute  of  wings,  though  many  individuals 
tirn  j>i/i/'s  of  transparent  icings.  Antennae  long,  or  /n  <»/>•/•- 
/<)////,  tlii'cc-  hi  ser  en-jointed  ;  abdomen  frequently  fit  !i  "  pair 
of  tubes  (.s//>//«//x),  or  short  processes  on  the  upper  side  of  the  fifth 
iili/loini  iial  si'ijinent.  Tarsi  two-jointed,  first  joint  so ///*•///// <.s 
excessively  short. — These  soft-skinned  Insects  are  frequently  called 
blight,  and  are  so  abundant  in  temperate  climates  that  a  garden, 
however  small,  is  sure  to  afford  abundance  of  specimens  during 
the  warm  months  of  the  year.  This  great  abundance  is  due  to 
peculiarities  in  the  physiological  processes  that  render  these 
obscure  little  animals  highly  important  creatures;  the  individual 
life  for  several  generations  is  restricted  to  constant,  or  at  any  rate 
copious,  imbibition  of  food, accompanied  by  an  almost  uninterrupted 

1  /<-lta,-1,r.  Naturw.  1.2}  xii.  1875,  p.  438. 

-  Uranium-,  Mi'in.  iii.  1737,  Dixie/m  .!/(///«//•.. 

'•'•  P.  ent.  soc.    H'tts/ri iii/tun,  iv.  1897,  p.  66. 

4  For  list  see  Scott,  Km.  M«,,.  xviii.  1882,  p.  253. 


582  HEMIPTERA-HOMOPTERA  CHAP. 

production  of  young  by  parthenogenetic  females,  the  young  so 
produced  becoming  rapidly  (sometimes  in  the  course  of  eight  or 
ten  days,  but  more  usually  in  about  twenty  days)  themselves 
devoted  to  a  similar  process ;  so  that  in  the  comparatively  short 
period  of  a  few  months  the  progeny  resulting  from  a  single 
individual  is  almost  innumerable.  This  remarkable  state  of 
affairs  is  accompanied  by  other  peculiarities  of  physiology,  with 
the  result  that  the  life-histories  of  successive  generations  become 
very  diverse,  and  complex  cycles  of  series  of  generations  differing 
more  or  less  from  one  another  are  passed  through,  the  species 
finally  returning  to  bi-sexual  reproduction,  and  thus  inaugurat- 
ing another  cycle  of  generations.  The  surprising  nature  of 
these  facts  has  in  the  last  150  years  caused  an  immense 
amount  of  discussion,  but  no  satisfactory  light  has  yet  been 
thrown  on  the  conditions  that  really  give  rise  to  the  exceptional 
phenomena.  These  phenomena  are  (1)  parthenogenesis;  (2) 
oviparous  and  viviparous  reproduction ;  (3)  the  production  of 
generations  of  individuals  in  which  the  sexes  are  very  unequally 
represented,  males  being  frequently  entirely  absent ;  (4)  the  pro- 
duction of  individuals  differing  as  to  the  acquirement  of  wings, 
some  remaining  entirely  apterous,  while  others  go  on  to  the 
winged  form  ;  (5)  the  production  of  individuals  of  the  same  sex 
with  different  sexual  organs,  and  distinctions  in  the  very  early 
(but  not  the  earliest)  stages  of  the  formation  of  the  individual ; 
(6)  differences  in  the  life-habits  of  successive  generations;  (7) 
differences  in  the  habits  of  individuals  of  one  generation,  giving 
rise  to  the  phenomenon  of  parallel  series.  All  these  phenomena 
may  occur  in  the  case  of  a  single  species,  though  in  a  very 
variable  extent. 

The  simple  form  of  Aphid  life  may  be  described  as  follows  :— 
eggs  are  laid  in  the  autumn,  and  hatch  in  the  spring,  giving 
rise  to  females  of  an  imperfect  character  having  no  wings  :  these 
produce  living  young  parthenogenetically,  and  this  process  may  be 
repeated  for  a  few  or  for  many  generations,  and  there  may  be  in 
these  generations  a  greater  or  less  number  of  winged  individuals, 
and  perhaps  a  few  males.1  After  a  time  when  temperature  falls, 

There  is  some  doubt  on  this  point,  as  the  earlier  observers  seem  to  have  supposed 
that  a  winged  individual  appearing  in  a  generation  chiefly  apterous  was  ipso  facto, 
a  male  ;  it  seems,  however,  to  be  certain  that  perfect  winged  males  appear  in  some 
species  in  generations  producing  no  perfect  sexual  females.  Speaking  generally, 


vin  APHIDAE  583 

or  when  the  supply  of  food  is  less  in  quantity,  or  after  a  period 
of  deliberate  abstention  from  food,  sexual  individuals  are  pro- 
duced and  fertilised  eggs  are  laid  which  hatch  in  the  spring,  and 
the  phenomena  are  repeated.  In  other  cases  these  phenomena 
are  added  to  or  rendered  more  complicated  by  the  intercalated 
parthenogenetic  generations  exhibiting  well-marked  metamorphosis, 
of  kinds  such  as  occur  in  apterous  or  in  winged  Insects  ;  while 
again  the  habits  of  successive  generations  may  differ  greatly,  the 
individuals  of  some  generations  dwelling  in  galls,  while  those  of 
other  generations  live  underground  on  roots. 

Parthenogenesis.  -  -  Eeturning  to  the  various  kinds  of 
peculiarities  we  have  enumerated  on  the  preceding  page,  we  may 
remark  that  the  phenomena  of  parthenogenesis  have  been 
thoroughly  established  as  occurring  in  Aphidae  since  Bonnet  dis- 
covered the  fact  150  years  ago ;  and  though  they  have  not  been 
investigated  in  much  detail  it  is  known  that  the  parthenogenesis 
is  usually  accompanied  by  the  production  of  young  all  of  the 
female  sex.  In  other  cases  males  are  parthenogenetically  produced  ; 
but  whether  these  males  come  from  a  female  that  produces  only 
that  sex  is  not  yet,  so  far  as  the  writer  knows,  established.  A 
note  by  Lichtenstein  :  suggests  that  usually  only  one  sex  is  pro- 
duced by  a  parthenogenetic  female,  but  that  both  sexes  are  some- 
times so  produced.  There  is  not  at  present  any  species  of  Aphid 
known  to  be  perpetuated  by  an  uninterrupted  series  of  partheno- 
genetic generations.  It  was  formerly  supposed  that  there  are  no 
males  at  all  in  Chermes,  but,  as  we  shall  subsequently  show,  this 
was  erroneous.  It  has,  however,  been  observed  that  a  series  of 
such  generations  may  be  continued  without  interruption  for  a 
period  of  four  years,  and  we  have  no  reason  to  suppose  that  even 
this  could  not  be  much  exceeded  under  favourable  conditions. 
The  parthenogenetic  young  may  be  produced  either  viviparously 
or  oviparously,  according  to  species. 

Oviparous  and  viviparous  reproduction. — The  distinction 
between  these  two  processes  has  been  extensively  discussed,  some 
naturalists  maintaining  that  they  are  thoroughly  distinct  «1> 
iiiitio.  This  view,  however,  cannot  be  sustained.  The  best 

the  course  of  events  seems  to  be  that  in  SHIIIIIHT  there  exist  only  wingless  and 
winged  parthenogenetic  females.  ,-unl  that  the  sexually  perfect  forms  appear  for  the 
first  time  in  autumn. 

1  Mitt.  Xcfiweiz.  cnf.  Gts.  iv.  187*5.  p. 


5  84  HEMIPTERA-HOMOPTERA  CHAP. 

authorities  are  agreed  that  in  the  earliest  processes  of  individual- 
isation  the  ovum,  and  the  pseudovum l  giving  rise  to  a  viviparous 
individual,  are  indistinguishable.  Leyclig,  Huxley,  Balbiani,  and 
Lemoine  are  agreed  as  to  this.  Nevertheless,  differences  in  the 
development  occur  extremely  early.  The  nature  of  these  differ- 
ences may  be  briefly  described  by  saying  that  in  the  viviparous 
forms  the  embryonic  development  sets  in  before  the  formation  of 
the  egg  is  properly  completed.  Balbiani  says,  "  In  fact  at  this 
moment  [when  the  viviparous  development  is  commencing]  the 
germ  [pseudovum]  is  far  from  having  obtained  the  development 
it  is  capable  of,  and  from  having  accumulated  all  the  matter 
necessary  for  the  increase  of  the  embryo,  so  that  the  evolution 
of  the  former  coincides,  so  to  speak,  with  that  of  the  latter.  On 
the  other  hand,  in  the  true  ovum  the  two  processes  are  chrono- 
logically separate,  for  the  rudiment  of  the  new  individual  never 
appears  before  the  egg  has  completed  the  growth  of  its  constituent 
parts."  As  regards  the  difference  in  structure  of  the  organs  of 
viviparously  an,d  oviparously  producing  individuals,  it  is  sufficient 
to  remark  that  they  are  not  of  great  importance,  being  apparently 
confined  to  certain  parts  remaining  rudimentary  in  the  former. 
Leydig,  indeed,  found  an  Aphis  in  which  certain  of  the  egg-tubes 
contained  eggs  in  various  stages  of  development,  and  others 
embryos  in  all  stages.3 

As  regards  the  physiology  of  production  of  winged  and  wing- 
less individuals  there  has  been  but  little  exact  inquiry.  Vast 
numbers  of  individuals  may  be  produced  without  any  winged 
forms  occurring,  while  on  the  other  hand  these  latter  are  occa- 
sionally so  abundant  as  to  float  about  in  swarms  that  darken 
the  air ;  the  two  forms  are  probably,  however,  determined  by  the 
supply  of  food.  The  winged  forms  are  less  prolific  than  the 
apterous  forms ;  and  Forbes  has  noticed  in  Aphis  maidi-radicis, 
where  the  generations  consist  partly  of  apterous  and  partly  of 
winged  individuals,  that  when  the  corn  begins  to  flag  in  conse- 
quence of  the  attacks  of  the  Aphis,  then  the  proportion  of 

1  The  term  pseudovum  is  applied,  as  a  matter  of  convenience,  to  the  earlier  condi- 
tion of  the  viviparously- produced  form,  and  the  term  pseudovarium  to  the  ovary 
producing  it. 

2  Balbiani,   Ann.   Sci.   Xat.   Zool.  (5)  xi.   1869,   p.  29.     For  concise  recent  re- 
marks on  the  early  embryonic  states,  see  Lemoinr,   Bull.   Soc.   cut.    France,  1893, 
p.  Ixxxix. 

3  Ada  Ac.  German,  xxxiii.  1869,  Xo.  2,  p.  81. 


vin  APHIDAE  585 

winged  individuals  becomes  large.1  The  appearance  of  winged 
individuals  is  frequently  accompanied  by  a  peculiar  change  of 
habit  ;  the  winged  individuals  migrating  to  another  plant,  which 
in  many  cases  is  of  a  totally  different  botanical  nature  from  that. 
on  which  the  apterous  broods  were  reared  :  for  instance  Aj>h  /.s 
>in///,  after  producing  several  apterous  generations  on  apple,  gives 
rise  to  winged  individuals  that  migrate  to  the  stems  of  corn  or 
grass,  and  feeding  thereon  commence  another  cycle  of  generations. 
The  study  of  this  sort  of  Aphis-migration  is  chiefly  modern,  but 
many  very  curious  facts  have  already  been  brought  to  light  ; 
thus  Drepanosiphum  i>l«t«  iioides,  after  producing  a  certain  number 
<>f  viviparous  generations  on  maple  (Accr\  quits  this  food-plant  for 
another,  but  after  two  or  three  months  returns  again  to  the 
maple,  and  produces  sexual  young  that  lay  eggs.2  Histories  such 
as  this  are  rather  common.  Even  more  interesting  are  the  cases 

O 

of  those  species  that,  after  some  weeks  of  physiological  activity 
on  a  plant,  pass  into  a  state  of  .repose  on  the  same  plant,  and 
then  after  some  weeks  produce  sexual  young.  On  the  whole,  it 
would  appear  that  the  appearance  of  winged  forms  is  a  con- 
comitant of  decreasing  nutrition.  It  is  a  very  remarkable  fact 
that  the  sexually  perfect  females  are  invariably  apterous,  and  this 
is  frequently.  also  the  case  with  the  males.  It  is  also  highly 
remarkable  that  the  sexually  perfect  individuals  are  of  com- 
paratively small  size.  There  are  at  least  three  kinds  of  males 
in  Aphidae  —  1,  winged  males  ;  2,  wingless  males  with  mouth 
well  developed;  3,  wingless  small  males  with  mouth  absent. 
As  regards  some  of  these  points  the  conditions  usual  in  Insect 
life  are  reversed.3  Huxley  inclined  to  treat  all  these  products  of 
a  fertilised  egg,  that  are  antecedent  to  another  process  of  ga  mo- 
genesis  (i.e.  production  with  fertilisation),  as  one  zoological  indi- 
vidual :  in  that  case  the  Aphis  zoological  individual  is  winged 
before  attaining  the  mature  state,  and  is  wingless  and  smaller 
when  mature.  Some  species  may  have  as  a  rule  two.  others 
three,  winged  generations  in  a  year. 

Parallel  series.  —  In  certain  cases  individuals  of  one  genera- 
tion   assume    different   habits,  and    so   set    up    the    phenomenon. 


1  Seventeenth  i:<  L>.  In*,,  -is  /////«</.•;,  ls<n,  ]..  06. 
3  Kr.—  Id.  Ada  Ac.  (!<  rmmi.  \\.  1S>7,  \>\>.  152,  153. 

3  In  connection  with  this  tin-  ulisence  of  a  functional  mouth   in  the  imago  state. 
of  numerou-  Lepidoptera,  and  of  Ostrid  Dij>U-ni,  .-hould  imt  IT  lu 


586 


HEMIPTERA-HOMOPTERA 


CHAP. 


known  as  parallel  series.  This  has  been  recently  investigated  in 
the  genus  Chermes  by  Blochmann,  Dreyfus,  and  Cholodkovsky. 
This  latter  savant  informs  us l  that  a  wingless  parthenogenetic 
female  of  C Ji.crm.es  hibernates  on  a  fir-tree — Picea  excelsa — and 
in  the  spring  lays  numerous  eggs ;  these  hatch,  and  by  the  effects 
of  suction  of  the  Chermes  on  the  young  shoots,  galls  are  formed 

(Fig.  286),  in  which  the  Insects  are 
found  in  large  numbers ;  when  they 
have  grown  the  galls  open,  and  allow- 
ing the  Insects  to  escape  these  moult 
and  become  winged  females.  They 
now  take  on  different  habits ;  some  of 
them  remain  on  the  Picea,  lay  their 
eggs  thereon,  and  out  of  these  there 
are  produced  young  that  grow  into 
hibernating  females,  which  next  spring 
produce  galls  as  their  grandmothers 
did ;  but  another  portion  migrates  to 
the  Larch  (Larix) ;  here  eggs  are  laid, 
from  which  proceed  wingless  partheno- 
genetic females,  that  hibernate  on  their 
new  or  secondary  plant,  and  in  the 

following    spring    lay    their    eggs    and 
FIG.  2So. — Chermes  alietis ;  \aber-       .  .  . 

nating   female    or    "winter-  give    rise    to    a    dimorphic    generation, 

mother."   Europe.    Much  mag-  fc       f    tl  becoming     nympllS     and 

limed.     (Alter  Cholodkovsky.)    •  J      L 

going    on     to    the    winged    condition, 

while  the  other  part  remain  wingless  and  lay  eggs,  that  give  rise 
to  yet  another  wingless  generation  ;  in  fact,  a  second  pair  of  parallel 
series  is  formed  on  the  new  plant,  of  which  one  is  wingless,  and 
exclusively  parthenogenetic,  and  continues  to  live  in  this  fashion 
for  an  indefinite  period  011  the  secondary  plant,  while  the  other 
part  becomes  winged ;  these  latter  are  called  sexuparous,  and  go 
back  to  the  Picea,  and  there  lay  eggs,  that  give  rise  to  the 
sexual  forms.  If  we  would  summarise  these  facts  with  a  view 
to  remembering  them,  we  may  say  that  a  migration  of  a  part  of 
a  generation  from  the  Picea  was  made  with  a  view  of  producing 
a  sexual  generation,  but  that  only  a  portion  of  the  migrants  suc- 
ceeded in  effecting  the  object  of  the  migration,  and  this  only  in 
their  third  generation.  Thus  portions  remained  on  the 

1  L.orae  Soc,  ent.  Ross.  xxiv.  1890.  p.  386. 


VIII 


APHIDAE 


5S7 


producing  unisexual  (female)  individuals,  and  a  portion  of  th«>sc 
that  emigrated  to  the  Larix  remained  thereon,  producing  also  uni- 
sexual (female)  individuals,  while  the  others  returned  to  the  J'ir«t 
and  produced  a  sexual  generation.  How  long  the  production  of 
the  unisexual  generations  may  continue  has  not  been  determined. 

Piriillo.i-rm. — The  Phylloxera,  that  has  caused  such  an  enor- 
mous amount  of  damage  in  the  Old  World  during  the  last  thirty 
years,  is  a  small  Aphid  that  was  introduced  from  Xorth  America 
into  Europe.  In  North  America  it  is  not  so  injurious  as  it  is 
in  Europe,  owing,  no  doubt,  to  slight  distinctions  in  the  condi- 
tions of  life  in  the  two  hemispheres,  as  one  of  which  maybe 
mentioned  that  in  Europe  a  larger  proportion  of  the  individuals 
produced  appear  to  confine  themselves  to  feeding  on  the  roots,  /'. 
vastatrix  being  one  of  the  species  that  lives  both  in  galls  on 
leaves,  and  underground  on  the  roots.  The  species  is  one  that 
exhibits  in  their  most  complex  form  the  peculiar  phenomena  of 
Aphid  life  we  have  already  mentioned.  It  has  probably  only 
one  congener,  Phylloxera  quercus,  and  of  this  Lichtenstein  say< 
that  in  its  cycle,  from  the  starting-point  of  the  winter-egg  to 
the  assumption  of  the  sexual  condition, 
it  exhibits  a  series  of  no  less  than 
twenty-one  forms.1  The  life  of  Phyl- 
loxera  mxtntrix  apparently  differs  essen- 
tially from  what  we  have  described  in 
Chermes,  inasmuch  as  the  migrations  are 
only  between  leaf  and  root  of  the  same 
plant — the  vine — and  not  from  one 
species  of  plant  to  another.  Some  autho- 
rities treat  Phylloxera  and  Chermes  as  a 
separate  family  under  the  name  of  Phyl- 
loxeridae. 

(lull*. — Like  Phylloxera,  many  species 

of  Aphidae  live  partially,  others  wholly,   Fl1-  286.— Gall,  or  la;-'  cone 

f   '  'herines  ulii-'ti.-i.      < 


i 


in  galls  that  are  produced  by  plants  as 
the  result  of  one  or  more  Aphids  inter- 
fering with  a  delicate  part  of.  the  plant 
when  it  is  in  a  voung  and  growing 

V  O 

slate.      The  usual  position  of  Aphid  galls 

is  on  a  leaf  or  leaf-stalk.      But  in  the  case  of  the 

/.it.  St,tf//i,  xxxvi.   1^7.". 


01 

l)rid<ti'.  Tlic  small  tiu'inv. 
;<  i  tin-  li-t'i.  is  a  srrtion  mack- 
at  the  k'\vl  iinlii-atfil  nv 
tin1  iniiiithii;1  litir  a.  and 
shows  tin-  rliainl>rr~  roiitain- 
iii'_r 


( 'hermes. 


588  HEMIPTERA-HOMOPTERA  CHAP. 

a  bud  ur  some  growing  part  of  the  spruce-fir  is  affected  in  such  a 
way  that  it  gives  rise  to  an  object  having  externally  the  appear- 
ance of  a  little  fir-cone,  while  inside  it  consists  of  chambers  in  which 
the  Aphids  reside.  The  forms  of  Aphid-galls  are  very  diverse,  but 
this  is  probably  due  to  the  plant  rather  than  to  the  Insect,  for  the 
same  species  of  Aphis  may  give  rise  to  different  forms  of  galls. 
Reaumur  thought  that  each  Aphid-gall  was  due  to  a  single  indi- 
vidual that  irritated  the  tissue  of  the  plant,  so  that  the  latter 
grew  up  at  the  point  of  irritation  and  enclosed  the  Insect. 

A  few  points  as  to  the  anatomy  of  Aphids  should  be 
noticed.  It  is  doubtful  whether  the  antennae  have  ever  really 
more  than  six  joints, the  apparent  seventh  joint  being  actually  a  sort 
of  appendage  of  the  sixth.  The  rostrum  is  externally  three-jointed, 
and  is  remarkable  for  the  great  diversity  in  its  length,  sometimes 
it  is  quite  short,  at  others  several  times  longer  than  the  body 
(Fig.  285);  the  setae  are  often  very  much  longer  than  the 
sheath  ;  in  cases  where  this  great  length  of  rostrum  exists,  the 
individual  may  often  be  found  with  the  tip  firmly  fixed  in  the 
bark,  and,  as  it  were,  tethered  by  means  of  the  rostrum,  the 
length  of  which  allows,  nevertheless,  considerable  locomotion. 
Suction  is  performed  by  contractions  of  the  pharynx.  There 
has  been  much  difference  of  opinion  as  to  whether  there  is  a 
salivary  syringe,  and  Witlaczil  failed  to  find  it.  Krassilstschik  is, 
however,  positive  that  it  exists,1  and  that  it  is  analogous  to  that 
described  by  Mayer  in  P'i/rrhocoris,]j\\t  there  are  great  differences 
of  structure  between  the  two.  It  is  very  difficult  to  determine 
the  number  of  segments  at  the  extremity  of  the  body ;  this  is 
terminated  dorsally  by  a  median  organ  placed  above  the  anus, 
and  known  as  the  cauda.  Balbiaiii  apparently  considers  that 
there  are  ten  abdominal  segments  and  the  cauda,  The  alimentary 
canal  has  a  small  stomach,  and  an  elongate  intestine,  the 
terminal  division  of  which  is  capacious  and  remarkably  long. 
There  are  no  Malpighian  tubes ;  according  to  Kowalevsky,  their 
function  is  discharged  by  the  posterior  part  of  the  alimentary 
canal.  There  exists,  however,  a  peculiar  structure,  the  pseudo- 
vitellus,  a  sort  of  cellular,  double  string ;  and  Witlaczil,  in  his 
valuable  paper 2  on  the  anatomy  of  Aphidae,  suggests  that  this 

1  ZwL  Anz.  xv.  1892,  p.  220. 

-  Arli.  7//s/.    H'icn,  iv.  1882,  Heft  iii.  p.  397  ;  see  on  this  organ  also  Morchvilko, 
Zool.  Anz.  xviii.  1895,  p.  357. 


VIII 


APHIDAE  589 


organ  may  in  some  way  replace  the  missing  Malpighian  tubes. 
Another  highly  peculiar  structure  is  the  siphons,  frequently 
called  nectaries,  honey-tubes,  or  siphuncles.  They  are  situated 
on  the  dorsal  aspect  of  the  fifth  abdominal  segment,  but  exist 
only  in  certain  of  the  sub-families;  they  are  of  very  different 
lengths  according  to  the  species,  and  are  capable  of  movement  : 
they  open  directly  into  the  body  cavity,  though  exceptional 
openings  into  the  body  cavity  are  extremely .  rare  in  Insect-. 
They  excrete  a  waxy  matter,  which  first  appears  as  oil -like 
globules.  It  was  formerly  supposed  that  they  were  the  means 
of  secreting  the  sugary  matter,  called  honey-dew,  so  much  prixed 
by  ants  and  some  other  Insects ;  but  this  is  now  ascertained 
to  be  erroneous.  This  matter  comes  from  the  alimentary  canal, 
and  is  secreted  in  large  quantities  by  some  species,  Biisgen  having 
observed  that  forty-eight  drops,  each  about  1  mm.  in  diameter, 
were  emitted  by  a  single  individual  in  twenty-four  hours.1  Certain 
gall-dwelling  Aphidae — Pemphigus,  Chermes  (Fig.  285),  S<'l'i~<>- 
neura — possess  numerous  wax  glands;  these  seem  to  replace  the 
siphons,  and  excrete  the  peculiar,  whitish  flocculent  matter  that 
is  so  conspicuous  in  some  of  these  Aphids. 

Earlier  anatomists  failed  to  find  any  dorsal  vessel,  and  it  is 
consequently  reported  in  books  to  be  absent.  It  has  been,  how- 
ever, recently  detected  by  "\Vitlaczil,  and  Mordwilko  states  that 
it  does  not  differ  from  that  of  other  Insects. 

We  have  already  alluded  to  the  fact  that  the  mode  of  repro- 
duction of  Aphids  leads  to  an  unrivalled  increase.  This,  however, 
is  not  due  to  the  prolificness  of  the  individual,  which,  in  point  of 
fact,  appears  to  be  considerably  below  the  average  in  Insects,  but 
rather  to  the  rapidity  with  which  the  young  begin  to  reproduce. 
This  has  been  discussed  by  Huxley,  Buckton,  and  others.  The 
first-named  naturalist  calculated  that  the  produce  of  a  single 
J/////'.s  would,  in  the  course  of  ten  generations,  supposing  all  the 
individuals  to  survive,  "contain  more  ponderable  substance  than 
five  hundred  millions  of  stout  men;  that  is,  more  than  the  whole 
population  of  China."  It  has  since  been  contended  that 
Professor  Huxley's  calculation  was  much  below  the  mark. 
Although  it  is  somewhat  difficult  to  make  a  calculation  dealing 
adequately  with  the  actual  facts,  yet  it  is  clear  that  the  increase 

1  Biol.  Centrum,  xi.  1891,  p.  193. 
2  See,  inter  alia,  "\Vebster,  /  Xew  York  ent.  Soc.  i.  1893,  p.  119. 


590  MEMIPTERA-HOMOPTERA  CHAP. 


of  Aphids  is  such  that,  drawing  as  they  do  their  nutriment 
directly  from  the  plant  in  its  growing  state,  in  the  course  of 
two  or  three  years  there  would  he  no  nutriment  available  for 
other  animals,  except  such  as  might  be  derived  from  plants  not 
attacked  by  Aphids.  The  numbers  of  Aphidae  would  be  so  great 
that  they  could  not  be  expressed  by  ordinary  numerical  methods, 
and  their  increase  would  be  actually  limited  only  by  the  relations 
existing  between  different  kinds  of  plants,  and  between  plants 
and  Aphids.  This  result  is  avoided  by  the  fact  that  Aphids  are 
themselves  the  victims  of  a  whole  army  of  Insect  -enemies.  They 
have  the  numerous  members  of  a  special  group  (Braconidae, 
Aphidiid.es)  of  minute  Hymenoptera  to  live  inside  their  bodies,  and 
many  Aculeate  Hymenoptera  depend  entirely  on  the  Aphidae  as 
the  source  of  food  for  their  own  progeny.  The  Lady-birds— 
Coccinellidae — live  on  Aphids  and  Coccids,  and  themselves  in- 
crease to  such  an  extent  as  to  be  in  many  years  a  conspicuous 
part  of  the  Insect  world.  Crowds  of  the  larvae  of  Hemerobiids 
and  Syrphids  are  constantly  engaged  in  spearing  and  sucking 
the  Aphides.  Hence  the  old  naturalist  Bonnet  said  that,  just 
as  we  sow  grain  for  our  benefit,  Nature  has  sown  Aphids  for  the 
benefit  of  multitudes  of  different  Insects.  He  might  have  added 
that  these  different  Insects  are  for  the  benefit  of  man,  it  being 
dear  that  without  them  the  population  of  the  world  must 
rapidly  decrease. 

Ants  treat  Aphidae  more  intelligently  than  most  other  Insects 
do,  for  they  do  not  destroy  the  helpless  creatures,  but  utilise 
their  products  in  the  way  man  does  those  of  the  cows  he  keeps. 
The  relations  between  ants  and  Aphids  is  itself  an  extensive 
chapter  in  Natural  History ;  many  facts  have  been  brought  to 
light  showing  that  the  ants  manage  the  Aphids  in  a  prudent  or 
intelligent  manner,  distributing  them  when  too  numerous  in  one 
place,  keeping  guard  over  them,  even  building  shelters  for  them, 
and  in  some  cases  keeping  them  in  direct  association,  by  retaining 
the  Aphids  in  their  own  dwellings.  The  further  investigation  of 
these  points  goes,  the  more  it  tends  to  raise  the  actions  of  the 
ants  to  the  level  we  call  in  ourselves  intelligent.  It  would  even 
;q>pear  that  the  ants  are  acquainted  with  the  migrations  of  the 
Aphids  from  one  species  of  plant  to  another,  Webster  informing 
us  that  as  the  Aphis-population  on  an  apple  tree  multiplied  the 
ants  in  attendance  anticipated  their  migration  to  wheat  and  grass 


VIII 


ALEURODIDAE 


591 


I. 


by  carrying  them  to  those  plants.1  We  have  nearly  200  species 
of  Aphidae  in  Britain,2  and  there  may  perhaps  be  800  known 
altogether.  To  what  extent  they  may  occur  in  the  tropics  is 
undetermined.  There  are  said  to  be  no  native  species  in  Xew 
Zealand. 

Fam.  8.  Aleurodidae. — Minute  Insects,  with  four  mealy 
seven-jointed  antennae,  two-jointed  feet,  terminated  by  two 
and  a  ///  //v/  process.  These  minute  Insects  are  at  present  a  source 
of  considerable  perplexity,  owing  to  the  curious  nature  of  their 
metamorphosis,  and 
the  contradictory 
accounts  given  of 
them.  In  the  earlier 
stages  they  are 
scale  -  like  and  qui- 
escent, being  fixed 
to  the  under  side  of 
a  leaf.  The  French 
authors  Signoret  and 
Girard  state  that  the 
young  are  hatched 
having  visible  ap- 
pendages and  seg- 
mentation, but  that 
after  they  are 
attached  to  the  leaf 
the  organs  gradu- 
ally suffer  atrophy. 
Maskell  states  the 
opposite,  saying  that 
the  organs  in  the 
earliest  stages  are  not  usually  recognisable,  but  become  faintly 
visible  with  the  growth  of  the  Insect.  Heeger  states  that 
the  larva  undergoes  three  ecdyses,  and  he  gives  the  figures 
we  reproduce  ;  if  he  be  correct  it  would  appear  that  the 
nymph  undergoes  a  great  development.  l,'<auiimr,  on  account 
apparently  of  their  great  metamorphosis,  treated  the 


C 


FIG.  287. — Instars  of  Aleurodes  immaculata.  Europe. 
(After  Heeger.)  A,  Nymph,  from  above  ;  B,  nymph, 
under  surface  ;  C,  imago. 


1  J.  Xi'n-  r<'/7-  Knl.  Soc.  i.  189.3,  p.  120.      Sec  also  as  to  knowledge  on  thr  pan 
of  ant-.   Forbes,   /v'/y///,.  ,iih  /,'<//.  //(>•«•«•/.%•  //////. »,X  IS'.M,  pp.  M,  rtr. 
-   Monograph  l>y  I'.iu-kton,  /.'".'/  .S'<»-/(7//,  4  vols.  1879-1883. 


592 


HEMIPTERA-HOMOPTERA 


CHAP. 


known  to  him  as  being  Lepidopterous,  though  he  correctly 
pointed  out  their  distinctions.  At  present  we  can  only  con- 
clude that  the  Aleurodidae  undergo  a  metamorphosis  of  a  kind 
peculiar  to  themselves,  and  requiring  renewed  investigation.  The 
family  has  been  monographed  by  Signoret,  and  more  recently  by 
Maskell,  who  has  increased  the  number  of  species  to  about  sixty.1 
We  have  three  or  four  in  Britain,  one  of  which,  A.  brassicae,  is 
extremely  abundant  on  various  kinds  of  cabbage  in  certain  years. 
Fam.  9.  Coccidae  (Scale  -  Insects,  Mealy -lugs}. -- Insects, 
usually  minute,  with  only  a  single  daw  to  the  foot ;  the  male  wi Hi 
one  pair  of  wings,  but  without  mouth-parts;  the  female 
and  usually  so  degraded  inform  that  most  of  the  external 
and  appendages  cannot  be  distinguished.  The  form  in  which  these 

Insects  are  most  generally  known 
is  that  of  a  small  scale  or  shell-like 
body  closely  adhering  to  leaves, 
fruits,  or  bark.  The  scales  are  of 
the  most  varied  form,  so  that  no 
general  description  can  be  given  of 
them.  The  scale  may  be  denned 
as  an  accumulation  of  excreted 
matter,  combined  with  the  cast 
skin  or  skins  of  the  Insect,  cover- 
ing the  body  either  totally  or 
partially,  and  thus  acting  as  a  shield 
undOT  whioh  the  """sequent  devel- 

a    female    scale    magnified.      (After    Opllieilt   takes  place.        All    Coccidae 

do  not  form  scales  ;   but  the  habit  of 

excreting  a  large  quantity  of  peculiar  matters  to  the  outside  of 
the  body  is  universal ;  this  excreted  substance  is  frequently  white, 
and  of  a  powdery  nature,  and  Coccids  of  this  kind  are  known  as 
mealy-bugs.  In  other  cases  the  exudation  is  like  shell  or  glass, 
and  the  creature  may  become  quite  encysted  therein.  In  this  way 
the  forms  of  Cocidae  known  as  "ground- pearls"  are  formed.  "When 
first  hatched  from  the  egg  Coccidae  are  mite-like  creatures,  and  it 
is  only  subsequently  that  the  females  lose  the  power  of  loco- 
motioii.  The  females  of  numerous  forms  of  Coccidae — more 
particularly  the  mealy-bugs — do  not  lose  the  antennae  and  legs. 
There  is  also  a  group  (Brachyscelides)  of  Coccids  that  live  in 

1    Tr.  Xew  Zealand  Inst.  xxviii.  1895. 


VIII 


COCCIDAE SCALE-INSECTS 


593 


galls.  This  highly  aberrant  group  is,  however,  peculiar  to 
Australia ;  elsewhere  very  few  gall -making  Coccids  have  been 
discovered. 

There  are  upwards  of  800  species  of  Coccidae  at  present 
known.1  The  family  was  monographed  by  Signoret  about  twenty- 
five  years  ago,  and  since  then  there  has  been 
very  much  matter  concerning  them  published 
in  a  scattered  manner.2  No  general  work 
lias  been  published  on  the  British  species, 
but  Mr.  Newstead  is  preparing  one.  The 
classification  of  Insects  so  minute  as  Coc- 
cidae, and  with  such  extreme  difference  in 
the  sexes,  is,  of  course,  a  matter  of  great 
difficulty ;  the  best  divisions  are  those  given 
by  Green  in  his  Coccidae  of  Ceylon? 

The  fact  that  there  is  only  one  pair  of 
wings  in  the  perfect  male  Coccid  would  appear 
to  ally  these  Insects  with  the  Diptera ;  these 
( '( x-cidae  have,  too,  like  the  Diptera,  a  small 
appendage  on  each  side  of  the  metathorax. 
Witlaczil  shows  that  these  little  processes  may 
really  represent  a  pair  of  wings,  inasmuch  as 
they  are  developed  from  imperfect  folds  of 
hypodermis,  i.e.  imaginal  discs.  Beyond  these 
facts  and  the  occurrence  in  certain  females 
(Margarodes)  of  a  great  histolysis  during  the 
post-embryonic  development,  there  is  nothing  to  indicate  any  rela- 
tionship between  Coccidae  and  Diptera.  It  has  been  shown  by 
liiley  that  these  little  processes,  in  some  forms,  serve  as  hooks  to 
attach  or  control  the  true  wings,  and  this  function  is  never  assumed 
by  the  haltcivs  of  Diptera.  Although  Coccidae  are  placed  next 
Aphidae,  yet  the  two  families  appear  to  be  really  very  different. 
The  modes  of  reproduction  so  peculiar  in  Aphidae  reappear  to  a 
certain  extent  in  Coccidae,  but  are  associated  with  prol'mmd 

1  Acatalogue  of  Coccidae  has  recently  been  published  by  Mr.  T.  D.  A.  (,'nrk,  i,  !1 
in  7,V//.  Illinois  !.«!>.  iv.  1896,  pp.  318-339. 

2  Sigiioivt's   papers  are  to  be  found  in  eighteen  parts  in  Ann.  .S'oc.  ent.  France, 
1868  to  1876  :   the  most  considerable  subsequent  systematic   paper-  are   those  1>\ 
Maskell  in  the  Transactions  of  the  New  Zealand  Instituh  from  L878  to  the  present 
time. 

3  Coccidae  </(V///»/<,  pt.  1,  1896,  p.  16. 

VOL.   VI  -    i.! 


289.  — 

Female 
on    portion   of   a    6g 
leaf.     (After  Berlese.) 


594  HEMIPTERA-HOMOPTERA  CHAI-. 


distinctions.  Though  the  viviparous  method  of  reproduction 
and  parthenogenesis  occur  in  Coccidae,  yet  they  are  only  ex- 
ceptional, arid  they  are  not  put  to  the  same  uses  by  the  species 
that  exhibit  the  phenomena.  Thus  we  have  seen  that  in  Aphid;n- 
generations  of  imperfect  individuals  are  produced  with  rapidity, 
while  the  individual  is  not  directly  very  prolific.  In  Coccidae 
the  reverse  is  the  case — the  generations  are  usually  similar  to 
one  another;  they  do  not,  as  a  rule,  follow  with  rapidity,  and  the 
female  is  usually  very  prolific,  thousands  of  young  being  some- 
times produced  by  a  single  individual  The  extraordinary  poly- 
morphism, of  the  species  of  Aphidae  is  not  exhibited  by  Coccidae, 
though,  contrary  to  what  we  find  in  Aphidae,  the  males  and 
females  are  usually  excessively  different.  The  two  families  ;jp- 
parently  also  differ  in  that  Coccidae  are  specially  characteristic 
of  warm  climates,  Aphidae  of  the  temperate  regions. 

Parthenogenesis.  Owing  to  the  fact  that  the  males  are  very 
minute  creatures,  totally  different  from  the  females,  and  living 
but  a  very  short  time,  they  were  but  little  known  to  the  earlier- 
observers.  It  was  therefore  only  natural  to  suppose  that  par- 
thenogenesis was  very  common.  Of  late  years  the  males  of  a  great 
many  species  have  become  known,  so  that  ordinary  sexual  repro- 
duction must  be  considered  as  the  normal  method  in  Coccidac, 
although,  in  the  great  majority  of  cases,  the  male  is  still  unknown. 
It  has,  however,  been  shown  in  numerous  cases  that  parthenogenesis 
may  occur  even  when  males  exist;  and  there  are  some  abundant 
species  of  which  it  has  not  been  possible  to  find  a  male.  In 
1887  Moniez1  announced  that  he  had  discovered  the  male  of 
Lecaniuin  hesperidwm  ''one  of  the  notoriously  parthenogenetic 
species)  in  an  ovarian  cul-de-sac  in  the  body  of  the  female,  and 
he  therefore  considers  that  sexual  reproduction  occurs.  II'-  does 
not  say  how  pairing  takes  place,  and  we  are  not  aware  that  his 
observation  has  been  confirmed.  If  correct  it  will  be  ner-cssary 
to  reconsider  the  whole  question  as  to  parthenogenesis  in 
Cocci  due.  Apterous  males  are  known  in  two  or  three,  species. 

The  post-embryonic  development  of  Coccidae  is  of  the  most 
unusual  character.  It-  is  fjuitc  different/  in  the  two  sexes,  and  in 
each  of  them  it  presents  features  not  found  elsewhere.  It  has, 
however,  as  yet  been  studied  in  only  a  lew  forms,  and  even  in 
them  is  incompletely  known.  When  h;itehed  from  the  egg 

1   d.  li.  A<:.  -S'a.  I'nrit,  civ.  1887,  f.  4-U*. 


VIII 


COCCIDAE-— SCALE-INSECTS 


:      : 


the  young  Coccids  are  all  similar,  male  and  female  being  indistin- 
guishable.     A   difference 
soon    appears,    with    the 


that  the  male,  after 
passing     through     more 
than    one    pupal    condi- 
tion, appears  as  a  winged 
Insect.    The  female  never 
becomes    winged,    but,   if 
\\e   may  judge   from  the 
incomplete  accounts  we  at 
present    poss  ss,   her    de- 
velopment   varies    much 
>>rding  to  species.      In 
some  she  retains  the  legs, 
antennae,     and     mouth- 
"rgans  ;    in    others    she 
loses  these  puts,  though 
retaining     the     original 
form  in  a  general  manner; 
while   in  a    third  (J/ar- 
gnrorfes)  she  becomes  en- 
cysted,   and    apparently 
suffers   an    almost    com- 
plete histolysis.  reappearing  after  a  very  long  period  (it  is  said 
it  may  be  as  much  as  seven  years)  in  a  considerably  altered  form. 
The   post-embryonic  development  of  Aspidiotus  ncrii  has  1 
studied  by  Schmidt *  and  Witlaczil/  whose  accounts  agree  exi 
as  to  some  points,  such  as  the  number  of  eedyses.     The  young, 
larva,  is  hatched  with  fairly  well-developed  legs,  antennae, 
rostrum :  there  is  no  external  difference  between  the  sexes.      I 
larva  selects  some  spot  on  the  plant  and  drives  its  rostrum  t 
thus  becoming  fixed;  moults  occur,  and  the  bodv  exeiv:  -  waxy 

• 

matter  from  its  sides  in  processes  that  fell  together  auc" 
shield;   the  female  becomes  much  larger  than  the  male. 
-  and  antennae  of  both  sexes  disappear,  so  that  the  p< 
.ent  is  completely  lost.    The  mouth-parts  also  at 
after   this   undergoes  no   further  chance,  ex 
growth   in   connection   with   ovarian 

.Yu/Hiyr«A.  li.  i.  1SS5.  p.  169.       s  ZfitftAr.  tcifs. 


FIG.  '290. — Instars  of  rkiftyfojrins  citri.  (After  Ber- 
lese.'t  A.  Egg ;  B.  youug  larva  :  C,  first  male 
nymph  :  D.  second  male  nymph  :  E.  adult  male  : 
F,  adult  female.  All  equally  iiugnilietL 


596 


HEMIPTERA-HOMOPTERA 


CHAP. 


however,  continues  development ;  notwithstanding  the  impossi- 
bility of  taking  food,  owing  to  the  absence  of  a  mouth,  it  increases 
much  in  size,  and  the  organs  of  the  future  perfect  Insect 
commence  to  develop  from  imaginal  discs  in  a  manner  similar  to 
that  which  occurs  in  the  Dipterous  genus  Corethra ;  no  mouth- 
parts  are  however  developed,  these  being  merely  represented  by 
spots  of  pigment,  or  rudimentary  additional  eyes.  The  wings 
are  developed  outside  the  body.  Difference  of  opinion  prevails  as 
to  the  nature  of  the  instars  between  the  young  larva  and  the 
imago.  It  is  clear,  however,  that  Fig.  291,  D,  corresponds  fairly 


FIG.  29i. — Development  of  male  of  Aspidiotus  nerii.  A,  Newly  hatched  larva  ;  B, 
prae-pupal  instar  ;  C,  pupa  before  ecdysis  ;  D,  pupa  shortly  before  the  emergence 
of  the  imago  :  a,  antenna  ;  e,  eye  ;  /,  wing-rudiment  ;  I,  leg  ;  o,  basal  part  of 
mouth-organs.  (After  Schmidt.)  Magnification  not  definitely  stated. 

with  the  pupa  of  Insects  with  complete  metamorphosis,  and  the 
instars  shown  in  Fig.  291,  B,  C,  may  therefore  be  looked  on  as 
equivalents  of  the  resting-larva  stage  of  ordinary  Insects  with 
complete  metamorphosis.  Witlaczil  considers  this  development 
to  be  a  condition  of  incomplete,  approaching  very  nearly  to 
complete,  metamorphosis.  The  condition  is  perhaps  more  pre- 
cisely estimated  if  we  recollect  that  winged  Insects  are  divided 
into  two  series,  in  one  of  which  the  wings  are  developed  outside 
the  body  ;  in  the  other,  inside  the  body.  The  Insects  with  very 
complete  metamorphosis  all  belong  to  the  second  of  these  two 
series,  while  in  the  male  Coccid  we  have  the  highest  form  of 
metamorphosis  attained  by  any  of  the  first  series.  As  regards 
the  development  of  the  female  encysted  nymph  or  pupa, 
previously  alluded  to  as  being  found  in  the  "  ground-pearls  "  of 


vin  COCCIDAE SCALE-INSECTS  597 

the   genus   Maryi<i'<><li'x,   we   can   at  present   offer   the    reader   no 
satisfactory  account.1 

Products  of  Coccidae. — Honey-clew  is  secreted  by  Coccidae, 
but  as  a  rule  not  so  extensively  as  by  Aphidae  and  some  other 
Homoptera  ;  nevertheless,  it  is  often  sufficient  to  make  the  plants 
frequented  by  Coccids  very  sticky  and  unclean.  Some  species 
make  a  really  extensive  exudation  of  such  matter.  Reaumur 
records  that  a  Coccid,  which  is  doubtless  Lecanium  persicae, 
excretes  a  supply  of  honey-dew  that  drips  to  the  ground  ;  he  s;iys 
it  tastes  sweet  and  nice.  The  manna  mentioned  in  the  book  of 
Exodus  is  pretty  certainly  the  honey-dew  secreted  by  Coccus  (n<  iw 
Gfossyparia)  mannifera,  which  lives  on  Tamarix  in  many  places 
in  the  Mediterranean  basin.  This  substance  is  still,  called  by  the 
Arabs  "  Man,"  and  is  used  as  food ;  in  its  natural  state  it  is  a 
substance  very  like  honey ;  it  is  doubtless  excreted  by  the 
Coccus,  and  is  not  produced  directly  by  the  Tamarix  as  some 
have  supposed.  Waxy  matters  are  produced,  by  several  Coccidae. 
Ceroplastes  ceriferus,  a  Lecaniid,  produces  white  wax  in  India. 
Ceroplastes  is  a  widely  distributed  genus,  and  various  species  of  it 
have  been  used  for  the  purpose  of  producing  wax  in  other  parts 
of  the  world.  The  white  wax  of  China  is  understood  to  be  pro- 
duced by  another  Lecaniid,  Uricerus  pela  ;  but  little  is  known  as 
to  this  Insect ;  it  is  said  that  the  wax  is  produced  by  the  winged 
males.  The  substance  was  formerly  greatly  prized  in  China,  but 
is  falling  into  disuse  on  account  of  the  introduction  of  Kerosene. 
Lac  is  produced  by  Carteria  Ictcca,  a  Lecaniid  living  in  India  on 
Anona  sqiiamosa,  as  well  as  on  species  of  Ficus,  Rliamnus  and 
other  trees ;  the  lac  is  the  shelly  scale  produced  by  the  Insect 
as  a  covering ;  it  is  composed  in  larger  part  of  resinous  matter, 
with  which  there  is  mixed  a  comparatively  small  quantity  of  wax 
and  other  substances.  The  body  of  this  Insect  also  affords  the 
red  substance  called  lake.  Various  species  of  Kermes  formerly 
afforded  a  red  dye  well  known  to  the  Greeks  and  Romans.  These 
Insects  live  on  Quercus  cocci/era  in  the  Mediterranean  region.  A 
medicinal  syrup  is  also  obtained  from  them.  PorphyropJiora 
polonica  was  used  in  North  and  Central  Europe  for  the  same  pur- 
poses as  Kermes ;  it  is  a  Coccid  living  on  the  roots  of  !'<>/ >/</<> ninn 
cocciferum.  These  European  Insects  were  replaced  commercially 

1  For  summary  as  to  our  present  knowledge  of  this  curious  condition  of  Insect 
life,  see  Mayet,  Ann.  Soc.  cnt.  France,  1896,  p.  419. 


HEMIPTERA-HOMOPTERA  CHAP. 

after  the  discovery  of  America  by  the  cochineal  Insect,  Coccus 
cacti,  a  Mexican  Coccid  feeding  on  a  Cactus  called  Nopal 
(Opuntia  coccinellifera).  This  Insect  was  subsequently  introduced 
to  the  Eastern  hemisphere,  and  was  established  with  more  or 
less  success  in  a  few  spots  on  the  borders  of  the  Mediterranean. 
In  the  Canary  Islands  it  flourished  on  other  species  of  Cactus-, 
became  acclimatised,  and  was  the  object  of  an  extensive  commerce. 
The  colour  in  the  case  of  all  these  Coccid  dyes  was  obtained  from 
the  bodies  of  the  Insects,  in  the  tissues  of  which  it  is  contained. 
The  dyes  have  now  been  largely  displaced  in  commerce  by  the 
derivatives  of  Aniline.  Axin  is  produced  by  the  Mexican  Coccid 
Llaveia  axinus ;  this  substance  appears  to  be  of  a  very  peculiar 
nature  ;  it  is  apparently  chiefly  fatty,  and  contains  a  peculiar  acid, 
axinic  acid.  Axin  is  used  as  an  external  medicinal  application 
in  various  affections ;  and  it  is  also  employed  as  a  varnish ;  it 
dries  and  hardens  on  exposure  to  the  air,  and  is  said  to  be  of 
considerable  value.1  In  our  British  genus  Orthczia  the  body  of 
the  female  is  completely  covered  with  a  symmetrical  snow-white 
armour,  from  which  project  the  pink  legs  and  antennae.  This  is 
one  of  the  forms  in  which  the  female  preserves  the  legs  to  the 
end  of  her  life.  The  objects  called  ground-pearls,  already  alluded 
to,  have  long  been  known  in  various  parts  of  the  world,  and  in 
the  island  of  St.  Vincent  they  are  sufficiently  large  to  be  collected 
and  strung  for  necklaces.  These  bodies  are  the  encysted  pupae 
of  Coccids  of  the  genus  Margarodes ;  the  cyst  is  said  to  be  of 
chitin.  M.  vitis  commits  serious  ravages  on  the  vines  in  Chili 
by  sucking  their  roots,  and  it  is  probable  that  all  the  species  are 
of  subterranean  habits ;  this  would  partially  explain  the  fact 
that  very  little  is  known  about  the  history  of  these  pearls, 
though  naturalists  have  been  acquainted  with  them  for  many 
years. 

The  gall-making  Coccids  of  the  group  Brachyscelides  have 
only  recently  been  at  all  investigated ;  the  galls  they  give  rise 
to  are  sometimes  about  a  foot  in  length,  and  there  appear  to  be 
numerous  species  and  several  genera  in  Australia ;  they  are 
especially  abundant  on  Encalyirfvs  and  Acacias.  The  females  are 
highly  remarkable  from  the  variable  conditions  the  legs  assume, 
so  that  in  some  cases  they  may  be  described  as  biped  Insects,  the 

1  For  additional  information  as  to  useful  Coccidae,  see  Blanchard,  Bull.  tioc.  Zool. 
France,  viii.  1883,  p.  217. 


vni  ANOPLURA LICE  599 

hind  legs  remaining,  though  the  others  have  atrophied.1  Very 
little  indeed  is  known  as  to  these  Insects.  One  of  the  most 
peculiar  points  of  their  economy  appears  to  he  that  the  galls 
giving  rise  to  males  are  different  from  those  producing  females. 

An.oplu.ra  or  Lice. 

Small  Insects  with  thin  integument ;  entirely  wingless,  the 
three  thoracic  segments  indistinctly  separated ;  the  head 
hearing  in  front  a  short  tube  furnished  ivith  hooks;  from  which 
tube  there  can  be  protruded  another  very  delicate  sucking- 
tube.  Feet  terminated  by  a  single  long  clau:  The  Anoplura, 
Pediculidae,  or  lice  are  disgusting  Insects  about  which  but  little 
is  known.  The  most  contrary  opinions  have  been  expressed  as 
to  their  mode  of  taking  their  nourishment,  which  is,  without 
exception,  the  blood  of  Mammals  ;  on  the  bodies  of  which  they 
pass  the  whole  of  their  life.  It  is  a  most 
difficult  matter  to  examine  their  mouth ; 
the  best  information  on  this  point  is  given 
by  Schiodte  and  Graber,  but  though  these 
two  authorities  agree,  their  results  are  very 
incomplete,  and  do  not  warrant  us  in  ex- 
pressing a  confident  opinion  as  to  the  nature 
of  the  relationship  between  Hemiptera  and 
Anoplura — a  question  that  has  been  for 
lonf  a  moot  one.  The  short  tube  furnished 

O 

with  hooks  in  front  (Fig.  293,  rf)  is  con- 
sidered to  be  the  lower  lip,  and  the  tube 
inside  is,  it  is  suggested,  a  combination  of  FIG.  292.— TW/.W,/* 

tis,    9.     Human    head. 
the    homologues    of    maxillae    and    mandi-        (After  Piaget. ) 

hies;   there  is  also  what  may  be  a   labrum 

(//)  ;  and  inside  the  head  a  framework,  at  any  rate  analogous  to 
if  not  homologous  with,  the  parts  of  this  kind  we  have  described 
as  existing  in  Hemiptera.  All  the  parts,  with  the  exception  <>!' 
the  basal  tube  or  head  of  the  beak,  are  of  the  most  minute  and 
delicate  nature,  so  that  it  is  difficult  to  see  their  form  or  com- 
prehend their  relations.  It  is  evident  that  they  are  very  dit'li-ivnt 
anatomically  from  the  mouth-parts  of  Hemiptera;  still  there  is 

1  Rubsaamen's  paper  on  these  Insects  gives  references  to  most  of  the  previous 
literature,  Berlin,  ent.  Zeitschr.  xxxix.  1894,  p.  199. 


6oo 


ANOPLURA 


CHAP. 


sufficient  general  resemblance  to  warrant  the  belief  that  the  parts 
in  the  two  may  ultimately  be  shown  to  be  also  morphologically 

similar.  If  Meinert  be  correct,  this 
view  will,  however,  not  prove  to  have 
any  foundation.  He  considers  that 
morphologically  the  mouth  of  the  louse 
has  no  similarity  to  that  of  the  bug ; 
the  protrusible  parts  in  the  former  he 
considers  to  be  modifications  of  epi- 
pharynx  and  hypopharynx  ;  and  the 

rod-like  structures  to  be  hypopharyngeal 
Fia.    293.  —  Mouth  -  organs    of   i.,iripiinp  .    arir]  4-1,  q  4-  4-ilpv  .,rp  4-1, „„  fnrallv 

louse.     (After  Graber.)    b,  c,    lameiiae  >    and  3tall7 

chitinous     envelope     into  different  from  the  setae  of  bugs.1      He 

which  the  beak  can  be  with-  •  i  T  •  -<•   ,  -          V\    i          r 

drawn  ;  d,  head  of  the  beak,  considers  Lice  to  be  a  distinct  Order  of 
with  crown  of  spines ;  g,  Insects  for  which  he  proposes  the  name 

labrum  ;     h,    delicate    tube    Q-    i  i 

protruded  (very  rarely  seen    ^IpHUnCUiaiJa. 

in  this  state) ;  m',  unpaired         The   alimentary   canal   and   nervous 

system    resemble    those    of  Mallophaga 

more  than  they  do  those  of  Hemiptera.  The  oesophagus  leads 
into  a  large  stomach  bilobed  in  front ;  at  the  posterior  extremity 
of  this  there  open  the  four  Malpighian  tubes,  and  behind  these 
there  is  a  well-marked  small  intestine.  The  nervous  system 
consists  of  a  cephalic  ganglion  and  of  three  other  closely  approxi- 
mated ganglia,  the  posterior  one  the  larger.  It  remains 
doubtful  whether  or  not  the  first  of  these  three  ganglia  is  the 
infra-oesophageal  one.'J 

The  species  -of  lice,  so  far  as  known,  are  not  numerous,  some 
six  genera  and  about  forty  species  being  all  that  are  recorded ; 
they  occur  on  various  kinds  of  mammals,  including  some  that  live 
in  water.  Seals  have  a  genus,  Echinophthirius,  peculiar  to  them. 
Monkeys  are  specially  liable  to  be  affected  by  lice ;  the  genus 
that  chiefly  occurs  on  them  is  Pedicinus,  a  very  distinct  one,  in 
which  there  are  only  three  instead  of  five  joints  to  the  antennae. 
Perhaps  the  most  remarkable  louse  is  Haematomyzus  elephantis, 
that  of  the  elephant ;  it  has  a  long  proboscis  in  front  of  the  head. 
As  a  rule  each  species  of  louse  is  confined  to  one  species  of  Mam- 
malia, or  to  very  closely  allied  forms.  Man  is  said  to  be  infested 

1  Ent.  Mcddcl.  iii.  1891,  p.  82. 

2  Cf.  Graber,  Zeitschr.  wiss.  Zool.  xxii.  1872,  p.   165,  and  Landois  in  the  same 
Journal,  xiv.  1864,  p.  24. 


vni  LICE  60 1 

by  three  species,  Pediculus  capitis,  P.  vestimenti  and  Phthirius 
inguinalis ;  Meinert  is  of  opinion  that  P.  capitis  and  P.  vestimenti 
are  only  one  species,  and  Schiodte  appears  also  to  have  thought 
this  probable.  Andrew  Murray  was  of  opinion  that  the  brads 
of  different  varieties  of  men  are  infested  by  distinct  varieties  of 
P.  capitis.  His  conclusion  was  chiefly  base&.  on  examination  of 
specimens  preserved  by  Charles  Darwin  ;  it  requires  confirmation. 
Very  little  is  known  as  to  the  life-history  of  the  louse.  Leemvrn- 
hoek  made  himself  the  corpus  vile,  for  an  experiment,  from  which 
he  concluded  that  the  Pediculus  vestimenti  is  very  prolific.  That 
scientific  men  did  not  know  whether  the  louse  bites  or  sucks  was 
formerly  made  the  ground  for  a  taunt.  Schiodte  has  given  an 
almost  pleasing  account  of  the  way  in  which  he  settled  this,1 
showing  that  the  sucking  action  is  beyond  all  doubt.  Accounts 
of  disease  called  Phthiriasis,  attributed  to  lice,  are  to  be  found  in 
many  old  books,  but  the  evidence  does  not  warrant  us  in  believing 
anything  more  than  that  persons  suffering  from  some  disease,  and 
in  a  neglected  and  filthy  condition,  were  horribly  infested  with 
these  disgusting  Insects. 

It  is  usual  to  say  that  Pediculidae  are  Hemiptera  degraded  by 
a  long  exclusive  persistence  in  parasitic  habits.  At  present, 
however,  this  must  be  looked  on  as  a  pious  opinion,  rather  than 
as  an  induction  from  our  knowledge  of  their  morphology  and 
embryology ;  for  this  is  at  present  too  imperfect  to  warrant  any 
final  conclusion. 

1  Ann.  Nat.  History  (3),  xvii.  1866,  p.  213. 


NOTE. 

Since  the  remarks  on  the  classification  of  Hymenoptera  were  written  Mr. 
"W.  H.  Ashmead  has  published  several  important  papers  proposing  a  classi- 
fication, to  a  considerable  extent  new.  He  adopts  10  superfamilies  and  94 
families.  His  views  are  summarised  in  P.  U.  S.  Mus.  xxiii.  No.  1206,  1900. 
Pastor  Konow  has  also  discussed  this  subject  in  Ent.  Nadir,  xxiii.  1897,  pp. 
148-156. 


INDEX 


Every  reference  is  to  the  page  :  words  in  italics  are  names  of  genera  or  species  ;  figures 
in  italics  indicate  that  the  reference  relates  to  systematic  position  ;  tigures  in  thick 
type  refer  to  an  illustration  ;  f.  =  and  in  following  page  or  pages  ;  u.  =  note. 


Abdomen,  of  Chrysis,  2  ;  of  Coleoptera, 
185  ;  of  Diptera,  446  ;  of  Hemiptera, 
538  ;  of  Lepidoptera,  313  ;  of  Thy- 
sanoptera,  528 

Abdominal  legs,  9 

Abeille-perce-bois,  33 

Abeille  tapissiere,  51 

Abis2)(t,  77 

Acacia  fistulosa,  beetles  in,  213 

Acalyptrate  Muscida,  4^4 

Acanthia,  560 

Acanthomeridae,  483 

Acanthosoma  griseum,  546 

Acari,  relations  to  Insects,  220,  223,  238, 
530 

Acentropiis,  425 

Acephalons  larvae,  449 

Achreioptera,  219 

Acraeides,  350 

Acridium  maroccanum,  254 

Acrocera  globuius,  490 

Acroceridae,  489 

Acronycta,  418 

Actias  lima,  374 

Actiidae,  510 

Acutilingues,  30 

Adapted  excrement,  284,  284,  380 

Adelops,  221 

Adeusamer,  on  Ascodlpteron,  520 

Adephaga,  190,  200  f.,  S16,  234 

Adimeridae,  240 

AtUmerus  setosus,  241 

Adlerz,  on  Formicoxenus,  160  ;  on  Tomo- 
gnatkus,  161 

Adminicula,  327 

Aedes,  455  n. 

Aegeria,  387 

Aegeriidae,  386 

Aegialitidae,  265 

Aegocera  tripartita,  411 

Aenictus,  159,  179,  1SU 


Aenigmatias  blattoides,  495 

A  eolothrips  fasc ia (a,  528 

Aepophilidae,  559 

Aepus,  206 

Aerostatic  setae,  408 

Aerostats,  449 

Aganaidae,  408 

Agaristidae,  370,  371,  410 

Agdistes,  426 

Agdistinae,  ^26 

Agenia  carbonaria,  A.  hyalipennis,  105 

Ageronia,  354 

Aglycyderes  setifer,  298 

Aglycyderidae,  297 

Agromyzidae,  504 

Agrotis,  415  ;  A.  S2)ina,  417 

Ahuatle,  504 

Alaena,  350 

Alaopone,  179,  180 

Alar  organs — see  Wings,  Elytra,  Tegmina 

Aletia  xylinae,  416 

Aleurodes  brassicae,  592;  ^1.  immaci 

591 

Aleurodidae,  591 

Ahtcita,  4~6  ;  A.  polydactyla,  426 
Alucitidae,  371,  426 
Alula,  447 
A  mam,  205 

Amber,  Insects  in.  144,  269,  458 
Amblyopone,  180 
Amblyoponides,  132,  180 
Ambrosia,  295 
Ambryllis,  409 
Amicta  quadrangularis,  394 
Ammophila,    111  ;    A.    ajftnis,    111  ;    ..-I. 

hirsuta.  111  ;  A.  holosericea,  111 
Amphicyrtides,  242 
Amphidusis  betularia,  412,  414 
Amphiodont,  193 
Amphipneustic,  450 
Amphizoa  lecontei,  207 


604 


INDEX 


Amphizoidae,  207 

Ampulex   compressa,    114,    115;   A.  rujl- 

cornis,  115  ;  A.  sibirica,  114 
Ampulicides,  114  f.,  169 
Amycterides,  291 
Anal  armature,  328,  416 
Anal  nervures,  318 
e,  376 


Anaspini,  267 

A  a  nsp  is,  268 

Anatomy  —  see     External    Structure     and 

Internal  Anatomy 
Anchor-process,  459 
Ancient,  Lepidopteron,  435  —  see  also 

Primitive 

Ancylolominae,  425 
Andrena,  23,  25,  30,  301,  303  ;  hair  of, 

11  ;    A.    Ictbialis,  488  ;    ^1.    inyriMenea, 

23  ;  A.  ovina,  30 
Andrenidae,  20 
Andrenides,  23 
Andrenimorpha,  388 
Andrenoides,  20 
Androuonia,  331  f. 
Anergates  atratulus,  160  f. 
Angelitos,  63 

Anisopti  i-i/.i-  aescularia,  411 
Anisotoinn  riii  mi  Diomea,  222 
Anisotomidae,   .'.'.,' 
Anisotomides,  222 
Anlagen,  143 
Anobiides,  247 
Anobium,   254  ;    A,  paniceum,   247  ;     A. 

xtr!«tum,  248  ;  A.  tessellation,  248 
Anochetus  ghiliani,  174 
Anomma,  178 
Anoph  t/i  (dm  us,  205 
Anoplura,  599  f. 
Anosia    erijipim,    A.    menippe,    345  ;    A. 

ptr.n'ppiis,  307  ;  larva,  324  ;  pupa,  327 
Antennae  ;  of  Belostoma,  566  ;  of  flies,  441  ; 

of  Lamellieornia,  191  ;  of  Lepidoptera, 

307  ;  of  butterflies,  340,  341  ;  of  Sphiii- 

gidae,  380 
Antherophagus,  235 
Anthicidae,  266 
Anthid  ium,    45  ;   .-1.    befticosum,   47  ;    A. 

diiidrnni,  45  ;    A.  manicatum,   45  ;  A. 

septemdentatum,  47  ;  A.  afriijctn/n,  30 
Antkocopa,  51 
Anthocoridae,  560 
Ant/iii/ni/iif  iinijnstifrons,  A.  Irnssicae,  A. 

cana,  506 
Anthomyiidae,  506 
Anthophila,  10  f. 
Anthophora,   32,    33  ;    destroyer  of,    272, 

274  ;  A.  per  sonata,   33  ;  A.pilipes,  33  ; 

proboscis  of,  17 
Anthothrips  acitleata,  530 
Anthracides,  486 
Anthrax,  486  f.  ;  A  .  fenestralis,  489  ;  A. 

trifasciata,  44 


A  'ii  fh  re  it  usfasciatus,  241 

Anthribidae,  278,  290 

Antisquama,  448 

Antitegula,  447 

Ant-plant,  138,  139,  168 

Ants,    131  f.  ;    and    Aphidae,    590  ;    and 

caterpillars,  356 
Ants'-uest,  Insects,   200,   213,    221,    223, 

224,   225,    231,    236,   240,   548  ;   larva, 

501.  502 
Anus,  314,  320 
Aorta,  320 
Aortal  chamber,  320 
Apate  capucina,  246 
A  put  via,  418 

Apathus  ~  Psithyrus,  q.v. 
Apatidae,  246 

Apiituni  ;  larvae,  354  :  A.  iris,  344 
Apatu rides,  352 
Aphaenogaster,  164,1 65, 221  ;A.  arenarius, 

164  ;  A.  barbarus,  131, 164  ;  A.  structor 

164,  240 

Aphaniptera,  522  f. 
Aphanocephalus,  228 
A2)helocheirus,  565 
Aphidae,  581  f.  ;  and  ants.  LSI 
Aphidiides,  590 
Apliis  maidi-radids,  584 
Aphmi/iii  xiif/i'tla,  424 
Apidae,  10  f.,  20,  32 
Apioceridae,  492 
Ajiis,  53 ;  A.  adansonii,  69  ;  A.  ilmni'stica, 

68  ;  A.    dorsata,  69  ;   A.  fasciata,   A. 

ligustica,    68  ;   A.   mellifica,  65  f.  ;  feet 

of  queens   and  workers,  69  ;  ligula   of, 

16  ;  worker  and  hairs,  12 
Apoda,  402  ;  A.  testudu,  etc.,  401,  402 
Apodidae,  402 
Apoint  pallida,  nest,  83 
Aporia  cn/fni'iji,  322 
Appetite,  491 
A/i/i'i-nifi/iiii,  96 
Apferona,   393,   394;    ^-1.  crenulella,    var. 

helix,  395 
Apterous,  beetles,  187,  263  ;  females,  95, 

96,  140,  171,  174,  315,  392,  393,  407, 

413,  430,  592— see  also  Workers  ;  In- 

sei  is,   95,  96,  505,  474,  495,  496,  518, 

531,  581  ;  males,   140,   160,    161,   172, 

585,  594 
Aquatic  ;  caterpillar,  377  ;  cocoons,  280  ; 

larva,  421  f.,  425,  504  ;  pupa,  423 
Aradidae,  550 
.1  n  id  its  orientalis,  550 
Araeocerus,  290 

Arnschnia  levana,  A.prorsa,  353 
Arbelidae,  369,  396 
.1  ri'i'ina,  373 
Archiapidae,  SI,  2.2 
Archiapides,  21  f. 
Ai-ctia  caja,  308  ;  A.  villim,  410 
Arctiidae,  370,  404,  408,  410 


INDEX 


605 


A  I'ytra,  414 

A  i-<i n mi  IK,  larvae,  354  ;  A.  papkia,  audro- 
conia,  332 

Argyromoeba  sinuata,  76  ;  A.  trifasciata, 
486 

Arista,  442 

Army-worm,  416 

A rmnia  moschata,  188 

Arthropterus,  214 

Asclera  caerulea,  267 

Ascodipteron,  520 

Asemorhoptrum  lippitlum,  160 

Asilidae,  491 

Asilus,  492  ;  A.  crabroniformis,  441 

Asparagus-beetle,  281 

Aspidiotus  camellias,  592  ;  A.  nerii,  595, 
development  of,  596 

Aspidiphorus,  246 

Aspidomorpha,  pupa,  283,  284 

Association,  of  Anergates  and  Tetra- 
morium,  160  ;  of  ants  and  other  Insects 
etc.,  180  f.  ;  of  Formica  and  Formi- 
coxenus,  159  ;  of  Strongylognathus  and 
Tetramorium,  162  ;  of  Toinoynathus  and 
Leptothorax,  161 

Astata  boops,  119 

Astatides,  119 

Asteidae,  <5$^ 

Astomella  lindeni,  490 

Astynomus,  285 

Atemeles,  225  ;  and  ant,  182 

Atherieerous,  441 

Atherix,  481  ;  ^4.  t'fo's,  480 

Atho-us  rhombeits,  257 

Atractocerus,  254 

Atrophy  of  mouth  and  stomach,  310 

4tt«,  137,  164  n.,  165,  502 

Attacus,  373  ;  .i.  «<tos,  373 

Attelabides,  291 

Attini,  158,  159,  165 

Attitude,  381,  384,  385,  388,  412,  413, 
425,  429 

Atylotus  fulvus,  483 

Autocrates  aenea,  275 

Automeris,  373 

Axin,  598 

Azteca,  158 

Azygos  oviduct,  321 

Badamia  exclamationis,  365 

Barrett,  on  increase  of  melanism,  414 

Basket-worms,  393 

Bat-parasites,  521,  560 

Bataillon,  on  metamorphosis,  306 

Bates,  H.  \V.,  on  classification  of  butterflies, 

344  ;    on  homoeochromatism,  351  ;    on 

Meyacephala,  201 
Batesian  mimicry,  337,  339 
Eathyscia,  221 
Beak,  532 

Beauregard,  on  vesicating  Insects,  275 
Beaver,  Insect  on,  219,  221 


Becher,  on  mouth  of  Diptera,  441  a. 

Bed-bug,  559  ;  enemy  of,  558 

Beddard,  on  animal  coloration,  339  n. 

Bee  (i.e.  honey-bee) — see  Apis  mellifica 

Bee-louse  or  -tick,  520 

Bees,  10  f. 

Bees  born  of  carcases,  myth,  499 

Bees'  nest  beetle,  235 

Bees,  stylopised,  300,  303 

Beetles,  184  f. 

Bellesme,  on  buzzing,  19 

Belostomidae,  534,  565 

Bernbecidae,  482 

Bembecides,  119  f. 

Bemhex,  509  ;  B.  rostrata,  4,  120,  120  f.  ; 

Ji.  spinolae,  130  n. 
Benchucha  bug,  559 

/.'•  ;  ".S'KS,    218 

Berytidae,  548 

Bibio,  475,  476,  477  ;  B.  marci,  477 

Bibionidae,  475 

Birds  and  butterflies,  338 

Biscuit-weevil,  247 

Bitoma  crenata,  233 

Bittacomorpha,  473 

Black-fly,  530 

Blanchard,  on  flies  attacking  man,  517  n. 

Blepharoceridae,  464 

Blind  beetles,  205,  221,  233 

Blissus  leucopterus,  548 

Blister-beetles,  269 

Blochmann,  on  founding  new  nests,  145 

Blood-sucking,   Diptera,  457  ;  Mosquitoes, 

467 

Blood-worms,  468 
Blow-flies,  511 
Blue-bottles,  511 
Bogus  Yucca-moth,  433 
Boldophila,  luminosa,  463 
Boll-worm,  416 
Bombardier-beetles,  201 
Bombus,  53  f. ;  insect  in  nest  of,  22i  ;  fleas 

in  nests  of,   525  ;  parasite  of,  94,   497  ; 

proboscis  of,  13  f.,  14  ;   Ji.  agrorum,  54  ; 

B.  lapidarius,  54  j  B.  muscorum,  57  ;  B. 

variabilis,  60 
Bombyces,  367 
Bombycidae,  36S,  375,  406 
Bombyliidae,  485 
Bombylius  major,  488 
Bumbi/x  mori,  375  ;  B.  yamamai,  325 
Book-worm,  247 
Borboridae,  ,504 
Borborxs,  505 

Boroce.ro,  inadagascariensis,  405 
Bostrichidae,  24b' 
Bot-flies,  514 
Brachelytra,  224 
Brachycera,  441,  454 
Brachycerides,  291 
Bradiyscelides,  592,  598 
Brack  tjtarsus,  290 


6o6 


INDEX 


Braconidae,  590 

Bradypus  cuculliger,  Tineid  on,  430 

Brahmaeidae,  36S,  374 

Brain,  320  ;  cephalic  and  thoracic,  449 

Branchiae,  208,  244 

Brands,  332 

Brassolides,  349 

Brathinus,  223 

Braner,  on  Diptercms  larvae,  451  ;  ou  Oes- 

tridae,  514 
Braula  caeca,  520 
Braulidae,  520 
Breastbone,  459 
Breeze-flies,  443,  481 
Breitenbacii,  on  proboscis  of  Lepidoptera, 

311  n. 
Breithaupt,  on   proboscis   of  bee,  15  ;    ou 

deglutition  of  bees,  18 
Brenthidae,  295 
Brenthus  anchorago,  297 
Brephris  notha,  415,  416 
Brimstones,  357 
Brontes  planatus,  234 
Brown-tail  moths,  407 
Bruchidae,  276 
Bruchus  fabae  and  B.  lentis,  277,  />'.  pi*i, 

277 

Bryophila,  418 

Bnckell,  on  development  of  pattern,  335 
Buffalo-gnats,  477 
Bugong-moth,  417 
Bugonia-myth,  499 
Bull-dog  ants,  171,  173 
Bull's-horn  thorn  and  ants,  168 
Bumble  bee — see  Boinbus 
Buprestidae,  261 
Buprestis  attenuata,   supposed   larvae    of, 

262  u. 

Burgess,  ou  suction,  311 
Buruet-moths,  390 
Burrows,  of  Dasypoda,  27;  of  Halictus,  24, 

25  ;  of  Otlfinerus,  74 
Bursa  cojnilatrix,  321 
Burying-beetles,  221 
Butterflies,  341  f. 
Buzzing,  19 
Byrrhidae,  242,  255 
Hi/ frit  nn  pilnla,  242 
Bythoscopidae,  578 
Byturus,  2J/.1 

CadpJn'ses  moorei,  391 

Calandrides,  289 

Calcium  oxalate,  406 

Calii-iiri/ii*.  101  ;   C'.  h>/alinatus,  102,  106 

CaH<t<i  1'iiriiliH-Iins,  350 

Collided  !iiii-<>,  3()3  n. 

Callidulidae,  370,  400 

CaUij>]iiii'«,  448  ;  C.  erythrocephala,  C.  i-m/i- 

itnrif,  511 

CaUirhipis  </<;/Vv/</,  256 
Callomyia,  496 


Callnstom a  fascipennis,  489 

(Jaloptenus,  270  ;  C.  italicus,  489,  C.spretus, 
488,  506,  enemies  of 

Calypter,  calypterate,  448 

Calyptrate  Muscidae,  448,  504 

Camber  well  Beauty,  352 

Camel  bot-fly,  515 

Camponotides,  144 

Camponotus,  145  ;  C.  h'gniperdus,  138, 
145,  147  ;  C.  pennsylvanicus,  138,  146  ; 
C.  rvbripes,  131  ;  C.  rufipes,  137 

Camptosomes,  279,  281 

Canephorinae,  394,  395 

Cantharidae,  269  f. 

Cantharides,  270 

Capsidae,  561 

Capsus  laniarius,  539 

Carabidae,  204  f. 

Carabides,  206 

Cavaboidea,  190,  200  f. 

Carcinomris,  554 

Carder-bees,  45  f.  45 

Cardiocondyla,  161 

Cardiophorus,  258 

Carlet,    on   sting,    6  ;  on   sound-organs   of 
Cicada,  574 

('urnivora,  200 

(.'arotine,  549 

Carpenter-bees,  33 

Carpenter-worms,  395 

Carpets,  411 

Carpvcapsa  Juliana,  C.pomonella,  <.'.  yplcn- 
i/inia,  C.  saltifans,  428 

Carpophagus,  278 

Cui-fi'ria  lacca,  597 

Cams,  on  paedogeuesis,  461 

Curyoborus,  278 

Case,  281,  392,  393,  394,  417,  422,  423, 
430,  431 

Cassidides,  279,  283 

Caste-production,  142 

Castnia,  307,  309,  316,  319  ;  C.  ciati'smia, 
C.  therapon,  372 

Castniidae,  369,  371 

( 'utttvr  canadensis,  parasite  of,  219 

Catadi/sta  lemnata,  423 

Caterpillar,  322,  324,  325  ;  of  Diptera,  474 

Gatopomorphus,  221 

Cauda,  538,  588 

Cave-beetles,  205,  221 

Cebrionides,  260 

Cecirfijifa  /'.I'l'oecaria,  424 

Cecil/am  i/in  lii.i-i,  459  ;  C.  destructor,  460  ; 
C.  tritici,  460 

f'eeidomyiidae,  455  n.,  458 
Cecropia,  plant  and  ants,  158 
<  'uli'ocera,  297  n. 

Cell,  of  wing,  317,  318  ;  complete  and  in- 
complete, 116  n. 

Cells,  formation  of,  by  bees,  21,  22,  24, 
25,  28,  33,  34,  35,  46,  48,  51,  52,  54,  56, 
60  ;  earthen,  72,  106  ;  of  Coelunites,  89 


INDEX 


607 


Celyphidae,  504 

Celyphus,  505 

Cemonus  unicolor,  128 

Cephaloidae,  275 

Cephalomyia  maculata,  515 

Cephaloon,  27 5 

Cephalothorax,  465  ;  of  Stytojis-lai-va,  302 

Cephenomyia  nifibarbis,  517 

Cerambycidae,  27S,  285 

Cerambycides,  ,.V>7 

CeramiiiSj  89  ;  €'.  lusitanicus,  89 

Ceranchia,  374 

<  'i  ri//iachys,  175  n. 

Ceratina,!!,  32 

Ceratocampidae,  36S,  375 

Ceratocombidae,  559 

Ceratognathini,  194,  195 

Ceratonema,  401 

Ceratopogon,  469 ;  G.  bipunctatus,  G.  puli- 
caris,  C.  varius,  470 

Cerceris,  125  ;  C.  arenaria,  125  ;  C. 
bupresticida,  125  ;  C.  labiata,  125  ;  C'. 
tuberculata,  126 

Cercopidae,  577 

Geresa  bubalus,  C.  taurina,  577 

Cerocoma  schaefferi,  275 

Cerophytides,  260 

Ceroplastes  ceriferus,  597 

Ceroplatus  mastersi,  463 

Cerura  vinula,  383 

Cervical  sclerites,  472 

Cetonia,  ill  auts'-nests,  149  ;  (7.  Jioricola, 
200 

Cetoniides,  .79,5,  199 

Ckaerocampa,  380  ;  recte  Choerocarnpa 

Chaetophorous,  446 

Chaetotaxy,  446 

Chafers,  194  f. 

Chalcosiidae,  391,  420 

C/idlia  hockinyi,  394 

Chnlicodoma,  32,  35  ;  G.  muraria,  30,  35 
f.,  36,  254,  486  ;  G.  parietina,  G.  pyre- 
naica,  39 

Change  of  habit  in  larva,  301,  431 

Chapman,  Dr.  T.  A.,  on  Chrysis,  3  ;  on 
classification  of  pupae  of  Lepidoptera, 
367  ;  on  Hepialux,  398  ;  on  Metoecus 
paradoxus,  268  ;  ou  jiupa  of  Lepidop- 
tera, 327  n. 

Charagia,  396 

Chartergus  chartarius,  nest  of,  82,  83 

Gheilosia  chrysocoma,  439 

Cheimatobia  brumata,  414 

Gheliomyrmex,  ISO 

Chelonariides,  242 

C/ielonia,  410 

Chelostoma,  35 

Ghennium  bituberculatum,  224 

Chermes,  583,  586,  587  ;  C.  abietis,  586. 
587,  5MI 

C'heshire,  ou  proboscis  of  bee,  15 

dagger,  525 


Child,  on  sense-organ,  442 

China-marks,  421 

Chinch-bug,  548 

Ghionea  uraneoides,  474 

Chiromyzidae,  479 

Chironomidae,  468,  474 

Chironomus,  440,  468 

Chlamydes,  279 

CMorion,  110 

Chloropidae,  504 

Chlorops,  504 

Choerocarnpa  elpenor,  380 

Clioerocampiui,  381 

Cholodkovsky  on  Chermes,  586 

Choragics  sheppardi,  290 

Chorion,  322 

Chrysalis,  326,  344 

Chrysaugiuae,  423 

Chrysididae,  1  f. 

Chrysiridia  madagascariensis,  419 

Chrysis  bidentata,  3 ;  G.  ignita,  3  ;  C. 
shanghaiensis,  4 

Ghrysochus  pretiosus,  279 

Chrysocoris  grandis,  303  n. 

Chrysomelidae,  276,  278  f. 

Chrysomelides,  279 

Chrysopolomiilae,  396 

Chrysops,  482 

Cicada,  123;  C.  plebeia,  574;  (.'.  septen- 
decim,  569 

Cicadelliuae,  578 

Cicadidae,  568  f. 

Cicindela  hybrida,  202 

Cicindelidae,  201  f. 

Cicinnus,  37 S  n. 

Cilix  glaucata  =  spinula,  401 

Cimex,  560 ;  G.  lectularius,  559 

Cimicidae,  559 

Cioidae,  245 

Cis  melliei,  245 

Cistelidae,  264 

Cistus  salvifulius,  beetle-larvae  in,  282 

Cithaerias,  348 

Citheronia,  375 

Cixiides,  576 

Cixius,  575 

Clambidae,  223 

Clasper,  314 

Classification,  of  ants,  144  ;  of  bees,  20  ; 
of  butterflies,  341  ;  of  Coleoptera,  189  ; 
of  Diptera,  454  f. ;  of  Hemiptera,  543  ; 
of  Hymenopter a  Aculeate,  10;  of  Lepi- 
doptera, 339  f.  ;  of  moths,  366  f. 

Clavicornia,  1S9,  213,  265 

Claviger  testaceus,  224 

Clavigerides,  224 

Clavus,  539 

Clear-wings,  386 

Cleggs,  481 

r/,-,w,Y/.v,  400 

Cleptes,  12,  4 

Cleridae,  253 


6o8 


INDEX 


Click-beetles,  256 

Clicking  butterfly,  354 

Clidicus,  223 

Clisiocampa  neustria,  322 

Clothes-moths,  430 

Clouded-yellows,  357 

Clypeus,  307 

Clythm  in  ants' -nests,  149 

Clythrides,  '379 

<  'in-ill  it/nfiis  caesus,  209 

Cnethocampa  processioned,  376 

Coarctate  larva,  271 

Coccidae,  592  f.  ;  destroyer  of,  290 

Coccidula,  839 

Coccinellidae,  237 

Coccus  cacti,  598  ;  G.  mannifera,  597 

Cochineal  Insect,  598 

Cochliopodidae,  402  n. 

Cochlophora,  394 

Cockchafer,  198 

Cockroach,  parasite  of,  269 

Cock-tail,  225 

Cocoon,  46,  55,  66,  109,  122,  328,  347, 
373,  376,  384,  385,  391,  403,  404,  405, 
407,  419,  424,  436,  460,  462,  494  ; 
flax-seed,  460  ;  of  ants,  134  ;  aquatic, 
280,  377 

Cocytia  <l>ii-rilli!,  382 

Cocytiidae,  382 

Codling-moth,  428 

Coelioxys,  31 

Coelonites,  89  ;  C.  abbrevi.at.tis,  cells  of,  89 

'  '  .  n"iii  i/i<i  j'i  rr/i'/i  iii'n,  480 

Coenomyiidae,  479 

Coenonympha,  348 

Colaenis,  351 

Coleophora,  431 

Coleoptera,  184  f. 

Colletes,  22  ;   C.  daviesanus,  30 

Colobo2)sis,  138 

Colon,  320 

Colorado  beetle,  278 

Colour,  corresponding  with  locale,  201  ; 
and  surroundings,  337  ;  of  larva  ami 
habits,  336  ;  of  Sphingidae  larvae,  381  ; 
physiology  of  larval,  413  ;  of  cater- 
pillars and  sex,  325  ;  development  of, 
in  Hemiptera,  542  ;  of  eyes,  440 

Coluocera  formicaria,  240 

Colydiidae,  233,  234 

Col  yd  nun,  233 

Comb,  63,  64,  65,  78,  79 

Combs  and  brushes,  134 

Compound  pupa,  452 

Composmyia,  512 

Comstock,  on  nervures,  317  n. 

Conchylidae,  427 

Connexivum.  538 

Conopidae,  497,  504 

Conorhinus  sanguisuga,  559 

Copiopteryx,  373 

Copium  clavicorne,  550 


Copius,  547 

Copper  butterflies,  356 

Copricles,  195  f. 

Coprini,  19 5  n. 

Copns  hispanus,  197 

Copulatory  pouch,  320,  321 

Cordyluridae,  504 

Coreidae,  546 

Corethra,  467 

Corium,  539 

Corixa,  567 

Corixidae,  567 

Corn-leaves,  larva  on,  281 

Coronidia,  419 

Corotoca,  227 

Corticaria,  240 

Corylophidae,  228 

Corynetides,  253 

Coscinocera  hercules,  372 

Cossidae,  3G9,  395 

Cossonides,  294 

Cossus,  309  ;   C.  lic/niperda,  319 

Costal  nervure,  318 

Cotton-stainer  bug,  548 

Cotton-worm,  416 

Courtship,  494  ;  of  Hepialus,  398  f. 

Coxa,  307 

Crabro,     129  ;     C.    cephalotes,     129  ;     C. 

stirpicola,  130  n. 
Crahronides,  128  f. 
Crambidae,  425 
Crane-flies,  471 
Cratoparis,  290 
Cremaster,  327,  328,  344,  426 
Cremastochilini,  200 
Oremastochilus,  200 

Cremastogaster,  213,  165  ;  C.  tricolor,  165 
Crepitation,  213,  214 
Criocerides,  279,  280 
Criiiceris   aspcmtyi,    281  ;     C.   mcrdigera, 

281 

Crossocents,  130  ;  C.  wesmaeli,  130 
Cryptocephalides,  279 
Gryptocephalus,  ,.'.s' .' 
Cryptocerata,  544  ',  562  f. 
Cryi)toceriui,  132,  134,  158,  159,  169 
Cryptoczrus,  138  ;   C.  atratus,  170 
Cryptophagidae,  235,   .'•.,' 
Cryptophagus  di'iifuhm,  235 
Cryptostomes,  279,  282 
Cteniza  ariana,  destroyer  of,  490 
Ctenophora,  475 
Cteuostylidae,  517 
Ctenuchinae,  409 
Cuckoo-bees,  22 
Cuckoo-spit,  577 
Cucujidae,  232,  234 
Cucujos,  258 
Cuculiuae,  20 
Cidex  pipiens,  466 
Culicidae,  466  f. 
Cultelli,  443 


INDEX 


609 


Cuneus,  539,  540 
Oupesidae,  234 
Curculiouidae,  290 
Curtice,  on  Hypod&rma,  51  <> 

<  'ni'iiji/i'ii,  465 

Cut-worms,  415 

Cyathoceridae,  243 

Cybister  laterimaryincdis  or  roeseli,   210  : 

C.  tripnnctatus,  211 
Cybocephaius,  232 
Cyclica,  27 'J,  282 
Cyclorrhapha,  454  ;  C.  Aschiza,  455,  494  f. ; 

C.  Schizophora,  456,  503  f. 
<' i/l :, Iran,  253 
C'vlindrotomina,  474 
Cymatophoridae,  368,  386 
Cymbidae,  410 
t'i/iiiimi/ia  mortuorum,  510 
'  'fil/hagogus  segnipes,  296 
'  'i/ji/ii'itftt.  368  11. 
(.'yphoiiid,  clavatc.,  576 
Cyphonidae,  255 
C'yrtidae,  489 
C'yrtocorides,  545 
C'yrtocoris  monstrosus,  546 

Dacnides,  237 

Dactylopius  citri,  595 

Daddy-long-legs,  471 

Dakruma  coccidivora,  424 

Dalla  Torre,   Catalogue  of  Hymeuoptera, 

21 

Danaides,  344,  347 
Danaioid  Heliconiidae,  346 
Danais  archippus,  or  plexippus,  345 
Dances,  351,  464,  493,  554 
Darwin,  C.,  on  Pelobius,  208 
Darwin,  F.,  on  proboscis  of  Lepidoptera, 

311  n. 

Dascillidae,  243,  255 
Dascillus  cervinus,  '255 
Dosychira    pudibund", 

407 

Dasygastres,  20,  35  f. 
Dasypoda  hirtipes,  27 
Dead-leaf  butterfly,  353 
Death-watches,  248,  254 
December-moth,  406 
Deer  bot-fly,  517 
Deer-fly,  518    ' 
Delphacides,  576 
l>i'ltiii;'i>httlus  inimwus,  578 
Deltoidae,  418,  423 
Denudatae,  20,  29 
T)eporaus,  291 
J)ermatobia  noxialis,  517 
Dermestidae,  241 
Deroca,  400 

Derodontidae,  244,  253 
berodontus  macitlatus,  245 
De  Saussure,  on  wasps'  nests,  81 
Devil's  coach-horse,  225 

VOL.    VI 


408  ;     L>.    rossii, 


Dewitz,    on  development,  of   sting,  8  ;    of 

thoracic  appendages,  9 
Dexiidae,  510 
Diactor  bilincatus,  547 
Dianeura,  392 
Diateina  holymenoides,  547 
Dichoptic,  440 
Didhadia,  178,  180 
Dictyocicada,  543 

J)il<>2>hus  febrilis,  477  ;  D.  vulgaris,   17'' 
Dimera,  544 
Dimorphic,   generations,  586  ;  males,  161, 

172 

Dimorphism,  139  ;  of  wings,  549 
Dinapate  wrightii,  246 
Dingar,  70 

Dinoponera  grandis,  132.  134,  171 
iJionychopus  niveus,  410 
Diopsidae,  503,  50h  505 
Diopsis  apicalis,  503 
Dioptinae,  409 
Dioptoma  adamsi,  251 
bioscorea  batatas,  beetle-larvae  in,  280 
Dioxys  cincta,  32,  43 
Diphyllides,  237 
Diplocutes,  248 
b  iplonych  us,  566 
Diploplectron,  119 
Diploptera,  10,  71  f. 
Diplosara  lignivora,  429 
Diplosis,  459  ;  D.  resinicola,  459 
bipsocoris  alienus,  559 
Diptera,  438  f. 
Dipterous  parasitic  larva,  26 
birphia  tarquinia,  377 
Discocellular  nervures,  318 
Dismorphia,  346,  357 
Dissociation  of  embryo,  70  n. 
bixa,  471 
Dixidae,  471 

Dohrn,  Anton,  on  Hemiptera,  538 
bolichoderides,  157 
Dolichopidae,  493 
bolichopns  undv.latus,  441 
bolichurus  haemorrhous,  116 
Lonacia,  280 
Donaciides,  279 
Dorsal  vessel,  320  ;  529 — see  also  Internal 

Anatomy 
borycera,  504 
Doryceridae,  504 
Dorylides,  174  f. 
Dorylini,  175.  177 
Uorylns,    13:J,    177,    179  :    />.    helvolus, 

178 

Dwyphora  decemlineata,  278 
Dragon,  383,  385 
Drepanidae,  370,  400 
brepanosiiilin in  fi/(i/nii<ntlt"i,  f>s.> 
Drepanulidae,  400 
Drilides,  24S 
Driver  ants,  178 


6io 


INDEX 


Drones,  63,  67,  69 

Drosophilidae,  504 

Lrurya,  362 

Dryomyzidae,  504 

Dri/iiphthortis,  2S9 

Duhois,  on  luminescence,  259 

Dudgeon,  on  Badamia,  365 

Dufour,  on  host  helping  parasite,  26 

Duke  of  Burgundy  fritillary,  355 

Duration,  of  ant-colonies,  154  ;  of  wasp- 
colonies,  70  n.,  80  ;  of  life — see  Longevity 

D arrant,  on  moth-cases,  431 

Dutch  bulbs,  larva  in,  501 

Dyar,  classification  of  larvae  of  moths, 
367 

ia,  389 
s,  199 

Dynastides,  195,  199 

Dysdercus  sutvrdhis,  548 

Dytiscidae,  210  f. 

Dytiscus,  211 

Ear  las,  410 

Eau  de  Javelle,  368  n. 

Ech  innpli tli irius,  600 

Ecitun,   159,   175,  f  ;    K.    humatuin,    175, 

177 

Ecitonini,  174,  175  f. 
Ecpn itf/n '/-in,  409 

l-'.rliltinillllll     Illlflltum,     131 

Ectreplics  kituji,  248 

Edible  larvae,  287 

Egg,  305,  435,  468  ;  as  food,  504,  568  ; 
of  bot-fly,  514,  515  ;  of  Capsidae,  561  ; 
carried,  547,  551,  566  ;  of  Kmlm-lms, 
558  ;  of  Reduviidae,  559  ;  of  flea,  524  ; 
laid  by  pupa,  469  ;  of  Lepidoptera,  321, 
322  :  of  Nepa,  564  ;  numerous,  397, 
few,  197  ;  standing  out  string  of,  378  ; 
swallowed,  508 

Egg-tubes,  321 

Eggers,  322,  405 

Elaphi'I/'iK  rillnsum,  286 

Elaphomyia,,  505 

Elateridae,  256 

Elaterides,  260 

Kl  -odes,  263 

Elephn.  a to/n  i/ia,  472 

Ehnides,  244 

Elymnias,  348 

Elymniidae,  348 

Elytra,  184,  186,  539 

Embolium,  539 

Embryonic  dissociation,  70  n. 

Emenadia  flabellata,  269 

Emery  on  classification  of  ants,  144  ;  on 
polymorphism  in  ants,  143 

Emesiides,  555 

Emperor-moth,  374 

Empidae,  492,  494 

Empodium,  446 

Eniprctia  s/imulans,  403 


Eucyrtns,  34  ;  Eiicyrtus  fuscicMis,  em- 
bryology of,  70 

Eudomychidae,  237,  239 

Endotrichiinae,  4~3 

Endromidae,  369,  406 

Energopoda,  ^,57,  491 

Enhydrus,  216 

Eutomophila,  10 

Enzyme,  259 

Epeolus  variegatvs,  3C 

K/iln'xtia  kn.lt n k'lla,  306,  424 

Ephydridae,  504 

Ephyra  pendularia,  412 

Epiblemidae,  427 

Epicausis  sinithi.  409 

H/il'-li iKipteryx,  395 

Epicopeiidae,  368,  418 

Epicranium,  307 

Epicypta  scatophora.  463 

Kpidapus  scabiei,  462 

Epilachnides,  238 

Epimeron,  307 

Epinntia  funebrana.,  428  ;  E.  Jiyperii-ni/i', 
parasite  of,  476 

Epipaschiinae,  4% 3 

Epipharyngeal  sclerites,  14 

Epipharynx,  14,  308,  443,  600 

Epiplemidae,  SOS,  420 

Epipyrops,  404 

Episternum,  307 

Epitritus,  170 

Epuraea,  2-32 

Emstria  scitula,  417 

Erebia,  347  ;  E.  aetJdops,  347 

Erebides,  418 

Eremochaeta,  457 

Eremochaetous,  446 

Ereiiiocoris,  548 

Ergatandrous,  140  n. 

Ergatogynous,  140  11.,  142 

Ergatoid,  140 

Erlcerus  pela,  597 

Eriocephala,  308  ;  E.  ccdthdla,  434 

Eriocephalidae,  433 

Eriocera,  472 

Kristalis,  499 

Ermine-moths,  409 

Erotylidae,  235,  236 

Erucaeformia,  475 

Ery tides,  364 

Erycinidae,  341,  354,  358 

Erycinides,  355 

Ethon,  262 

Eucephalous  larvae,  450 

Kin-i-i-ii,  32 

Eucliaris  ni)/rmeciac,  173 

EiichJiH-  co rdamines,  egg,  322  ;  larva.  358, 
359  :  pupa,  358;  E.  yenutia,  358 

Kin-li  roma  yoliath,  261 

Kiicinetus,  256 

Eucleidae,  401 

Euclid ia  mi,  415 


INDEX 


611 


Eucnemides,  260 
Eudaemonia,  373 
Eiulamus  proteiis,  340 
Eueides,  351 
Eugereon  hocking  i,  542 
Euglossa,  34  ;  .#.  cordata,  35 
Eiignoristus  monachus,  289 
Eulema,  35 
Eulen,  414 
Eulyes,  558 
Eumaeus,  355 

Eumenes   arbustorum,    73 ;    /?.    coarctata, 
73,  74  ;  A',    conica,    74  ;   A',  flavopicta, 
72  ;    7i.    pomiformis,    72  ;    JK.    unyui- 
culuta,  73 
Eumenidae,  72  f. 
Eumolpides,  ,579 
Eumyiid  flies,  ^JG 
Euparayia,  89 
Euphoria,  200 
Euplocin,  408 
Eupluea,  345 
Eupoda,  579,  280 
Eupsalis  ininuta,  296 
Eupterotidae,  565,  376 
Eurygona,  larva,  355 
Euschemon  rafflesiae,  371 
Eusemia  villicoitles,  410 
Eusthenes  pratti,  533 
Euthyrhynehusjloridanus,  546 
Excoecaria  biglandulosa,  424 
Excrement  as  covering,   281,    283,   463— 

see  also  Adapted  excrement. 
Excremental  dwellings,  284,  379 
External  structure,  of  Aphidae,    588  ;  of 
Chrysiclidae,  2  ;  of  Coleoptera,  185  ;  of 
Diptera,  439  f.  ;  of  fleas,  523  ;  of  Hemi- 
ptera,  534  ;  of  Hepialus,  400  ;  of  Hymen- 
optera    Aculeata,    5  ;    of    Lepidoptera, 
307  f.  ;  of  Thrips,  527 
Exudation  of  fluid,  238 
Eye-collar,  387 
Eyes,  four  in  number,  215,  251,  476 

Fabre,  J.  II.,  on.  Ammophtta,  111  ;  on  An- 
thrax, 486  ;  on  Member;,  I'M  f.  ;  on 
Calicurgus,  101 ;  on  Chalicodoma,  37  f. ; 
on  Eumenes,  72  ;  on  Halictus,  24  ;  on 
Miltogramma,  509  ;  on  Osmia,  48  f.  ; 
on  Scarabaeus,  196  ;  on  Sculia,  97  f.  ; 
on  Sitaris,  272  ;  on  Sphex,  108  ;  on 
Stelis  nasuta,  30 

False  cones  of  Chermes,  587 

Families  of  moths,  key  to,  368  f. 

Feeding  young,  147 

Fertonius  luteicollis,  130 

Fever-fly,  477 

Filnria,  and  Mosquitos,  468 

Filicornia,  200 

Finding  nest,  38  f.,  126 

Finn,  on  protected  butterflies,  345  n. 

Flagella,  384,  442 


Flatides,  576 

Flax-seed  cocoon,  460 

Fleas,  522  f. 

Fly-disease,  513 

Food,  abstinence  from,  254  ;  of  bee- 
larvae,  19  ;  small  in  amount, '277 

Food-reservoir,  320 

Footmen,  409 

Forbes,  on  ant  sounds,  155 

Forel,  Aug.,  on  tropical  American  Ants, 
138  ;  on  classification  of  Ants,  144 

Forest-fly,  518 

Formica  exsectoides.  149  ;  F.  fusca.  137, 
150,  151  ;  F.  rufa,  148,  154  ;  /'.  sen- 
guinea,  149  ;  F.  schavfussi,  152 

Formicidae,  131  f. 

Formicoxenus  nitidulus,  148,  159 

Fornax,  260 

Fossil,  Ants,  143  ;  Beetles,  261  ;  Diptera, 
458  ;  Hemiptera,  542  ;  Thrips,  531  ; 
Wasps,  88 — see  also  Palaeozoic 

Fossores,  7,  10,  90  f.,  346  ;  classification, 
93, 

Fossorial  solitary  wasps — see  Fossores 

Founding  new  nests,  Ants,  145  1. 

Frenulum,  316,  318.  319,  400 

Frieclerich,  on  Parnid  larvae,  244 

Friese,  on  habits  and  classification  of  bees, 
21  ;  on  hosts  and  parasites,  30  f. 

Fritillaries,  352,  354 

Froghoppers,  577 

Frog- spit,  577 

Frontal  ganglion,  320 

Fnlgora  candelario,  575 

Fulgoridae,  543,  574  ;  larva  living  on,  404 

Fulgorina,  543 

Fumea,  393',  395 

Fungus  cultivated  by  ants,  167 

Fungus-gnats,  462 

Funnel-twister,  292 

Gad-flies,  481 

Gahan,  J.  C.,  on  Praogena,  264 
Galea,  309 
Galerucides,  379 
Galgulidae,  562 
Galleria  mdlvnella,  306,  331 
Galleriidae,  423 
Gall-midge-flies,  461 

Galls,   262,  430,  424  ;  of  Coccidae.  ;V.'s  : 
of    Aphids    and    Phylloxera,    587  ;    of 
I'syllidae,  580  ;  of  Thrips,  530 
Ganglbauer,  on  Staphylinidae,  224 
Garden-whites,  357 

Garman,  on  mouth-parts  of  ThysanopU-ra, 
528 

Gastropacha  quercifolia,  405 

Gastrophilus  equi,  515 

li'irunt,  401 

Gelechiides,  429 

Gena,  185 

!  utiuns,  306 


6  I  2 


INDEX 


Geometers,  411 

Geometridae,  36S,  411,  416,  420 

Geomyzidae,  504 

Qeoryssidae,  243 

Georyssus  pyrjmaeus,  243 

Geotrupes,  stridulation  of,  195 

Gerrides,  552 

Gerris,  535,  552 

( ill ilianella  Jilirentris,  555 

Ghost-moths,  396 

Giraffomyia,  505 

Girdlers,  286 

Glands,    321,    323,    331,    363,    399,  538, 

553  ;  accessory,   320  ;  of  Filippi,  324  ; 

mandibular,   216  ;  salivary,  326  ;  silk-, 

325  ;  stink-,  257  ;  wax-,  589 
Glaphyrini,  195  n. 
<iliij>]uii-i>]>ti-f(i  pida,  441 
Glaucopides,  339 
Glossa,  309 

Glossina  morsitans,  512,  513 
Glow-worms  ;  248  ;  New  Zealand,  363 
Glyptus,  206 
Gnats,  466,  468 
'•'i/'ijihaela,  409 
Gnostidae,  223 

Goat-moths,  395 — see  also  Cossus 
Godart  on  trumpeter-bee,  58 
Godman    and     Salvin,    on     spermathecal 

bodies,  321 
Gold-tail  moths,  407 
Gonapophyses,  9,  305 
Gonin,  on  development  of  wing,  328,  329 
Goossens,   on  legs  of  Lepidoptera  larvae, 

323 

<i<,sxiip<ii-ia.,  597 
Graber,  on  mouth  of  louse,  599 
(irapholitha  sebastianiae,  428 
Grapholithidae,  -£J7 
Grass-moths,  425 
Grayling,  347 
Green,  E.  E.,  on  classification  of  Coccidae, 

593 

Given-bottles,  511 
Green-fly,  581  f. 
Ground-beetles,  204  f. 
Ground-pearls,  592,    598 — see    also  Mar- 

garodes 

Grypocera,  341 
Guest-ant,  159 
Gula,  185 

Gymnocerata,  544,  544  f. 
Gymnodomes,  82 
Gyrinidae,  201,  215 
Gyrinus,  215 

Haase,  on  mimicry,  339  n. 

Hadrt's  Irpidotus,  482 
serrata,  512 

li'/ilm utix,  600 
482  ;     //.  2}^ivialis,     483, 
443 


Haemoglobin,  468 
Haemonia,  280  ;  H.  curtisi,  280 
Haetera,  348 
Hag-moth,  403 

Hairs,   plumose   or  feathered,   11,   12  ;    of 
Dermestid    larvae,     241  —  see  also  Setae 
Half-loopers,  415 


Halidus,    23  ;     H.    Unenlatus,    24  ;     H. 

malachurus,  23  ;  H.  maculatus,  25  ;  H. 

morio,     24  ;       H.      qvadricinctus,     22, 

25  ;   //.  ntbicundus,  26  ;  H.  sexcinctus> 

24,  269 

Haliplidae,  209 
Hcdirytus  amphibius,  474 
Halobates,  552  ;  H.  sobrinus,  551 
Halobatodes,  553 
Halteres,  438,  44S,  593 
Halticides,  278,  279 
lldiiniil  njas,  347 
Hammock-moth,  379 
Hainpson,  on  classification  of  moths,  367 

f.  ;  on  clicking  butterfly,  354  ;  on  frenu- 

lum,  316 

Hampsonia  pulcherrhna,  391 
Handlirsch,  on  Bombus,  58 
Harpactorides,  558 
Harpalides,  206 

Harpalus,  205  ;  H.  caliginosus,  185 
Harpes,  314 

Hart,  C.  A.,  on  larvae  of  Diptera,  473 
Hart,  J.  H.,  on  the  parasol-ant,  142 
Harvesting  ants,  164 
Hatchett   Jackson,    on    colour    of  larvae, 

325 

Haustellata,  366 
Haustelhun,  308 
Hawk-moths,  380  f. 
Head-vesicle,  442 
Hearing,  organs  of,  191,  313 
Heath-butterfly,  347 
Hebridae,  551 
Hebrus,  551 
ll'<;<tesia,  371 
Heerwurm,  464 
Heliconiidae,  346 
Heliconiides,  351 
Hi-lii-niiius,  346  ;  H.  erato,  H.  meipomene> 

If.  rhea,  351 
Hetiothis  armigera,  416 
HcUuodes  taprobanae,  206 
ffelochares,  218 
Hdodes,  255 
Helomyzidae,  504 
Helopdtis,  561 
Helotidae,  235 
Hemariis,  383 

'f"driiinii-t.,  493 
di/itera  haeckeli,  553 
Hemi-elytra,  539 
Hemileucidae,  374 
Humiptera,  532  f. 


INDEX 


613 


Henicocephalidae,  554 

Hepialidae,  306,  369,  396  f. 

Hepialus,  309,  310,   311,  317,    319,  322  ; 

H.  humuli  and  others,  396  f'. ;  //.  lupuli- 

nus,  397 
Heredity,  454 
Hcriades,  35 

Hermatobates  haddoni,  553 
Hermetia,  479 
Hesperiidae,  341,  342,  363 
Hessian  fly,  452,  460 
Hestia  idea,  340 
Heterocera,  340,  366,  f. 
Heteroceridae,  219,  243 
Heterogenea,  402 
Heterogeneidae,  402 
Heterogyua,  10,  131  f. 
Heterogyuidae,  369,  392 
Heterogynis,  369  n.,  392 
Heteromera,  190,  262  f. 
Heteroiieuridae,  504 
Heteronotus  trinodosus,  576 
Heteroptera,  532,  534,  535,  539,  543 
Heterotarsini,  264 
Heaxitoma  pellucens,  441 
Heylaerts,  on  Psychidae,  392 
Hibernation,  of  Vanessa,  352 
flilara,  493 
Hilbrides,  405 
Hill -ant,  see  Formica  rufa 
Hill-grub,  417 
Himantopteridae,  392 
Himera  pennaria,  411 
Hippobosca  equina,  518 
Hippoboscidae,  518 
Hippopsini,  288 
Hirmoneura  obscura,  485 
Hispa,  282 
Hispides,  279,  282 
Histeridae,  230 
Histia,  391 
Histoblasts,  453 
Histolysis,  452,  595 
Hockings,  on  stingless  bees,  63 
Hoffer,  on  Bombus,  54 
Hollandiidae,  396 
Hvlolepta,  230 
Holonietopa,  504 
Holoptic,  440 
Holoptilides,  557 
Holymenia,  547 
Hornoeochroniatism,  337,  351 
Homoeoderus  mellyi,  193 
Homomorpha,  542 
Homophysinae,  421 
Honioptera,    532,    534,    535,    543,    544  ; 

parasite  of,  303,  497 
Honey,  18,  80 
Honey-ant,  152 
Honey-bee — see  Apis  meUiJica 
Honey-dew,  580,  589,  :V.'7 
Hook-tips,  400 


Hoplopus,  74 

Horn,  G.  H.  ,  on  classification  of  Carabidae, 

206  ;  of  Silphidae,  223 
Horn,  W.,  on  classification  of  Cicindelidae, 

202  n. 

Hornet,  81,  87 
Hornet's-nest  beetle,  227 
Horns  as  food,  430 
Horse  bot-fly,  515 
Horse-flies,  481,  518 
Hot  springs,  Insects  in,  479 
House-fly,  511 
Hover-flies,  498 
Hubbardv  on    ambrosia-beetles,    295  ;    on 

Phnbetron,  403  ;  on  Xenos,  303 
Huxley,  on  Apliids,  585,589  ;  on  sclerites 

of  oesophagus,  15 
Ilybocampa  milhauseri,  385 
Hybotiuae,  492 

Hydnophytum,  139  ;  II.  montanum,  133 
Ilydrocampa  nymphaeata,  421 
Hydrocanipidae,  421 
Hydrocampiuae.  421 
Hydrocores,  562 
Hydrocorisae,  562 
Hydrocyphon  deflexicollis,  255 
Hydrometra,  552  ;  H.  stagnorum,  551 
Hydrometridae,  551 
Hydrophilidae,  216  f. 
Hydrophilides,  210 
Ht/dmjjhilus  piceus,  217 
Hydroporides,  201 
Hydroporus,  211,  212 
Hydroscaphidae,  228 
Hydrous  caraboides,  218 
Hygrobia,  208 
Hylecoetus  dermestoides,  255 
Hylcmyia  strigosa,  50(J 
Hymenitis,  346 
Hymenoptera  Aculeata,  4  f  .  ;    H.  Tubuli- 

fera,  1  f. 

Hyper-metamorphosis,  270,  488 
Hypertely,  in  Kallima,  354 
Hyphydrus,  212 
Hypnody,  489 
Hypocephalus  armatus,  288 
Hypochlorite  of  potash,  368  u. 
Hypode/mia  bovis,  H.  lineata,  515 
Hyponomeuta,  parasite  of,  70  n. 
Hypopharyngeal  sclerites,  14,  17 
Hypopharynx,  15  u.,  324,  443,  52  1,  600 
Hypopygium,  446 
Bypsidae,  370,  408 
lliipsoides  radaina,  376 
Hystrichopsylla  tatpn'  ,  523 


Tdia  fasciata,  513 

/,/,./,,////•;/«  spectrum,  527 
Iniaginal  di.-cs  or  folds, 
hulKiul  a  ;int.   158 
Individual,  ^>^'> 

associations,  338,  339 


614 


INDEX 


Infericornia,  548 

Infra-oesophageal  ganglion,  541 

Inquilines,  30,  81 

Insects  as  food,  417,  504,  568 

Instars,  of  AsjiiiUntux,  596;  of  Coccidae, 
595  ;  of  Efjiaii/fa,  271 

Instinct,  235,  274,  373,  403,  424,  487, 
546  ;  of  Ants,  590  ;  of  Bembe.c,  121  ; 
of  Clialii'.niiiiiiiit,  37  ;  of  Dasypoda,  28  ; 
of  Mdipona,  64  ;  of  Miltogramma  and 
/>'•  mbex,  509  ;  of  Odynerus,  76  ;  of 
()s,,,in,  48  f.  ;  of  Pompilus,  102;  of 
lUii/m-httes,  292  ;  of  Trigona,  64 

Internal  anatomy,  of  Diptera,  449  ;  of 
Hepialiifi,  400  ;  of  Hemiptera,  540  ;  of 
Lepidoptera,  319  f  .  ;  of  larva  of  Lepi- 
doptera,  324  ;  of  Lice,  600 

Internal  nervures,  318 

Iodine,  213 

Ipides,  232 

Ischium,  523 

Ischnogaster,  82,  88  ;  /.  mellyi,  87 

Isoderniinae,  550 

Isomera, 

Issides, 

It/n»nia,  346  ;  7.  jiusio,  346 

Ithomiides,  34(i,  351 

Ituna,  34G 

Ityraca  ni'ji-nci  ncta,  576 

Jassidae,  578 

Jiga,  or  "mimic  me,"  92 

Johnston's  organ,  442 

Jordan,  on  antennae  of  butterflies,  341  n.  ; 

on  Thysanoptera,  529  f. 
Jugatae,  366 
Juguru,  316,  400 
Jiif/urt/iia,  89 
Julodis,  262 
Jumping-beans,  428 


lima,  353 
Karbi,  63 

Kellogg,  on  Lepidopterous  structure,  307  f. 
Kentish  glory,  406 
Kermes,  597 
Knot-horns,  424 

Ktnnnrm-iii  rii'tnriusa,  99 

Koo-chah-bee,  504 

Kootchar,  63 

Koptorthosoma,  70  n. 

Korschelt,  on  formation  of  eggs  of  J\'<y«>, 

564 

Kiiuekel  d'Herculais,  oa  VvliiceUu,  501 
Kungu  cake,  467 

Laap  Insects,  581 
Labella,  443 
La/iii/ns,  llo,  176,  ISO 
Labium  of  Lepidoptera,  310 
Laboulbene,      on     sound  -production     by 
Arctiidae,  410 


Lac,  597 

Lacinia,  309 

Laciniata,  .j'JG,  434 

Lacvit  in  a r! mix,  257 

Lariisninii  cliiriiloto,  378 

Lady-birds,  237 

La.fjoa  tipcri-nlaris,  404 

Lagoidae,  404 

Lfiijrid  Ii!r1n,  264 

Lagriidae,  264 

Lake,  colour,  597 

Lamcllicornia,  190  f.  ;  enemies  of,  97 

Lamiides,  2S7,  288 

Lamprosomides,  ..'?!> 

Lampyrides,  248 

Lampyris  noctiluca,  250 

l.iiiiiii-lniidia  anqphtiiaZma,  233 

Languriides,  237 

Lantern-flies,  575 

Laparosticti,  19,5  n. 

Ln/iliria,  492 

Lapidicolous  beetles,  205 

Lappet-moth,  405 

Lnricoliit's,  253 

Larra  anathema,  117  ;  L.  jwiityil 

117 

Litrrutln,  117  ;  L.  iitodesta,  118 
Larrides,  116  f. 
Larvae,  of  beetles,  188  f.,  188  ;  of  C/tri/sis, 

3  ;  of  Dasypoda,  28  ;  of  Hymenoptera, 

7  ;  of  Lepidoptera,  323  ;  of  Sphe.f,  109 
Lasioeampidae,  369,  375,  405 
LaxiiirJii/nclnix  liiirlii,-/irn  is,  297 
/,</.s///x  a/ i, ',nis,  140  ;  founding  nest,  146  ; 

L.  fnliijiiiiisn.s,  138,  153  ;  L.  niger,  153 
Latridiidae,  240 
Lai fi<! ins  uiiiitifus,  240 
Latter,  0.,  on  Puss-moth,  384 
Leaf-cutting  ants,  165  f. 
Leaf-nests  (ants),  155 
I.i'i-n  a  i a  Hi    hesperidum,     594;    L.    oleae, 

417  ;  L.  perxicae,  597 
Ledra,  545,  57S 
Legs,  abdominal,  9 
Leisfus  sjiii/iliii i-liis,  204 
Lcma  melanopa,  281 
Lemouiidae,  354 
Leon,  on  Jli-miiliptera,  553 
Lepidoptera,    304   f.  ;    L.   Haustellata,   L. 

Laciniata,  3>i>> 
Leptalis,  346,  357 
Leptidae,  479 
Leptinidae,  220 
Leptiiiilhifi,  221 
Leptinus  testaceus.  220 
Lead's  sciiJi'jHii'i'n,  441,  481 
Leptovircus,  362 
Leptoderini,  221 

I.i-/iti'<it-niis,  171  ;  L. falcigera,    171 
Leptomastax,  223 
Leptothorax  acervomm,  161 
Lerp  Insects,  581 


INDEX 


6l5 


Leto,  397  ;  /,.  venus,  396 

Leucania  unipunctata,  416 

Leuckart,  OH  Melophagus,  519 

Leucospis,  46  ;  L:  gigas,  44 

Leutlmer,  on  Odontolubis.  193 

Libythea,  342 

Libytbeides,  355 

Lice,  599  f. 

Ligula,  16 

Limacodes,  489 

Liuiacodidae  370,  401  ;  parasite  of,  4 

Limnas  chrysippus,  345 

Limnichides,  242 

Limnobia  intermedia,  472 

Limnohihiae,  472 

Limochores  taumas,  340 

Limothrips  denticornis,  530 

Lindemann,  on  injuries  from  Thrips,  530 

Lingua,  16 

Lingula,  15 

Liometopum  microcephalum ,  158 

Lipara  lucens,  128,  451 

Liparidae,  406 

Lipimeura  brevirostris,  465 

Liponenridae,  464 

Lipuptena  cerri,  518 

Liptena,  356 

Lipteninae,  356 

Lita  solanella,  430 

Lithophilus,  239 

Lithosiidae,  408 

Lithosiinae,  409 

Ua.i-e.ia  axinus,  598 

Lobster,  383  ;  Lobster-moth,  385 

Loepa  newara,  374 

Lnhita  grandis,  549 

l.i'inaptera,  200 

Lmnechnsa,  142,  225 

Lonchaeidae,  504 

Lonchopteridae,  490 

Longevity,  33,  135,  286,  306  :  of  Cicada, 

569  ;  of  Melolontha,  198  ;  of  Scarabaeus, 

197 

Longicorns,  285 
Loopers,  411,  415 
Lorum,  14,  14,  16 
Lowne,    on    blow-fly,    449  ;     on     foot    of 

Dytiscus,  211 
Lucanidae,  193 

Lucanus  cervus,  194  ;  antenna  of,  191 
Luciferase,  Luciferine,  259 
Lucilia,   511,   512  ;    L.  caesar,  L.  macel- 

laria,  L.  sericata,  512 
Luciola,  249  ;  L.  italicu,  249 
Litdin  delegorgiiei,  373 
Luminescence,  250,  258  f.,  463,  469 
Lunula,  442 

Lutz,  on  exudation  of  Cocciuellidae,  238 
Lj/caena  baetiea,  356 
Lycaenidae,  341,  355,  356 
Lycides,  24S 
Lycm-ea,  346 


Lyctides,  246 

Lygaeidae,  548 

Lyraantriidae,  370,  406 

Lymexylon  navale,  254 

Lymexylonidae,  254 

Lyoimet,  on  anatomy  of  caterpillar,  324  n. 

Machaerota  guttigera,  578 

M'Cook,  on  honey-tub  ants,  152 

Macrocneme,  389 

Macroglossini,  380 

Macrolepidoptera,  340 

Macronychits  cjuadrituberculatus,  244 

MacTotoma,  heros,  287 

Maggot,  449 

Malachiidae,  252 

Molachius  aeneus,  252 

Malacodermidae,  248,  252,  266 

Malaxation,  110,  126 

Malpighian  tubes,  320,  334,  429,  449,  460, 

466,  473,  529,  540,  588 
Ma/millo  curtisea,  378 
Jlan — see  Manna 
Mandibles,  of  Lepidoptera,  308  ;  of  pupa, 

436,  437 

Mandibulata,  434,  536 
Manna,  597 

Manson,  on  Mosquitoes,  468 
Manticora  maxttlosa,  203  ;  M.  tuberculata, 

202 

Marane,  377 
Marbled-white,  347 
Marchal,  on  embryonic  dissociation,  70  n.  ; 

on  Ammophila,  111  ;  on  pigments,  334 
Margarodes,  595,  597,  598  ;  M.  vitis,  598 
Marimbonda  da  casa,  118 
Maruina,  471 
Masaridae,  88  f. 

Masaris,  89  ;  M.  vespiformis,  88,  89 
Mason -bee,    35   f. — see    Chalicodoma  ;    of 

New  Zealand,  107 
Mastiyus,  223 
Matthews,  on   Hydroscaphidae  and   C'ory- 

lophidae,  228  ;  on  Sphaeriidae,  227 
Maxillae,  of  Lepidoptera,  309 
Mayer,  Paul,  on  Hemiptera,  536 
Meadow-brown,  34~ 
Meal-worm,  263,  264 
Mealy-bugs,  592 
Mechanitidae,  346 
Medeterus  ambiguus,  493 
Median  nervure,  318 
Mcgacephala,  201 
Megachile,  35,  51  ;    M.  albocincta,  ."••_'.  ;"". ; 

J/.  anthracina,  52  ;  M.  fasciculata,  '•-  : 

M.  lanata,  53  ;  M.  proximo,,  53 
Megalopides,  279,  282 
Megalopygidae,  404 
3[eg<di/kns  grai-ilis.  490 
Jfei/aitostoma,  543 
Megarrhina,  4  1.",  |i>7 
Megascelides, 


6i6 


INDEX 


Megasoma,  199 
Megathymus,  371 

Megistorhynchus  longirostris,  485 

Meijere,  on  stigmata,  450 

Meinert,  on  Anoplura,  600  ;   on  mouth  of 

Diptera,  444  ;  on  paedogcnesis,  461 ;  on 

Stylops,  302 
Melandryidae,  265 
Melanism,  414 
Afelanitis,  351 

Melanophila  decostigma,  261 
Melecta,  31,  33  ;  AI.  luctuosa,  31 
Mi  lihoeus,  larva,  355 
Melirjethes,  232 
Mi'/inaea,  351 

Melipona,  53,  62  ;  M.  acuMlaris,  64 
Melitaea,  larvae,  354 
Melliiera,  10 
Melliiitts,  123  ;  M.  arvensis,  123,  124  ;  M. 

sabulosus,  124 
Meloe,  33,  274 
Meloidae,  269 
Meloides,  270 

Alelolontha  vulgaris,  194,  198 
Melolonthides,  195,  198 
Mflnphayus  ovinus,  518,  519 
Melophorus  inflatus,  153 
Melyridae,  252 
Membracidae,  576,  578 
Alewbracis  foliata,  577  n. 
Membrane,  of  Hemiptera,  539 
Menorhynchous,  542 
Merodon  equestris,  501 
Merrifield,  temperature  experiments,  337 
Mesodont,  193 
Mesophragma,  312,  445 
Mesoscutellum,  312 
Mesoscutum,  311 
Mesosternum,  307 
Mesovelia,  551 
Mesozoic  beetles,  261 
Messor,  164 
Metamorpha,  351 
Metamorphosis,  529  ;  of  Aleurodidae,  591; 

of  Cicada,  571  ;  of  Coccidae,  594  f.  ;  of 

Diptera,  452  ;  of  Hemiptera,  542 
Metapneustic,  450 
Metascutellum,  313 
Alethoca  ichneumonides,  96 
Metochy,  183 
Aletoeciis  paradoxes,  268 
Meyrick,     classification     of     Lepidoptera, 

367 

Miastor,  461 

Mice,  insects  in  nests  of,  221 
Alteration,  501,  502 

Microlepidoptera,  340,  427  :  trophi,  309 
Micropezidae,  504 
Microphysides,  560 
Microptera,  234 
Micropterism,  549 
Micropterygidae,  369,  435 


Micrr>ptenj.v,    307   f.,   317,   319,   327,  433 

435,  436 
Midge,  461,  470 
Migration,  Aphis-,  585 
Mik,  on  Hilara,  493 
Milichiidae,  504 
Miltogramnia,  508,  121 
Miinacraea,  356 
Mi  mesa  bicnlor,  128 
Mimesides,  127 

Mimicry,  337  f. — see  also  Resemblance 
Mines,  Dipteron  in,  474 
Miscqphus,  116 
Models,  346 
Moesa-blight,  561,  562 
Mollusca,    eaten    by   beetle -larvae,    252  ; 

larvae  mistaken  for,  501 — see  also  Snails 
Jlolosstts,  parasite  of,  560 
Monarch-butterfly,  345 
Monda  rhabdophora,  393 
Monema  fla/oescens,  4 
Moniez,  on  fertilisation  of  Coccidae,  594 
Monodontomerus  nitidus,  44 
Monohammus  confustis,  286 
Mouomera,  544 
Monommidae,  265 

Monomorium,  560;  M.  pharaonis,  163 
Monotoniides,  240 
Minittwmifi  ilimidiata,  nest  of,  83 
Mi>r<leUa,  268 
Mordellidae,  267 
Morddlistena  floridensis,  268 
Mimnolyce,  205 
Mormolycides,  206 
Morphides,  348 
Morpho,  315,  331,  349  ;  M.  menelaus,  318  : 

M.  achillvK,  M.  epistrophis,  larvae  of,  349 
Mosquito,  466  f. 
Mosquito-bees,  61 
Mosquito-blight,  562 
Moth-flies,  470 
Moths,  366  f. 
Motuca  fly,  482,  122 
Mouth,   absence   of,    310,   443,    489,   514, 

515,  585,  596 
Mouth-parts,  of  Diptera,  442  f.  ;  of  fleas, 

523  ;  of  Hemiptera,   534,  535  ;    of  Hy- 

menoptera  Aculeata,  13  ;  of  Lepidoptera, 

307  f.  ;  of  Lice,  599,  600 
Mud-dauber,  113 
Miiggenbnrg,  on  Melophagus,  518 
M  tiller,   Fritz,   on  Imbauba-ant,    158  ;    on 

Trigona,  64 

Miiller,  H.,  on  Dasypoda  liirtipes,  27 
Miiller,    W.,    on   South  American    larvae, 

344  n. 

Miillerian  mimicry,  339 
Mundstachel,  527,  528 
Murray,  A.,  on  Lice,  601 
Musc<t  ifii/iii-f<fica,  511 
Muscidae,   511   f.,   517  ;  M.  Acalyptratae, 

503  f.  ;  M.  Calyptratae,  448,  504 


INDEX 


6I7 


Musotiinidae.  423 

Mustiliidae,  376 

Mutilla,  94,  95  ;  M.  europaea,  94 

Mutillides,  94  f. 

Mycetaea  hirta,  239,  240 

Mycetaeidae,  239 

Mycetobia  paUipes,  462,  463 

M  vcetophagidae,  237 

Mycetophilidae,  462 

Mydaidae,  491 

Mygnimia,  105 

Myiasis,  512 

My iatrojin  florea,  499 

Myiodocha  tipulina,  557 

Myoditini,  267 

Myopinae,  497,  498 

Myrapetra,  82 

Myrmedd,  171,  172,  173 

Myrm-ecocystus  hortideorum,  152  ;  M.  mel- 

liger,  152  ;  J7.  mexicanus,  152 
Myrmecodia,  139 
Myrmeeophilous  Insects,  181  f. 
Myrmedonia,  226 
Myrmica  laevinodis,  148  ;  M.  rubra,  133  ; 

M.  rubra,  races  ruginodis,  scabrinodis, 

163 

Myrmicides,  158 
Myrmicini,  159 

Nabides,  556 

Nabis  lativentris,  556 

Nacerdes  melanura,  266 

Xaclia  ancilla,  390 

Nagana,  513 

Nagel,  on  digestion  by  injection,  212 

Nagoda  nigricans,  401 

Nanosella  fungi,  228 

Nassouoff,  on  Strepsiptera,  301  n.,  302 

Naucoridae,  565 

^Vecrobia  ruficollis,  253 

Neorophorus,  221 

Nectar,  18 

Helens  interruptus,  antenna,  191 

Nematobola  orthotricha,  431 

Neniatodes,  in  Thysanoptera,  530 

Nematois  metallicus,  32 1 

Nenieobiides,  355 

Nemedbius  lucina,  335,  355 

Xemestrina,  455  n. 

Netnestrinidae,  484 

Neniocera,    440  ;    N.   Anoniala    N.    Vera 

456 

Nemognatha,  304 
Nemosomides,  233 
Neocastniidae,  372 
Neolepidoptera,  366 
Neotropidae,  346 
Nepa,  541  ;  ^V.  cinerea,  563 
Nepidae,  544,  563 
Xepticula,  431 

Nervous  system,  Coleoptera,  191 
Nervules,  319,  429 


Nervnration,  of   Diptera,    447  ;.    n(   Lepi- 

doptera,  317  f. 
Nervures,  318  ,  319  ;  development  of,  329 

f.  ;  swollen,  347,  348  ;  of  Eumenes,  73 
Nests,  of  ants,  136  f.,  155;  of  Formica  fused 

a.w\S»leno2)sisfuyax,\Z1 ;  ofPorphyras- 

pis,  284  ;  of  wasps,  79  f.  79,  81.  83,  87 
Netrocera,  341  u- 
NeuroblastSj  453 

Newbigiiij  Miss,  on  pigments,  334 
Newport,  on  Meloe,  270 
Nicagini,  195 
Nicolas,  on  Halictus,  24 
Nilionidae,  265 
Nitidula,  232 
Nitidulidae,  231, 235 
Noctuidae,  311,  370,  410,  411,  414  f. 
Node,  131,  134 
Nolinae,  409 
Nolidae,  410 
Xomada,    30  ;    JV.   lathburiana     30  ;    »V. 

sexfasciata,  30 
Nonne,  407 
Nopal  cactus,  598 
Nosodendrides,  21$ 
Notocyrtus,  558 
Notodonlidae,  305,  368,  383 
Notodontina,  J+11 
Notonectidae,  567 
Number    of  species:    of   Apidae,    10  ;  of 

Butterflies,  343  ;  of  Coccidae,   593  ;  of 

Coleoptera,     184  ;    of    Diptera,     438  ; 

of    Fleas,    525  ;    of   Hemiptera,    543  : 

of  Lepidoptera,   306  ;  of  Lice,  600  ;  of 

Thrips,  527 
Nun,  407 
Nurses,  66,  134 
Xydalemon,  419 
Nyctemeridae,  409 
Nycteolinae,  410 
Nycteribia,  521,  522 
Nycteribiidae,  521 

Nymph,  of  Cicada,  569  ;  of  Thrips,  529 
Nympha  inclusa,  452 
Nymplialidae,  .'541,  343  f. 
Nymphalides,  351 
Nyinphipara,  518 

NympJuda  stayiiata,  N.  siratiotata,  423 
Nyssonides,  123 

Oak-Pruner,  286 

Obtusilingues,  20 

Oceanic  bugs,  552 

Ocelli,  325  :  0.  compositi,  325 

Ochthiphilidae,  504 

Ocneria,  407  n.  ;   O.  dispar,  408 

Ocnerodes,  489 

Ocnogyna,  409 

Ocf/pits  olens,  225 

Odontolabis  ni>i>:it.-<is,  193 

Odontoniachi,  171,  17-'! 

Odour,  of  bugs,  541 


6i8 


INDEX 


Odynerus,    74   f.,    269  ;    0.  antilope,    75  ; 
0.    i-ii/lnsus,    76  ;    0.  parietvin,    3  ;    »• 
jin  ii<-tii  ni,    77  ;     0.  reniformis,  73,   75  ; 
0.  spinipes,   3,  76 
OeciK-i'i-is  i/ni/i'iti-lla,  430 
Oecodoma,  l:J7, 164,165  ;  Oe.cephalotes,133 
Qecophylla  swir/ /•"(/<///<«,  147 
Oecophoridae,  429 
Oedeagus,  314  [recte  aecleagus] 
Oedematopoda  2>ri>iceps,  387 
Oedemeridae,  266 
Oestriclae,  514 
Oestrus  uris,  517 
Ogcodes,  489,  490 
Oil-beetles,  269 
<l/n»/>/ii/i>  r-tliirnm,  430 
Olethreutidae,  ^7 
Olibms  bicolor,  231 
Oligarces,  461 
Oligonephrous,  542 
Oligoneura,   4tJl 
Ommatophorinae,  414 
Oiii-iiti'i-i-s.  286 
o//, •//,/,  496 

<>/,/,;,/,  res  t  nUnnica,  311 
Opomyzidae,  5f.£ 
<>/>"steya,  429 

i  image-tip,  357 — see  also  Euchloe 
Orectui-Ji  Hi'*.  216 
o/v/,<  hyalodisca,  400 
Origin  of  parasitic  bees,  32 
Orneodidae,  340,  371,  426 
Oi-iiithoptera,  360  ;   0.  bronkiana,  362  ;  0. 

/Hiradisea,  360,  361,  362 
Orplniepliilidae,  470 
Ortalidae, 
Ortalis,  447 
Orthogenya, 
Orthezia,  5±l,  598 
st  206 

nfi'i/H'i-ii's,  0.  brunnipes,  228 
Orthoptera,  555  ;  parasite  of,  497 
Orthorrhapha,  454  ;  0.  Brachycera,  478  f . ; 

0.  Nemocera,  455,  458  f. 
Ori/fti's  ,insi,-fi,-iiis,  199 
Oscinidae,  ,504 
Osmeterium,  363 

Os/nii/,  47,  48  f. ;  enemy  of,  100  ;  liair  of, 
11:  <>.  ri/iniii,'-'infha,'32;  0.  lei'i'm/n/" ii'<. 
29;  0.  iriciirnis,  48  ;  0.  tridentata,  4.8  f. 
Osten     Saoken     on     Bugonia,     499  ;     on 
Chaetotaxy,    446  ;    on   classification    of 
Diptera,      456  ;     summary     of     Port- 
schiusky,  512 
Othniidae,  265 
Otiorhynchides,  437 
Ounii-iii'iiiis,  355,  356 
Ovaries,  541,  602:  in  larva,  325 
Oviduct,  320,  321 
Oviposition,  of  Cicada,  571 ;  of  Ifbtonecta, 

567  :  "I1  Tin-In  an,  507 
Ovipositor.  436,  506,  531,  539 


ou-l.-t-moths,  414 
Ox-warbles,  517 
O.ajbelus,  129 
Oxychirotinae,  425 
Ozaenides,  214 

I'lu.-lii/pvs,  187 

Packard,     on    Hymenopterous    metamor- 
phosis, 7 

Pad,  of  Lepidoptera,  314 
Paedogenesis,  303,  461 
Pagiopoda,  544 
Palaeolepidoptera,  366 
I'liJi/eomicra,  435 
Palaeotropinae,  347 
Palaeozoic  Insects,  311,  542 
Palmer-worm,  323 
Palpicornia,  310 
Paltostoma,  465 
1'iilnstra,  377 
PdH'jKiiin  liiiii/ii-nsfi-.'s,  482 
Panomoea,  237 
Panurgides.  .'" 
/'nfiifin.  359  ;  P.  aja.i:,  forms  of,  335  ;  P. 

Kiifi-iniii'/iiif!,  362  ;  P.  zalmoxis   3.. 
Papilionidae,  342~  357,  359 
Paracelyphus,  505 
Paragia,  89 

Parallel  series  iu  Aphidae,  ."s.") 
/'urandra,  288 
Parapompilus  gravesii,  105 
Paraponera  clavata,  172 
Parnjii'iiii.'-.  423 
Paraptera,  312 

Parasites,  among  ants,  183  ;  of  mason- 
bee,  43  ;  of  larva  of  Andrena,  26  ;  of 
Oih/iii-i-ns,  76 

Parasitic,  bees,  23,  29  f.  ;  Prosopi.!,  32  ; 
Diptera,  507 

Parasyscia,  175  n. 

Parmn.ta,  501 

Parnassitis,  .:}.',  362 

Parnidae,  919,  243,  355 

Piirniijii-s  carnea,  4 

Parnus,  244 

Parthenogenesis,  24,  85,  86.  395,  430,  469, 
530,  583,  594 

Parthenogenetic  young,  139  n. 

Passalidae,  192;  larva,  192.   .'';: 

Passcdoecus,  128 

Patagia.  311,  312 

Pattern,  formation  of,  335 

Patula,  414 

Paurometabola,  542 

Paussidae,  101.  213 

/',/iissns  ci'/iliiilntes,  etc.,  214 

Pai-nniu,  350 

Pea-weevil,  277 

Peacock  butterfly,  352 

Peal,  on  sound-producing  ant,  156 

Peckham,  on  Fossores,  130  n.  :  on  in- 
stinct, 70,  99 


INDEX 


6  19 


Pectinicornia,  /.''/ 

Pedicinus,  600 
Pediculidae,  599 

Pediculus  (.ii/iitix.  599,  601  ;  ./'.  mrlittae, 
274  ;  P.  vextuiieitti,  601 

Pedilidae,  £££ 

Peduncle,  133,  134 

Pegomyia  inunis,  79 

Pelobiidae,  207 

Pelobius  tardus,  208 

Pelogonidae,  562 

Pelopaeus,  110,  112  n.  ;  P.  bilineatus, 
114;  P.  laetus,  113,  117;  P.  madra- 
spatanus,  113  ;  P.  spirifex,  112 

Peltasticta,  245 

Peltides,  233 

Pemphigus,  589 

Pempliredon  higubris,  128 

Pemphredouides,  127 

Penis,  314 

Pentamera,  790 

Peutanephria,  466 

Pentatoma,  541  ;  P.  rujipes,  535 

Pentatomidae,  533,  545,  5^6' 

Pepsis,  104,  389  ;  P.formosus,  105 

Perez,  on  bee-parasitism,  32  ;  onHalictus,  24 

Pericoma  canescens,  470 

Pericopinae,  409 

Peridrepana,  401 

Peril  it  us,  282 

Peripneustic,  450 

Peritracheal  spaces,  332,  333 

Perkins,  R.  C.  L. ,  on  bee  and  acarid  sym- 
biosis, 70  ;  on  Odynerus,  76  ;  on  Prusujiix, 
21 

Perophora  batesi,  P.  melsheimeri,  377  ;  P. 
sanyuinolenta,  379 

Perophoridae,  377 

Perothopides,  260 

Peytoureau,  on  ninrjiliology  of  abdoium, 
313,  314 

Pliaeism,  337 

Phalaeridae,  231 

Phalacrocera  replicata,  474 

Phaloniadae,  4^7 

Plianaeus  splendidulus,  antenna  of,  191 

Pharynx,  320 

Pliaudinae,  392 

Pheidole,  165 

Pheidologetoii  laboriosus,  159  ;  /'.  diversus, 
167 

Phenax,  575 

Phengodes  hieronymi,  249 

Phengodini,  251 

Philaenus  spumaritis,  577 

Philanthides,  124  f. 

Philanthus  upivo-nts,  127  ;  P.  trianyulum, 
125 

Phileurus  didymus,  antenna,  191 

Philonthus  nitidua,  225 

Phlebotomus,  470 

Phhiea  curticatu.  545 


Pldoeides,  545 

Phloeothrips  frwnentariits,  530 

Phtibetron  pithecium,  403 

Phonapate,  246 

Phoridae,  494 

Phosphae.nus  hemipterus,  249 

Phosphorescence,    250  —  see    also    Lumin- 

escence 

Pliragma,  307,  313 
Phragmocyttares,  81 
Phthanocoris,  543 
Phthiriasis.  601 
Phthirius  inguinalis,  601 
Phycitidae,  424 
Phycodromidae,  504 
Phyllocnistis,  431 
Phyllomorpha  laciniata,  547,  548 
Phyllm-kina,  parasite  of,  520 
Phylloxera,  587 
Phylogeuy  of  butterflies,  343  n. 
Pliymatidae,  554 
Phyjnatopus,  399 
Physapoda  or  Physopoda,  531 
Phytomyzidae,  504 
Phytophaga,  190,  237,  276  f. 
Phytophthires,  544 
Phytoscopic  effects,  336 
Pierella,  348 
Pieridae,  341,  357 
Pierisbrassicae,  340  ;  development  of  wing, 

328,  329.  333 
Piesma,  550 
Pigments,  330,  334,  357 
PiTifer,  308 
Pill-beetles,  242 
Pinaridae,  405 
Piophilidae,  504 
Pipnnculidae,  496 
Pijmnculits,  496 

/V.V'H,    118 

Pit-falls,  481 
Playiolepis  trimeni,  153 
Playithmysus,  287 
Plant-lice,  581  f. 
Plants  and  ants,  183 
Plataspides,  545 
Platycnema,  496 
Platypezidae,  496 
Platyphora  Ivbhnfki,  495 
Platypides,  289,  295 
Platypsyllidae,  219 
Platypsyllus  castoris,  219 
Platysoma  depresftnni,  230 
Platystomidae,  504 
Plea  wiitutissiMUi  567 
Pliny,  on  Mason-bee,  44 
Ploiaria  pullida,  556 
Plume-  moths,  426 
Plumules,  331 
Plus  in,  415 


Podili"_rid;ir.  32 


62O 


INDEX 


Poecilocampa  popvll,  406 

Poecilocapsus  lineal  us,  542 

Poecilocyttares,  81 

Pogonomyrmex  barbaius,  1C4 

Pogonosloma,  203 

Poison,  of  Hymenoptera,  7  f. 

Poison-glands,  2 

Poisonous  caterpillars,  376,  403,  404,  405 

Polisles,  86  ;  P.  and  Stylojjs,  301,  303 

Pollen-gathering  and  -carrying,  11,  12 

I'nl, ,>,;,,,  nests  of,  81,  82,  S3 

Polyclenes  fumarius,  560 

Polyctenidae,  560 

Polyergus  lucidus,  151  ;  P.  rufescens,  150  f. 

Polymorpha  (Coleoptera),  189,  190,  213  f. 

Polymorphism,  139  f.,  143 

Polyphyllafullo,  antenna,  191 

I'nlnplom,  386 

Polyplocidae,  386 

Polyplocoles,  248 

Poli/i-/i<ii'//is,   155  ;  P.  pandurns.  156  ;  P. 

spinigera,  138 
Pompilidae,  93,  101  f. 
Pouijiiltis,    103;    P.  polisloides,   104;    I'. 

sericeus,  106 
Pont- i-<i  conlracla, P. ergalandria,  P.puncta- 

tiHxiinit,    17'- 

Ponerides,  132,  170  f. 

Porpliyraspis  tristis,  284 

Porphyrophora  polonica,  597 

Porriirlifiin-lniH,  216 

Portsehinsky,  on  habits  and  development  of 

Muscidae.  507,  512 
Post-metamorphic  growth,  141 
Post-scutellum,  307,  312 
Polamorjeton  peclinaltis,  beetle  on,  280 
PolamqphHus  acuiniitnlus,  244 
Potassium  hydroxide,  328,  384 
Potato-beetle,  278 
Pouch,  abdominal,  350,  362 
Poulton,  on  colours,  339,  336 
Praecostal  nervures,  319 
Praescutum,  312 
Pratt,  on  iinagiual  discs,  453  n.  ;  on  Melo- 

phagi/.s,  519 
Pi-i'/iniiii,  larva,  354 
Prey,  of  Fossores,  table,  92 
/'/•/I/  dulcamarae,  232 
Primitive,  beetles,  251,  252  ;  Diptera,  475 
I'rincnemis  ajfiitis,  5  ;  P.  bicolor,  107 
Priodont,  193 
Prionides,  287 
Proboscis,  13,  14,  16,   17,  304,  307,    309, 

311,  443,  482,  485,  532 
Processional  maggots,  464 
Processionary  caterpillars,  376,  408 
Prodoxidae,  432  ;  mouth,  309 
Prodoxus,  433 
Pro-legs,  323 
Politic,     Aphids,     589  ;     Coccids,     594  ; 

Hepialus,  397  ;  Lice,  601  :   .1/-7,,,,  274  ; 

Slylops,  301 


Prominents,  383 

Pronuba,  321  ;  P.  yuccasella,  432  ;  P.  syn- 

Ihetica,  432 
Pronymph,  453 
Propodeum,  131,  133 
Propolis,  63 
Propygidium,  187 
Pmsofiis,  21,  22  ;  hair  of,    11  :  proboscis 

of,  17  ;  P.  signala,  21 
Protection,    43,    413  ;    of   trees   by   ants, 

158  ;  of  plant  by  ants,  168 
Proterhinidae,  298 
Prolerhinus  leconlei,  298 
Protolepidoptera,  336 
Proloparce  Carolina,  309 
Prolopaussus,  214 
Psammorycler  vermileo,  481 
Pselaphidae,  223  ;  and  ants,  182 
Psen  atratus,  P.  concolor,  127 
Psephenus,  244 
Pseudholoptic,  440  n. 
Pseudocorylophidae,  228 
Pseudodicthadia,  180  ;  P.  incerta,  177 
lii/n/lus,  431 
graeca,  99 
I'seudomorphides,  206,  205 
Pseudomyrma  bicolor,  168 
Pseudomyrinini,  168 
Pseudoueuroptera,  527 
Pseudopaedogenesis,  303 
Pseudopod,  188,  264,  267,  290,  449,  492 
Pseudoponlia  paradoxa,  357 
Pseudo-pupa,  271,  273 
Pseudotetramera,  190 
Pseudotrimera,  239 
Pseudovespa,  88 

Pseudovarium  and  Pseudovum,  584 
Pseudovitellus,  588 
Psilidae,  .504 
Psiliylossa,  larva,  8 
I'siliii^'jilnitu,  484 
Psilurn  monacha,  407 
Psifhyrus,  53,  57,   59  f.  ;    P.  campestris, 

60  ';  P.  veslalis,  60 
Psocidae,  248 
Psyche  helix,  394 
Psychidae,  369,  392 
Psychina,  394,  395,  404 
Psychmia,  466 
Psychodidae,  470 
Psylta  puricola,  579,  580  ;    P.  snccincla, 

579  ;  P.  buxi,  580 
Psyllidae,  578 
Plerocheilus,  76 
Pterotli'ctn.   100 

Pterophoridae,  371,  425,  340,  426 
Pterophorinae,  426 
Plerustichus,  205 
Pterothysanidae,  369,  406 
Pterygodes,  312 
Pterygogenea,  542 
Ptilimim,  442,  503,  520 


INDEX 


621 


Ptilinn.s  jn  ctinicomis,  250 

Ptilocnemus  sidnicus,  557 

Ptilomacra,  395 

Ptilomera  laticaudata,  553 

Ptinidae,  246 

Ptomaphila  lacrymosa,  222 

Ptycln'iiti'i'ii,  466 

Ptychopteriuae,  47- 

Ptyelv.s  goudoti,  577 

Pugs,  411 

Pulex  avivm,  P.  irritans,  P.  serraticeps, 
525  ;  P.  obtusiceps,  525 

Pulicidae,  522  f. 

Pulii-ijiliiii-ii  lucifera,  495 

Pulvillus,  446 

Pupa,  of  beetles,  188  f.  ;  coarctata,  452  ; 
obtecta,  227,  327,  451  ;  depositing 
eggs,  469  ;  hairy,  407,  426  ;  of  Lepi- 
doptera,  326  f.  ;  with  mandibles,  436 

Pupurium,  452 

Pupation,  ofBadamia,  365  ;  of  Parnassius 
and  Thais,  363 

Pupipara,  456,  513,  517 

Purple  emperor,  344 

Pusci,  504 

Puss-moth,  328,  383,  406 

Pygidium,  187 

Pyralidae,  340,  370,  420 

Pyralidina,  420,  426 

Pyrameis  atalanta,  353  ;  P.  cardvi,  353  ; 
P.  tammeamea,  353 

Pyraustidae,  421 

Pyroctvroa  rubens,  266 

Pyrochroidae,  266 

Pyrophorus,  258  ;  P.  noctilucus,  259 

Pyrrliocoridae,  549 

Pyrrkocoris  apterus,  535,  549 

Pyrrhopyge,  364 

Pythidae,  265 

Pytho  depressus,  266 

Quartenia,  89 

Queen,  66,  67,  69,  140 

Races,  of  Apis,  68 

Radial  nervures,  319 

Raffray,  on  Poyonostoma,  204  ;  on  classi- 
fication of  Paussidae,  214  ;  on  classifica- 
tion of  Pselaphidae,  224 

Railway-beetle,  251 

Raiiatra  linearis,  563 

Raptorial  legs,  493,  554,  556 

Reaumur,  on  Xylticnpa,  33 

Receptaculum  semiuis,  140 

Rectal  cauda,  538 

Red  admiral,  352 

Red  ant — see  Formica  rufa 

Reduviidae,  555  f.  537 

Reduvius  personatns,  558 

Regimbart,  ou  Gyriuidae,  216 

Resemblance,  between  ant,  wasp,  and 
spider,  169;  between  Antii"/>li«r<i  and 


Bombus,  33;  between  Ar<-ti<i 
and  Eusemia  villicoides,  410  ;  between 
beetle-larva  and  Termite,  206  ;  between 
Biimhus  and  Eulema,  35;  between  Bom- 
byliidae  and  Hymenoptera,  489;  bei  v 
bug  and  ant,  556,  557  ;  bug  and  Tipulid. 
556,  558  ;  bug  and  fly,  547  ;  iu  b' 
flies,  348  ;  between  Callidulidae  and 
Lycaenidae,  400  ;  between  Celyphus  and 
llemiptera,  505  ;  between  Cleridae  and 
insects  they  destroy,  254  ;  between 
Dioptinae  and  Ithomiides,  409  ;  between 
Diptera  and  Hymenoptera,  499,  500; 
between  Jfyicopeia  and  Papilio,  418  ; 
between  Flatides  and  Lepidopteiu,  57'!  : 
of  flies  and  bees,  502  ;  to  galls,  403  ; 
between  host  and  parasite-bees,  30  ; 
between  Insects  of  different  Orders,  339  : 
of  Ithomiides  to  other  butterflies.  :;i>;  ; 
between  lady-bird  andEudomychid,  '2-'~  : 
of  larva  to  a  colony  of  larvae,  418  ; 
of  larva  of  Odynenis  and  of  Chrysis,  4  ; 
between  larvae,  162  ;  in  Liniacodi<l:i.\ 
401;  of  Lobster  caterpillar,  385  ;  between 
Longicorns  and  Hymenoptera,  287  ; 
of  moth  to  bird-excrement,  401  ;  of 
parasite  and  prey,  95  ;  of  Pericopina.eand 
Heliconiid.es,  409  ;  between  prof< 
butterflies,  345  ;  between  J'sithi//-/'*. 
Bombus,  59  ;  of  Reduviid  and  P>  / 
558;  between  Rhyphus-  and  M >/< •••/,, /,,'./- 
larvae,  463  ;  of  Syntomids  to  other 
Insects,  388  f.  ;  of  Tipulids  and  Hymen- 
optera, 475  ;  between  two  kinds  of 
ants,  162 

Resting-larva,  306 

Retinaculum,  316,  319,  420 

Retort-shaped  bodies,  in  mouth  of  II    . 
ptera,  535 

Reuter,  E.,  on  classification  of  buttt-rtlio. 
343  n. 

Rhachicerus,  480 

JUiagoi'elia  plumbed,  552 

Rhaphiorhynchus,  483 

RhegmatophUa  alpina,  3C5,  386 

Rlicumatobates  beryrothi.  553 

Rhinomacerides,  291 

Jihinopsis,  115  ;  R.  ruficornis,  169 

•  Rhinosimus,  266 

Rhipicera  mystacina,  25C 

Rliipiceridae,  256 

Rhipidiini,  267 

Rh ipidii.iptcra,  543 

Rhipiphoridae,  '_'i;7 

Rhipiphorides,  '2>'^ 

Hhipiptrra.  _'.ls  fin  i  rvr  for  Khiphij •• 

Rhiz( 

Rlli^iifl-i'i/nx,     I'.'l 

/.'      :'      ura, 
l!li'  "imiK.  17'.'. 

340,  84] 

206 


622 


INDEX 


Rhopalomeridae,  504 

liln.jiillnxnmfl  pOeiji,    100 

Rhopalosomides,  1UH 

Rhygchiuni  brunneum,  /?.  furiiiitt^cni,  li. 

nitidulum,  R.  oculatt/m,  77 
Hhtinchites  betv.lac,  291,  292 
Rhyiichitides.  291 
Rhyuchophora,  19<>,  277,  288  f. 
Rhynchophorous  series,  240 
Rliiliu-liojixi/Un  i/nJex,  526 
Rhynchota,  532 
Rhyphidae,  478 
Itioi/ihtis,  463 
Rhysodidae,  201,  234 
Riley,  on  A)//<v/,//,/.  270.  271  :  on  sperma- 

thecal    bodies,    321  ;    on    Yucca-moth, 

432 

Ripidius  pectin icorn is,  209 
Rippe,  of  Schaffer,  334 
Rohber-flies,  491 
Rose-chafers,  200 
Rosema,  401 
Rostrum,  291,  472 
Rothney,   on   Ampulex,    115  ;     oil    Stum, 

169  ;  on  Sphex,  110 
Rothschild,  N.  C.,  on  morphology  of  fleas, 

523  n. 
Royal  jelly,  66 

Ro-.itfx  !/"i<:/i//t'ji]t<>i-i/,  167 
Ruby-wasps,  1  f. 
I ; nrales,  342 
Rutelides,  195,  198 

Saccoderes,  .".."^  :  X.  fufn'rcn/ddts,  537 

Saccus,  314 

Siii/ 1 -a  n/ili  in//, tn,  279 

Sagrides,  ,'TJ 

So  1*1  a,  560 

Saldidae,  544,  562 

Salivary,  duct,  320  ;  gland,  320 

Sand-flea,  525  ;  -flies,  477 

Saperda  populnea,  285,  286 

Sapromyzidae,  504 

^"lnJ[l"  guinquepunctata,  100 

Sapygides,  99 

,•<« n-iiplirir/a,  510  ;  »*?.  carnaria,  510 

Sarcophagidae,  510 

Sarcophila  magnified,  S.  wohLfalvrti,  510 

Xnri-iijitit/ltt  iiiillunn-i'ii.  >'.  jii'/tetrans,  525 

Sarginae,  479 

H,   32 

ijiHx,  410 

Sasaki,  on  parasite  of  silkworm,  508 
Saturnia,  307,  310  ;  S:  pm-oni".  313,  374 
Saturniidae,  3GS,  372 
Satyrides,  347 
rfauba,  or  Sauva,  ant,  137 
Saunders,  E.,   on  feathered  hairs,    11  ;  mi 

proboscis  of  bees,  1 6 
Saunders,  Sir  S.,  on  Hymenopterous  larvae, 

8 
Scale,    131,   133,  315,   4*.; 7  :    development 


of,   329    f.  :    -formation,   333  ;    -holder, 

331 
Scale-Insects,  592  f.  ;  enemy  of,  356,  357, 

417,  425,  430 
Scalpella,  443 
Scape,  441 
Scaphidiidae,  229 
Scaphisoma  («j<iri<-inum,  229 
Scaphium,  314 
Scapulae,  312 
Scarabaeidae,  194  f. 
Scarabaeini,  196 
Scarabaeus  sacer,  196,  1S7 
Scatomyzidae,  504 
Scatophagidae,  504 
Scatopse,  477 

Si'i'lijilirini,  112  ;   fi.  iiigi-ipfs,  91 
Scenopinidae,  484 
Schaffer,    on   structure   of  wings   and  ner- 

vures,  330 
Schiodte,  on  Auoplura,  599  f.  ;  on  Hemi- 

1  >t era,  543 

Schistocerca  peregrina,  enemy  of,  506,  514 
Si-/ii-.'ii'itrjinx  iniiii/audi,  220 
Schizometopa,  504 
Schizoneura,  589 
Schizophora,  455 

Schmidt-Schwedt,  on  Donacia,  280 
Schoenbergia,  360.  361 
Schoenobiinae,  425 
Sciapteron,  387 
Sciara  militaris,  464 
Sciomyzidae,  504 
Sciophila  I'/tii/u/i-i'/i/fi/,  462 
Scolia  bifasciatc,  S.  haemorrhoidalis,  97 
Scoliidae,  93,  94  f. 
Scoliides,  97  f. 
Scolytidae,  294 
Scopariidae,  A21 
Scopariinae,  4--1 
Scope/odes,  401 
Scopulipedes,  20,  32  f. 
Screw- worm,  512 
Scudder,  on  butterflies,  543 
Scutata  or  Scutati,  54$ 
Scutellerides,  545 
Scutellige/a,  501 
Scutelhim,  307,  312,  537 
Scutum,  307  ;  S.  proboscidis,  443 
Scydmaenidae,  223 
Scymnites,  238 
Scymnus  minimus,  238 
Seasonal  dimorphism  or  variation,  335 
Seitz,  on  Syntomid  resemblances,  388,  389 
Semi-loopers,  415 
Seminal  duct,  321 
Semi-pupa,  271 

Semper,  on  development  of  wing,  333 
Sense-organ.    442,    448  ;    thoracico-abdo- 

initial,  414  ;  in  Urauiidae,  419 
Sepsidae,  504 
1    Sericaria  mo/i,  375 


INDEX 


623 


Sericteria,  325 
Seroot-fly,  482 
S.-rricornia,  189,  213,  255 
Sesia,  387  ;  S.  scoliaeformis,  321 
Sesiidae,  386,  388,  370  (for  Syntomidae), 

389 

Setae,  534  f.  ;  aerostatic,  408 
Setinu,  410 

Srvriiteen-year  Cicada,  569 
Sex,    differences,   92,   95  ;    production    of, 

32,  67  ;  in  larva,  325 
Sexuparous,  586 
Sharp,  on  classification  of  Dytiscidae,  213  n. 
Sheep,  bot-fly,  517  ;  -tick,  518 
Shield,  592 
Shoulder,  -lappets,  312  ;    -tufts,   312  ;    of 

wing,  319,  316 
Siayona,  206 
Siculodidae,  423 
Siebold,  von,  on  Strepsiptera,  301 

Sir/ara  minutissima,  568 

Sight,  of  Pompilus,  104 

Silk-glands,  325 

Silkworm,  375  ;  affected  by  parasitic  fly, 
507,  508  ;•  Madagascar-,  405 

Silpha,  221  ;  Siljjha  atrata,  S.  laevigata, 
S.  lapponica,  222  ;  S.  obscura,  222  ;  S. 
opaca,  S.  tJwracica,  222 

Silphidae,  221  f.,  252,  256 

Sima,  168  ;  S.  leviceps,  stridulating  organ, 
169  ;  S.  rwfmiiyra,  169 

Simnliidae,  477 

Simulium  colmnbaczense,  477 

Sinodendron  cylindricmn,  194 

Siphon,  563,  581,  589 

Siphonaptera,  522  f. 

Siphonophora,  239 

Siplninculata,  600 

Kitaris,  33  ;  S.  humeralis,  272 

Sitodrepa,  247 

Skippers,  363 

Slave-making  ant,  149,  150,  163 

Sloth,  430 

Slug-worms,  402 

Smallest  Insect,  228 

Smerinthini,  380 

Smerinthus  populi,  309,  381 

Smith,  F.,  on  Mellinus  arvensis,  123 

Snails,  enemies  of,  205,  222,  510  ;  parasite 
of,  495 

Social,  bees,  35  ;  wasps,  78,  84 

fc'ociales,  20,  53  f. 

Snlmnim  dulcamara,  beetle  on,  232 

Soldiers,  132 

Snldit-r-ant,  150 

liu,  395,  430 
,  nopsisfugax,  137 

Solitary  wasps — see  Fossores  and  Eunie- 
nidae 

Song,  of  Cicada,  572 

Kin-unit!,  232 

Sound-organs,  448  ;  of  Ayeronia,  354  ;  of 


Hecatesia,  371  ;  of  Cicada,  573,  574— 
see  also  stridulating  organs 
Sound-production,  155,  156  ;  by  Aegocera, 
411  ;  by  Arctiidae,  410  ;  by  Sphingidat, 
382 — see  also  Stridulation 
Spalacopsiui,  288 
Spatula,  459 

Spencer,  Herbert,  on  "VVeismaun,  143 
Spercheus  emaryinatus,  218,  219 
Spermatheca,  320,  321 
Spermophila,  506 
Sphaeridiides,  219 
Sphaeriidae,  227 
Sphaerites,  223 
Sphaeritides,  229 
Sphaerius  acaroides,  227 
Sphaerocarides,  279 
Sph.ec ia,  387 
Sphecius  speciosiis,  123 
Sphecodes,  21,  22  ;  S.  yibbus,  23,  23  ;  A 

rttbicundus,  22  ;  S.  subquadratus,  23 
Sphegidae,  93,  107  f. 
Spliegides,  107  f. 

Sphex  coendeus,  110  ;  S.  Jiavijwnnis,  108  ; 
S.  lobatus,  110;  S.  maxillosus,  108 

Sphindidae.  245 

Sphingidae,  309,  315,  316,  368,  380  f. 

Sphinx  ligustri,  380 

Spider  parasite,  490 

Spilosoma,  408 

Spinneret,  324,  325,  403,  417 

Spirachtha,  227 

Spiracles,  188,  191  ;  of  Diptera,  449  f.  ; 
of  Hippoboscidae,  519  ;  of  Lepidoptera, 
313,  314  ;  of  Lipara,  451  ;  of  Xepa, 
564  ;  of  Thrips,  528 

Spondyliaspis,  581 

Spondylidae,  288 

Springing  plant-lice,  579 

Spuler,  on  nervures,  317  n. 

Squama,  448 

Squeakers,  209 

Staetherinia,  401 

Stag-beetles,  193 

Stalk,  317,  319 

Staphylinidae,  223,  224  f. 

Staudiuger,  Schatz  and  Eober,  on  butter- 
flies, 343  n. 

Stauronotus  maroccanus,  489 

Stauropus  fayi,  385 

Stel'is  minuta,  29  ;  S.  nasuta,  30,  43  ;  & 
signata,  30 

Stelocyttares,  81 

Stenamma  ivestwoodi,  159 

Stenojateryx  hirnndinis,  519 

Stephostethus,  240 

Sternorhyncha,  544 

Sterrhopteryx,  394 

Stethopathidae,  496 

Stigmata — see  Spiracles 

Stigmatomma,  ISO 

Stigmus  pendtdus,  128 


624 


INDEX 


Sting,   4,   5,   6,   58,    144  ;  development  of, 

8,  9 
Stinging,    98  ;    by    Calicurgus,    102  ;    by 

Pompilidae,  104  ;  by  Sphex,  109 
Stingless  bees,  61 

Stink-gland,  257,  533  ;  -vessel,  225 
Stipes,  309 
Stizinae,  123 
Stomach,  320 
Stomoxys  calcitrans,  512 
Stratiomyidae,  478 
Strafivinys,  452 

Straus -Durckheim,  on  Melolontha,  198 
Strawberries,  eaten  by  beetles,  205 
Streblidae,  521 
Strepsiptera,  189,  298  f. 
Streptop&ras,  401 
Stridulating  organ,  of  Mynnica,  133  ;  of 

Heterocerus,    243  ;    of    Passalus  •  larva, 

192  ;  of  Sima  leviceps,  169 
Stridulation,  of  auts,  134  ;  of  Corixa,  568  ; 

of  Criocerides,  281  :  of  Dynastides,  199; 

of  Geotrupes,   195  ;  of  Ipides,  232  ;  of 

Lomaptera,  200  ;  of  Longicorns,  287  ;  of 

larva  of  Lucanus  cervus,  194  ;  of  Mega- 

lopides,  282  ;  of  Melolontha-\a,TV&,  1 98  ; 

of  Mutilla,   94  ;    of  Pelobius,  208  ;    of 

Phonapate,  246  ;  of  Phyllomorpha,  548  ; 

of  Prangena,  264  ;  of  Sioyona,  206  ;  of 

Trox,  195 
Strigil,  568 

Striphnopterygidae,  376 
Strongylognathus  Jixberi,  S.  testaceus,  162 
Strumigenys,  170 
Style,  442 
Stylopidae,  298 
Stylopised  bees,  26 
Stylops  dalii,  299 
Styx  infernalis,  358,  340 
Suana,  405 
Subcostal  nervure,  318 
Submedian  nervure,  318 
Siiboesophageal  ganglion,  320 
Sucking-stomach,  311,  449 
Suction  by  Lepidoptera,  311 
Suctoria,  526 
Supericornia,  546 
Swallow-flies,  519 
Swarming  of  wasps.  70  n. 
Swarms, '  62,   65    67,   80,   135,  467,  505, 

584 

Swift- moths,  396 
Symbiosis,    of  ants    and  plants,    139  ;    of 

bee    and    Acarid,    70.     See   also  Aiits'- 

nest  Insects,  and  Association 
Xi/iitfiins  blattaruin,  269 
Symphily,  183 
Synecthry,  183 
Syneinon,  371 

cyanea,  nest,  82 
ivestwoodi,  229 
Syuteliidae,  229 


Syutomidae,  339  n.,  369,  388 
Syntomis  phegea,  390 
Syringe,  535,  536 
Syrphidae,  439,  498  f. 
Systoechus  oreas,  489 
Systropus  crudelis,  489 

Tabanidae,  481,  492 

Tabanus,  482 

Tachinidae,  507,  514 

Tachysphex  panzeri,  117 

Tachytes,    116  ;    destroyer    of,    275  :     T 

australis,  113,  117  ;  T.  2>cctinipes,  117 
Tachytides,  116 
Tacnia,  fleas  as  hosts  of,  526 
Tajuria  diaeus,  pupa,  357 
Taleporia,  395 
Taleporiidae,  430 
Tanypezidae,  504 
Taphroderides,  296 
Tapinoma  fi-rn.ticum,  157 
Tarantula-killer   105 
Torphius,  233 
Tarsolepis,  383 

Taschenberg,  on  anatomy  of  flea,  523  n. 
Tuscina,  372 
Tea-plant  bug,  562 
Team  melanostictu,  408 
Tegula,  71,  187,  307,  311,  312,  447 
Tcgmina,  539 
Teleodont,  193 
Telephorides,  248 
T<-/,i,<it<ii>liili(s,  235 
Temnochila  coerulea,  232 
Tenmochilides,  233 
Tenebrio  molitor,  263 
Tenebrionidae,  263 
Tenebroides  mauriiauica,  232 
Tentacle,  maxillary,  309,  432 
Tenthredinidae,  parasite  of,  4 
Terebrantia,  531 
Tmnites,  203,  206,  227,  231 
Terrifying  attitude,  384 
Tesseratoniides,  546 

Testes,  321,  324,  400,  429  ;  in  larva,  325 
Tetanocera  ferruginea,  504 
Tetauoceridae.  504 
Tt't ragona,  53,  61 
Tetramera,  190 

Ti'tramorium  caespituvi,  160,  163 
Tettigometrides,  567 
Teucriicm,  bug  and  galls  on,  550 
Tlinlx,  pupation  of,  363 
Th, minis,  342  ;  T.  tayes,  androconia,  332 
Therevidae,  484 
Thiridopteryx,  420 
Thomas,  on  androcouia,  331 
Thorictidae,  236 
Thorictus,  236 
Thrips,     526    f.  ;    Thrips    lini,    531  :     T. 

secalino,  530 
Throscides,  260 


INDEX 


62 


Thy  (it  ifii  I  in  tin,  T.  derasa,  386 

Thymaridae,  392 

Thyimides,  96 

Thyreophoridae,  504 

Thyrididae,  370,  404 

Thyri<l<'iit>'/'ii.i:  ephemeraeformis,  394 

Thysanoptera,  526  1'. 

Tiger-beetles,  201  f. 

Tiger-moths,  409 

/'///, <x  .'/mi.ii'tus,  253,  254 

Tinacgeriidae,  370,  387 

Tinea,   305  ;  T.  pellioneUa,  429,  430  ;  T. 

nisfrlla,  430  ;   T.  vivipara,  430 
Tineidae,  340,  370,  394,  437,  428 
Tineodidae,  423 
Tlnfola  Uselliella,  430 
Tingidae,  549 
TijuiJa  brobdignagia,  475 
Tipulidae,  471  f.;  T.  Brevipalpi,  472,  473  ; 

T.  Lougipalpi,  472,  475 
Tipuliuae,  475 

ias  serra,  241 
giganteus,  287 
,  346 
Tomicides,  295 
Tmiiiignathus  sublaevis,  161 
Tongue,  309 

Tortoise-shell  butterflies,  352 
Tortricidae,  340,  395,  427,  432 
Tortricina,  395 
Toxorrhina,  472 
Toxotrypana,  506 
Trechus,  205 
Trichiiui,  200 
Trichocera,  473 
Trichodes  alvearius,  T.  ammins,  T.  apiarius, 

254 

Trichvphaga  tapetsella,  430 
Tridioptera,  306,  425 ->' 
Trichopterygidae,  227 
Trich i ipferyx  fasc ic ular is,  227 
Trichroism,  351 
Trichterwickler,  294 
Trichura,  389,  390 
Trictenotomidae,  275 
Triecphora,  543 
Trigona,    .',.!,  >!1  ;    T.  carbonaria,   G:',  :    T. 

r;v/.«///rx,  65  ;  T.  mosquito,   62 
Triinera,  23S,  544 
Tn  ni'-riii,  89 
Trineura  aterrima,  494 
Tri«iH.ti'n  inns,  489 
Triirji  rliamni,  580 
Trijilnti.'iKt,  415 
7V//V/ A  y-x,  530 
Tritoma  bipwstulata,  236 
Triunguliu,  262,  268,  270,  271,  272,   299. 

300 

Trochalopoda,  543,  544 
TriM-haiitt-i-.  307  ;  divided,  123 
Troi-li ilium,  387 
ini.  195 

VOL.   VI 


Trogositidae,  232,  235 

Trogosita,  mauritanica,  232 

Tromoptera,  457 

Trojihi  —  see  Mouth  -parts 

Trox,  stridulation,  195 

Truffle-beetle,  222 

Trumpeter  bumble-bee,  58 

Triipanueus,  230 

Trypanidae,  395 

Trypetidae,  504,  506 

Trypoxylonides,  118 

Trypoxylon,    1-18  ;    T.  albitarse,  118  ;   T. 

figulus,  119 
Tse-tse  fly,  512,  513 
Tubulifera,  1  f. 
Tubulifera  (Thrips),  531 
Tulip-tree,  tubes  on,  578 
Turkey-gnats,  477 
Turnip-flea,  278 
!         r,  or  Tussore,  silk,  374 
Tympanoterpes  gigas,  572 
T>ii,l,liiit<i,  179,  180 

178,  179,  180 


Ugimyia  sericariae,  507 

Ulidiidae,  504 

Ulopa,  578 

Uncus,  314 

Urania  rhiphens,  419 

Qraniidae,  368,  419 

Uric  acid  pigments,  357 

Urodon,  278 

Uzel,  on  Thysanoptera,  527 


:'•."•  2  ;     larva,    354  —  see    also 
and  Araschnia 

Vanessula,  35  •> 

Vapourer-moths,  407 

Variation,  of  Anomma  burmeisteri,  179  ; 
of  Bomlixs,  58  ;  of  larvae,  336  ;  of 
Sphecodes,  23  ;  of  male  and  worker 
ants,  160  ;  of  workers  and  females, 
162;  due  to  parasites,  26;  of  larva 
and  imago.  408  ;  generic,  401  ;  local, 
398  ;  in  nervuration,  414  ;  and  dimor- 
phism iu  Geometrid-larvae,  412  ;  of 
mandibles  of  Lucanidae,  193  ;  in  colour 
of  Psyllidae,  579  ;  trichroism  of  hind 
wings,  351  ;  in  size  of  Brenthidae,  297  ; 
of  time  and  form  in  Cicada,  570  ;  in 
wings,  540  ;  as  to  winged  or  wingless, 
531  ;  change  in.  414  ;  seasonal,  335 

Vasa  deferentia,  321 

Veils,  493 

Veins  —  see  nervures 

Velia  currens,  552 

Vflleius  dilatatus,  227 

Verhoeff,   on  Agenia,    106  ;  on  Halictus, 
25  ;  on    Siphonophora,  239  ;    on  > 
minuta,  29  ;   on  terminal   segments  of 
beetles,  186 

Vermileo  degeeri,  481 

2  s 


626 


INDEX 


la  alakurt,  523,  526 
Yerson,  on  rudiments  of  wings,  328 
Vertebrates,  larvae  of  Diptera,  attacking, 

506,   510,    512,   514,    514.    517,    520; 

tick-fleas  on,  526 
Vespa,  nests  of,  79,  83  ;    T".  austriaca,  81, 

88  ;    T'.  crabro,  81  ;    I',  germanica,    79 
Yespidae,  78 
Viviparous,   Aphids.   583  ;  fly,   506,   511, 

513,  518  f.  ;  moths,  430  ;  Staphylinidae, 

227 
Voice  —  see  Song,  Sound-organs,  Stridula- 

tion 
\'<>lt/cella,  500  ;    J".  fnimliyicux,  441 


Wagner,  on  morphology  of  fleas,  523  n.  ; 

on  paedogenesis,  460 
Walker,  J.  J.,  on  II(/l»bates,  552 
Wallace,  on  flight  of  Hesperiidae,  364 
Walsingham,  Lord,  on  Tortricidae,  427 
Walter,   on    mouth   of   Lepidoptera,   308, 

310      , 

Wandering  ants,  175  f. 
Wanzenspritze,  536 
Wasmann,  on  Auts'-nest  Insects,   181  n., 

183  ;    on    Lmneclmsa,    142,     226  ;    on 

Weismaim,  143 
Wasps,  71  f. 

Wasps'-nest,  beetle,  235  ;  Insect,  268 
Water-scorpion,  563 
Wax,  65,  575,  576,  597 
Wax-glands,  589 
Wax-hairs,  580 

Wedde,  on  mouth  of  Hemiptera.  535 
Weeping-trees,  577 
Weevil,  biscuit-,  247  ;  pea-,  277 
Weinland,  on  halteres,  448 
Wet-  and  dry-season  forms,  336 
Whirligig-beetle,  21  5 
White  wax,  576,  597 
Whittell,  on  Pelopaeus  and  Larrada,  117 
Wielowiejski,  on  luminous  organs,  250 
Wing-cases,  of  beetles,  186,  270 


Wing,    of   bugs,    539  :    of   Diptera,   447  ; 

of  Lepidoptera,  315  f.  ;  development  of, 

328  ;  structure  of,  329 
Wingless  —  see  Apterous 
Wingless  and  winged  Aphids,  584 
Wing-nervures—  see  Nervures 
Wing-rib,  330,  333 
Wing-veins  —  see  Nervures 
Winter-gnats,  473 
Winter-moth,  414 
Winter-mother,  586 
Wire-worm,  258 
Wood-ant  —  see  Formica  rufa 
Wood-leopard  moth,  309,  395 
Woodpecker,  Diptera  in,  506 
Workers,  54,  66,  67,  79,  85,  132,  140 
Worm-eaten  furniture,  248 

Xantharpyia  straminea,  parasite  of,  521. 

522 

Xenon,  303  :  A".  roKsii,  299.  301 
Xestobium,  24$ 
Xit/iiro/H',  -'j'2,  34,  70  ;  suluuentimi  of,  14  ; 

X.  cliliirii/tii  /•".  34  :   A",  violacea,  33 
Xylodiplnsis,  458,  459 
Xylophagidae,  479 
Xylophaginae,  480 
Xylophilidae,  266 
Xylotrupes  gideon,  199 

Yellow-fever-fly,  464 
Yolinus,  558 
Young  carried,  556 
Yucca-moth,  432 


x,  205 


ii.  566 


296 

Zeuzera  aesculi,  309,  395 
Zenzeridae,  395 

Zygaenidae,  369,  388,  390,  392,  394 
Zygia,  253 


END    OF    VOL,    VI 


Printed  by  R.  &  R.  CLARK,  LIMITED,  Edinburgh. 


THE   CAMBRIDGE   NATURAL   HISTORY. 

LIST  OF  THE  SERIES. 

To  be  completed  in  Tun  Volumes.      Svo.      \~>A.  net  each. 

VOLUME  I 

Protozoa,   MARCUS  HARTOG,  M.A.,  D.Sc.,   Trinity  College  (Professor  of  Xat 
History  in  the  Queen's  College,  Cork)  ;  Sponges,  "W.  J.  SOLLAS,  Sc.D.,  F.I 
St.  John's  College  (Professor  of  Geology  in  the  University  of  Oxford;  ;  Jelly 
fish,  Sea-Anemones,  etc.,  S.  J.   HICKSON,  M.A.,   F.R.S.,  Downing  Coll-u. 
(Beyer  Professor  of  Zoology  in  The  Owens  College,   Manchester)  ;  Star-fish. 
Sea-Urchins,   etc.,   E.  W.   MACBRIDE,   M.A.,   St.   John's  College   (Professor 
of  Zoology,  McGill  University,  Montreal). 

VOLUME  II 

Flat  Worms,  etc.,  F.  W.  GAMBLE,  M.Sc.  Viet.  (Demonstrator  and  Assistant- 
Lecturer  in  Zoology  in  The  Owens  College,  Manchester)  ;  Nemertines,  Miss  L. 
SHELDON,  Newnham  College  ;  Thread-worms,  etc.,  A.  E.  SHIPLEY,  M.A., 
Christ's  College  ;  Rotifers,  etc.,  MARCUS  HARTOG,  M.A.,  Trinity  College, 
D.Sc.  Lond.,  (Professor  of  Natural  History  in  the  Queen's  College,  Cork  : 
Polychaet  Worms,  W.  B.  BENHAM,  D.Sc.  Lond.,  F.R.S.,  Hon.  M.A.  Oxon.. 
(Professor  of  Biology  in  the  University  of  Otago) ;  Earth-worms  and  Leeches. 
F.  E.  BEDDARD,  M.A.  Oxon.,  F.R.S.  (Prosector  to  the  Zoological  Soci'  ; 
Gephyrea,  A.  E.  SHIPLEY,  M.A.,  Christ's  College  ;  Polyzoa,  S.  F.  HARMER, 
Sc.D.,  F.R.S. ,  King's  College.  [Ready. 

VOLUME  III 

Molluscs,  Rev.  A.  H.  COOKE,  M.A.,  King's  College  ;  Brachiopods  (Recent),  A.  E. 
SHIPLEY,  M.A.,  Christ's  College;  Brachiopods  (Fossil),  F.  R.  C.  REED,  M.A. . 
Trinity  College.  [Ready. 

VOLUME  IV 

Spiders,  Mites,  etc.,C.  WARBURTON,  M.  A.,  Christ's  College  (Zoologist  to  the  Royal 
Agricultural  Society);  Scorpions,  Trilobites,  etc.,  M.  LAURIE,  B.A.,  KinV- 
College,  D.Sc.  Edinb.  (Professor  of  Zoology  in  St.  Mungo's  College,  Glasgow); 
Pycnogonids,  etc.,  D'ARCY  "W.  THOMPSON,  C.B.,  M.A.,  Trinity  College 
(Professor  of  Zoology  in  University  College,  Dundee)  ;  Crustacea,  W.  F.  R. 
WELDON,  M.A.,  F.R.S.,  St.  John's  College  (Linacre  Professor  of  Comparative 
Anatomy  in  the  University  of  Oxford). 

VOLUME  V 

Peripatus,  A.  SEDGWICK,  M.A.,  F.R.S.,  Trinity  College;  Centipedes,  etc.,  F.  G. 
SINCLAIR,  M.A.,  Trinity  College  ;  Insects,  Part  I.,  D.  SHARP,  M.A.,  F.R.S. 

[/.'• 
VOLUME  VI 

Insects,  Part  II.,  D.  SHARP,  M.A.,  F.R.S.  [Rea 

VOLUME  VII 

Balanoglossus,  etc.,  S.  F.  HARMER,  Sc.D.,  F.R.S.,  King's  College  ;  Ascidians 
and  Amphioxus,  W.  A.  HERDMAN,  D.Sc.  Lond.,  F.R.S.  (Professor  of  Natural 
History  in  University  College,  Liverpool)  ;  Fishes,  T.  W.  BRIDGE,  Sc.D., 
Trinity  College  (Professor  of  Zoology  in  Birmingham  University),  and  G.  A. 
BOULENGER,  F.R.S.  [Inthel' 

VOLUME  VIII 
Amphibia  and  Reptiles,  H.  GADOW,  M.A.,  F.R.S.,  King's  College. 

VOLUME  IX 
Birds,  A.  H.  EVANS,  M.A.,  Clare  College. 

VOLUME  X 
Mammals.    F.   E.  BEDDARD,   M.A.    Oxou.,    F.R.S.   (Prosector   to   the   7. 

[!'<•  the  J 

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