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BOUGHT WITH THE INCOME OF THE
THE GIFT OF
HENRY W. SAGE
Cornell University
Library
The original of this book is in
the Cornell University Library.
There are no known copyright restrictions in
the United States on the use of the text.
http://www.archive.org/details/cu31924004082289
The house or typhoid fly, Musca domestica. Greatly enlarged. (Howard and Pierce,
photo by Dovener.)
S A N ITA RY
ENTOMOLOGY
THE ENTOMOLOGY OF DISEASE,
HYGIENE AND SANITATION
EDITED BY
WILLIAM DWIGHT PIERCE, Pu.D.
Consulting Entomologist, formerly Entomologist Southern Field Crop
Insect Investigations United States Department
of Agriculture, Bureau of Entomology
WI wea
¢\f ARTI AVERTATIN
BOSTON
RICHARD G. BADGER
THE GORHAM PRESS
CORNREL
UNIVER GIDDY
as
LIE RAR Y
Copyricat, 1921, py Ricnarp G. BapGER
All Rights Reserved
Made in the United States of America
The Gorham Press, Boston, U.S. A.
TO
Dr. LELAND OSSIAN HOWARD
CHIEF OF THE BUREAU OF ENTOMOLOGY,
THIS BOOK IS
DEDICATED
TO HIM, MORE THAN TO ANY ONE ELSE, DO ENTOMOLOGISTS OWE
THE PRACTICAL DEVELOPMENT OF THEIR SCIENCE, WHICH
TOUCHES UPON EVERY HUMAN ACTIVITY. HE STOOD AMONG
THE FIRST TO EMPHASIZE THE IMPORTANCE OF SANITARY
ENTOMOLOGY. HE STANDS NOW THE CHIEF EXPONENT OF
ENTOMOLOGY THROUGHOUT THE WORLD.
FOREWORD
In May, 1918, a class was formed among the entomologists of the
country to study the recent developments in the entomology of disease,
hygiene, and sanitation, for the purpose of equipping themselves for any
special service which they might be called upon to render during the war.
The lectures were mimeographed week by week and mailed to the enrolled
membership, which numbered in excess of 500.
The war emergency is over and the mimeographed lectures have
practically all been distributed. These lectures, however, dealt as much
with domestic as with military problems, and they have now been com-
pletely revised up to date of March 1, 1919, and are given forth as'a
series of lectures dealing with the entomological problems of peace times
from the standpoint primarily of municipal, industrial, and household
problems, and also with the hope that the course will be of assistance to
teachers, and will: stimulate research among investigators. Many
important topics have been omitted, for we cannot hope to present the
whole subject in a book of this size.
This phase of entomology is one which is destined to become very
important as our knowledge of disease transmission increases. There
are many unworked and insufficiently worked problems now in sight, and
these lectures will be found to suggest numerous possible lines of research.
I wish at this time to express my appreciation of the services of
Mr. Jacob Kotinsky, who served as Secretary of the Class, and of my
collaborators in this course of lectures.
As nearly as possible the International Rules of Nomenclature are
followed, but in Entomology the practice had not been followed of en-
closing the original author’s name in parenthesis followed by the name
of the author responsible for the present combination, and it has been
impossible in the present volume to obtain all of the necessary information,
W. Dwicut Pierce.
CONTENTS
CHAPTER PAGE
JT. How Insects Can Carry or Cause Disease. . . ea a 19
CuassiFIcaTION oF MetuHops sy Waic# Insects Can Cunt or Cause
DIsfasSE. . . ws ap (ah 20
Way It Is Nacewane: TO row Hoy Tassos Game Dicenes nive jx 1388
II. Some Necessary Steps 1n Any Arrempt to Prove Insect TRANSMISSION OR
Causation oF DISEASE . . . ; 3 So de 2, Ay uphse, RRA & oj 225:
I. CooprraTION . . 25
II. Were SHOULD THE Tvaarieannnnes OF _— Ae MIaRION Brcin? 26
III. Puan or OperaTIoN . . . vs, agile. eS) ee ay ae BE
IV. How Swati We Recorp Our Oadanaaamona? ‘: «= 27
V. How Can an Insect se INvoLvED 1n Disease Tpiuaumcian? Q7
1. What Kind of Organisms Can Insects Carry? . . s « 87
2. In What Manner May Insect Toxins Bring About Disease? . . 27
3. Can Insects Themselves Cause Disease? . 28
4. Where May Insects Obtain the Organisms Which Cause Disease? 28
5. How Can the Insect Transmit the Organism? . . . - 28
6. What is the Course of the Organism in the Insect? . . 29
7. What is the Course of the Organism on Leaving the Insect? . 29
VI. Waat 1s Known Asout THE Disease To BE INVESTIGATED? . . 30
VII. Wuat Insects SHovutp BE INVESTIGATED? . . . _ 30
VIII. Waat 1s NeEcEsSsARY IN THE TRANSMISSION Riccuienwe? wa Sl
IX. How SHoutp Exprerimentau Insects BE HANDLEDP ..... 82
Ill. A Gewnerat Survey or tHe Neeps or Entomo.ocicaL SANITATION IN
AMERICA. . Fi Be any See. es eh fiat den es aoweodh, Bh ap, onl: OR
THE Taonwenei Beau a & zi i a Os os Ses . 85
How to Improve Farm Saniwariont {6 2 4 w 24 gon ee we a we SE
Tue Insanirary TowN ...... . ee ee ew ee ee ee 8B
How to Improve SANITATION . . . . . ee ee ee ee ee BB
Sanitary PRoBLEMS OF CITIES. i dn em Be ob 39
ENTOMOLOGICAL REQUIREMENTS OF ees Si migkiian ees atte 40
INDUSTRIAL SANITATION . 1. 7 ee eee ee ee ee ee A
IV. A GeneRat SuRVEY of THE SERIOUSNESS OF INSEcT Borne DisEasEs TO
ARMIBS: ek Gla) a ea ee AP eo eG es ee) Geet ay ee AB
Y. Rewation or Insects To THE Parasitic WorMS OF VERTEBRATES . . . 50
Mops or Inrection or Insect Hosts. ............ ~ «51
Mope or InrecTION oF VERTEBRATE Hosts. ....... =. . 52
Species or Worms Founp in INSEcTS. . . . . . 2. 1 wee
be & ae 228
Horse Flies . . . . 2... a. Geos ; Rrias ea eeS
Famity Muscip2 . . As by en ty Goi Me eO
Bloodsucking Fly Larve |. . : en te 228
Biting Species of Musca . be oe Bee Roe or Boe ee Bw oe 289
True Biting Flies . . . 5 teak Re cM ee age ee 229
Stable Flies . . iS tek > be in ae ryan es 230
CONTENTS
CHAPTER
Horn Flies . . . .
Tsetse Flies . ‘
PurIpaRA ..
REFERENCES .....
XVI. Brotocy anp Hasits or Horse Futes
Eees anp Eco Layine
Larvaé
Purz.
Lire CrciEe 7
Hasits or ADULTS . :
CONCERNING CONTROL Miaaoans
BIBLIOGRAPHY
XVII. Diseases TRANSMITTED BY Mosquitos
Diseases oF UNCERTAIN OrIGIN TRANSMITTED BY hosaurress
Piant Orcanisms TRANSMITTED BY MosquiToEs
Thallophyta: Fungi... .......
Thallophyta: Fungi: Schizomycetes: Bacteriacee.
ANIMAL OrcaNIsMS TRANSMITTED BY ai
Protozoa bee th. oct
Mastigophora: Binucleata: Hemoproteide - é
Mastigophora: Binucleata: Leucocytozoids
Mastigophora: ‘Binucleata: Trypanosomidee
Mastigophora: Binucleata: Leptomonid
Mastigophora: Binucleata: Plasmodide . .
Mastigophora: Spine aee Spirochetidee
Metazoa . . ee 2
Platyhelmia: " Fasciolidze ee
Nemathelminthes: Nematoda: Filariide .
Nemathelminthes: Nematoda: Mermithide
REFERENCES
XVIII. Wasat We SHovutp Know Asovur Moseuiro BioLocy
OviposiTION AND THE Eco Stace
Tae Larva anp THEIR Hasits
Toe Pure. ..
Aputt MosquITors
Table of American Disease-Carrying Mosquitoes
REFERENCES
XIX. Moseurro ControL
PREVENTION OF Mesauns Banmine
Scouting .
Determination of Source of Mosquitoes
Leveling and Filling Water Holes
Ditching and Clearing Streams and Swamps
Clearing of Weed E Filled ie and Lakes .
Drainage . 5
Larvicides
Oiling . :
Artifeial Containers of Mosquito ‘Larve
Fish as Mosquito Control ;
Destruction of Adult Mosquitoes,
Protection From Mosqu!TorEs ; F
Protection of Dwellings from Mosquitoes :
Protection of the Individual ee
BIBLIOGRAPHY
xili
PAGE
232
234
235
235
236
237
240
243
243
244
245
246
Q47
248
249
249
249
249
249
249
250
250
251
252
259
260
260
261
262
263
266
267
268
272
272
273
274
275
275
275
276
276
276
Q77
277
279
280
282
282
283
283
283
283
285
xiv CONTENTS
CHAPTER
XX. Louse Borne Diskases . . . Bo ssersnay Ge arate SE
I. Dimect Errect or Louse Ruwaer ,
1. Types of Pediculosis Corporis
2. Types of Pediculosis Capitis
3. Types of Phthiriasis
4. Effects of Attack of Other Lice
II. Transmission or Diseases BY Lice
1. Diseases of Plant Origin . . . . .......,
Thallophyta: Fungi: Ascomycetes: Gymnoascee .
Thallophyta: Fungi: Hyphomycetes ok
Thallophyta: Fungi: Schizomycetes: Coccacee .
Thallophyta: Fungi: Schizomycetes: Bacteriacez
Summary of Plant-Caused Diseases A We id
2. Diseases of Unknown or Uncertain Origin .
3. Diseases of Animal Origin ree
Protozoa ‘
Mastigophora: “Binucleata: Trypanosomide
Mastigophora: Binucleata: Leptomonide . .
Mastigophora: Spirochztacea: Spirochetide .
Telosporidia: Heemogregarinida: Hzeemogregarinide
DM ebazog es. oN Sel Sh ge ik BN oe ss wos Hee es
Platyhelmia: Cestoda: Cyclophyllidea: Teeniidse
BIBLIOGRAPHY ae Ee SR a a
XXI. Tue Lire History or Human Lice
REFERENCES
XXII. Tue Conrrot or Human Lice
Tue Ravaces or Lice E
Reservorrs or Louse BREEDING .
Controt MEasuREs F
Controu or Lick on THE Bopy
Control of Crab Louse
Control of Head Louse .
Control of Body Louse
Controu or Lick 1n CLoTHING
1. Laundry. .
. Dry Cleaning
. Steam Sterilization
. Hot Air Delousing
. Fumigation .
. Storage ‘4
. Impromptu Delousing Arrangements
Controu or Lick in Livinc QUARTERS
Controu or Lice 1n Hospitats
Control of Lice in Hospitals.
Louse-Proof Garments for Medical Attendants, ete.
EOD St Be 09 2
BisuiockaPHY . . . 2...
XXIII. Lice Wuicn Arrect Domestic ANIMAIS. .......
Part 1. Carrie Lick anp THerr ContRoL. ......
Sucking Licés. Gin he 4 Re eS ee we we mS
Biting Lice . . a 2 RS ORR ee OS
Methods of Study of Life History a BR ORS Baul ase, Mad oie 2s
Control Measures . . . Bey a Lae case thy tay ake 1G Seat etter
Oils. ec ae ae os be Ges, ah Ser, gatucthe ~9n be Wa bt-roe eh tees
Sprays . Ss tee) are ein xe Gace ee ea
Miscellaneous Remedies oo a he Se
Time for the eyoueaim of Control Measures | ae ae ae
Skin Injuries .. ae wae. abe eg eee Gee ee ec ae 1
PAGE
286
286
286
287
287
288
289
289
289
289
289
290
290
291
294
294
294
294
295
296
297
297
297
301
311
312
312
313
314
316
316
316
317
319
319
320
321
324
324
326
326
327
328
328
328
328
330
330
331
332
333
334
334
335
337
338
338
CONTENTS
CHAPTER
Part 2. Lick Arrectinc Cuicxens, Hoes, Goats, SHEEP, HorsEs, AND
Orner ANIMALS
Lice Infesting Domestic Fowls . . .
Lice Infesting Rabbits, Cats and ions
The Hog Louse. . . . :
Lice Attacking Sheep. . .
Biting and Sucking Lice of Goats.
Lice of the Horse :
Important Bibliographical References
XXIV. Diseases CarrRiep BY FLEAS
Puant OrcanismMs TRANSMITTED BY Peas doe
Thallophyta: Fungi: Schizomycetes: Bacteriacexr .
ANIMAL ORGANISMS Eeéneuiraen By Firas .
Protozoa :
Mastigophora: Binucleata: " ‘Trypanosomidee 3
Mastigophora: Binucleata: Leptomonide ‘
Mastigophora: Spirochetacea: Spirochetide .
Telosporidia: Gregarinida: Agrippinide . ‘
.Telosporidia: Heemogregarinida: Hemogregarinide
Metaz0ag = 6s. ee
Platyhelmia: Cestoidea: Cyclophillidea: “Teniidee
Platyhelmia: Cestoidea: Cyclophillidea: Hymenolepidide
Nemathelminthes: Nematoda: Spiruride
Nemathelminthes: Nematoda: Filariide
SumMMARY
REFERENCES
XXV. Tue Lire History anp Controu or FiEas
Factors Inrtuencine ABUNDANCE OF FLEaAs
Controu oF Fieas. . . . .
List or REFERENCES é ‘
Notes oN THE CHIGOE, Dumecwennge Pinsiaens 5
KXVI. CockroacHEs
BroLocy ‘
Key To THE Four PRinctPaL Plousinoun CocKROACHES
Blatta orientalis (Linnzus) ,
Blattella germanica (Linneus), Caudell _
Periplaneta americana (Linnzus) ;
Periplaneta australasie (Fabricius) Burmeister
REMEDIES z
Fumigation . .
Hydrocyanic Acid Gas
Carbon Bisulphide .
Pyrethrum Powder .
Sulphur .
Poisons ‘
Sodium Fluoride.
Borax . .
Pyrethrum Powder .
Phosphorus bit dew BS raow &
Sulphur... 20s gg we ky aoe 8,
Castor Oil . ‘ Al 32 g Pphe. e. aah
Traps...
ENEMIES
XXVII. Diseases TRANSMITTED BY THE COCKROACH ......
Puant ORGANISMS . . «ee ee ee ee te et
Thallophyta: Fungi: Coccacee .
Thallophyta: Fungi: Bacteriacee .
Thallophyta: Fungi: Spirallacese .
xv
PAGE
339
339
343
344
345
346
347
348
350
350
350
352
352
352
354
355
355
355
355
355
356
357
357
357
358
360
366
367
371
373
374
375
376
376
377
378
380
380
380
380
380
381
381
381
381
381
382
382
382
382
382
382
383
383
383
384
387
XVI CONTENTS
CHAPTER PAGE
AnmmMaL ORGANISMS... ww ee eee ee ee 888
Protozoa . . Sue Thy op ie oe Gat ayy et GE Oa aps Ca 7988,
Sarcodina: Ameebina: Ameebidee dinid iy bs abe ; . . 3888
Mastigophora: Polymastigina: Tetramitide a) & Ge & Bole ~ 388
Mastigophora: Binucleata: Leptomonide . . ‘4 . . 388
Telosporidia: Gregarinida: Gregarinide . . . . . a3 . 388
Telosporidia: Coccidiidea: Eimeriide. ....... =... +. 388
Neosporidia: Myxosporidia: Thelohaniide . bes ee . 388
Ciliata: Heterotricha: Bursarinide . . . .... 2... . 3888
Metazoa . . aes ee 8 . 389
Platyhelmia: " Cestoidea: " Hymenolepididee be er : 389
Nemathelminthes: Acanthocephala: Gigantorhynchide 5 389
Nemathelminthes: Nematoda: Spiruride . . Se eae ad . 389
Nemathelminthes: Nematoda: Oxyuride . . ; ‘ 389
REFERENCES . . . 1. ee ee te abate ee oe Bn ae BODE
XXVIII. Tot Bepsue anp OruEeR Buioopsuckine Bucs: Disrases TRANSMITTED,
Biotocy anp ConTRoL . . . So @ ao & BOT
DIsEASES OF THE PLANT Rerason oP easneanernarnts BY — ; . . 892
Thallophyta: Fungi: Bacteriacee. . . . i A . 392
Diseases OF UNKNOWN ORIGIN . . oo ye 898
DIseases OF THE ANIMAL KINGDOM We anapiiaatiy + BY Beas iw 393
Protozoa . . ‘ : . 3893
Mastigophora: Binucleata: " ‘Trypanosomidz . ayo tn ae 2898
Mastigophora: Binucleata: Leptomonide . . ; » . . 895
Mastigophora: Spirochetacea: Spirochetide ‘ . 398
lire History Notes ..... . eh wees ace . . . . 899
TREATMENT OF BriTEs digs Ce ais . 401
ControL Measures. Foe ae a 3 ; . 401
List or REFERENCES . ...... é Bao we oe C4OR
XXIX. Diseases CausepD on Carriep By Mites anp Ticks . . é . 403
Diseases Causep BY Direct ATTACK oF Ticks anp MITES . . 403
Diseases CarrieD BY Mites anp Ticks . .......... . All
Diseases Causep BY Puant OrcGanismMs . . . 411
Disrases OF UNKNOWN ORIGIN . . . aes a Mg eae Gre ee ee TD
Disnases or ANIMAL ORIGIN... ... . ‘ oe we 414
Protozoa . . F . 414
Mastigophora: Binucleata: Trypanosomide D4 . 414
Mastigophora: Binucleata: Leptomonide .. . . 414
Mastigophora: Spirochetacea: Spirochetide oe ~ « 9 « 418
Telosporidia: Hemogregarinida: Hemogregarinide ee ee ee 420
SumMary ... ne fees Ses te be dee Pa eas 424
List oF Ransannows ee ee S. & ey Se an a . 427
XXX. Tue Biotocies anp Hasits or Ticks. - eer ; . 430
BrstiocrRapHic REFERENCES ........ . 2... ee « « 488
XXXI. Conrrout or Ticks . . 2 Be) as d - 2 . 440
List or REFERENCES .... . . £o as 2 : ~ ee 449
XXXII. Furies anp Lice 1n Ecrypr a eee ee : ‘ os « w « « 450
Tue Suvran’s FUNERAL . . . .. . 1 + ee eee ee we 5%
XXXIIIJ. Insects in Revation to Packine Housps . ..... . soe a » 453
Insect-BREEDING Places AND THEIR TREATMENT. . ... . . . 455
Protection Acainst INSECTS . . . . 458
A BretiocraPrHy oF LITERATURE Dima WITH ‘Sacnaron OF ‘Maar
Packinc EstaBLISHMENTS ... . ty CB ode) Rk Se ge oe oe HOD
CONTENTS XVil
CHAPTER PAGE
XXXIV. Insect Porsoninc aND MisceLLANgous Notes ON THE TRANSMISSION OF
Diseases By INSECTS. 2 6. we ee ee ee ee 461
Scorpion PoIsonING ..... . eo Soe ee @ =e w AGE
SprperR PoIsonIng . .... . 1. ee et woe eee 463
CentIpepDE Poisoning. . 2 1 1 ee ee ee ee AB
CrentTIPEDES IN Nasa Cavities AND ALIMENTARY CANAL Lee ee 466
Lerrpoprerous Larv@ Poisoning . . . 1 ee ee ee ee 466
Ber, Wasp anp Ant STINGS. na 8 ye Se Bees. 4 UACT
Honey Poisoning . . . . . we ee Ae e 4 we & o 468
ANAPHYRAXIS. § ¢ 2 8 4 @ oe 8 8 we * Bom 6 8 we we oe e BOB
Potsoninc From Eating Insects. . . . .. .- - oe . . . 469
Kissing BUGS « + @ 2 | @ % @ @ As # © % He % e a e w SED
Dermatitis Causep BY BEETLES. . . . 1. ee ee ee . . 469
BEETLES AS CARRIERS OF DisEasE GERMS ... . «eo we ee 409
List or REFERENCES . . . ... 1... a & Coho e « 4 AMO
SUMMARY 4 «© « %© w@ # # @ @ BF @ H&B a eS Sy ue wy A
XXXV. A Tasutation or Diseases anD InsEcT TRANSMISSION . be oe a ey AS
INDEX: 45? ede wide ae aA BR Soles Bae ee ke A a SOD
CONTENTS BY AUTHORS
By W. Dwicut Pierce—Bureau of Entomology
How Insects Can Carry or Cause DISEASE LEAs od) GEL ty oti 32
Some Necessary Steps rn ANY ATTEMPT TO Prove INSECT TRANSMISSION OR CAUSATION OF
DiskasE . . ww ww
A GENERAL Survey or THE NrEps or ENTOMOLOGICAL SANITATION IN AMERICA
A GENERAL SuRVEY orf THE SERIOUSNESS OF INSECT BorNE DisEASES TO ARMIES
RELATIONS OF CLIMATE AND LIFE, AND THEIR BEARINGS ON THE Stupy or Mepicau Ento-
MOLOGY?! “Ys eee gn Be) ees Oy BSB tee EH. HO aS
Diseases Borne By Non-Bitinc Furs . . . . 1. 0.0.0. ee ew es
Important Puases in THE Lire History or THE Non-Bitinc Furs .... .
Tae Controu or tHe House Fry ann Revatep Fumes . ......~.
Diseases TRANSMITTED BY BLoopsucKING FLIEs n> oyihe “Th Ba Sis te Ge Watt ne
A TaBULATION oF Diseases AND INSECT TRANSMISSION . . . «© «©. ew
By W. Dwicut Prerce anv C. T. Greene, Bureau of Entomology
Wauat We Saovutp Know Asour Mosquito BioLocy
By W. Dwicut Pierce anp Rosert H. Hurcurison, M.A., Bureau of Entomolo;y
Tae Lire History or Human Lice oe ORES Re ay ae ae a
Tae Controyt or Human Lick . . . . . . ee et
By B. H. Ransom, Pu.D., Zoologist, Bureau of Animal Industry
RexLation or Insects To THE Parasitic WorMS OF VERTEBRATES . . .
By F. C. Bisorer, B.S., Bureau of Entomology, In Charge Animal Insect Investigations
Controu or Fires 1n Barn Yarps, Pic Pens AND CHICKEN YARDS. . .
Myzasis. Types or Injury anp Lire History anp Hasits or Species CoNcERNED
xix
PAGE
19
25
34
43
97
105
126
152
209
223
247
275
286
350
383
391
403
461
473
266
301
312
50
167
175
XX CONTENTS BY AUTHORS
Myiasis. Irs PREVENTION AND TREATMENT
Tue Lire History ann Conrrou or FiLEas
Tae Biotocres anp Hasits or Ticks
THE Controu or Ticks
By J. L. Wess, M.S., Bureau of Entomology
Brotocy anp Hasits or Horse Firs .
By G. H. Lamson, Jr., M.S., Entomologist Storrs (Conn.) Agricultural Experiment
Station
Lice Waica Arrect Domestic ANIMALS
By A. N. Caupett, B.S., Bureau of Entomology: Curator of Orthoptera, U. S. National
Museum
CocKROACHES
By H. A. Battov, Pu.D., Imperial Entomologist, Barbados
Fires anp Lice in Ecypr
By E. W. Laake, B.S., Bureau of Entomology
Insects In Revation ro Packine Houses
PAGE
200
360
430
440
236
330
374
450
453
LIST OF TEXT FIGURES
FIGURE
1.
2.
3.
4.
5.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
Cross Section or Mann’s Hiisipe Incrnerator, Usep at U. S. MakiNnE Camp,
Quantico, Va. (Mann) :
MopirFicaTion or Mann’s HIisipE IcwvERatoR, Neaeaie: os TO ae ican
(Mann)
SMALL INCINERATOR OF THE Panauauy Ta FOR Use OF se Sirib wi, 4 AND oe
PABLE OF TRANSPORTATION. (Mann) z
SrrappDLE Trencu Latrinss, 1 root WIDE, 2 FEET DEEP, 3. FEET LONG, FOR —
Operations AT TeMPoraRY Locations. (Mann) s *
Coverep Pit Latringe LEVEL with GRouND, A SEMI-PERMANENT Tne " (Man)
GarBace Can wit Top ConvertTEeD INTO PortaBLe Urinau ror Us 1n Com-
PANY Street at Nicut. (Mann) Se a
Urine SoakacE Pit, rn Cross Section. (Mann’s Mopirication rrom LELEAN)
Cuart SHowING THE Zones oF Lire Reaction TO TEMPERATURE AND RELATIVE
Houmipiry. (Prerce) ae Sab F "i
Suecrestep Curves OF THE RESPONSES OF semen Aare roieas TO aa Tre
PERATURES. (PIERCE) . ere BD wha
. Moura Parts or Fuss: u, suctorial type}. ‘ biting nk: (Gummi)
. DiacrRamMMatic SKETCH OF THE House Fiy, Musca domestica. (GREENE) .
. ABpominaL Margines or Taree Common House Fuss: a, The house fly,
Musca domestica; b, little house fly, Fannia canicularis; c, stable fly, Stomorys cal-
citrans (GREENE). In these diagrams the relative size of the abdomen is shown.
The light areas in a and b represent yellow markings and are variable in size. In
fig.c the markings of the last segment may be present or absent ok
CHaracters OF A Muscip Fry Larva. (GrREENE.) Segment 1 is the fiead
2-4 are thoracic segments; 5-11 are abdominal. Segment 11 really contains the
seventh to tenth abdominal segments, the spiracles being on the eighth, the anus
is the tenth . oe
Larva oF THE LITTLE House Fry, Fannia canicularis. Greatly enlarged. Ea waRo
AND Pierce, Drawine By BRraDFoRD) i
DorsaL View or E1cHtH ABDOMINAL SEGMENT OF THE tue OF Fina
canicularis. Very highly magnified. (Drawine BY BraprorD) . Ae 4
VENTRAL VIEW oF TERMINAL SEGMENTS oF Fannia canicularis; the ninth anid
tenth segments are comprised in the small zone around the anus. Vent highly
magnified. (DRAWING BY BRADFORD)
Larva oF Fannia scalaris, THE LaTRINE FLy. rea magnied (Howanp AND
Prrrce, Drawine BY BRADFORD) . 08 ;
DorsaL View or EicuTH ABDOMINAL SEGMENT OF Fannia seals Very highly
magnified. (DRAwING BY BRapFoRD) eta
VentraL View or TERMINAL SEGMENTS oF Fannia scalar: “the nineh antl tenth
segments are comprised in the small zone around the anus. es highly manera
(Drawinec By BRADFORD) . ‘
Larva or Musca domestica: Dorsat VIEW OF coy AND 1 Papenenies ce
Larva oF Musca domestica: LaTeraL VIEW OF ‘TERMINAL SEGMENTS. (GREENE)
The spiracles are located on the eighth abdominal segment. The ninth and tenth
segments are ventral and not very distinct, enclosing the anus
Larva or Musca domestica: Enlarged Sketch of Right eee Plate. Thee
plates are less than their breadth apart. (GREENE) .
Larva or Stomozys calcitrans: Enlarged Sketch of Thoracic Bolenees, (Geman)
xxi
PAGE
46
46
46
47
47
AT
48
98
102
138
139
140
142
143
143
143
144
144
144
145
145
145
146
XXll
LIST OF TEXT FIGURES
FIGURE
Larva or Stomorys calcitrans: Enlarged Sketch of Right Stigmal Plate.
plates are one and one-half times their breadth apart. (GREENE) bn 6 Se
Larva or Muscina stabulans: a, Side view of head and prothorax; 6, ciate dite or
24,
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
thoracic spiracles; c, side view of terminal segments of abdomen. (GREENE) :
Larva or Muscina stabulans: Enlarged Sketch of Right pay Plate.
plates are less than their breadth apart. (GREENE)
Larva or Calliphora erythrocephala:
Larva or Calliphora erythrocephala:
plates are one and one-quarter times their breadth apart.
Larva or Chrysomya macellaria: san Sketch of Side of Head and Beitr:
(GREENE) ....
Larva or Chrysomya renedlone
head and thorax; ¢, lateral view of last abdominal segments.
A Maccor Trap ror Houserty ContTRoL.
concrete basin containing water in which larve are drowned, and the wooden plat-
form on which manure is heaped.
Use or Frytrap 1n CoNnNECTION
Side View of Head aoe pitioits
.
Enlarged Sketch of Left Stigmal Plate.
(GREENE)
‘lynied Sketch of Left Stigmal Plate.
plates are less than their breadth apart. (GREENE) . . .
Larva or Lucilia sericata: a, dorsal view of head and notices b, laden) view ror
(Hutcntson) . .....
with Manure Bin: a, Block of wood set in
ground to which lever raising doorishinged. . . .....
Tor or GarBaGE Can wiTH SMALL Batioon Fiyrrap ATTACHED
ContcaL Hoop Frytrap; Sipe View:
(GREENE)
View of the maggot trap, showing the
These
These
(Gxxmna)
These
"These
u, Hoops forming frame at bottom; 8, fies
forming frame at top; c, top of trap made of barrel head; d, strips around door;
e, door frame; f, screen on door; g, buttons holding door; h, screen on outside of
trap; 7, strips on side of trap between hoops; j, tips of these strips projecting to
form legs; k, cone; /, united edges of screen forming cone; m, BPeTnre at apex of
cone. (BISHOPP) . . ... .
Puans or Open Hoc-Ferepinc Troucu. (BisHopp) .....
Fut Grown Larva or THE HuMAN Bor, Dermatobia hominis.
ForD.) Actual length 14.5 mm. .
Furu Grown Larva or tHe Tumpv-FLy, Condylbia anthropophaga.
Ventral view. x6. (From Austen) . . . i ae a
Tae Tomepv-FLy, oe sisal (Gnismene) Female.
AUSTEN)... ses
ee oe
(Drawine By Brap-
(Grinperc.)
x 6.
eo
Nose PRoTEcTION FOR ere aecainuir ane or THE NosE Fes, Gastrophilus
hemorrhoidalis. (DovE) .. .
Cuart InuustratTinec THE Lire Cycie or p Telaadlcles columbe, THE CAUSE OF
Picron Mauaria. (PIERCE)
CuHart IuLustratine THE Lire Cycie or Trypanosoma RUNS THE douse OF
GAMBIAN SLEEPING SicKNEss. (PIERCE) .... + pte
Larva or A Burrato Guat, Simulium. Eisen eouesoe)
Eees or THE Stasie Fy, Stomorys calcitrans ATTACHED TO A StRaw. Gently
enlarged. .(Arrer BisHopp)
Tue Stasie Fry: Larva or Maageor. Ghintiy enlarged. Chsme on
Tue StaBLe Fry: Aputt Fremae, Sipe View, Encorcep witH Buoop. Greatly
enlarged. (Arter BisHopp)
Lire CycLe or Piasmopium, Cavs
Eces or Mararia Mosquitoes:
c, A. crucians. (ArTER Howarp,
ee
£ OF Pernicious Maaria. —
Eces anp Larv# or Cutex. Enlarged. (Howarp) .
a, Anopheles punctipennis; b, A. es en ee
Dyar anp Knap) ....
Larva or THE YELLOW-FEeveR Mosquito. Much enlarged. (Howanp)
Larva or tHE Mazarta Mosquito, aueplslse punctipennis.
Dyar, AND KnaB) . ....
Pura or Cutex. Greatly enlarged.
Pura or Anopheles quadrimaculatus.
fb a a a a a on?
(Hows) . Se Gh Te ae). tate
Greatly enlarged. (Howanrp)
.
.
.
(Arter Howarp,
PAGE
146
147
147
148
148
149
149
149
“155
157
160
163
171
187
189
189
205
213
215
225
230
230
230
252
268
268
269
271
272
272
LIST OF TEXT FIGURES XXxiii
FIGURE PAGH
54. Pupa or Aedes argenteus, THE YELLOW Frver Mosquiro. salve sees
(Arter Howarp, Dyar, anp Knas). ........ Lacan ta nak 272
55. Types or Mosquiro Moura Parts: a, Short palpus aay b, Tong pelpy form
(GREENE) ........ A ‘ ‘ . 278
56. Aputt Culex sollicitans. Much witinvedl: (Homann) aye SE 273
57. Tue Yettow Fever Mosquito Aedes argenteus: Aputt Femare. Much enlarged.
(Howarp) ....... B tag, Lipa tel pale te Vad de a x we 278)
58. A Matarrat Mosauito, Avonhae sented eteailcbu Mate at Lint AND FEMALE
at Ricut. Greatly enlarged. (Howarp) ..... ae j Q7A
59. SUBMERSIBLE AvuTomaTic BussLerR For DistTRiBuTING On. ‘tos ai pacce OF
Water. (Epert) . . . . far eer ‘ oe ey > BBE
60. Meruop or PEtTRo.izaTiIon WITH Gu Soicen Since. (Hem) . Bry 28 281
61. Wristtet Merxop Usep ror Breepine Lick. (Hutcuison, Puoro sy Daven) 303
62. Cuart InLusrratTine Tae Lire Crcix or Trypanosoma lewisi. (Prercr). . . . 353
63. Cuart ILLustraTING THE Lire Cycie or THE Doc Tarr Worm, Bi aaoall cani-
num. (PIERCE) . ... 2. 1 ee eee 356
64, Larva or THE Evropran. Rat Frixa, Ceratophyllus ‘faschatis. ‘Grewiy enlarged.
(BISHOPB)) gcse gp ko a Re ww, RO we 361
65. Tus Doc Fiea, Ctenocephalus canis: a, Egg; 6, larva in cocoon; c, pupa; d, ‘adults
e, mouth parts of same from side; f, antenna; g, labium from below. b,c, d, much
enlarged; a, e, f, g, more enlarged. (From Howazp) Ry ge Ges ak, 4B eh aoe RR gs Ta MOOS
66. Tae Human Fina, Pulexirritans: Aputt Femate. Greatly enlarged. (Bisnopr) 362
67. Toe Homan Fiea, Pulex irritans: Aputr Mae. Greatly enlarged. (Bisnopp) 363
68. Toe Evrorpean Rat Fiea, Corcaphaina as call Aputt Fermate. Greatly
enlarged. (BISHOPP) ..... 64 ee » . 864
69. Tue Sticktigut Fiza, Echidnophaga ene ‘ awaee FEMALE. Greatly en-
larged. (BisHopp) . . . . 1. 1 ee eed ea ae 365
70. Heap or Rooster INFESTED WITH THE Gr oniteae Fira, Hehetucphage pitniaeie.
Somewhat reduced. (BisHopp) . . ..... coe 2 ao B66
71. Tue Ortentau Roaca, Blatta orientalis: a, Female; 5, ere C cate view of female;
: d, half-grown specimen. All natural size.. (Marzarr) Bic PB We el GOT fe se OU
72. Tan German Roaca, Blattella germanica: a, First stage; b, second stage; c, third
stage; d, fourth stage; e, adult; f, adult female with egg case; g, egg case, enlarged;
h, adult with wings spread. All natural size except g. (From Ritzey). ... 378
73. Tue American Roacu, Periplaneta americana: a, View from above; 6, from ie
neath. Enlarged one-third. (Marvatt) ........ ee ee ee 879
74. Beppue: Eaa anp Newry Hartcuep Larva: a, Larva from below; b, larva
from above; c, claw; d, egg; e, hair or spine of larva. Greatly enlarged, natural size
of larva and egg indicated by hair lines. (Marnuatt) ........ . +. 396
75. Bepsue: a, Larval skin shed at first molt; 6, second larval stage immediately after
emerging from a; c, same after first meal, distended with blood. Greatly enlarged.
(CMEAREATT) +g. doeice Wap a Sn dh, ee BR es ae ah ee Pete Oe, oh a OG:
76. Bepsuc: Aputt Berore Encorcement. Much enlarged. (Maruatt) . 397
77. Bepsuc, Cimez lectularius: a, Adult female, engorged with blood; b, same from belows
c, rudimentary wing pad: d, mouth ae a, b, much hapa ce, d, highly magni-
fied. (MaRuaTT) . Bec tea al es. tee . 897
78. CHart oF Lira Creu | oF Babesia cons,’ THE CAUSE OF Conte MAtionanr Tatar
pick. (PIERCE) . . 2. 2 6 1 ee ee. ‘ 416
79. Lire Cycie or Hemogregarina canis, THE Cause OF Canine Aneta. " (Pisroe) . . 421
80. Tick Lire Cyciz, Type I. (Arren Nutraty). . ........ . 4 . 423
81. Tick Lire Cyciz, Typz II. (Arrpr Nurratt) ........ 2... . 423
82. Tick Lire Cycrz, Type JI]. (Arrer Nutrart) . . . . . . 1 1 ee ee 485
83. Tick Lire Cyciz, Type IV. (Arrer Nuttatt) ....... 1 2. . . 425
84. Tick Lire Cyciz, Type V. (Arrer NourTary) ........ 2.2. . . 426
85. Tick Lire Cyciz, Types VI. (Prerce) . . es ee oe =, 496
86. Tae Rocky Mountain Sporrep Fever Tick, Dewneunter andirront. (BisHorr) . 437
87. Mopru Curicxen Roost. (Bissoprp) . . Bladen Mee eae een, Ma age AO
88. A CrntipEepE, Scolopendra morsitans. (BRaprorp) . fe erm man aie Panda ces te ty ABS
PLATE
II.
Til.
XI.
XII.
XMI.
XIV.
LIST OF PLATES
Tue House or Typuorw Fry, Musca domestica. Greatly enlarged.
(Howarp anp Prercr, Pooto spy Dovenrr). . . . . . . . Frontispiece
I. Screw Worms anp Biow Fuss. (Howarp snp Pierce, Puotos sy Dove-
NER)! Go. eo ed Hp ge lek es ae GL, Ge cer oes ck
Fig. 1. The blue bottle fly, Calliphora vomitoria.
““ 9, The green bottle fly, Lucilia cesar.
“* 3. The American screw worm, Chrysomya macellaria.
“4. The black blow fly, Phormia regina.
Eces or THE American Screw Worm, Chrysomya macellaria, ON Murat.
(BisHopp) Riley eh sh .
Fires with Dancerous Hasits. (Howarp anp Pierce, Protos sy Dove-
NER) a0 si gs a oe ew Oe ee fables
Fig. 1. A flesh fly, Sarcophaga sarracenie.
“ 2. The non-biting stable fly, Muscina stabulans.
“3. The lesser house fly, Fannia canicularis.
4. The brilliant green fly, Pseudopyrellia cornicina.
““
. Screw Worm Insury To a YEARLING CaLr. (BisHoPP)
. Manure Box wits Frytrap Artacwep. (BisHopPp) .
Manure SprEapDER. (BIsHOPP) . .
. Roap Drag In Us ScraPiInc MANURE IN a Cow Lot on A TENNESSEE Farm.
(BISHOPP) 3-2 5 See He Ew ee RS He Se
. UnpssIRABLE Conpitions Wuicn ARE OvEercoME BY UsE or THE Maccort
Trap. A manure pile covering a large area and having little depth. Tllus-
trating the conditions which favor the greatest loss of nitrogen, and at the
same time offer the best breeding ground for flies. (HurcHIson) . . .
. Carcass Partty Destroyep By Larv# or THE AMERICAN ScREW WorM
Fry, Chrysomya macellaria. (BisHoprP)
Horse Bot Furs. (Dove) ........
Fig. 1. Gastrophilus intestinalis, the common bot.
“ 2. Gastrophilus hemorrhoidalis, the nose fly.
Puases oF THE Lire Cycie or Bot Fuiies. (BisHopr)
Fig. 1. Empty eggs of the cattle bot, Hypoderma lineata.
“© 9. Eggs of the common horse bot, Gastrophilus intestinalis.
“ 3. Full grown larva of Hypoderma lineata.
“ 4, Empty puparium of Hypoderma lineata.
“ 5, Empty puparium of Gastrophilus intestinalis.
Mernop or Arrack BY THE Common Horse Bot, Gastrophilus intestinalis.
(BisHopP) ig, =e. cans sme, Seat =O) eh ay a
Fig. 1. Eggs on horse’s legs.
“ 9. Larve attached to walls of stomach, showing lesions caused by
removed bots in center. :
Meruop or Arrack sy THE CaTTLteE Bot, or Heewt Fiy, Hypoderma
lineata. (BISHOPP) «© © 6 ee eet ee et ee es
Fig. 1. Fly ovipositing on cow’s leg.
“9° Portion of cow’s back showing larvee, empty holes, and pus exudate.
“ 3. Heavily infested cow.
Trenco PREPARED ror Burnine Carcass. (BISHOPP) .- .
XXV
PAGE
133
134
136
150
155
157
159
159
177
183
184
185
186
201
XXV1
PLATE
XV.
XVII.
XVIII.
XTX.
XX.
XXI.
XXII.
XXIII.
XXIV.
XXV.
XXVI.
XXVII.
XXVIII.
LIST OF PLATES
Pups or Simulium. (ArreR Jopprns-PoMERoy)
Fig. 1. Respiratory filaments of pupa of Simulium sittatum.
“ec
“cc
“ec
“
Fig. 1. Eggs in straw.
2. Pupz in straw.
«“e
8. Adults on leg of cow.
3. Pupa of Simulium bracteatum:
4, Pupa of Simuliwm jenningsi.
5. Pupa of Simulium pictipes, in pupal case.
. Tue Srasie Fy, Stomozys calcitrans.
2. Pupa of Simulium venustum, in BuER case.
A, Side view of filaments.
(BisHopp)
All greatly enlarged.
Straw Stack SHowinc Proper Meraop or BuriLorne Srraw Srack. (Bis-
HOPP) . .
Tue Horn Fy, Lyperosia irritans.
Fig. 1. Flies on cow,
Tapantp# ArrackInGc CatTTLe:
punctifer on top of shoulder.
(BIsHOPP)
2. Cow pasture showing droppings improperly left to breed flies.
Tabanus ia on cow’s jaw, and 7.
(BisHopr) . od ee
Tabanus punctifer. (WEBB, PHotos By DoveneEr)
Fig. 1. Egg masses on grass.
2. Larva, dorsal view.
3. Larva, lateral view.
4, Pupa, lateral view.
5. Pupa, ventral view.
“ce
““
“
Tue Cxotrainc Lovuss, Pediculus corporis.
Pxotos By DovENER)
Fig. 1. Female, ventral view.
2. Male, dorsal view.
“
Eecs or THE Cioraine Louse, Pediculus corporis . .
Fig. 1. Mass of eggs, slightly reduced, between seams oo trousers (PHoto
BY DoveENER.)
“
“cc
(PHoTo By Patne.)
Steam STERILIZER IN
leading into the other room where another carriage is seen.
Scaty Lec Mite on CBICKENS.
“6
(Pierce anpd Forcatson,
2, Great enlargement showing eggs hatching. (PHoto By PaIne.)
3. Very great enlargement showing structure of eggs with exuvie within.
Nn Detovusine Station or U. S. Army Mepican
Corps. The carriage is transferred along the rails in the foreground to rails
(Hutcuison)
(BrisHopr)
Fig. 1. Scaly feet of chickens, caused by mite attack.
2. Scaly leg mites, greatly enlarged.
Drierine Scary Lecs or CHicKEN IN CrupDE Ot.
Tue Fowu Tics, Argas persicus.
Fig. 1. Larvee under feathers of chicken.
2. Unengorged male, ventral view; much enlarged.
3. Female with eggs, dorsal view; greater enlargement.
4. Unengorged female, ventral view; same enlargement as fig. 2.
“e
“6
“cc
(BisHorp) .
Tae Cattie Tick, Boophilus annulatus.
Fig. 1. Fully engorged female.
“6
Sprayinc CuickeN Hovse witH O11 py Means or Knapsack Spray Pomp.
(BisHopp)
.
(BIsHoPP)
2. Engorged female depositing eggs.
(BisHopp)
PAGE
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232
233
236
238
302
305
323
406
407
433
435
447
SANITARY ENTOMOLOGY
CHAPTER I
How Insects Can Carry or Cause Disease !
W. Dwight Pierce
Our nation, as well as all our world civilization, is facing the greatest
crisis in its existence in these days of reconstruction. We must con-
serve human energy and keep it at its greatest possible point of effi-
ciency. This means above all that questions of health are foremost
today.
Entomology bears a twofold relationship to health. Adequate food
supply upon which human and animal health are contingent is dependent
to a greater or less degree upon insect depredations. This is the side of |
entomology which has in the past received most of the recognition, that
is, agricultural entomology. It has been generally recognized that insects
also bear a direct relationship to health, but the public has more or less
discounted the relationship, with the result that our public appropria-
tions for the study of insects affecting crops are approximately thirty
times as great as the appropriations for the study of insects affecting
the health of man and animals. The present course of lectures aims to
give the latest views in this almost unworked field of medical entomology,
with a view toward demonstrating the necessity of obtaining a better
balance in the two great phases of economic entomology.
The scope of the course embraces studies of the relationship of
insects to disease, the life history of the insects which cause disease,
and the best methods of prevention of disease causation by insects. It
is intended to be placed in the hands of the men who will conduct work
along these lines, to show them why insects are dangerous, how they are
dangerous, what their habits disclose as weak points subject to attack,
and finally, how to go about controlling them.
In my opinion the near future will see a group of professional sanitary
entomologists whose services will be available to solve the insect prob-
1This lecture was given on May 20, 1918, and mimeographed copies were dis-
tributed May 22. It has been considerably revised for the present course.
19
20 SANITARY ENTOMOLOGY
lems of municipalities, communities, and armies, as well as household and
‘commercial problems. Municipal entomology has already been recognized
in a small way by certain cities. It will become better known only by
the work of entomologists themselves who are men of vision. The prob-
lems involved in entomology sanitation demand an intensive and spe-
cialized training which few of us received in school. If we would fit
ourselves for such work it will demand great effort on our part.
CLASSIFICATION OF METHODS BY WHICH INSECTS CAN CARRY OR
CAUSE DISEASE
Long before any one knew of causative organisms in medicine it was
recognized that insects might be productive of disease. We may there-
fore assume as our first category the diseases actually caused by the
insects themselves.
(1.) Diseases caused directly by insects ——We must recognize, for
the sake of arrangement, all pathological conditions brought about by
insects whether of a serious nature or not.
1. Entomophobia.—The fear of insects, both harmless and harmful,
is a common ailment, amounting in many people to an obsession. I know
of a young lady who became so frantic over the presence of a huge dragon
fly in the automobile that the attempt to catch it led to a serious
accident. Recently a serious automobile accident was caused by a bee
sting. Many women become frantic at sight of large insects, and I
have even seen men lose all sense of courage in the presence of an
unknown species of insect. Obviously only patient and tactful educa-
tion can ever cure such an obsession.
2. Annoyance and worry.—We have all probably experienced a
sense of annoyance, amounting sometimes to worry, from insects. It
frequently happens that the annoyance increases to the point of causing
acute nervous troubles which, it is quite conceivable, might lead to
insanity. with certain people. Animals are frequently driven frantic by
insects such as buffalo gnats, mosquitoes, and horse flies, and lose all
control of themselves. We may classify these different cases of insect
annoyance in accordance with the sense which perceives it and commu-
nicates its sensations to the brain. In this manner we have annoyance
originating through sight, memory and imagination, sound, smell, taste,
and feeling.
Sight worry is initiated by the occurrence of unwanted insects in
home or garden, or on one’s person, or by their constant swarming
about until patience is exhausted and one loses control of the nerves.
A recently recorded case tells of a lady whose house was badly infested
with book lice and who was fast becoming a nervous wreck when
HOW INSECTS CAN CARRY OR CAUSE DISEASE 21
entomological service was sought and the house freed of its pests. The
constant moving of streams of ants across a floor, the sight of bedbugs
or fleas, and many other common insect occurrences may cause a nervous
person great perturbation. Recently a young entomologist was nau-
seated and made very sick for hours by the sight of a louse infested
man.
Memory and imagination worry may be exemplified by the person
impressed by anti-house fly propaganda, whose imagination sees on every
fly multitudes of fatal disease germs. A person once injured by an
insect will often experience acute revulsions of feeling on sight of another
similar insect.
Sound worry such as that induced by the singing of mosquitoes or
the buzzing of horse flies will often lead to insomnia and in the cases of
animals will cause great uneasiness.
Smell worry or annoyance from insects often takes the form of great
embarrassment. A few years ago in Dallas, Texas, Calosoma beetles were
so numerous that people walking on the streets frequently would have
one alight on them, and, in brushing the beetle off, would cause it to
expel a sufficient quantity of liquid to make the person’s presence
undesirable in polite society. Many people are so sensitive to bedbug ~
odors that when they sleep in infested rooms they are constantly aware
of the odor and are possessed of a fear that they will be attacked by
the bugs.
Taste annoyance is often caused by eating berries containing bugs,
or which bugs or cockroaches have contaminated. This may often cause
nausea.
Finally, there is the worry aroused by contact of insects, the tingling
sensation from insects crawling on the body, the peppery sting of gnats
and mosquitoes, the itching sensations from vermin. Insomnia is a
frequent result of such attacks.
Thus as results of insect annoyance, we may have worry, nervous
exhaustion, excitability, hallucinations, frenzy, insanity, nausea, insomnia
and nervous chills.
3. Accidental injury to sense organs.—There are numerous cases on
record of insects accidentally obtaining access to the ear or nose and
causing a stoppage of these organs, or of insects flying into the eyes
causing severe irritation or even blindness. Certain “species of gnats
are especially annoying when there is any kind of catarrhal affection
of these organs. Myriapods have frequently been recorded as entering
the nose of a sleeping person.
4. Poisoning.—Insects and the related arthropods may poison in a
variety of ways. The bite of a tick, flea, spider, mosquito, horse fly,
etc., may cause a severe local irritation and poisoning. The poisonous
22 SANITARY ENTOMOLOGY
centipedes have a poison sac opening on the front pair of legs. The
scorpion stings with the tip of its tail. The bee, wasp, and ant sting
with the ovipositor. Many of these injuries are very painful. Certain
lepidopterous larve are provided with barbed hairs which contain
poisonous secretions, as the brown tail moth larva, and the larve of
Lagoa, Hyperchiria io, etc. Some insects emit poisonous secretions
which blister (Meloid beetles). Some of the South American honey bees
(Trigona) store poisonous honey.
5. Paralysis—The bite of several species of ticks (Dermacentor
andersoni (venustus), for example, may cause paralysis with sometimes
fatal results. Some spiders, ants, bees, wasps, and caterpillars inflict
such a poisonous wound that temporary paralysis of the limb follows.
6. Dermatosis.—Direct attack upon the body of men and animals,
and parasitism thereon, is not unusual. We have as striking examples
the dermatoses caused by lice (pediculosis), by the chigoe, the red
bug (chiggers), the Dermatobia hominis, creeping worms, scab and
itch mites (acariasis). Many of these attacks have serious after results,
as for instance an acute attack by the chigoe may result in ainhum, the
loss of a toe or a foot. Many secondary diseases obtain access to the
* body through the skin attack of insects.
7. Mytasis and similar internal attacks—Under this heading are to
be considered cases in which insects are present in the tissues of internal
organs of the body. The occurrence of insects has been recorded in
organs of the head, in the intestinal canal, the reproductive organs,
and the body wall. When the insect is a fly the disease is called Myiasis.
When a beetle is the cause, the disease is called Canthariasis, and if a
lepidopterous larva is responsible it is known as Scholeciasis. Many
species of flies have been recorded as occurring in the human body. These
will be studied in detail in a later lesson.
(II.) Diseases carried by insects —The ways in which insects may
carry diseases are very diverse, due to the great differences not only in
the habits of the insects, but also of the disease organisms and the
hosts.
1. Diseases carried by insects to food—When insects carry disease
germs to food or water we speak of the transmission as contaminative.
Contaminative transmission of disease organisms to food by insects is
naturally the simplest manner of transmission. This is necessarily done
by insects which frequent excretionary substances and also visit foods,
such as certain flies, ants, roaches, and beetles. It is obvious that we
must look upon all insects which breed in fecal matter, sputum, etc., as
potential disease carriers. Considerable research has already been con-
ducted to prove the actual réle of many species of coprophagous insects.
The réle of the carrier may either be mechanical or biological.
HOW INSECTS CAN CARRY OR CAUSE DISEASE 23
Many disease organisms are transmitted by insects which exercise
apparently only a mechanical réle. Principal among these are bacteria
and certain parasitic worms. Many of the bacteria may be taken up by
fly and beetle larvae, and by adult flies, beetles, roaches, and ants, and be
carried on the body or ingested and passed through the body and out
in the feces without modification or multiplication. A number of species
of parasitic worms may be taken up in the egg stage by insects and
deposited in the insect’s feces. If such infested feces happen to be
deposited on food, contamination and infection may conceivably follow.
Certain other organisms which are carried by insects to food pass
part of their life history in the insects. Such are some of the nematodes
that may be ingested by coprophagous insects, which in turn are eaten
by the animals that serve as final hosts of the parasites.
2. Diseases carried by insects to wownds.—We can make the same
division of these diseases into mechanical and biological carriage. The
transmission of anthrax, leprosy, ophthalmia, and such diseases, from
sore to sore or from excreta to sore is purely mechanical. When the
organism passes part of its life cycle in the insect we might call the
transmission biological. As examples of such types of transmission we
may cite European relapsing fever and trench fever, louse-borne diseases
which gain access to the body by the scratching in of fragments of the
lice or their excreta.
3. Diseases gaining access through direct attack of insect—Most of
the protozoal diseases and some of the parasitic worms gain access to
the body of the vertebrate host by direct inoculation, or indirectly, at
the time of feeding. When the organism is taken up by the insect
it begins its development in the insect body and finally reappears in the
salivary glands or some other position adjoiming the mouth parts, the
inoculation occurring during the blood feast. Such is the inoculation of
malaria, .yellow fever, and Rocky Mountain spotted fever. But other
disease organisms pass through the intestinal canal of the insect and out
in the feces and yet obtain access to the wound by being washed into it by
body secretions of the insect, as is the case of the organism of African
relapsing fever inoculated by the tick Ornithodoros moubata.
WHY IT IS NECESSARY TO KNOW HOW INSECTS CARRY DISEASE
In the foregoing discussion I-have attempted to analyze the methods
by which insects can cause or carry disease. There is also a practical
side of the question. We must know the why and the wherefore and the
what to do.
Without a conception of the réle of the insect we cannot give suf-
ficient force to our arguments, or reasons for taking a particular course
24 SANITARY ENTOMOLOGY
of action. For instance, if we were merely to go before the inhabitants
of a Montana valley suffering from Rocky Mountain spotted fever and
say: “We are going to put down this epidemic, you must dip your horses
and trap all the rabbits and rodents on your plavs.” \what kind of an
answer would we get? If the Public Health Servic: had stepped into
New Orleans on the announcement of a plague case and ordered every-
body to rat-proof their cellars, without further reason, they would have
been driven away.
If a sanitary officer reports to his superior that a certain thing
must be done, requiring a considerable outlay of money and the use of
a good many men, he must be able to give him a strong, forceful argu-
ment to prove that he is right. Army officers, and in fact most executive
officers, want brief answers. The subordinate must therefore have his
information on the tip of his tongue.
We have seen by the above discussion that the bites of insects must
be avoided. Where disease-carrying insects are present, the greater
the concentration of human beings or animals, the greater the necessity of
exercising control, whether it be in a municipality, a commercial estab
lishment, an army, a stock yards, or a ranch. It is incumbent upon all
men charged with entomological sanitation to learn the bloodsucking
fauna about them. Without a knowledge of how mosquitoes, horse flies,
bedbugs, lice, stable flies, gnats, and ticks breed, one can scarcely proceed
to prevent their breeding and consequently cannot protect men and
animals from their attacks.
One must always prevent insects from coming in contact with wounds.
This is especially important in hospitals and during times of epidemics.
It is at all times imperative to keep food untouched by anything in the
form of insect life. Insects must not be tolerated in dwellings, no
matter whether there is evidence against them or not. There is evidence
against most of them.
Domestic animals must likewise be kept as free as possible from
insects. Some day we will recognize that stables should be as well
proofed against flies as dwellings are now. There are more inducements
for flies and other noxious insects around a stable than anywhere else,
and the stable is therefore the direct or indirect source of many of our
troubles. The measures necessary for holding down insect infestation
of stable and barn yards are therefore of primary importance. But to
emphasize this importance there must be back of every measure taken or
recommended an argument in the form of a proof of danger if the measure
is not carried out.
CHAPTER II
Some Nécessa steps in Any Attempt to Prove Insect Transmission or
Causation of Disease 1
W. Dwight Pierce
The study of the causation of disease is attracting far more attention
today than it ever has in the past, but it is to be regretted that there is
not a larger proportion of this effort being directed toward locating
the possible intermediate hosts and invertebrate carriers.
Many excellent investigations have been carried out with all other
phases complete, but the question of invertebrate carriers is often left
in a very indeterminate stage. The majority of the investigations which
have been seriously undertaken to determine invertebrate carriers have
been conducted on other continents than ours. There is a great field for
investigation along these lines open to the investigators in America. In
order to stimulate such research, I have attempted in this paper to set
down some of the necessary steps for successful investigation.
1
I. COOPERATION
I consider essential to a thorough, investigation of disease trans-
mission, the establishment of a perfect working agreement and hearty
cooperation between one or more physicians and diagnosticians, one or
more parasitologists, and one or more entomologists. It is not safe,
nor does the effort bring the proper amount of credence, when one man
attempts to do the whole work. Each phase of such an investigation
should be handled by an expert on that phase. The day of the solitary
investigator is past and we are now in an era of group-investigations.
which carry with them weight and conviction. Of course certain pre-
liminary steps may easily be taken by any one member of a proposed
group or it may be possible that they may arrive at an advanced stage
by independent work, but the time will come in each investigation’ when
a cooperation of investigators will attain the most satisfactory results.
1This lecture was printed in Science, n. s. vol. 50, No. 1284, pp. 125-130, August 8,
1919.
25
26 SANITARY ENTOMOLOGY
Il. WHERE SHOULD THE INVESTIGATIONS OF INSECT TRANSMISSION
BEGIN?
There are two distinct lines of approach to this problem of insect
transmission. The first is to work from the known disease and to ascer-
tain by experimentation what species of insects might be concerned in
its transmission. The other line of approach is to make a study of all
the insects which might be involved in disease transmission and to obtain,
by cultures and microscopic studies, a knowledge of the parasitic organ-
isms normally and occasionally found in these insects. Working on this
line of investigation, one might in time of an epidemic start with insects
visiting excreta and attempt to ascertain whether the organism of the
disease at that time epidemic occurs in any of these insects.
The first line of investigations would arise from public necessity and
probably be initiated by physicians and parasitologists, or by the sugges-
tion of entomologists.
The second line of investigations would probably originate as problems
assigned by a professor or head of a laboratory to students or investiga-
tors under his direction. It is highly desirable that such studies be com-
menced in as many institutions as practicable in the near future. Such
investigations will include bacteriological studies, protozoological studies,
and helminthological studies, as well as investigations of the life histories
of the insects, and the possible connection between them and disease
transmission.
Ill, PLAN OF OPERATION
Before starting out on any line of experiment in this subject, there
should be written down in concise form the facts already gleaned, on the
practical problems and the theories which have occurred to the various
members of the group. A clearly outlined course of action should be
made and be carefully discussed and then the various steps in the inves-
tigations thus outlined should be read and modified to meet the changing
views resulting from the experiments. The course of the work should
always be kept plainly in view. Each step should be rigorously and
skeptically scrutinized for defects.
Inasmuch as the investigation from this point will consist of the
answering by observation and experiment of a series of pointed ques-
tions, I shall proceed with my discussion in the form of queries. Prob-
ably many other vital queries will occur to the reader, but it is more
than possible that he may overlook some of these if not set forth here.
When each query is satisfactorily answered the problem is practically
solved.
STEPS TO PROVE INSECT CAUSATION OF DISEASE 27
Iv. HOW SHALL WE RECORD OUR OBSERVATIONS?
Undoubtedly the most satisfactory method of making a large series
of records is to use some type of loose-leaf card or sheet filing system.
By such means one can always keep in an orderly arrangement all the
facts so far obtained. In the case of investigations of the causation of
a given disease, one of the most satisfactory methods which has been
used for recording observations is to prepare a little blank booklet, which
will fit the filing system, in large quantities, each book to represent a
case. This book should contain pages for each phase of the question,
with blanks covering all kinds of minutia about this phase. The whole
series of observations can be tabulated for each point.
Vv. HOW CAN AN INSECT BE INVOLVED IN DISEASE TRANSMISSION?
Insects may be involved in disease transmission either by the trans-
mission of an organism or the inoculation of a toxin, or they may be an
intermediate host in the life cycle of an organism, but not come directly
in contact with the final host.
1. What Kind of Organisms Can Insects Carry?
It has been demonstrated that insects can carry bacteria, fungi, many
types of protozoa, and many species of parasitic worms, and also that
certain species of insects may be instrumental in carrying eggs of other
species of insects which cause disease.
2. In What Manner May Insect Toxins Bring About Disease?
Many species of insects which bite inoculate at the time of the bite a
toxin which may at times cause serious trouble.
Some invertebrates inoculate the toxin by means of the mouth, some
by means of a claw, some by means of a caudal appendage, others by
means of the ovipositor. In some cases the invertebrate penetrates the
skin with its mouth parts and as long as it is adhering, toxins are created
which may in certain cases cause severe paralysis or death. The acci-
dental eating of certain insects in food will cause poisoning because of
the toxins contained in the bodies of the insects. It is believed, but not
yet satisfactorily demonstrated, that the pollution of food by the excreta
of certain insects may cause certain nutritional diseases.
The presence of certain insects in the tissues causes severe irritations
and often the formation of toxins.
28 SANITARY ENTOMOLOGY
3. Can Insects Themselves Cause Disease?
Many species of insects are known to live parasitically upon the
bodies of man and animals and by their constant sucking of blood or
gnawing, cause skin diseases. Other species of insects habitually lay their
eggs on or in the flesh and breed commonly or exclusively in living flesh,
causing a destruction of the tissues. Many species of insects are depen-
dent upon mammalian blood for the necessary nutriment to bring about
reproduction. Some insect larvae are bloodsuckers. It is not at all
uncommon for insect larvae to be ingested in food and for them to con-
tinue their development in the intestines or other organs, often at the
expense of the tissues. In some parts of the world insects are eaten as
food by the natives, sometimes in a raw state, and it is not uncommon
in such case for the natives to be infected with parasitic worms which
pass their intermediate stages in the bodies of these insects.
4, Where May Insects Obtain the Organisms which Cause Disease?
Disease organisms may be taken up by insects directly from the blood
of an infected host, or they may be obtained by contact with infected
surfaces of the body or taken up from the feces or other excretions of
an infected host. The insect may take up the organisms from these
excretions either in its larval or its adult stage.
5. How Can the Insect Transmit the Organism?
The organism may be transmitted by the insect by direct inoculation
through the proboscis, involving the active movement of the parasite, or
the passive transmission of the parasite in the reflex action which takes
place in the sucking of blood. The organism may be externally carried
on the beak of the insect and mechanically transmitted at the time of
sucking. It may be located in the mouth parts of the insect and burrow
through at the same time the insect is feeding. It may be in a passive
state on the insect and become stimulated to attack the host when it
comes in contact with the warm body. The organism may be regurgitated -
by the insect on the body of its host and obtain entrance by its own
activity, or by being scratched in or by being licked up by the host.
On the other hand, the organism may pass through the insect, and
pass out in its feces, or in Malpighian excretions. It may be washed into
the wound made by the sucking of the insect, by fluids excreted at the
time of the feeding. It may remain in the feces on the host and ultimately
be scratched in or licked up by the host.
The organism may be taken up by the insect and never normally pass
out of the insect, but be inoculated by the crushing of its invertebrate
STEPS TO PROVE INSECT CAUSATION OF DISEASE 29
host upon the body, and the scratching of infected portions of the
insect’s body into the blood; or may be transmitted only by the ingestion
of the insect itself by its vertebrate host, or accidentally by some grazing
animal. In fact quite a series of disease organisms find their way into
their hosts because of the habit of the animals of feeding upon insects.
6. What Is the Course of the Organism in the Insect?
If the organism is taken up by the insect in its larval stage, it may
pass directly through the larva and out in its feces and may quite con-
ceivably pass in this manner through insect after insect larva before it
finally finds a vertebrate host. The organism may be taken up by the
larva and remain dormant in some portion of the larva’s anatomy, or on
the other hand, it might undergo considerable development and multipli-
cation in the larva and remain there through all the metamorphosis of
the insect until the latter arrives at maturity, at which time development
of the organism may begin or may continue.
Upon being taken up in the blood by the bite of the insect, the organ-
ism may lodge in the esophagus and carry out all its metamorphosis
there, or in some of the organs of the head and find its way into the
salivary glands and through the salivary secretions into a new host.
It may, on the other hand, pass back into the gut, or into the stomach;
from the stomach its path may lead in many directions. It may pass on
in its course of development into the rectum and out in the feces, or it
may enter the fatty bodies, or pass into the general cavity of the
insect, or it may migrate forward into the esophagus and into the labrum;
and it may pass into the Malpighian tubules, or into the ovaries.
The organism may enter the eggs and remain therein through their
development into the larvae, nymphs or adults, and be transmitted at
some stage of the development of the second generation. Some diseases
can pass on even to the third generation.
%. What Is the Course of the Organism on Leaving the Insect?
The organism may leave the insect in the saliva and immediately enter
the feeding puncture. It may bore through the labium of the insect at
the time of feeding and enter the puncture. It may leave the rectum of
the insect, or the Malpighian glands and be washed into the puncture by
means of the secretions of the coxal glands, or some other: excretions
made at the time of feeding. It may be excreted in Malpighian secre-
tions, or rectal feces, or regurgitated in vomit, and may lie dormant on
the skin of the host, or on the food of the host, until it is scratched into
the blood, or is taken into the mouth.
30 SANITARY ENTOMOLOGY
On the other hand, it may be possible that the organism requires
another host after the insect, and before it reaches its final host. There
are cases on record of the insect being the first host, and two or three
vertebrates in succession being hosts of later stages.
VI. WHAT IS KNOWN ABOUT THE DISEASE TO BE INVESTIGATED ?
It is a primary essential that all the workers be able to recognize
the disease which they are trying to study and that they be fully informed
about it, so that they may be able to grasp possible solutions of their
problem. They will, therefore, seek first to answer the following ques-
tions:
1. What is the history of the disease and how long has it been
known? How serious has it been?
2. What is its distribution?
3. Does it occur in pandemic, epidemic, endemic or sporadic form?
4. In what seasons of the year is it most prevalent?
5. Is there any apparent relationship between its distribution and
the physical, biological or climatic features of the countries where it
occurs?
6. Does it affect any particular group, occupation, sex, age, race
or nation of people, or any particular species of animal?
%. May any wild animal be considered as a reservoir?
8. Has immunity or difference of susceptibility been recognized and
under what circumstances?
9. What are the symptoms of the disease?
10. What is known regarding immuno-chemistry and bacteriology
of the disease?
11. What have autopsies shown?
12. What treatment has been designated?
13. What is known or suspected about its causation and dissemina-
tion? What organisms have been connected with it?
14, What possible theories can be advanced to account for its
causation and dissemination?
A little time spent in collecting these facts may save much effort
later.
VI. WHAT INSECTS SHOULD BE INVESTIGATED?
A thorough entomological study of this question may prove a valuable
short cut to the investigation. Many insects will be eliminated by the
entomologist before he has finished his preliminary work. He will attempt
to answer the following and many other questions and will probably
have to answer them to the satisfaction of all his fellow workers.
STEPS TO PROVE INSECT CAUSATION OF DISEASE 31
1. What insects coincide in distribution with the general distribution
of the disease?
2. What insects occur in peculiar habitats of the disease?
3. What bloodsucking insects occur in the locality under investi-
gation?
4, What is the relative abundance of these insects?
5. Is there a coincidence between the season of abundance of any
of these insects and of the disease?
6. What insects occur in the homes, nests, or haunts of infected
hosts?
4%. What insects are found on infected hosts?
8. What insects occur in the working quarters of the patients?
9. What insects would be most apt to affect the particular group
of hosts most susceptible?
10. What insects breed in or frequent the excreta of the hosts?
11. What insects are found at the food of the hosts?
12. What insects are found at the sources of the food of the hosts,
such as the milk?
VIII. WHAT IS NECESSARY IN THE TRANSMISSION EXPERIMENTS?
The investigations which have preceded will have narrowed the ques-
tion down to certain species or groups of insects which need to be
critically studied. All of those insects which come in contact with the
blood or mucous membranes of the patient, or the food of the patient,
or the feces of the patient, must be given special attention. At this
point the bacteriologist, protozoologist, or the helminthologist finds his
special work beginning. There will be many points which must be worked
out by cooperation of the parasitologist and entomologist.
Considering first the bloodsucking insects, it is necessary to deter-
mine:
1. Can the particular insect take up the organism with the blood?
2. Does the organism pass into the intestinal canal or does it stop
at some point en route?
3. To what extent is the organism digested by the insect?
4. In what organs of the insect can the parasite be demonstrated
from day to day?
5. Are any changes in the organism demonstrable?
6. What path does the organism seem to follow in the insect’s body
from day to day?
%. Does this movement of the organism suggest whether the trans-
mission is by inoculation or does it suggest that the organism will pass
out of the body in some of the excreta?
32 SANITARY ENTOMOLOGY
8. Can the organism be demonstrated in the mouth parts of the
insect at the time of feeding?
9. Can the organism be found in any of the excretions of the
insect ?
10. How long is it before the organism reaches the mouth or the
rectum?
11. What is the earliest date at which it can be found in the
feces?
12. What is the earliest date at which infectivity of the host can
be obtained by the sucking of the blood?
13. What is the earliest date at which infectivity can be obtained
by scratching in of the feces or portions of the insect?
14. Can infection be obtained by either natural or artificial inocula-
tion without demonstration of the organism?
15. Is the infective organism,, contagium or virus filterable?
16. Can the virus or organism be transmitted hereditarily by the
insect ?
17. At what stage of development in the second generation does
hereditary transmission become possible?
18. Can the organism be taken up by the immature stages, feeding
in infected excreta?
19. Can the organism be taken up by immature stages of an inverte-
brate feeding on the host?
20. How long can the immature forms of the invertebrate, infected
by whatsoever manner, retain the organism in their system?
21. Does the organism stay in the insect during metamorphosis?
22. Does the organism undergo any changes preceding or following
metamorphosis of its invertebrate host?
23. At what stage in the metamorphosis does the insect begin to be
infective after taking up such organisms?
24, How long can the insect remain infected and infective?
IX. HOw SHOULD EXPERIMENTAL INSECTS BE HANDLED?
A large proportion of the failures in studies of insect transmission in
the past have arisen from improper handling of the insects. The breeding
and handling of the insects is an art in itself, just as is the culturing of
bacteria or protozoa. In fact, there are more diverse requirements
for handling insects of different species than can be found elsewhere in the
animal kingdom.
1. What must be known about the insect before beginning trans-
mission experiments?
The normal conditions of life of the insect must be ascertained :—its
STEPS TO PROVE INSECT CAUSATION OF DISEASE 33
reactions to heat and cold, moisture and dryness, disturbances, color,
light, odor; its food, and the proper condition thereof; its methods
of reproduction, and what food is necessary for reproduction; if soil
should be provided, and what conditions it should be in; if water should
be provided, and whether this water should be alkaline or acid, clear or
containing foreign matter, and in such case what type of foreign matter;
whether the water should be still or in motion, warm, moderate or cold.
2. What type of breeding cage should be used?
A breeding cage must be used which will most nearly enable the
experimenter to keep the insects under control and yet reproduce essen-
tial conditions for maintaining normal, healthy life of the insects and
normal reproduction. Much of this information is available in entomo-
logical literature. Many insects probably involved in disease transmis-
sion have not been properly studied and breeding technique is yet to be
worked out.
3. Water is necessary in some form in practically all insect breed-
ing. °
There are more failures to properly breed insects traceable to im-
proper humidity, or to the lack of moisture in the proper form for the
insects to drink. Much detailed observation may be necessary to obtain
this important information in the case of many insects.
4. There is a combination of temperature and humidity most favor-
able for life, for each species, and differing from one species to another.
5. The food of an insect must be in a particular condition in order to
obtain normal breeding. It may require a certain degree of immaturity,
ripeness, or fermentation. It may require a certain degree of desicca-
tion.
Many other details must be attended to by each specialist involved
in the investigation, and we probably have yet to see a single disease
problem which has been completely rounded out and solved for the future
generations.
CHAPTER ITI
A General Survey of the Needs of Entomological Sanitation in
America +
W. Dwight Pierce
Notwithstanding the great amount of publicity which has been given
the Anti-fly Campaign, one will find throughout our land a rather
general disregard of the danger from flies. Certain newspapers keep
the subject annually before their readers, but on the whole, public co-
operation is slight. A few cities and communities have definitely organ-
ized mosquito control work, and the Public Health Service has done a
wonderful amount of work in organizing such efforts. From an ento-
mological standpoint our nation is not sanitary. The reason lies in the
fact that the public does not yet realize that insects can and do carry
disease. Science has apparently not put forward the idea in such a
manner that it has gripped the average person. Until we do this we
cannot expect public cooperation in the attempt to put down insect-
spread diseases,
The problems we have to meet may be divided in several different
manners. We may separate them into problems of municipalities, towns
and villages, and rural communities. We may look at them from the
standpoint of the farm, the home, the market, the factory, and the
institution. They may be sorted out as problems of drainage, waste
disposal, screening, animal control, etc.
Of course we have a greater diversity of entomological contro: prob-
lems in a municipality, but we also have more people who give attention
to matters of health in a city, and who would complain against un-
healthful conditions. On the other hand, while the problems of the rural
community and town are fewer, the insect conditions often become greatly
aggravated because of total carelessness as to sanitation. This careless-
ness in small towns and farms is usually due either to ignorance or lack
of organized effort for community betterment.
The field of the sanitary entomologist who desires to tread virgin soil
is therefore to solve the ways and means of obtaining better fly and
mosquito conditions in rural communities. Educational work must be
*This lecture was mimeographed and circulated to the class in January and ap-
peared in parts in The American City, for February and March, 1919.
34
NEEDS OF ENTOMOLOGICAL SANITATION IN AMERICA 35
carried out which will be of such nature that it will bring results. We
have the theories and the scientific facts but we must give the public
practical] demonstrations that freedom from insect pests means reduced
sickness.
Any person informed on this subject who has traveled much in rural
sections of this country and seen the unobstructed entrance of myriads
of house-flies to the dwellings, especially the kitchens and dining rooms,
and then has stepped outside and within a few feet found the open privies
breeding these flies, cannot help but feel a sickening sensation and a
revulsion toward eating anything that the flies could have polluted. It
is not at all uncommon in rural sections to see babies exposed to the unre-
stricted visits of flies, and their milk bottles covered with them. The
writer has been informed over and over by physicians in small towns
that when infantile diarrhea or any other intestinal complaint visits a
“ town it makes the rounds of every infant in the town, unless perchance,
some mother is more advanced in her knowledge of such matters and
keeps her baby constantly screened. When typhoid fever and dysentery
visit towns with open privies and unscreened houses or hotels only the
more cautious and more resistant escape. Such communities offer every
conceivable opportunity for the spread of diseases by flies.
THE INSANITARY FARM
For fifteen years the writer has traveled extensively in rural communi-
ties, principally in the Southern States, where insanitary methods, if
existent, aggravate disease conditions because of the more favorable
climate and greater number of maladies present. We may picture, there-
fore, a few of the conditions which have been repeatedly seen in these
travels, in order the better to show the problems to be met. We shall not
claim that these pictures represent the predominant, or the usual, or the
average condition. Let it suffice that they exist sufficiently often to make
them worthy of serious attention.
The farm we will describe has been seen countless times. The house
has no screens on the windows, in fact, often has no window panes, or
may have wooden windows which are open all day. The house is one~
storied with an outside chimney, and an open fireplace. The chimney and
fireplace offer excellent day hiding places for mosquitoes, which are
abundant if there is a slough or bayou nearby. The house is built on
stumps or pillars raised above the ground. The pigs and chickens, dogs
and cats, wander freely underneath. The house has a great open hall-
way through the middle, separating the bedrooms from the living rooms.
On account of the numerous flea-breeding animals which pass under the
house, fleas are not at all uncommon in the house. The well is usually
36 SANITARY ENTOMOLOGY
open and built into the back portion of the porch. Mosquitoes breed in
it. There is a poorly constructed, dilapidated privy for the women not
far from the house, but the men have none, or if they do, it is not fit to
enter. They usually defecate in the open, in the fields or draws, or in a
woodland patch. The barn is roughly constructed. The manure is piled
in a great pile beside the barn, and breeds multitudes of flies. The stable
floor is urine- and manure-soaked and affords excellent fly-breeding
quarters.
Naturally, I have described the worst common type of farm, because
on this must be built the structure for better sanitation in farm life.
In many cases a large number of such places may exist on a single
large plantation, for the use of the tenants. In such cases a single man
is responsible, who himself lives in a house with all modern sanitary
conveniences.
The problem of the sanitarian and the sanitary entomologist is to
prove to the individual farmer and to the planter landlord the financial
value of better sanitation. The planter must be shown that inasmuch
as the efficiency hours of his tenants are increased, in proportion will
their products be increased, and in like manner his rental, especially
where the rental is based on certain proportions of the crop yield. He
must see that reduction of mosquitoes means reduction of malaria inci-
dence, that reduction of flies reduces the incidence of typhoid, dysentery,
diarrhea, and other intestinal complaints, and that as the sickness rate on
the plantation is decreased the labor output is increased.
It will do us no good to theorize if we do not set down clearly the
ways and means of accomplishing this greater farm output by reducing
fly and mosquito breeding. In the present course of lectures will be
found the proofs which have accumulated against these various insects,
brief statements of how these insects live, and detailed plans of the
approved methods of control. Fortified with this ammunition and more
which he will personally gain, the sanitary entomologist must fight for
better sanitation.
HOW TO IMPROVE FARM SANITATION
At this time, however, we may in brief state a few measures which
should be taken on every farm in order to accomplish greater farm labor
efficiency and improve the health of the household and of the animals.
1. The windows and doors should be screened against flies and
mosquitoes. During the months that fires are not used the chimneys
should have a screen over the top and the fireplace screened. If wire
screening cannot be afforded, mosquito bars can be used. In the majority
of cases the expenditure of the necessary amount of money to properly
NEEDS OF ENTOMOLOGICAL SANITATION IN AMERICA 37
screen the place will be offset by a greater reduction in doctor’s bills for
the women and children at least.
2. Where there are many children passing in and out flies will get
in. The children should be taught to use fly swatters. No flies should
ever be allowed to remain in the kitchen and dining rooms. Flies which
visit food will deposit on it any disease organisms they have picked up.
If the water is pure, the fly is about the only common means of conveying
intestinal diseases to the family.
3. Unless the babies and small children are kept indoors in screened
rooms, the helpless children should have a mosquito bar over the carriage
or basket so as to protect them from flies. This is absolutely essential
if there is any sickness in the neighborhood.
4. There should be installed sanitary pit or bucket privies such as
are recommended by the Public Health Service. Both men and women
should be provided with such, and it should be aerule of every farm that
indiscriminate defecation is absolutely forbidden. As many farms are
quite large the most feasible plan would be to place at various places
over the farm where they would be most convenient and best protected,
some type of latrine, such as is used by armies, or better still a perma-
nent privy.
5. The well should be kept covered to prevent as far as possible
mosquito breeding and contamination.
6. The foundations of the house should be boarded up to prevent
the access of animals and to eliminate a favorite mosquito hiding place.
The ground around the house should be so drained that water will not
flow under the house except in case of*heavy rains, and in such cases will
quickly drain off from under the house.
4%. All ditches, ponds, streams, and bayous on the farm should have
the banks kept clear of obstructions to the free flow of the water. There
should not be any tree stumps, trees, roots, weeds, or logs in the stream.
The banks should not have overhanging ledges, or puddle pits. Per-
manent ponds and lakes might be stocked with mosquito-eating fish.
Places which habitually form puddles after rains should be filled and
drained.
8. The barns should have hard packed dirt floors or cement floors.
All manure should be removed daily from the barn. If possible the
manure.should be spread while fresh on fields lying fallow. Otherwise the
manure should be piled in tightly packed stacks or on platforms over a
cement basin containing water, in order to drown the fly larvae migrating
for pupation.
9. The garbage should be fed to pigs, preferably in sanitary feeding
stalls as described by Bishopp in the lecture on the control of flies in
barn yards, pig pens and chicken yards (Chapter XI).
38 SANITARY ENTOMOLOGY
10. State Boards of Health should follow the California plan and
forbid the marketing of fruit dried on farms with open sewage, or where
exposed to visits of flies,
THE INSANITARY TOWN
In these same travels in which so many insanitary farms were seen,
the writer has sojourned in or passed through many towns which might
be described as follows: The streets are unpaved and are littered from
one end to the other with papers, cans, and the accumulation of months of
manure droppings, and are altogether filthy and unattractive. The
removal of trash is nobody’s business. The grocery stores and meat
markets are unscreened and have open doors. The food is covered with
flies. Farmers drive up and buy a side of salt pork or other meat,
throw it into the pit of their wagon, uncovered, and drive down the
dusty road, with a swarm of flies hovering over the meat. The small
lunch rooms where the visiting farmer eats his noon or evening repast
are dirty and full of flies. The stores have privies in the rear which
are filthy and an offense to any decent person. Flies abound. Chickens
and pigs wander unrestricted through the streets and are often found
feeding under the privies. The hotel dining rooms and kitchens are
always full of flies and are usually but a short distance from filthy
privies, and flies are constantly passing back and forth. Cockroaches are
served in the food and wander unrestricted everywhere. The bedding is
often unclean and has been slept in by some one else. Bedbugs are not
uncommon. The water pitchers contain mosquito wrigglers. The cis-
terns behind each house are unscreened, and contain rain water, full of
mosquitoes. The livery stable has great piles of manure in the stable
yards and sometimes right out on the sidewalk.
Sometimes the town is a little bigger and the people have become more
civilized and installed interior plumbing, which empties the sewage into
a ditch which runs down to a stream from which cattle drink, or quite
‘ often this sewage empties into the gutter on the street and fills the air
with filthy odors. Such is not an uncommon thing in America. Only
a few years ago we could have pointed out quite a number of cities in the
100,000 class with open sewage.
These small towns are often rat infested, and one can easily see
the danger should an outbreak of plague, which is transmitted by the
rat flea, get a start in such a town, by the advent of a plague infested
rat.
HOW TO IMPROVE SANITATION
1. Organize the community for better sanitation, and call in an
expert of the Public Health Service, which is giving a great deal of
NEEDS OF ENTOMOLOGICAL SANITATION IN AMERICA 89
attention to cooperative health work. In Russia, such organizations were
springing up all over the land before that country became submerged in
its present chaos.
2. Conduct a health publicity campaign.
3. Teach better sanitation in the schools and organize the children
for clean-up work.
4. Require the screening of all stores selling food, and of all hotels
and restaurants dispensing food. Do not allow food to be handled in
such a way that it will attract great quantities of flies.
5. Require private stables to place manure in fly-tight boxes and
to have same removed every 7 to 10 days.
6. Require livery stables to remove all accumulations of manure
daily from the town limits.
7. Require the burning, feeding or removal of all garbage twice a
week from homes and daily from hotels.
8. If garbage is hauled away and dumped the town should arrange
for its daily incineration.
9. Require throughout the town limits, depending upon conditions,
either sanitary plumbing and sewer connection, or sanitary box or pail
privies. Do not allow pit privies or insanitary ones of any type. Do
away as soon as possible with open sewer drainage, installing sewer pipe.
Install sewage septic tanks of size adequate for the town. If there are no
sewers laid it may be possible to arrange for individual installation of
simple septic tanks.
10. Do not allow pigs and chickens to have access to privies.
11. Do not permit general roving of pigs, stock, chickens, etc., on
the town streets.
12. Keep all ditches and waterways in the town free of obstruction,
and if mosquitoes are breeding, have an oiling squad.
13. Fix strict penalties against defecation on streets, alleys, and
vacant lots. ;
14. Install a town comfort station for strangers and people from
the country.
SANITARY PROBLEMS OF CITIES
The sanitary entomological problems are multiple in large cities, and
such that it would be an excellent practice to employ at least a consult-
ing entomologist in all large cities. As a matter of fact many cities
should have quite a corps of practical sanitary entomologists engaged
primarily for this type of work.
City markets where meats, fish and all kinds of vegetables and produce
are exposed for sale, are very attractive places for flies, and in many
large cities there is gross neglect along these lines.
40 SANITARY ENTOMOLOGY
Sanitary inspectors need to exercise considerable vigilance in checking
up obedience to ordinances relating to removal of trash, garbage, manure,
excreta; installation of sewage or sanitary privies; proper sanitation
among construction gangs; nuisances arising from stables, factories,
sewage and garbage disposal plants, packing houses, stock yards, etc.
Many manufacturing plants have waste products which are very attrac-
tive to insects. Insect conditions in restaurants, boarding houses and
hotels should be frequently checked up.
Anti-fly and anti-mosquito propaganda should be conducted annually
in every city until the people are so well educated to the necessity thereof
that propaganda will no longer be necessary.
The sanitary department of large cities should directly supervise
mosquito suppression within its bounds.
ENTOMOLOGICAL REQUIREMENTS OF MUNICIPAL SANITATION
The following points should be covered by ordinance in all large cities
desirous of obtaining satisfactory sanitation. Not enough attention
has been given by city health authorities to the insect side of their
sanitary problems.
1. All foodstuffs, which are eaten raw, all raw meats, fish, birds,
cooked foods, bread, cheese, dried fruits, etc., must be kept under cover
of glass or screen or otherwise protected from insects, in all markets,
stores, street stands, hotels, restaurants and boarding houses. Flies must
not be allowed to congregate around food stalls. Cockroaches must be
eliminated from all hotels, restaurants and boarding houses. Foods
infested by insects should be subject to condemnation and destruction.
Insect contamination of food is dangerous.
2. Hotels, public institutions, and lodging houses shall be required to
keep their premises free of bedbugs. Bedbugs carry disease.
8. All school children shall be inspected at the beginning of each
new school year for head lice, and oftener if circumstances warrant. In
case the children are infested they should be isolated and sent to some
clinic where they can be freed of the lice. All prisoners, patients in
hospitals, and applicants at municipal lodging houses should be in-
spected for head, body, and crab lice, and if infested should be bathed and
their clothing condemned or cleaned. Lice carry many diseases and every
opportunity should be taken which will enable the authorities to reduce
their incidence.
4, All livery stables shall be required to remove all manure to the
country daily, unless specified places for dumping are set aside. All
private stables should be provided with a fly-proof box or a maggot- |
i
\
NEEDS OF ENTOMOLOGICAL SANITATION IN AMERICA 41
trap platform for the storage of manure and should have the manure
removed at least every 10 days.
5. Garbage should be removed daily from all places where it accu-
mulates in large quantities, and two or three times a week from private
residences. All garbage awaiting removal should be kept in closed
cans. Garbage must not be dumped within the city limits unless it is
dumped on incinerators where fires will soon consume it. These require-
ments are necessary to keep down fly breeding.
6. Tin cans, bottles, and receptacles which will hold water, must
not be allowed to accumulate in back yards, alleys or vacant lots, nor
may they be dumped within the city limits or near residential sections
in the suburbs, because they furnish excellent breeding quarters for
mosquitoes.
7. The city should be connected for sewers as far into the suburbs
as practicable, and all suburban properties not so connected should be
required to install fly-proof cesspools, or septic tanks, or to arrange by
neighborhoods for independent sewage with a common septic tank; or in
the absence of water and necessary plumbing, to install sanitary privies,
and be required to have all excreta removed once a week to an incinerator
or other type of refuse disposal plant. Open vault privies-should not be
permitted in the city. Indiscriminate defecation on streets, alleys, vacant
lots, etc., should be strictly forbidden and punishable by law.
8. Packing houses, candy factories, syrup factories, and all other
manufacturing institutions producing food products should be required
to screen windows and entrances, and to use fly traps in such a way as
to minimize to the utmost the access of flies and other insects to the food
products. Especial attention should be given to the prevention of insect
breeding on such premises.
INDUSTRIAL SANITATION
Many industries have important entomological sanitary problems in
the preservation of their products from insect contamination and in the
efforts to conform to sanitary regulations. There are many times when
they would be able to use the services of a consulting sanitary entomologist
to advantage.
The keynote of industry today is the prevention or utilization of
waste. Insect depredations on food products cause waste because the
public does not want polluted food, and because sanitary inspectors are
becoming more and more alive to the menace to health from insect pol-
luted foods.
It is not generally understood that the presence of weevils and worms
in cereal foods may do more than destroy the food. The evidence is
42 SANITARY ENTOMOLOGY
growing against these insects from the sanitary standpoint. Some of
these insects contain substances in their bodies which are highly toxic, as
for instance Sitophilus granarius, the granary weevil, contains the
poisonous substance cantharidin. There are numerous instances of the
sickening of animals from eating weevily grain. Still more important is
the fact that where grain is accessible both to rodents and insects, certain
parasitic worms pass out in the feces of the rodent in the egg stage,
are eaten by the insect larvae in the grain, pass part of their life cycle
in the insect, and the insect is then possibly eaten by a rodent, in which
the worm completes its life cycle; or sometimes in our breakfast foods
we eat these parasitized insects and become infected with the worms. For
example, the rat tapeworm, Hymenolepis diminuta (Rudolphi) infests
various species of rats, but sometimes is found in man. Joyeux has
proved that its commonest intermediate host is the meal moth, Asopia
farinalis, which becomes infected by eating the tapeworm eggs, in the
larval stage. Grassi and Rovelli found the cysticercoid in the larva and
adult of this moth and also in the earwig, Anisolabis annulipes and the
beetles Akis spinosa and Scaurus striatus. Joyeux found that the adults
of the granary beetle, Tenebrio molitor, easily took up the eggs. A
cysticercoid or larval stage resembling the mouse tapeworm Hymenolepis
microstoma (Dujardin) has been found by Grassi and Rovelli in the
beetle Tenebrio molitor.
The whole problem, therefore, of the control of stored food product
insects is of vital importance to the manufacturers of food.
Syrup factories, sugar mills and refineries, ice cream factories, cream-
eries, and candy factories offer great attractions to flies which may
alight on the exposed products and deposit with their feet, or in their
vomit or excreta, germs of disease taken up elsewhere, perhaps days
before when the fly was a larva breeding in excrement, and these germs
may find the sweets excellent culture media for extensive growth. Extraor-
dinary means must be devised to keep flies away from such products.
Packinghouses offer abundant attractions to many kinds of insects,
many of which are serious disease carriers.
Railroad trains are the means of conveying from place to place
disease-carrying mosquitoes, flies, roaches, fleas, lice, bedbugs, and mites.
Fumigation of railway cars is an essential entomological control measure.
Dairies are often found to be the foci of the spread of typhoid fever,
and knowing the propensity of the house fly we can see how readily it
can carry the organisms from the stools of a sick person to the milk
pails in the dairy. There needs to be rigid control of flies in all dairies.
These are but examples of many industries which have problems in
sanitary entomology.
CHAPTER IV
A General Survey of the Seriousness of Insect-Borne Diseases to Armies ?
W. Dwight Pierce
As this course of study is directed primarily toward obtaining a
thorough knowledge of the relations of insects to diseases of men and
the measures which must be taken to prevent these diseases, it is eminently
proper for us to make a survey of the insect problems which confront the
greatest aggregations of men, the modern army. From a study of mili-
tary sanitation methods we may learn much which we need to know in
practical municipal problems. Military methods are based on the neces-
sity of quick returns and emergency efficiency, from which are built up in
permanent establishments more perfect measures.
The discussion of military entomology immediately falls into two very
distinct lines: first, the army training and concentration camps, and
second, the active service camps and battle conditions.
Before the location of the average training camp, we may assume
that it is possible to deliberate more or less on the desirability of one or
more sites and that in a general way drinking water and general health
conditions are considered. Not infrequently some other consideration
will outweigh sanitation, as when it is considered essential to place a camp
near a certain city or on a certain waterway or railway. In such cases
of expediency, we are quite likely to find sanitation a serious problem
from the outset.
The camp site is selected because of some important reason.
From an entomologist’s viewpoint a number of outstanding questions
immediately arise as to this site. Is the ground open or wooded, level or
sloping and well drained? Are there water holes, running streams, or
swamps in the camp area or nearby? Are there farmhouses, stables,
or other buildings on the site and what is the entomological situation in
these buildings? What disease-carrying insects are naturally breeding
about the camp site? If there has been any contagious disease of man
or animals in the community before the camp was located, the entomolo-
gist’s concern is the greater. He should if possible learn the focus of
1This lecture was originally presented May 27, 1918, and distributed the same day.
It has been revised for the present edition.
43
44 SANITARY ENTOMOLOGY
that disease and the insect conditions of that focus. The original health
conditions on the site may have a distinct bearing on later events.
Often the first arrivals at the camp site are contractors with multi-
tudes of laborers and animals collected from everywhere, and from every
stratum of society. There are few hygienic arrangements for these men.
In fact, the contractors are aiming to obtain as large profits as possible,
and therefore hold down the expenses for sanitary waste disposal. Some
among these laborers are almost certain to bring lice, bedbugs, fleas, and
possibly also scabies mites, on their bodies and clothes. Thrown together
indiscriminately in hastily constructed barracks, there is soon a general
distribution of vermin. Their animals are quite likely to be infected with
scabies mites and possibly other mites, and with bots and ticks. The
undisciplined assembling of many animals and carelessness about manure
disposal offers great attractiveness to all flics and insects attracted by
animals. It is probable that many dogs accompany the laborers and
contribute their quota of fleas. It is almost impossible with crude, unedu-
cated laboring men to get them to maintain sanitary conditions. Indis-
criminate defecation, the scattering of garbage, the accumulation of
manure, personal uncleanliness, all contribute to make contractor camps
sanitary sore spots. ‘
Sooner or later the sanitarians arrive on the spot, very likely with
a squad or company of raw untrained labor troops, and the clean-up
begins. We can expect a constant lack of coordination between the
military and the civilian. As for example, at one camp the sanitary
officers had constructed drainage ditches to carry off surplus standing
water, but the laborers persisted in throwing scraps of wood, underbrush
and waste into the ditches so that they were of no avail, or rather so that
they formed traps for water pools.
During the transition period when the camp is part civilian and part
military there will be two very different types of conditions existing
side by side, one good, one bad. Of course the army sanitarians have
supervision over these civilian camps, but they find difficulty in enforcing
sanitation. |
When a camp is placed like Camp Humphreys, Virginia, on a tongue
of land between two shallow bays of water that are known to fill up with
vegetation, and which furnish breeding places for millions of mosquitoes,
and with typical swamp lands at the heads of these bays, we may readily
see that the task of the sanitary officer is not an easy one. These bays
are moreover at tidal level and the daily fluctuations of the water add
complications to the drainage problem. Each individual camp, wherever
located, will present its own type of problems, and necessitates an early
and thorough entomological survey.
The tremendous speed of construction and the rapid arrivals of fresh
SERIOUSNESS OF INSECT-BORNE DISEASES TO ARMIES 45
contingents of troops and animals in a new army camp make the first
months of the entomological sanitarian very busy ones. Common sense
is one of the primary essentials in meeting the exigencies of the situation.
The possibility of mosquito breeding must be kept at a minimum in spite
of temporary drainage, multitudes of borrow pits, tree stumps, fire-water
barrels, etc. A system of manure, garbage, refuse, and fecal disposal
is of necessity hastily devised and must keep pace with the increasing
numbers of men and animals. This waste disposal is handled by special
units and the sanitarian acts only in an advisory capacity. He needs
therefore to be very vigilant in his inspections. Army camps nowadays
grow in such marvelous proportions that past experiences are of little
avail. The man on the ground must be well versed in the principles of
entomological sanitation and must use his judgment for all it is worth.
The constant accessions in troops and raw recruits call for constant
scouting and prophylaxis to prevent admission of vermin. The work
against vermin almost necessitates a specialist to take care of it alone. In
fact it were best if three entomologists were located in each camp, one
looking after the suppression of water and moist earth breeding insects,
one looking after the suppression of fecal, waste, and manure breeding
insects, and the third handling the vermin of the person and the barracks.
So serious is the vermin problem in all armies that elaborate measures
have to be taken to combat it. The Germans developed great vacuum
tubes that will contain an entire railroad coach. The Russians, and then
other nations, developed bath trains sufficient to handle the cleansing of
thousands of men a day. The Russians and Roumanians developed sod
houses for heat sterilization of clothing. Heat and steam sterilizing plants
of many types have been devised. A tremendous amount of experimen-
tation has been directed toward chemical cleansing of the clothing.
The destruction of waste is such an acute problem that many types of
incinerators have resulted (see figs. 1, 2, 3), but as a camp becomes
permanently organized the sewage system does away with many of the
early difficulties. Permanent incinerators, well kept drainage systems,
organized removal of the manure, and disposal of garbage by the quarter-
master’s department, systematic inspection of quarters and grounds, and
systematic bathing and cleansing of clothing, characterize the perfectly
adjusted sanitation of a permanent’ camp. Every large army camp
has its remount camp and company stables, The farther these stables are
located from the soldiers’ barracks the better will be the fly conditions
in the living quarters of the men.
The actively engaged army, however, presents entirely different con-
ditions. There is no possibility of developing sewage systems, but tem-
porary latrines must be substituted (see figs. 4, 5, 6, 7). Manure and
garbage cannot be farmed out to contractors, but must be disposed of
46 SANITARY ENTOMOLOGY
Fic. 1—Cross section of Mann’s hillside incinerator, used at U. S. Marine Camp,
Quantico, Va. (Mann).
dorbage
Fic. 2.—Modification of Mann’s hillside incinerator, adapting it to level ground (Mann).
eolid refuse
_semovable cots bars
\iquid refuse, can
eae
Fic. 3.—Small incinerator of the Ferguson type, for use of small units, and capable
of transportation (Mann).
SERIOUSNESS OF INSECT-BORNE DISEASES TO ARMIES 47
Fic. 4.—Straddle trench latrines, 1 foot wide, 2 feet deep, 3 feet long, for field opera-
tions at temporary locations (Mann).
==
=z in
=
—
=
SS
eo
=
=
=
2 aa}
Fie. 5.—Covered pit latrine level with ground, a semi-permanent type (Mann).
YL ZF
ee
Fig. 6.—Garbage can with top converted into portable urinal for use in company street
at night (Mann).
48 SANITARY ENTOMOLOGY
by hastily built incinerators, or the manure stacked and treated to kill
flies. Ditches and standing water cannot be drained. They must be
treated to kill insect life in them. Temporary hospitals abound and
must be protected from flies and vermin. The men sleep out of doors
or in scanty shelters, even in pig pens, barns, etc., wherever they can
find shelter in inclement weather.
Insect infestation in these must be reduced to a minimum. When lice
abound, hastily constructed devices must be installed or the clothing
treated by chemicals. The trenches and dugouts have to be sprayed with
creosote oils to keep away flies and kill vermin. Terrible stenches arise
from dead bodies and these must be buried or treated to prevent fly
breeding. In other words, everything here must be done hastily but
Fic. 7—Urine soakage pit, in cross section (Mann’s modification from Lelean).
effectively, for tomorrow the work may have to be done all over some-
where beyond or behind. The larger the body of men assembled and the
greater the carnage, the more serious the diseases of all kinds and
especially those carried by insects.
In the great European War the greatest diseases were those borne
by lice. In fact there is plenty of evidence that louse-borne diseases
have been among the worst in many wars of the past. Three serious
diseases which ravaged the trenches are carried only by lice,—typhus
fever, trench fever, and European relapsing fever. Millions of the
Serbian nation were wiped out by typhus fever. The Roumanian nation
was swept by typhus and relapsing fever. Russia, Germany, Austria and
France suffered terribly from these louse-borne diseases. Trench fever
spread back from the trenches into the cities. And yet all of these
diseases can be controlled absolutely by suppressing the lice. It is easy
to see how serious it is if a case of any of these diseases enters the
SERIOUSNESS OF INSECT-BORNE DISEASES TO ARMIES 49
trenches. The lice spread from man to man, and they are noted for
leaving a man with feverish conditions for a normal man.
Another disease which has been especially bothersome in the trenches
is scabies. Both horses and men are seriously afflicted with this mite
disease, and special veterinary hospitals were constructed in France solely
for handling horse scabies.
In malarious countries where mosquitoes are breeding in great num-
bers, malaria is a very serious camp and army problem. Campaigns in
tropical countries are endangered often by yellow fever, dengue and
filariasis, which are also mosquito-borne diseases.
The troops engaged in Asia and some parts of the Mediterranean lit-
toral had to contend with the possibilities of plague outbreaks. Troops
engaged in the African campaigns had to deal with trypanosome and
spirochete diseases. Along the Mediterranean littoral pappataci fever
is to be seriously considered. For example, a detachment of the British
Army in Egypt was suddenly attacked by an outbreak of this disease.
We are all familiar with the disaster of our Spanish-American War
in which so many thousands were carried away by typhoid fever, dysen-
tery and diarrhea, all fly-borne diseases. In the present war, to these
must be added Asiatic cholera, also borne by the fly.
The great quantity of carcasses on the battlefield gives rise to myriads
of flesh and carrion flies and as a consequence of the habit of these
flies of attacking wounds of living people, there were many cases of
human as well as animal anthrax in the European War.
These are only the more important army diseases carried by insects.
One of the greatest dangers to troops in active service lies in their
moving into countries with obscure or little studied diseases, or diseases
against which the men have had no chance to develop immunity,
CHAPTER V
Relation of Insects to the Parasitic Worms of Vertebrates 4
B. H. Ransom
The only important part insects are known to play in the propagation
of parasitic worms that affect human beings and other vertebrates is
that of true intermediate hosts necessary to the existence of the parasites
in some of their stages of development. Observations have been recorded
in the literature showing that flies and other insects may swallow the
eggs of various parasites of man such as hookworms, whipworms and
other nematodes in whose life history no intermediate hosts are required,
also the eggs of tapeworms in whose normal life history it is known that
insects are not concerned, for example, Taenia saginata, whose inter-
mediate host is the ox. It has been supposed that insects may thus act
as mechanical carriers for such parasites, but as a matter of fact definite
evidence of the importance of insects as mechanical carriers of the eggs
or larvae of parasitic worms has not yet been brought forth. On the
contrary there are reasons to suppose that in some cases at least the
swallowing of the eggs or larvae of parasites by insects that can act
only as mechanical carriers and not as intermediate hosts, reduces rather
than increases the chances of the young parasites continuing their
development and reaching a host in which they can become mature.
Among the parasitic worms affecting man and other vertebrates it is
those forms requiring intermediate hosts, so-called heteroxenous parasites,
that are of special interest so far'as insect transmission is concerned.
The monoxenous parasites, or those requiring no intermediate host, may
practically be left out of consideration, with the admission that the
mechanical carriage of monoxenous parasitic worms by insects may in
the future be proved to have an importance not yet demonstrated.
A complete demonstration of the part played by an insect in the life
history of a given species of parasite is often a difficult matter. The
animal which serves as the final host may be subject to infection not
only with the species of parasite under investigation but also with other
species liable to be confused with it in some of its stages. The insect
1This lecture was read to the class on December 16, 1918, and distributed January,
1919. It has been revised up to date. The names of insects have been revised by
the editor.
50
RELATION OF INSECTS TO THE PARASITIC WORMS 51
may likewise harbor parasites other than the one that is being studied.
The possibilities of confusion and of the entrance of extraneous factors
into the problem are so many and so varied that in most cases it is
only after the most rigorously controlled experiments, combined with
careful comparative studies of the successive stages of the parasite, that
conclusions may safely be drawn. Furthermore, in working out the life
history of a parasitic worm it is not sufficient to prove that insects of a
certain species can act as intermediate hosts under experimental condi-
tions. Some species of parasitic worms are able to develop in more than
one species of insect, and the fact that a certain parasite can develop in
a certain insect does not necessarily mean that under natural conditions
the species of insect in question serves as the intermediate host of the
parasite. For example, one of the common parasites of sheep and cattle
is able to pass through its larval stages in cockroaches. These insects
become readily infected if the eggs of the parasite which occur in the
feces of the final host animals are fed to them. Under natural conditions,
however, cockroaches do not ingest the feces of sheep and cattle, nor are.
they found in places where they are likely to be picked up by sheep and
cattle. Besides cockroaches, various species of dung beetles have been
shown to be capable of acting as intermediate hosts of the parasite in
question, and it is evident that these insects are the natural intermediate
hosts. Unlike cockroaches they have plenty of opportunity both of
becoming infected and of passing on their infection to the final hosts.
A more or less intimate environmental relationship between the insect
host and the final host generally exists in the case of parasites transmitted
‘by insects. In a number of cases the insects are coprophagous and also
likely to be ingested by the final hosts, as in the instance just cited.
Another highly interesting group of cases is that in which the insects
are ectoparasites on the final hosts, or bloodsuckers that periodically
visit them, and thus have particularly favorable opportunities for becom-
ing infected with parasitic worms harbored by the animals they attack
and in turn reinfecting the latter.
MODE OF INFECTION OF INSECT HOSTS
As already stated the part which insects may take in the propagation
of parasitic worms of higher animals is that of intermediate hosts, in
which certain larval stages of the parasites are passed before they are
ready to enter the bodies of their final or definitive hosts in which they
develop to maturity. The way in which the insects become infected varies
with different species of parasites. In the case of some species which
live in the alimentary tract of the final host the eggs or larvae are dis-
charged from the. body of the host in the feces. Coprophagous insects
52 SANITARY ENTOMOLOGY
swallow the eggs and if they are suitable intermediate hosts for the
parasites the young worms go through several developmental stages and
finally within the bodies of the insects reach a stage in which they are
ready to be introduced into the body of the final host. Certain parasites
whose adult stages live in relation with the blood vessels of the final host
discharge their young into the blood stream whence they may be ingested
by bloodsucking insects in whose ‘bodies they undergo development to a
stage infective for the final host. Aquatic insects may swallow free-living
larval stages of parasites, or may be actively attacked by larval para-
sites which gain entrance to their bodies by penetrating the cuticle.
These insects may in turn be eaten by other insects and the infection thus
passed on to them.
In some cases the parasites may be taken up by insects or enter
their bodies during an early stage of development of the insects and
persist in later stages. Infection may thus occur during one stage of the
insect but the development of the parasite to a stage infective for the
final host may not be completed until after the insect has reached a later
stage. Thus flies become infected with a certain parasite of the horse
during the maggot stage, but the young parasites do not become suffi-
ciently developed to be returned to the final host until the flies have
reached the pupal or adult stage.
MODE OF INFECTION OF VERTEBRATE HOSTS
Parasitic worms that have insects for intermediate hosts reach
their final hosts in various ways. In the case of some species the insect
hosts are swallowed either as the habitual food of the final hosts, or
incidentally with food or drink. In other instances the young worm may
have already escaped from its insect host before it is taken in with food
or drink by its final host. The cases of accidental infection with horse-
hair worms not normally parasites of human beings are likely to have
happened in this way. The parasites of which bloodsucking insects are
intermediate hosts may be introduced into their final hosts as a result of
the escape of the larval parasites from the insects at a time when the
insects are drawing blood. Commonly the larve burst through a weak
spot in the cuticle of the insect and then burrow into the skin of the
final host.
SPECIES OF WORMS FOUND IN INSECTS
The parasitic worms of the higher animals in whose life history insects
and insect-like organisms play a part, belong to two large zoological
groups, Plathelminthes and Nemathelminthes. The former may be sub-
divided so far as concerns parasitic forms into Cestoda, or tapeworms,
RELATION OF INSECTS TO THE PARASITIC WORMS 53
and Trematoda, or flukes; the latter into Nematoda, or roundworms in
the restricted sense, Gordiacea, or horse-hair worms, and Acanthocephala,
or thorn-headed worms.
CESTODA OR TAPEWORMS
All tapeworms whose life history has been well established require an
intermediate host, and are thus heteroxenous parasites. A typical life
history of a tapeworm is as follows: The adult lives in the intestine of
the final host. The eggs pass out of the body of the infested animal in
the feces. The feces or food or drink contaminated by them are swallowed
by an animal that can act as an intermediate host. The eggs thus
reaching the intermediate host hatch in the alimentary tract and the
embryos set free migrate into nearby or remote tissues of the body,
developing finally into an intermediate stage, commonly of the type known
as a cysticercoid, in the case of those tapeworms whose intermediate stages
occur in insects. Having reached this stage further development of
the parasite awaits the time when the intermediate host or infested por-
tions of its body are swallowed by an animal that can act as the final host,
whereupon it resumes its development and, becoming mature, completes
the life cycle. About 100 species of tapeworms are known whose adult
stages occur in man or domestic animals. Four of these, Dipylidium
caninum (the double-pored tapeworm of the dog, cat, and man), Hymen-
olepis diminuta (the yellow-spotted tapeworm of rats, mice, and man),
Hymenolepis nana (the dwarf tapeworm of rats, mice, and man), and
Choanotenia infundibulum (one of the tapeworms of the domestic fowl),
have insects as intermediate hosts, with the possible exception of the dwarf
tapeworm, in whose life history the part played by insects has not been
definitely determined.
Dipylidium caninum (Linneus, 1758) Railliet, 1892
This tapeworm, sometimes called the double-pored dog tapeworm, is of
very common occurrence in the small intestine of dogs and cats, and of
occasional occurrence in human beings. Its larval stage (cysticercoid)
occurs in the biting dog louse [T'richodectes latus (canis)] as deter-
mined experimentally by Melnikov (1869), and in fleas (Ctenocephalus
canis, C. felis, and Pulex irritans). Fleas apparently are the usual
intermediate hosts. Grassi and Rovelli (1888, 1889) followed the various
stages of laryal development in adult fleas, from the hexacanth embryo
to the fully developed cysticercoid, and as they failed to find the parasite
in larval fleas concluded that only adult fleas can act as hosts. Recently,
however, Joyeux (1916) has reached the conclusion that adult fleas
54 SANITARY ENTOMOLOGY
are unable to swallow the eggs of the tapeworm. He finds that larval
fleas readily swallow the eggs; these hatch in the intestine of the insect,
and the embryos thus released penetrate into the body cavity. They per-
sist in the hexacanth stage until the transformation of the flea into the
adult, after which they proceed with their development and in a short
time reach the cysticercoid stage. Infection of the dog, cat, or human
being occurs naturally as a result of swallowing infested fleas. Fleas
are exposed to infection owing to the fact that their larve live in an
environment likely to be contaminated by the feces of infested dogs or
cats. The eggs of the tapeworm as passed in the feces are grouped in
capsules containing about a dozen eggs, so that infection of the insect
host is likely to be multiple. The double-pored tapeworm is relatively
uncommon in man and most of the cases recorded, of which there have been
less than 100 all told, three in the United States, are among young
children. Children are more likely than adult human beings to swallow
fleas, which would explain the greater frequency of infestation among
children. Another possible explanation of the more common occurrence
of this parasiteeamong children than among adults is that older persons
may possess a greater immunity to infection. Prophylaxis against the
double-pored tapeworm consists chiefly in keeping dogs and cats free from
lice and fleas, and so far as human beings are concerned excluding dogs
and cats, especially if they are lousy or infested with fleas, from human
habitations.
Hymenolepis diminuta (Rudolphi, 1819) Blanchard, 1891
Hymenolepis diminuta (the yellow-spotted tapeworm) is of frequent
occurrence in the small intestine of rats and mice, particularly the former,
and of occasional occurrence in the intestine of man. The adaptability
of the adult tapeworm to hosts so widely different as rodents and human
beings is paralleled by the adaptability of the larval stage to various
intermediate hosts. Cysticercoids belonging to this species have been .
recorded in various insects, a Lepidopteron, Asopia farinalis, in both
larva and imago; a Dermapteron, Anisolabis annulipes; Coleoptera, Akis
spinosa, Scaurus striatus, and Tenebrio molitor; and fleas Ceratophyllus
fasciatus, Xenopsylla cheopis, Pulex irritans, and Ctenocephalus canis;
also in myriapods, Fontaria virginiensis and Julus sp. Nicoll and
Minchin (1911) found the cysticercoids in about 4 per cent of the rat
fleas (8 out of 207) they examined during a period of thirteen months,
and they succeeded in infecting rats with the tapeworm by feeding them
fleas, as Grassi and Rovelli (1892) had previously done by feeding other
insects. Joyeux (1916) infected the larvae of Asopia farinalis by feeding
the eggs of H. diminuta and believes the cysticercoids recorded in the
RELATION OF INSECTS TO THE PARASITIC WORMS _ 55
adult moth by Grassi and Rovelli were carried over from the larval stage
of the insect. He failed in his attempts to infect Forficula auricularia,
Blatta orientalis, and Blattella germanica. He also failed to infect
beetles belonging to the species Blaps mortisaga, but succeeded easily in
infecting the adults of Tenebrio molitor. The larve of this latter beetle
according to Joyeux are incapable of acting as intermediate hosts of
H. diminuta. He was able to infect the larve of rat fleas and of Pulex
irritans and Ctenocephalus canis. In these insects the embryos of H.
diminuta begin immediately to develop into cysticercoids and do not wait
for the transformation of the larval fleas into adults, as Joyeux found in
the case of Dipylidium caninum, the embryos of which apparently lie
dormant in the insect until after it transforms into the adult stage. In
this country Nickerson (1911) has reared the cysticercoid in myriapods,
Fontaria virginiensis and Julus sp., fed on the eggs of the tapeworm. He
failed in his attempts to infect meal worms.
It is evident that infection of the definitive host with H. diminuta
results from swallowing infested insects, the latter having become infested
as a result of swallowing the eggs contained in the feces of animals harbor-
ing the tapeworms. As a parasite of man in the United States, so far as
available statistics show, H. diminuta ranks about third in frequency
among the tapeworms, the beef tapeworm (Twnia saginata) being the
most common, and the dwarf tapeworm (H. nana) being next. Evident
prophylactic measures are those directed toward the destruction of rats
and mice and the avoidance of the ingestion by human beings of the
various insects that may serve as intermediate hosts, especially the pro-
tection of farinaceous foods from insect infestation.
Hymenolepis nana (Siebold, 1852) Blanchard, 1891
Hymenolepis nana (the dwarf tapeworm) is a very common intestinal
parasite of rats and mice and is of rather frequent occurrence in man,
especially in children. In the United States it ranks second to the beef
tapeworm in the order of frequency among the tapeworms of man. Its
life history has not been fully worked out. Grassi (1887), however, has
found that cysticercoids develop in the intestinal villi of rats that have
been fed the eggs of the dwarf tapeworm. According to his view the
cysticercoids later break out of the villi into the lumen of the intes-
tine and grow into mature tapeworms. The rat thus acts both as inter-
mediate and definitive host of the dwarf tapeworm, the parasite being
spread from one rat to another through the medium of the eggs passed
in the feces. The dwarf tapeworm, according to Grassi’s version of the
life cycle, is an exception to the rule among tapeworms that the adult
-stage occurs in one species of animal and the larval stage in another
56 SANITARY ENTOMOLOGY
species likely to be eaten by animals of the species that harbors the
adult tapeworm.
Inasmuch as Nicoll and Minchin (1911) have found cysticercoids in
a rat flea (Ceratophyllus fasciatus) that in details of head structure are
apparently exactly similar to and specifically identical with the dwarf
tapeworm, the question arises whether such insects may not act as inter-
mediate hosts, and whether in addition to the life cycle of an exceptional
type described by Grassi, the dwarf tapeworm also has a life cycle of
the ordinary type. T. H. Johnston has found cysticercoids similar to
those recorded by Nicoll and Minchin in another species of rat flea
(Xenopsylla cheopis) as well as in Ceratophyllus fasciatus.
Joyeux (1916) has failed in experiments with fleas belonging to the
species named and to related species, to infect them with H. nana. He
states he used both larval and adult fleas. On the other hand he was able
to confirm Grassi’s results and succeeded in infecting a large number of
rats and mice by feeding them the eggs of the tapeworm. The experi-
mental evidence thus far available accordingly favors the view that insects
do not play a necessary part in the life history of the dwarf tapeworm.
Furthermore, considering the frequency of occurrence of H. nana as
a parasite of man, and the enormous numbers of the parasites sometimes
present, it would seem that infection is more likely to occur in the manner
described by Gragsi than as a result of swallowing rat fleas, there being
of course a greater likelihood of human beings swallowing rat feces or
fecal matter from other human beings containing large numbers of eggs
of the tapeworm than of swallowing rat fleas containing a sufficient num-
ber of cysticercoids to develop into the large number of tapeworms that
have been found in some cases.
Choanotenia infundibulum (Bloch, 1779) Cohn, 1899
Choanotenia infundibulum is a common tapeworm of chickens in
various parts of the world. Grassi and Rovelli (1892) in Italy found
cysticercoids in the common house fly (Musca domestica) which on
account of their morphological similarity to Choanotenia infundibulum
they inferred belonged to this species. From the results of experiments
conducted in this country by Guberlet (1916) it appears safe to conclude
that the common house fly acts as the intermediate host of the tapeworm,
Choanotenia infundibulum, infection of the fly apparently occurring as
a result of swallowing the eggs of the tapeworm, and the chicken in turn
acquiring the parasite as a result of swallowing flies infested with the
cysticercoid stage. Whether infection of the fly reg ularly occurs during
the larval or during the adult stage, or during both stages, has not been
definitely settled.
RELATION OF INSECTS TO THE PARASITIC WORMS 57
Prophylaxis in the case of this tapeworm is obviously largely
dependent upon fly control measures.
Other Tapeworms
According to Villot (1883) the larval tapeworm observed by Stein
(1852) in the larva of Tenebrio molitor belongs to the tapeworm of the
mouse, known as Hymenolepis microstoma. The same writer (1878,
1883) also associates with certain tapeworms of shrews, two species of
larval tapeworms which he found in myriapods, Glomeris limbata. Fur-
ther investigations of these parasites appear necessary to substantiate
the views held by Villot as to their specific identity. Ackert (1918, 1919)
has recently recorded some experiments in which chickens were given
house flies and became infested with tapeworms (Davainea cesticillus and
D. tetragona). The immature stages of these parasites were not, how-
ever, seen in the flies and the possibility is not excluded that the chickens
became infected from some source other than the flies, notwithstanding
the precautions taken against extraneous infection. Guberlet (1919)
caught stable flies (Stomoxys calcitrans) in poultry yards where the
chickens were commonly infested with Hymenolepis carioca (Magalhiaes,
1898) and fed them to young chicks with the result that some of them
became infested with this tapeworm. He concludes that the stable fly
possibly serves as an intermediate host of this tapeworm.
TREMATODA OR FLUKES
All species of flukes whose life history is known depend upon molluscs
as hosts for certain larval stages, and they may or may not require one
or more additional intermediate hosts before they reach the definitive host.
It is as intermediate hosts following the first intermediate host, a mollusc,
that insects can play a part in the propagation of flukes. As yet it has
not been shown that insects are concerned in the life history of any of
the flukes (about 100 known species) that affect human beings or domestic
animals, but as the life history of all of these parasites has not been
determined it is quite likely that in the case of some species insects will be
found to act as intermediate hosts. Different species and groups of
species show various types of life history with reference to the number
of larval stages through which the parasite passes and the number of
intermediate hosts required. A comparatively simple life cycle is as
follows: ‘The mature fluke in the definitive host produces eggs which pass
to the exterior inthe feces. Under suitable conditions of moisture and
temperature the egg hatches and a ciliated larva, the. miracidium, issues.
If this miracidiwm finds a suitable mollusc (different species of molluscs
58 SANITARY ENTOMOLOGY
attract different species of miracidia) it burrows into the soft tissues of
the mollusc and reaching the respiratory chamber proceeds to develop
into the next stage, the sporocyst. Within the sporocyst by a process
of internal budding more or less numerous so-called rediw develop. The
rediz finally leave the sporocyst and migrate into the liver of the mollusc.
In the redia several generations of daughter redie may develop by
budding. The next stage, developed also by internal budding from the
redia, is the cercaria. The cercaria of some species is provided with a
tail by means of which it swims about in the water when it finally escapes
from the mollusc. The cercaria may be swallowed by or actively pene-
trate into some animal and become encysted in this animal. Finally when
the animal harboring encysted immature flukes is swallowed by an animal
which can serve as a host of the adult fluke, the young flukes thus reach-
ing their definitive host develop to maturity and the life cycle is complete.
Following is given a partial list of the insects in which young flukes
have been recorded. The species to which the young flukes in question
have been assigned and the final host animals are also indicated. Further
investigations are likely to show that some of the flukes from insects
have been misidentified and do not belong to the species to which they
have been supposed to belong, and the data given in the list should
not be accepted as fully proved in any case, though there can be no doubt
in some of the cases cited. No distinction has been made between certain
and doubtful cases, except that a few that are doubtful are indicated by
question marks. The determination of species of young flukes found in
insects has generally been made solely upon their morphological similarity
to adults occurring in vertebrate hosts and it is quite likely that mistakes
have been made by investigators of these parasites just as mistakes have
frequently been made in the association of immature and adult parasites
belonging to other groups of worms.
NEMATODA OR ROUNDWORMS
Among parasitic worms the species of nematodes are more numerous
than either the species of tapeworms or flukes. Nematodes as a group
are not exclusively parasitic and thousands of free-living species are
known to exist, although comparatively few have been described. Many
species of nematodes are parasites of insects only and do not occur in
other animals. Insects therefore harbor parasitic nematodes which belong
to them exclusively as well as the larval stages of nematodes that occur
in higher animals in their adult stage. The ubiquity of free-living nema-
todes introduces a frequently troublesome complication into the study
of the life histories of monoxenous parasitic nematodes of which there
are many species, and the common occurrence of parasitic nematodes
RELATION OF INSECTS TO THE LIFE CYCLE OF FLUKES
Insect Host Adult Fluke, Final Host
Coleoptera
Ilybius fuliginosus (Fabricius) (adult) Haplometra cylindracea Frogs
Water beetle (larva) Prosotocus confusus
iB = “ Pleurogenes medians f
ss * - ie claviger "
Lepidoptera
Nymphula nympheata (Linnzus) (larva) Unknown Unknown
Diptera
Anopheles maculipennis Meigen (claviger Fa-
bricius) (adult) sé es
Anopheles rossi Giles (adult) ss ae
Chironomus plumosus Linneus (larva) Lecithodendrium ascidia Bats
Culex quinquefasciatus Say (fatigans Wiede-
mann) (adult) Unknown Unknown
Trichoptera
Anabolia nervosa (Leach) Curtis Allocreadium isoporum Cyprinoid
fishes
Anabolia nervosa (larva) Opisthioglyphe rastellus Frogs
Cheetopteryx villosa (Fabricius) (larva) Allocreadium isoporum Cyprinoid
fishes
Drusus trifidus McLachlan (larva) Unknown Unknown
Limnophilus rhombicus (Linnzus) (larva) Opisthioglyphe rastellus Frogs
griseus (Linnzus) (larva) cs c cs
“e lunatus (Curtis) (larva) Bi sé
ee flavicornis (Fabricius) (larva) aS ee i
Mystacides nigra (Linnzus) (larva) Unknown Unknown
Notidobia ciliaris (Linneus) (larva) ss “
Phryganea sp. Lecithodendrium chilostomum | Bats
Phryganea grandis (larva) Unknown Unknown
Rhyacophila nubila Zetterstedt (larva) s Bats
Neuroptera
Sialis lutaria (Linneus) (larva) 8 Unknown
Odonata
A:schna (larva and adult) Prosotocus confusus Frogs
Agrion (larva) Gorgodera pagenstecheri Wa
ge ee varsoviensis es
= Pleurogenes medians ss
Calopteryx virgo (Linnzus) Halipegus ovocaudatus e
“4 “(larva and adult) Pneumoneeces similis. ee
Cordulia (larva) Prosotocus confusus ig
Epitheca “ Gorgodera cygnoides __ se
ae “ i pagenstecheri ee
“ “s ss varsoviensis oi
’ Plectoptera sd a
Cloeon dipterum (Linnzus) Stephens (larva) |?Opisthioglyphe rastellus aieares
Ephemera vulgata Linneus (larva) Allocreadium isoporum Cyprnoid
shes
co 8 * ?Opisthioglyphe rastellus Frogs
Ephemeridz (larva) Lecithodendrium ascidia Bats
Plecoptera ; : Ree i
Perlide (larva) Lecithodendrium ascidia
“ “ Unknown Unknown
59
60 SANITARY ENTOMOLOGY
among insects introduces an equally troublesome complication into the
study of the life histories of the heteroxenous nematodes parasitic in
higher animals, for which insects may serve as intermediate hosts. About
250 species of nematodes have been recorded as parasites of man and
domestic animals. Many of these require no intermediate hosts, but
some are heteroxenous parasites, and a number of these are known to have
intermediate stages in insects and closely related arthropods. In the
following discussion, in addition to the nematodes parasitic in man and
domestic animals, certain species parasitic in other animals are also con-
sidered because of the part played by insects in their life history. For
convenience they may be placed in two groups, (1) those in which the
eggs or first-stage larve leave the body of the final host in the feces, and
(2) those in which the first-stage larve occur in the blood or lymph of
the final host and leave the body through ingestion by bloodsucking
insects.
1. Parasitic Nematodes Whose Eggs or Larve Leave the Body of the
Final Host in the Feces
Protospirura muris (Gmelin, 1790) Seurat, 1915
This nematode, parasitic in its adult stage in the stomach of various
species of rats and mice, is of special interest historically as being the
first parasite in whose transmission to its final host an insect was found
to be concerned. Stein in 1852 recorded the presence of encysted nema-
todes in the larve of meal beetles (Tenebrio molitor). WLeuckart (1867)
and Marchi (1867) fed eggs of Protospirura muris (Spiroptera obtusa)
to meal beetle larve and followed the development of the young nematodes
up to the encysted stage found by Stein. This development is completed
in about six weeks after ingestion of the eggs. The development to the
adult stage was also followed in mice fed with the encysted nematodes from
meal worms. Johnston (1913) has recorded encysted nematode larve
which appeared to him identical with those of P. muris in the body cavity
of a rat flea (Xenopsylla cheopis ). :
Spirocerca sanguinolenta (Rudolphi, 1819) Railliet & Henry, 1911
The adults of this nematode live in tumors of the stomach and
esophagus of the dog and the wolf. The eggs-unhatched pass out of the
body of the dog in the feces. Grassi (1888) found encysted larval nem-
atodes in cockroaches (Blatta orientalis) which he suspected were the
larve of S. sanguinolenta. Dogs fed with these encysted nematodes after
five days showed the larve free in the stomach; after ten days the young
worms were further developed and were firmly. attached to the mucosa
RELATION OF INSECTS TO THE PARASITIC WORMS 61
of the esophagus; and after fifteen days they had sunk themselves into
the wall of the esophagus and had developed still further. Grassi con-
cluded that cockroaches act as intermediate hosts, swallowing the eggs in
the feces of infested dogs, and*in turn being swallowed by dogs. Seurat
(1913), however, believes that Grassi was mistaken as to the identity of
the encysted nematodes found in the cockroaches, and that they were
really the larve of Spirura gastrophila, the adult of which occurs in the
stomach of the cat, hedgehog (Erinaceus algirus ), and fox (Vulpes vulpes
atlantica). Seurat (1912, 1916) finds what he considers to be the larve
of S. sanguinolenta encysted in a great variety of animals including
beetles, reptiles, birds, and mammals. The presence of the encapsulated
larve in various vertebrates he explains as the result of the ingestion of
insects infested with the larve. If the vertebrate is not a host in
which the parasites can continue their development as they would in
their normal host the dog, they migrate into the wall of the alimentary
tract or mesentery and become reencysted without further development.
If, however, the infested insect is swallowed by a dog the larve, after
they have been freed by digestion of the cysts surrounding them, continue
their development and finally reach maturity. Seurat in fact found
that encysted larve in insects identified as those of S. sanguinolenta when
fed to mice became reencysted in the manner described. Seurat (1916)
records the following insects as hosts of the larve of §. sanguinolenta, all
of them beetles: Scarabeus (Ateuchus) sacer, Scarabeus (Ateuchetus )
variolosus, Akis goryi, Geotrupes douei, Copris hispanus, and Gymno-
pleurus sturmi. According to Seurat the life cycle of S. sanguinolenta
would be as follows: The eggs pass out of .nfested dogs in the feces,
are ingested by beetles, hatch, and the larve after a period of growth and
development become encysted. If infested insects are swallowed by dogs
or wolves the larval worms are released from their capsules and develop to
maturity. If the insects are swallowed by other animals, the larve may
become freed from their cysts as in the alimentary tract of the dog,
but they are unable to develop further and leave the lumen of the
alimentary tract and become reencysted in the tissues to which they
migrate. In such a case, of course, there is a possibility of their resuming
their development if the infested animal should afterwards be devoured by
a dog or a wolf, but this possibility apparently has not yet been sub-
stantiated.
Spirura gastrophila (Mueller, 1894) Marotel, 1912
This nematode in the adult stage occurs in the stomach and the lower
end of the esophagus of the cat. It has also been recorded by Seurat
(1913) from the stomach of a hedgehog (Erinaceus algirus) and the
stomach and esophagus of a fox (Vulpes vulpes atlantica), and by the
62 SANITARY ENTOMOLOGY
same author (1918) in the esophagus of the mongoose (Herpestes
ichneumon). This author identifies certain encysted larval nematodes
found in a species of Onthophagus, in Blatta orientalis, in Blaps strauchi,
and in Blaps sp. (near appendiculata) as belonging to 8. gastrophila.
He thinks the parasites found in the cockroach and called Filaria ryti-
pleurites by Deslongchamps (1824), and those identified as such by Galeb
(1878) who associated them with an insufficiently described adult
nematode of the rat, are probably the same as those he identified as the
larve of S. gastrophila. He also dismisses Grassi’s experiments as insuffi-
cient to show that the nematodes encysted in cockroaches are the larve
of Spirocerca sanguinolenta as Grassi believed, and concludes that Grassi
was mistaken and was really dealing with the larve of Spirura gastrophila.
Seurat (1919) adds Akis goryi to the list of insect hosts of the larve of
S. gastrophila,
Gongylonema scutatum (Mueller, 1869) Railliet, 1892
This nematode in the adult stage is a common parasite in the mucous
membrane of the esophagus of cattle, sheep, and other ruminants, and
has also been recorded from the horse. Ransom and Hall (1915, 1916,
1917) have shown that various species of dung beetles (Aphodius
femoralis, A. granarius, A. fimetarius, A. coloradensis, A. vittatus,
Onthophagus hecate, and O. pennsylvanicus) act as intermediate hosts.
Experimentally, cockroaches (Blattella germanica) can also be made to
serve as intermediate hosts, a part of course which they do not play
under natural conditions. The eggs_of the parasite pass out of the body
of the definitive host in the feces and are swallowed by dung beetles. They
hatch in these insects, and the larve entering the body cavity undergo a
certain growth and development, reaching their infective stage in about
a month, meanwhile becoming enveloped in capsules in which they lie in
a coiled-up position. Further development waits upon the swallowing of
the infested insect by a cow, sheep, or other suitable host as may readily
occur while the animal is grazing, the insect being ingested with the herb-
age upon which it happens to be. Following their ingestion by the defini-
tive host, the larve are released from their capsules and develop to matur-
ity. Seurat (1916) has described some larval nematodes from the abdom-
inal cavity of Blaps strauchi, Blaps appendiculata, and Blaps sp. (near
appendiculata) in Algeria that he identifies as Gongylonema scutatum.
As pointed out by Ransom and Hall (1917), however, these evidently
belong to another species as they do not correspond to the forms shown
by these writers to be the larve of G. scutatum. Seurat (1919) adds
Blaps emondi to the list of insects in which he has found the larve
in question.
RELATION OF INSECTS TO THE PARASITIC WORMS 63
Gongylonema mucronatum Seurat, 1916
This nematode occurs in the adult stage in the mucosa of the esophagus
of the Algerian hedgehog (Erinaceus algirus). According to Seurat
(1916) its larval stage is found encapsuled in the body cavity of various
species of coprophagous beetles, Ateuchus sacer, Chironitis irroratus,
Onthophagus bedeli, Gymnopleurus mopsus, Gymnopleurus sturmi, and
Geotrupes douei, but there appears to have been some confusion as to
the identity of the larve in question, and further investigation of the life
history of this species is desirable (Ransom and Hall, 1917).
Gongylonema brevispiculum Seurat, 1914
Seurat (1916), in addition to forms found in different species of Blaps
that he considers to be third stage larve of Gongylonema scutatum, has
described as second stage larve of G. scutatuwm some larval nematodes
found encysted in the abdominal cavity of Blaps sp. and Blaps straucht
in certain localities in Algeria. In a later paper, however (1919), he
has expressed the opinion, based upon the morphology of the worms and
a knowledge of the mammalian fauna in the region in which the parasites
are found, that these larve are third stage larve and belong to the species
G. brevispiculum the adult of which occurs parasitic in the cardiac portion
of the stomach of a species of jerboa (Dipodillus campestris ).
Further investigation seems desirable as to the identity of the supposed
larve of Gongylonema brevispiculum as well as of the other larve of
Gongylonema that have been assigned to various species on a basis of
apparent morphological similarities and general considerations. A con-
tinuation of the excellent work already done by Seurat relating to the
larval forms of Gongylonema will no doubt clear up the confusion that
now exists.
Gongylonema neoplasticum (Fibiger and Ditlevsen, 1914) Ransom and
Hall, 1916
rs
This nematode occurs in the adult stage in the mucosa of the stomach,
esophagus and mouth of the rat. It has been reared experimentally
in the rabbit and guinea pig as well as in the rat and mouse. It is of
special interest from the medical standpoint because it is commonly
associated with and perhaps stands in etiological relationship to gastric
carcinoma of rats. Fibiger and Ditlevsen (1914) have proved that cock-
roaches (Periplaneta americana, Blatta orientalis, and Blattella german-
ica), and a grain beetle (Tenebrio molitor) can act as intermediate hosts.
The eggs are passed in the feces of infested rats and if ingested by one
%
\
64 SANITARY ENTOMOLOGY
of the insects named will hatch, the larve within twenty days after
ingestion of the eggs developing to the infective stage. In this stage the
larve are coiled up in cysts in the muscles of the prothorax and legs,
differing in location from the larve of G. scutatum which in artificially
infected cockroaches, as in their normal hosts, dung beetles, are found
encysted in the body cavity.
Arduenna strongylina (Rudolphi, 1819) Railliet and Henry, 1911
This nematode in its adult stage occurs in the stomach of the pig.
Seurat (1916) has recorded the presence of larval nematodes in the
stomach of a pig associated with adults of 4. strongylina which he con-
siders belong to this species. He has found morphologically similar larval
nematodes encapsuled in the body cavity of Aphodius rufus castaneus and
states that they also occur in beetles of the genus Onthophagus. Ap-
parently no feeding experiments have been carried out. Presumably the
life history would be similar to that of Gongylonema scutatum, Proto-
spirura muris, etc., that is, the eggs of the parasite passed in the feces are
swallowed by beetles, the larve develop in these insects to the infective
stage, and are transferred to the definitive host when the beetles are
swallowed by a pig, after which the young worms complete their develop-
ment to maturity. Seurat (1919) records the presence of encysted larve
of A. strongylina in the stomach wall of the Algerian hedgehog (Erimaceus
algirus). Apparently, therefore, the larve of this species that occur
encysted in insects, like those of Physocephalus seralatus and Spirocerca
sanguinolenta, if ingested by vertebrates other than the normal hosts of
the adult worms, migrate out of the lumen of the digestive tract and
become reencysted in the neighboring tissues.
Physocephalus sexalatus (Molin, 1860) Diesing, 1861
The adults of this nematode live in the stomach of the pig, dromedary,
and donkey. Seurat (1913) has found two successive larval stages pre-
ceding the adult in the stomach of the definitive host (donkey) and has
also (1916) established the common occurrence of the earlier of these two
stages in various dung beetles (Scarabeus [Ateuchus] sacer, S.
[Ateuchetus] variolosus, Geotrupes douei, Onthophagus nebulosus and
O. bedeli). Pigs of course are commonly known to be coprophagus in
their feeding habits and Seurat states that the donkeys of Algeria, where
his investigations were made, commonly devour fecal matter swarming
with dung beetles. The way in which the larve of P. seralatus reach their
final host is therefore evidently through the ingestion of infested beetles
by pigs, donkeys, or dromedaries. Presumably of course the beetles be-
RELATION OF INSECTS TO THE PARASITIC WORMS 65
come infested by eating the eggs of the parasite which are passed in the
feces of infested pigs, donkeys, and dromedaries. As in the case of
Spirocerca sanguinolenta Seurat finds encysted larve of P. seralatus in
various vertebrates in Algeria, particularly reptiles and insectivores.
Their presence in these animals he would explain in the same way as he
explains the presence of the encysted larve of S. sanguimolenta in such
animals, that is, the larve present in insects devoured by the animals in
question are unable to continue their development as they would in pigs
and other suitable hosts. On the other hand they do not succumb in their
strange environment nor do they pass through the alimentary tract with
the feces but penetrate into the walls of the stomach and into other tissues
and become reencysted, surviving in this condition more or less indefinitely.
They may thus be considered parasites that have gone astray but still
capable of existence in their abnormal environment. The possibility of
their developing to maturity after reencystment in a strange host if this
animal should be eaten by a pig has not been substantiated experimentally.
Seurat (1916) has counted 4,880 larve identified as P. sevalatus in a
single beetle, Scarabeus (Ateuchus) sacer. In addition there were 68
larve of Spirocerca sanguinolenta in the same beetle, making a total of
4,948 larve in the one insect.
Habronema musce (Carter, 1861) Diesing, 1861
This nematode in the adult stage occurs in the stomach of horses and
other equines, commonly in association with another closely related
species, H. microstoma. The life history of H. musc@ has been shown to
be as follows (Ransom, 1911, 1913; Hill, 1918; Bull, 1919): The eggs
or the larve pass out of the body of the host in the feces. They enter
the bodies of the larve of the common house fly, probably being swallowed,,
though the mode of entrance has not been determined by direct observa-
tion. The worm larve grow and develop in the developing flies and at
about the time the adult insects emerge from the pupal stage the larve
reach the infective stage. In this stage they are most commonly found
in the proboscis. The ingestion by horses of flies harboring the larve
brings the young parasites into the location where the adult occurs,
and presumably this is the common method by which the larve reach their
final host. The frequent swallowing of flies by horses is an undoubted
fact. The mouths of horses are very attractive to house flies especially
while the horses are eating, as any one can determine by a few minutes’
observation of the animals during the fly season. There is also another
possible and very probable way in which the larve are transferred to
horses, suggested of course by the habit of the larve of congregating
in the proboscis of the fly. We may expect that it will be demonstrated
66 SANITARY ENTOMOLOGY
in analogy with what has been shown to occur in Filaria transmission by
mosquitoes, that the larve of H. musce can actively leave the proboscis
of the fly while the insect is sucking moisture from the mouth or lips of
the horse. There is already indirect evidence that this does occur.
The researches of Descazeaux (1915), Bull (1916), and Van Saceghem
(1917) have shown that the nematodes which occur in cutaneous granulo-
mata and so-called summer sores of horses are morphologically similar
to the larve of Habronema musce and in all probability*belong to this
or a closely related species. Recently Van Saceghem (1918) from investi-
gations carried out in Africa has reached the conclusion that the
nematode of summer sores is Habronema musce and that it is introduced
by flies. Larvae from infested flies were placed in the eye of a horse kept
in an insect-proof enclosure, with the result that conjunctivitis and
verminous nodules of the nictitating membrane developed. In another
experiment two wounds were made on the skin of a horse, one protected
against flies and the other left uncovered. The horse was placed in a
stable in which 20 per cent of the flies were infested with Habronema.
The unprotected wound became transformed into a typical summer sore.
Bull (1919), who has made an extended study of cutaneous granulomata
of horses in Australia, believes that the larve of Habronema megastoma
are more often responsible for the production of habronemic granulomata
than either H. musce or H. microstoma.
Whether the Habronema larve in summer sores are able to migrate
ultimately to the stomach and complete their development to maturity
remains to be determined. Bull (1919) thinks it unlikely that the larve
of Habronema are able to reach the alimentary canal from the submucosa
of the external mucous membranes or from the subcutaneous tissues, and
Hill (1918) also notes that the evidence of the occurrence of such a
migration is quite insufficient.
It is of interest to note that Habronema musce was known as a
parasite of the fly long before its relation to the horse was demonstrated.
Carter in 1861 was the first to record the presence of the nematodes in
flies, following which they were frequently observed by entomologists and
others who had occasion to examine the proboscis of the fly under the
microscope.
Larval nematodes very similar to H. musc@ have been seen in the
proboscis of Stomoxys calcitrans by Johnston and others. The researches
of Hill (1918) and Bull (1919) have shown that as far as their experience
has gone the larve in this species of fly have invariably been Habronema
microstoma so that the occurrence of H. musce in S. calcitrans appears
questionable.
The fact that these more or less injurious parasites of the horse
depend upon flies for their existence is a point which may be added to
RELATION OF INSECTS TO THE PARASITIC WORMS 67
those commonly used in arguments for the necessity of fly eradication.
The possibility is also not excluded that flies may introduce Habronema
larve into human beings, in whose tissues they may perhaps Le able to live
for a time and do considerable damage. Though there is no evidence
that this ever occurs, the possibility is one that deserves consideration
from those who have opportunity to investigate the relation of flies to
wounds and other lesions of the skin and mucous membranes.
Habronema microstoma (Schneider, 1866) Ransom, 1911
Hill (1918) and Bull (1919) have shown that Habronema microstoma,
which, like H. musca, occurs in the adult stage in the stomach of the
horse and other equines, has a life history similar to that of H. musce.
Both of these writers have occasionally observed the presence of H.
microstoma in Musca domestica under experimental conditions but find
that the usual intermediate host is Stomoxys calcitrans. As they
repeatedly failed to infect §. calcitrans with the larve of H. musce@ it is
probable that the forms from S. calcitrans reported by Johnston (1912)
and others as H. musce were H. microstoma. Bull (1919) is of the
opinion that the larve of H. microstoma may sometimes be concerned in
the production of cutaneous granulomata of horses and that presumably
they are introduced into the skin by the proboscis of an infested fly.
Habronema megastoma (Rudolphi, 1819) Seurat, 1914
Habronema megastoma in its adult stage occurs in tumors in the
stomach of horses and other equines. Hill (1918) and Bull (1919) have
found that its life history is similar to that of H. musce, the house fly
(Musca domestica) acting as intermediate host in both cases. Attempts
to infect Stomowrys calcitrans with this species failed. Bull (1919) be-
lieves that the larve of H. megastoma introduced by infested flies are
the usual cause of habronemic granuloma of horses. So far as the normal
life history of H. megastoma is concérned he thinks that the presence of
the larve in the skin or mucous membranes of horses is to be considered
accidental and that it is unlikely that they can reach the alimentary tract
from such locations and become mature. According to his view, there-
fore, which is shared by Hill (1918), H. megastoma and also the other
species of Habronema reach the stomach of the horse as a result of the
animal’s swallowing infested flies.
Acuaria spiralis (Molin, 1858) Railliet, Henry and Sisoff, 1912
The adults of this nematode have been recorded as parasitic in the
esophagus and stomach of the domestic fowl. Insects have not been
68 SANITARY ENTOMOLOGY
shown to act as intermediate hosts, but insect-like animals commonly
known as sow-bugs apparently act as intermediate hosts, Piana (1897)
having found larval nematodes in an isopod (Porcellio levis) that corre-
sponded in morphology with immature nematodes found in chickens
harboring also the adult worms. Furthermore these larval nematodes
occurred in sow-bugs only in the locality where the chickens were found
to be infested. Although Piana identified the parasites that he found in
chickens as Dispharagus nasutus (Rudolphi), it is apparent from his
description and figures that they belonged to the species Acuaria spiralis
(Molin).
Filaria gallinarum Theiler, 1919
Theiler (1919) has recorded the occurrence of larval nematodes in a
species of termite (Hodotermes pretoriensis). Among the termites only
the workers were found to harbor these parasites, no infested soldiers
having been discovered. Infested termites can easily be distinguished
by the swollen abdomen which gives the insect a sort of balloon-like
appearance. According to Theiler, on many South African farms the
custom exists of digging up nests of termites and allowing the chickens
to feed on the insects, and the droppings of chickens running in the fields
are naturally scattered about and serve as food for the termites. Infested
termites were fed to young chickens that had been hatched in an incubator.
Adult worms that had evidently developed from the larve parasitic in
the termites were found in the intestine or stomach in 15 out of 1
chickens that had been thus fed, but none were found in control chickens.:
The proper generic position of this nematode described by Theiler as a
Filaria remains to be determined.
Ascaris lumbricoides Linneus, 1758
This common parasite of man has been definitely shown to have a
direct life history without intermediate host. The opinion of Linstow
(1886) that a species of Julus (guttulatus) acts as the intermediate host
is without foundation. The common house fly may swallow eggs of this
parasit2 as well as those of various other parasites which occur in the
feces of infested human beings. The eggs pass through the intestine of
the fly unhatched. Flies may thus scatter the eggs of Ascaris but there
is no evidence that mechanical carriage of the eggs in this way assists
materially in the spread of the parasite. There are various other natural
agencies more effective than insects in spreading infection with parasites
such as Ascaris. -Stiles, however (according to Nuttall, 1899), fed
females of Ascaris lumbricoides containing eggs to fly larve (Musca
domestica) and afterwards found the eggs in later stages of development
RELATION OF INSECTS TO THE PARASITIC WORMS 69
in the pupe and adult flies that developed from the larve. This sug-
gested the possibility that flies having become infested as larve might
convey the parasite to man by falling into or depositing their excreta
on food. Apparently these experiments have not been repeated.
-2. Parasitic Nematodes Whose First-stage Larvae Occur in the Blood or
Lymph of the Final Host and Leave the Body Through Ingestion
by Bloodsucking Insects
Filaria bancrofti Cobbold, 1877
This important parasite of man is widely distributed throughout the
world in tropical and subtropical countries. It occurs in the United
States, though apparently it is by no means common. Historically it is of
special interest because of the fact that it is the species which Manson
_ (1878) showed passed through certain metamorphoses in the bodies of
mosquitoes after the larve had been sucked up by these insects in the
blood of human beings affected with filariasis. Manson’s researches
coupled with confirmatory work by other investigators established the
novel fact of the transmission of an animal parasite by a bloodsucking
insect, and may be taken as the starting point in the development of our
knowledge concerning the part played by such insects in the spread of
disease-causing organisms. Lewis had also observed the passage of the
‘arve from the human host into mosquitoes. The first observation of
these larve in man was recorded by Demarquay in 1864 in Paris, the adult
female was discovered by Bancroft in 1876 in Queensland, and the adult
male by Bourne in 1888.
The adults of this species live in the lymphatic system, both vessels
and glands. The first-stage larve which are provided with a thin cutic-
ular sheath, apparently the transformed egg shell, are found in the blood
stream, usually periodically as first shown by Manson, that is, in consid-
erable numbers only at night or rather during the hours of sleep, as the
periodicity may be reversed by making the patient sleep during the day
time. One of the names of the parasite, Filaria nocturna, is based upon
the periodicity of the appearance of the larve in the blood. Various
pathological conditions have been attributed to Filaria bancrofti such as
adenitis, lymphangitis, abscesses, lymph scrotum, chyluria, and other
disturbances of the lymphatic system. The connection between filariasis
and elephantiasis is still a matter of argument among pathologists.
When taken into the stomach of a mosquito the larve lose their cutic-
ular sheaths. Within 24 hours they leave the alimentary tract, pass
into the body cavity, then into the muscles of the thorax. In the muscles
they become shortened to about half their original length and meanwhile
70 SANITARY ENTOMOLOGY
increase to twice or more than twice their original thickness, developing
into what is known as the sausage stage of general occurrence in the
development of Filaria larve. Developing beyond this stage they increase
rapidly in length, cast their skins at least once, and in one to two weeks
after infection of the mosquito, or longer, according to temperature and
the species of mosquito infected, they complete their larval development
so far as the intermediate host is concerned, reaching a length finally
about three to five times the length of the first-stage larve and a thickness
about three or four times the original thickness. They leave the muscles,
enter the body cavity, and migrate into various locations, posterior por-
tions of the body, legs, palpi, but in greatest numbers into the labium.
From the evidence afforded by the experiments of Noé (1900) with
Dirofilaria immitis and additional experiments by Bancroft (1901),
Lebredo (1904-1905), Fiilleborn (1908), and others, it has been con-
cluded by analogy in the case of Filaria bancroftt that when an infected
mosquito bites a human being the filaria larve bore through a thin portion
of the labium known as Dutton’s membrane, and more rarely other thin
portions of the proboscis, actively penetrate the skin of the individual
attacked, and reach the lymphatic system where they complete their
development to maturity.
Both anopheline and culicine mosquitoes can serve as intermediate
hosts of Filaria bancrofti including the following species (see also
Chapter XVII):
Anopheline mosquitoes
Anopheles (Myzomyia) rossi Giles.
& (Pyretophorus ) costalis Loew.
i (Myzorhynchus) sinensis Wiedemann.
s ss “ pediteniatus Leicester,
er = barbirostris Van der Wulp.
Culicine mosquitoes
Culex pipiens Linnaeus Aedes argenteus Poirret (Stego-
myta calopus Meigen)
“ quinquefasciatus Say (fati- Aedes gracilis Leicester (Stego-
gans Wiedemann) myia)
Aedes scutellaris Walker (Culex
“ — gelidus Theobald albopictus Skuse)
“ sttiens Wiedemann Mansonioides uniformis Theobald
Mansonioides annulipes Theobald
Scutomyia albolineata Theobald
Taeniorhynchus domesticus Lei-
" cester
RELATION OF INSECTS TO THE PARASITIC WORMS 71
Besides those named about a dozen other species of mosquitoes have
been tested as hosts of Filaria bancrofti with negative results, or with
results showing that the parasites would only develop imperfectly. Fleas,
lice, and Stomoxys have been tested with negative results.
Prophylaxis against Filaria bancrofti evidently consists in measures
similar to those employed in malaria eradication with reference to mos-
quito control.
Filaria (Loa) loa (Cobbold, 1864)
This parasite of man is a West African species. It has been brought
to America in the slave trade but never established in the New World.
The adults live usually in the subcutaneous connective tissue but have
been found elsewhere in relation with the serous membranes of the ab-
dominal and thoracic viscera. They move about from place to place
and can change their location rather rapidly; for example, one of these
worms has been seen to cross the bridge of the nose beneath the skin
within a period of an hour or two. In their progress beneath the skin
in various parts of the body they give rise to transient edematous areas
known as Calabar swellings. The larvae produced by the females enter
the blood stream where they are found in the peripheral vessels during
the day time, contrary to the habits of the larvae of Filaria bancrofti.
Because of this characteristic periodicity of the larvae, Filaria loa has
been also named F’. diuwrna. The larvae of F. loa are provided with a
sheath relatively much longer than that of the larvae of F. bancrofti.
Experiments with various anopheline and culicine mosquitoes, and
Glossina palpalis have given negative results as to the possibility of these
insects acting as intermediate hosts. From Leiper’s (1913) researches,
it would appear that a species of Chrysops (probably C. dimidiata or
C. longicornis) acts as the intermediate host of Filaria loa, the larve
undergoing their development in the salivary glands of the insect. Ac-
cording to Ringenbach and Guyomarc’h (1914), the intermediate host in
the Congo is Chrysops centurionis. Kleine (1915) in West Africa found
82 out of 600 Chrysops examined. to be infested with larval nematodes
which he took to be the larvae of F’. Joa though he does not give sufficient
evidence to support his claims.
Filaria demarquayi Manson, 1895
This parasite, generally considered identical with Filaria juncea and
F. ozzardi, occurs in man in the West Indies and in British Guiana. The
adult has been found in the mesentery and under the peritoneum of the
abdominal wall. The first-stage larvae occur in the blood stream. Their
appearance in the circulation is not periodic. According to Low (1902)
72 SANITARY ENTOMOLOGY
the larvae can be developed to the so-called “sausage” stage in Aedes
argenteus (Stegomyia calopus). Experiments with Anopheles albimanus
(albipes), Culex taeniatus, C. quinquefasciatus (fatigans), and other
mosquitoes, fleas, and ticks failed to result in any development of the
larvae. Fiilleborn (1908) was able to develop the larvae to the sausage
stage in Anopheles maculipennis and Aedes argenteus (Stegomyia calo-
pus), but no development occurred in the tick, Ornithodoros moubata.
Further investigations are necessary to determine what insects serve as
intermediate hosts for F. demarquayi.
Filaria philippinensis Ashburn and Craig, 1906
The adult stage of this parasite of man is unknown. The first-stage
larvae occurring in the blood of man are morphologically identical with
those of Filaria bancrofti. Unlike the latter, however, they show no
periodicity. Ashburn and Craig (1907) have shown that the larvae will
undergo development in mosquitoes, Culex quinquefasciatus (fatigans).
similar to that of the larvae of F. bancrofti. It is questionable whether
F. philippinensis should be recognized as a distinct species.
Filaria tucumana Biglieri and Ardoz, 1917
This species, the adults of which are unknown, is based on microfilarie
found frequently in the blood of human beings in Argentina. It appears
to be comparatively harmless. Biglieri and Ardoz (1917) conclude that
mosquitoes act as intermediate hosts and apparently consider Aedes
argenteus (Stegomyia calopus) the most important vector, though defi-
nite proof of this has not been, obtained.
Filaria cypselie Annett, Dutton and Elliott, 1901
The adult stage of Filaria: cypseli occurs in the subcutaneous tissue
of the head of the swift, Cypselus affinis, also beneath the subcranial
fascia. The embryos or first-stage larvae occur in the lymph and rarely
in the peripheral blood of infested birds. Dutton (1905) has described
various larval stages of the parasite which he finds in an undetermined’
species of bird-louse belonging to the subfamily Leiothinae that occurs
on swifts. The first-stage larva as it is found in the blood of the bird
and the stomach of the louse is provided with a sheath as in various
other species of Filaria. This sheath is lost and the larva probably soon
penetrates the stomach wall. The next stage of the parasite is found
in the fat-body of the louse as are two later stages described by Dutton.
The last stage of development seen by him is found free in the body
RELATION OF INSECTS TO THE PARASITIC WORMS 3
cavity and this is probably the stage in which the parasite is trans-
ferred to the bird; whether as a result of ingestion of the louse by the
swift, or as a result of the active migration of the worm from the
louse while the insect is engaged in biting, has not been determined.
Filaria martis Gmelin, 1790
Filaria martis (or Filaria quadrispina) according to various writers
occurs in its adult stage beneath the skin and in the abdominal and
thoracic cavities of Mustela foina. Baldasseroni (1909) has found filaria
embryos in the intestine of ticks (Ivodes ricinus) taken from a marten
harboring the adult nematode, and he suggests that ticks may act as
intermediate hosts. As in the case of Acanthocheilonema grasst, further
evidence is necessary before ticks can be considered to play a part in the
life history of Filaria martis.
Dirofilaria immitis (Leidy, 1856) Railliet and Henry, 1911
This nematode, sometimes erroneously listed as a parasite of man,
lives in the right side of the heart and pulmonary artery of the dog.
The larvae are found in the circulation, most numerous at night as in
the case of Filaria bancroftt, As would be expected from the location
of the adult parasite it may give rise to serious symptoms, and affected
dogs commonly succumb to the disturbances which it causes. It is a
troublesome parasite among hunting dogs in the Southern United States.
Noé (1900) showed that the larvae of this nematode continue their de-
velopment in certain species of mosquitoes when sucked up with the
blood of infested dogs. In 24 to 36 hours after reaching the stomach
of the mosquito the larvae pass into the Malpighian tubules. They
undergo a certain growth and development in this location, and 11 or 12
days after reaching the mosquito they break out of the tubules, enter
the body cavity, and migrate to the labium. From the labium of the
mosquito they reach their final host, the dog, in the same manner as
F. bancrofti reaches its human host, namely, by breaking through thin
portions of the cuticle of the labium at the time the mosquito is engaged
in biting its victim and then penetrate the skin, finally migrating to the
heart. Mosquitoes infested with the larve of D. immitis are commonly
killed by the parasites owing to their destructive action on the Malpighian
tubules, Noé having observed that only about half the mosquitoes that
become infested survive. In Italy the common intermediate hosts appear
to be Anopheles maculipennis, A. bifurcatus, A. (Myzorhynchus) sinensis
pseudopictus, and A. (Myzomyia) superpictus among anophelines ; culi-
cines, according to Noé such as Culex penicillaris, C. malariae, and ex-
ceptionally C. pipiens, can also act as intermediate hosts.
74 SANITARY ENTOMOLOGY
Dirofilaria repens, Railliet and Henry, 1911
In the adult stage this nematode, which is a very similar parasite to
D. immitis, occurs in the subcutaneous connective tissue of the dog. Its
larvae enter the blood stream whence they are liable to be ingested by
blood-sucking insects. According to Bernard and Bauche (1913) the
yellow fever mosquito Aedes argenteus (Stegomyia calopus) acts as the
intermediate host. These investigators while admitting that other species
of mosquitoes might act as intermediate hosts of D. repens, found that
A. argenteus best fulfilled the natural conditions for the transmission
of the parasite, and their experiments were carried out with this species
of mosquito. They followed the various stages in the development of
the larval nematodes in mosquitoes fed experimentally upon infested dogs.
About 2 days after the mosquito has been fed the nematode larvae leave
the lumen of the alimentary tract and penetrate into the Malpighian
tubules where they undergo most of their growth and development. By
the eighth day the larvae may be found in some cases to have migrated
into the body cavity and thoracic muscles and the last stage of develop-
ment in mosquitoes may be found in the proboscis as early as the ninth
day. Six young dogs (10 days old) were submitted to the bites of
A. argenteus (fed 10 to 15 days previously on infected dogs) every morn-
ing for fifteen days. Six young dogs of the same age were kept as con-
trols, not exposed to mosquito bites. The bitten dogs all died within
thirty days. Ecchymotic spots were found beneath the skin at the points
of the mosquito bites, but no filarias were discovered. The other dogs all
survived the experiment. Under natural conditions the youngest dogs
found infested with D. repens by Bernard and Bauche were at least a
year old, hence the writers conclude that the development of the parasite
is very slow. Although they did not succeed in completing their experi-
ments by recovering the adult stage of the parasite in dogs, following
bites by infected mosquitoes, it appears safe to conclude that D. repens
is transmitted by mosquitoes in a manner similar to that in which D.
immitis is transmitted.
Acanthocheilonema perstans (Manson, 1891) Railliet, Henry and
Langeron, 1912
This parasite occurs in man in tropical Africa and British Guiana,
the adults in the intraperitoneal connective tissue and fatty tissue of the
abdominal viscera and pericardium, and the first-stage larvae in the
blood stream. The larvae exhibit no periodicity in their appearance in
the circulation, the name perstans having reference to this fact.
Christy (1903) has suggested that Ornithodoros moubata may act as
RELATION OF INSECTS TO THE PARASITIC WORMS 5
the intermediate host of Acanthocheilonema perstans. Wellman (1907)
has reported that the larvae of this parasite are taken up by Ornithodoros
moubata and according to his statements develop very slowly in this
tick, advanced stages not being found until more than two months after
infection of the tick. The suggestion made by Feldmann (1905), influ-
enced by Bastian (1904), that the larvae of A. perstans may pass out
of the body of the tick with its eggs into bananas and afterwards being
swallowed with this fruit by human beings is a mode of infection which
requires no consideration as a possibility without more supporting evi-
dence than has yet been advanced.
Hodges (1902) observed Filaria larvae in the thoracic muscles of
the mosquitoes, Panoplites sp. and Aedes argenteus (Stegomyia calopus),
three days after they had been fed on perstans blood. Low (1903) was
able in one case to obtain development of perstans larvae to the sausage
stage in a mosquito (Chrysoconops fuscopennatus). Fiilleborn (1908,
1913) obtained a similar development in Anopheles maculipennis. Fiille-
born and Low obtained negative results with various species of mosquitoes,
sand fleas, lice and simuliids.
Acanthocheilonema grassii (Noé, 1907) Railliet, Henry and
Langeron, 1912
The adults of this nematode occur in the subcutaneous and intermus-
cular connective tissue and peritoneal cavity of the dog. The larvae
produced by the females are unusually large, about twice as long and
thick as the average filaria larva, and according to Noé (1907, 1908)
do not pass into the blood stream as is generally the case among the
filarias. Noé assumed that the larve are restricted to the lymphatic
system, and accordingly concluded that the intermediate host would most
likely be a tick or similar slow feeding ectoparasite. In fact he found
nematode larvae corresponding to those of A. grassii in Rhipicephalus
sanguimeus, a tick of common occurrence in regions where the dogs are
infested with the nematode in question. Furthermore he states that all
of the ticks attached to dogs infested with the nematode become infested
with the larval worms. Additional evidence that R. sanguineus acts as
the intermediate host is that the larvae in the ticks undergo growth and
development, at least one molting period having been observed between
successive stages. As R. sanguineus is a tick which falls to the ground to
transform from the nymphal to the adult stage, the necessary opportunity
is afforded for the transmission of A. grassii from one dog to another.
Noé remarks that the nymph of this tick ingests large quantities of
lymph. The larval nematodes taken in with the ingested lymph penetrate
the intestinal wall into the body cavity where they undergo the develop-
76 SANITARY ENTOMOLOGY
ment necessary before they are ready to be returned to the definitive host,
after transformation of the nymphal tick to the adult stage. Noé be-
lieves that the dog becomes infected during the initial phase of attach-
ment of the adult. He also suggests that adult males which, unlike adult
females, may pass from one host to another are capable of acquiring
infection from one dog and transferring it to another. He has found
as many as 22 larvae of A. grassii in one male tick. Noé is of the
opinion that the larvae escape through thin portions of the cuticle of
the mouth parts of the tick and thus reach the final host in a way similar
to that followed by the larvae of D. immitis and other filarias trans-
mitted by mosquitoes.
It is of interest to note that Grassi and (dishariacis (1890) found
larval nematodes in Rhipicephalus siculus (—=R. sanguineus) which they
identified as the larve of Filaria recondita (—=Acanthocheilonema recon-
ditum). Noé thinks that these larvae may have been A. grassii rather
than A. reconditum.
Evidently further investigations into the life history of A. grassii are
necessary before ticks can be accepted as the intermediate host of this
parasite.
Acanthocheilonema reconditum (Grassi, 1890) Railliet, Henry and
Langeron, 1912
This nematode is a parasite of the dog and in the adult stage has been
collected from adipose tissue in the neighborhood of the kidney. Accord-
ing to Grassi and Calandruccio (1890) the first-stage larvae occur in the ©
blood stream, and are the so-called Haematozoa of Lewis which have
been seen by many observers, first by Gruby and Delafond (1843), after-
wards by Lewis and others. Apparently, however, the larvae seen in
the blood of dogs by Grassi and Calandruccio as well as those known
as Lewis’s Haematozoa are in reality the larvae of Dirofilaria repens.
Grassi and Calandruccio describe various stages of nematode larvae
found in fleas (Ctenocephalus canis, C. felis, and Pulex irritans) and in a
tick (Rhipicephalus siculus=R. sanguineus) as developmental stages in
the life history of A. reconditum. According to Noé (1907, 1908), the
larvae found in R. sanguineus by Grassi and Calandruccio were probably
those of Acanthocheilonema grassii.
Owing to the confusion existing with reference to the identity of the
parasite that Grassi and Calandruccio studied, the species to which the
larval nematodes observed in fleas belong, is uncertain. Grassi and Calan-
druccio’s experiments can not be considered conclusive so far as con-
cerns the life history of A. reconditum.
RELATION OF INSECTS TO THE PARASITIC WORMS "7
Setaria labiato-papillosa (Alessandrini, 1838) Railliet and Henry, 1911
The adults of this nematode are common parasites in the peritoneal
cavity of cattle in various parts of the world including the United States.
The larvae enter the blood stream, and Nod (1903) identifies certain
larval nematodes found in Stomorys calcitrans as belonging to this
species. That this fly actually serves as the intermediate host, however,
remains to be proved.
The possibility is not excluded that Nod mistook Habronema larve
for the larve of §. labiato-papillosa.
Oncocerca
About twelve species of this genius have been described. Onco-
cerca voloulus in the adult stage occurs in nodular tumors beneath the
skin of man in Africa. Oncocerca caecutiens is found in subcutaneous
nodules on the head among natives living at a certain altitude on the
west coast of Guatemala and is the cause of so-called “Coast erysipelas.”
O. gibsoni causes worm nodules in the brisket and other locations in
cattle in Australia. T'wo species occur in cattle in the United States:
one undetermined species is found in relation with the ligaments of the
legs and neck, the other (0. lienalis) is found in the gastrosplenic liga-
ment. Oncocerca larvae have not been found in the blood stream but
may be recovered from the lymph spaces in the neighborhood of the adult
worms. The intermediate hosts of these nematodes are unknown but biting
insects have been suspected. The results of experiments have been nega-
tive. Brumpt (1903) has suggested the possibility that Glossina palpalis
acts as intermediate host of O. volvulus.
Robles (1919) suggests that two species of Simulium (close to S.
dimelli and S. samboni) may be involved as vectors of O. caecutiens in
view of the fact that these flies are most numerous in the places where
the largest number of cases of Oncocerca occur. Furthermore these
species of flies are absent in lower altitudes corresponding with the absence
of Oncocerca. .
3. Other Nematodes
Different investigators have recorded the occurrence of larval nema-
todes of unknown species in various insects. Usually these have been
very poorly described and it is questionable in many cases whether
if found again they could be recognized as the same forms. Some of
them may be the larval forms of nematodes whose adults are already
known as parasites of higher animals. Among such larvae of uncertain
_ identity may be mentioned Filaria geotrupis in the abdominal cavity
.
78 SANITARY ENTOMOLOGY
of Geotrupes stercorarius (possibly the larva of Physocephalus sexala-
tus), Filaria ephemeridarum in the abdominal cavity of the larvae of
Ephemera vulgata and Oligoneuria rhenana, Filara rytipleuritis (of
Magalhaes, 1900, not Deslongchamps, 1824) in the abdominal cavity of
Periplaneta americana (possibly a Gongylonema according to Seurat),
Filaria stomoxeos in Stomoaxys calcitrans (possibly the larva of Hab-
ronema microstoma), Mastophorus echiurus, and Cephalacanthus mona-
canthus in Tenebrio molitor (probably larvae of Protospirura muris),
Mastophorus globocaudatus and Cephalacanthus triacanthus in
Geotrupes stercorarius (possibly larvae of Physocephalus sexalatus).
4. Mermithidae
These worms which resemble the nematodes and are usually grouped
with them are not known to be of importance in medical zoology. One
species, of uncertain identity, is of interest, however, as it is the so-called
“cabbage snake” whose presence among the leaves of cabbage has alarmed
people who have encountered it. This worm, like others of the same
family, undoubtedly passes through a portion of its development in the
body of an insect, probably one of the common caterpillars that attack
cabbage. Similar worms have been found in apples.
GORDIACEA OR HORSE-HAIR WORMS
The Gordiacea or horse-hair worms (as which they are popularly
known from the superstitious belief that they are animated horse hairs)
are of medical interest because several species have been recorded as
parasites of man. They gain entrance to the alimentary tract by being
swallowed in drinking water. The adults are of not uncommon occur- |
rence in springs and other surface waters. When swallowed by human
beings they are usually soon vomited up but they have in some cases
apparently survived in the intestine for several months before they were
finally expelled. In some species, and probably in all, insects serve as
hosts for the larval stages. The adults deposit their eggs in the water
in which they live. The larvae hatching from the eggs enter the bodies
of insects such as grasshoppers (as for example, in the case of Gordius
robustus) or crickets (as for example, in the case of Paragordius varius )
or in the case of other species they may enter aquatic insect larvae,
which may later be devoured by carnivorous water insects. In the latter
the worms undergo their development until they have reached or ap-
proached maturity when they burst out of the infested insect and escape
into the water. The following species of Gordiacea have been recorded
as accidental parasites of man: Gordius aquaticus, G. chilensis, Para-
RELATION OF INSECTS TO THE PARASITIC WORMS ‘9
gordius varius (a common American species), Paragordius tricuspidatus,
Parachordodes tolusanus, Parachordodes violaceus, Parachordodes pus-
tulosus, and Chordodes alpestris.
ACANTHOCEPHALA OR THORN-HEADED WORMS
This highly specialized group of parasites, commonly classified in the
Nemathelminthes, with which it has little in common beyond a superficial
resemblance in the general shape of the body, has been but little studied.
Most of the known species are parasitic in birds.
Macracanthorhynchus hirudinaceus (Pallas, 1781) Travassos, 1916
This worm in the adult stage (sometimes called the giant thorn-
headed worm) is a common parasite of the intestine of the pig and is said
to occur as a parasite of man along the River Volga. Its eggs pass out
of the body of the host in the feces. Swallowed by certain insects [larvae
of Melolontha melolontha, Cetonia aurata, Phyllophaga arcuata (Lach-
nosterna), and Diloboderus abderus] the eggs hatch, and the larvae
develop into an intermediate stage, which in turn completes its develop-
ment to maturity when the infested grub is eaten by a pig.
Moniliformis moniliformis (Bremser, 1819) Tyravassos, 1915
This parasite in its adult stage (sometimes called the beaded thorn-
headed worm) is of common occurrence in the intestine of rats and other
rodents in tropical and subtropical regions, and has been found in man
in Italy. The life cycle is similar to that of the giant thorn-headed worm
except for the difference in hosts. According to Grassi and Calandruccio
(1888), Blaps mucronata acts as an intermediate host. According to
Magalhaes (1898) and Seurat (1912), the usual intermediate host is a
cockroach (Periplaneta americana).
COMPENDIUM OF PARASITES ARRANGED ACCORDING TO INSECT HOSTS 2
Aphaniptera (Siphonaptera)—fleas
Ceratophyllus fasciatus Bosc :
Hymenolepis diminuta
? Hymenolepis nana
Ctenocephalus canis Curtis
? Acanthocheilonema reconditum
2 The scientific names of the insects have been revised by the editor.
80
SANITARY ENTOMOLOGY
Dipylidium caninum
Hymenolepis diminuta
Ctenocephalus felis Bouché
? Acanthocheilonema reconditum’
? Dipylidium caninum
Pulex irritans Linnaeus
? Acanthocheilonema reconditum
Dipylidium caninum
Hymenolepis dimimuta
Xenopsylla cheopis Rothschild
Hymenolepis diminuta
? Hymenolepis nana
? Protospirura muris
Diptera—fiies
Aedes argenteus Poirret (Stegomyia calopus Meigen)
Acanthocheilonema perstans (incomplete development)
Dirofilaria repens
Filaria bancrofti
Filaria demarquayi (incomplete development)
? Filaria tucumana
Aedes gracilis Leicester (Stegomyia)
Filaria bancrofti
Aedes scutellaris Walker (Culex albopictus Skuse)
Filaria bancrofti
Anopheles barbirostris Van der Wulp (Myzorhynchus)
Filaria bancrofti
Anopheles bifurcatus Linnaeus
Dirofilaria immitis
Anopheles costalis Loew (Pyretophorus)
Filaria bancrofti
Anopheles maculipennis Meigen (claviger Fabricius)
Acanthocheilonema perstans (incomplete development)
Dirofilaria immitis
Filaria demarquayi (incomplete development)
Trematode
RELATION OF INSECTS TO THE PARASITIC WORMS
Anopheles rossi Giles (Myzomyia)
Trematode
Filaria bancrofti
Anopheles sinensis Wiedemann (Myzorhynchus)
Filaria bancrofti
Anopheles sinensis peditaeniatus Leicester (Myzorhynchus)
Filaria bancrofti
Anopheles sinensis pseudopictus Grassi (Myzorhynchus)
Dirofilaria immitis
Anopheles superpictus Grassi (Myzomyia)
Dirofilaria immitis
Chironomus plumosus Linnaeus
Lecithodendrium ascidia
Chrysoconops fuscopennatus (Theobald) (‘Taeniorhynchus)
Acanthocheilonema perstans (incomplete development)
Chrysops spp.
Filaria (Loa) loa
? Chrysops centurionis Austen
Filaria (Loa) loa
? Chrysops dimidiata Van der Wulp
Filaria (Loa) loa
? Chrysops longicornis Macquart
Filaria (Loa) loa
Culex gelidus Theobald
Filaria bancrofti
a
Culex malariae Grassi
Dirofilaria immitis
Culex penicillaris Rondani
Dirofilaria immitis
81
SANITARY ENTOMOLOGY
Culex pipiens Linnaeus
Dirofilaria immitis
Filaria bancrofti
Culex quinquefasciatus Say (skusei Giles) (fatigans Wiedemann)
Filaria bancrofti
Culex sitiens Wiedemann
Filaria bancrofti
Mansonioides annulipes Theobald
Filaria bancrofti
Mansonioides uniformis Theobald
Filaria bancrofti
Musca domestica Linnaeus
Choanotaenia infundibulum
Habronema muscae
Habronema microstoma
Habronema megastoma
? Davainea cesticillus
? Davainea tetragona
Panoplites sp.
Acanthocheilonema perstans (incomplete development)
Scutomyia albolineata Theobald
Filaria bancrofti
Stomoxys calcitrans Linnaeus
Filaria stomoxeos
Habronema microstoma
? Habronema muscae
? Setaria labiato-papillosa
? Hymenolepis carioca
Taeniorhynchus domesticus Leicester
Filaria bancrofti
Neuroptera
Sialis lutaria (Linnaeus)
Trematode
RELATION OF INSECTS TO THE PARASITIC WORMS
Trichoptera—hairy-winged insects
Anabolia nervosa (Leach) Curtis
Allocreadium isoporum
Opisthioglyphe rastellus
Chaetopteryx villosa (Fabricius)
Allocreadium isoporum
Drusus trifidus McLachlan
Trematode
Limnophilus flavicornis (Fabricius)
Opisthioglyphe rastellus
Limnophilus griseus (Linnaeus)
Opisthioglyphe rastellus
Limnophilus lunatus (Curtis)
Opisthioglyphe rastellus
Limnophilus rhombicus (Linnaeus)
Opisthioglyphe rastellus
Mystacides nigra (Linnaeus)
Trematode
Notidobia ciliaris (Linnaeus)
Trematode
Phryganea grandis
Trematode
Phryganea sp.
Lecithodendrium chilostomum
Rhyacophila nubila Zetterstedt
Trematode
Lepidoptera—toths, butterflies
Asopia farinalis (Linnaeus)
Hymenolepis dimimuta
Nymphula nymphaeata (Linnaeus) (Hydrocampa)
Trematode
83
84
SANITARY ENTOMOLOGY
Coleoptera—beetles
Akis goryi (Solier)
Spirocerca sanguinolenta
Spirura gastrophila
Akis spinosa (Linnaeus)
Hymenolepis diminuta
Aphodius rufus (Moll) var. castaneus Marsh
Arduenna strongylina
Aphodius coloradensis Horn
Gongylonema scutatum
Aphodius femoralis Say
Gongylonema scutatum
Aphodius fimetarius Linnaeus
Gongylonema scutatum
Aphodius granarius Linnaeus
‘Gongylonema scutatwm
Aphodius vittatus Say
Gongylonema scutatum
Blaps appendiculata
Gongylonema sp. (G. scutatwm according to Seurat)
Blaps sp.
Gongylonema brevispiculum
Blaps sp. (near appendiculata )
Spirura gastrophila
Gongylonema sp. (G. scutatum according to Seurat)
Blaps emondi
Gongylonema sp. (G. scutatum according to Seurat)
Blaps mucronata Latreille
Moniliformis moniliformis
Blaps strauchi Reiche
Spirura gastrophila
Gongylonema sp. (G. scutatum according to Seurat)
RELATION OF INSECTS TO THE PARASITIC WORMS
Cetonia aurata (Linnaeus)
Macracanthorhynchus hirudinaceus
Copris hispanus (Linnaeus)
Spirocerca sanguinolenta
Diloboderus abderus Sturm
Macracanthorhynchus hirudinaceus
Geotrupes douei Gory
? Gongylonema mucronatum
Spirocerca sanguinolenta
Physocephalus sexalatus
Geotrupes stercorarius (Linnaeus)
Cephalacanthus triacanthus
Filaria geotrupis
Mastophorus globocaudatus
? Physocephalus sexalatus
Gymnopleurus mopsus (Pallas)
? Gongylonema mucronatum
Gymnopleurus sturmi Mac Leay
? Gongylonema mucronatum
Spirocerca sanguimolenta
Ilybius fuliginosus (Fabricius)
Haplometra cylindracea
Melolontha melolontha Linneus (vulgaris Fabricius)
Macracanthorhynchus hirudinaceus
Chironitis irroratus Rossi (Onitis)
? Gongylonema mucronatum
Onthophagus spp.
Arduenna strongylina
Spirura gastrophila
Onthophagus bedeli Neitt.
? Gongylonema mucronatum
Physocephalus sexalatus
85
86
SANITARY ENTOMOLOGY
Onthophagus hecate Panzer
Gongylonema scutatum
Onthophagus nebulosus Reiche
Physocephalus sexalatus
Onthophagus pennsylvanicus Harold
Gongylonema scutatum
Phyllophaga arcuata Smith (Lachnosterna)
Macracanthorhynchus hirudinaceus
Scarabaeus (Ateuchus) sacer Linnaeus
? Gongylonema mucronatum
Physocephalus sexalatus
Spirocerca sanguinolenta
Scarabacus (Ateuchetus) variolosus Fabricius
Physocephalus sexalatus
? Spirocerca sanguinolenta
Scaurus striatus Fabricius
Hymenolepis diminuta
Tenebrio molitor Linnaeus
Cephalacanthus monacanthus
Gongylonema neoplasticum
Hymenolepis diminuta
? Hymenolepis microstoma
Mastophorus echiurus
Protospirura muris
Water beetles
Pleurogenes claviger
Pleurogenes medians
Prosotocus confusus
Mallophaga—bird lice
Leiothinae (? genus ? species)
Filaria cypseli
Trichodectes latus Nitzsch (canis DeGeer)
Dipylidium caninum
RELATION OF INSECTS TO THE PARASITIC WORMS
Isoptera—termites
Hodotermes pretoriensis Fuller
Filaria aallinarum
Odonata—dragonflies
Aeschna sp.
Prosotocus confusus
Agrion sp.
Gorgodera pagenstecheri
Gorgodera varsoviensis
Pleurogenes medians
Calopteryx virgo (Linnaeus)
Halipegus ovocaudatus
Pnewmonoeces similis
Cordulia sp.
Prosotocus confusus
Epitheca spp.
Gorgodera cygnoides
Gorgodera pagenstecheri
Gorgodera varsoviensis
Plectoptera—mayfiies
Cleon dipterum (Linnaeus) Stephens
? Opisthioglyphe rastellus
Ephemera vulgata Linnaeus
Allocreadium isoporum
Filaria ephemeridarum
? Opisthioglyphe rastellus
Ephemeridae
Lecithodendrium ascidia
Oligoneuria rhenana Imhoff
Filaria ephemeridarum
87
88
SANITARY ENTOMOLOGY
Plecoptera—stoneflies
Perlidae
Lecithodendriwm ascidia
Trematode
Orthoptera—cockroaches, etc.
Blattella germanica (Linnaeus) Caudell
Gongylonema neoplasticum
Gongylonema scutatum (experimental infection)
Periplaneta americana (Linnaeus) Burmeister
Filaria rytipleuritis of Magalhies, 1900
Gongylonema neoplasticum
Moniliformis moniliformis
Blatta orientalis Linnaeus
Gongylonema neoplasticum
? Spirocerca sanguinolenta
Spirura gastrophila
Dermaptera—earwigs
Anisolabis annulipes Lucas
Hymenolepis diminuta
Myriapoda—nmillipedes, centipedes ?
Fontaria virginiensis (Drury)
Hymenolepis diminuta
Glomeris limbata
Tapeworm larvae
Julus sp.
Hymenolepis diminuta
Julus guttulatus
Nematode larva
Acarina—ticks, mites ®
Ixodes ricinus (Linnaeus) Latreille
? Filaria martis
3 Included in list because of their similarity to insects.
RELATION OF INSECTS TO THE PARASITIC WORMS 89
Ornithodoros moubata (Murray)
‘'? Acanthocheilonema perstans
Rhipicephalus sanguineus (Latreille)
? Acanthocheilonema grassii
? Acanthocheilonema reconditwm
Isopoda—sowbugs *
Porcellio laevis Latreille
? Acuaria spiralis
LIST OF REFERENCES
Ackert, James E.
1918.—On the life cycle of the fowl cestode, Davainea cesticillus
(Molin). (Preliminary communication.) Jour. Parasit. Ur-
bana, IIl., Vol. 5, No. 1, Sept., pp. 41-43, pl. 5, figs. 1-4.
1919.—On the life history of Davainea tetragona (Molin), a fowl
tapeworm. Jour. Parasit., Urbana, IIl., Vol. 6, No. 1, Sept.,
pp. 28-34.
Ashburn, P. M., and Craig, Charles F.
1907.—Observations upon Filaria philippimensis and its development
in the mosquito. Philippine Journ. Sci., vol. 2B, No. 1, Mar.,
pp. 1-14, pls. 1-7, figs. 1-26.
Baldasseroni, Vincenzo.
1909.— ‘Ixodes ricinus” L. infetto da embrioni di Filaria. Bull. Soc.
Entom. Ital., vol. 40, Nos. 3-4; pp. 171-174, Dec. 30.
Bancroft, Thomas L.
1901.—Preliminary notes on the intermediate host of Filaria immitis
Leidy. Journ. Trop. Med. Lond., vol. 4, Oct. 15, pp. 347-349.
Bastian, H. Charlton.
1904.—Note on the probable mode of infection of the so-called Filaria
perstans, and on the probability that this organism really
belongs to the genus Tylenchus (Bastian). Lancet, vol. 166,
No. 4196, vol. 1, No. 5, Jan. 30, pp. 286-287, figs. 1-3,
Bernard, P. Noél, and Bauche, J
1913.—Conditions de propagation de la filariose sous-cutanée du chien.
Stegomyia fasciata hédte intermediaire de Dirofilaria repens.
Bull. Soc. Path. Exot., vol. 6, No. 1, Jan. 8, pp. 89-99, sie 1-9.
*Included in list because of their similarity to insects.
90 SANITARY ENTOMOLOGY
Biglieri, R., and Ardoz, J. M.
1917.—Contribucién al estudio de una nueva filariosis humana encon-
trada en la Reptblica Argentina (Tucumdn ), ocasionada por la
“Filaria tucumana.” 1. Confer. Soc. sud-am. de hig. [etc.],
Buenos Aires Sept. 17-24, 1916, pp. 403-422.
Brumpt, Emile.
1903.—Sur réle des mouches tsé-tsé en pathologie exotique. Compt.
Rend. Soe. Biol., vol. 55, No. 34, Dec. 4, pp. 1496-1498.
Bull, Lionel B.
1916.—A granulomatous affection of the horse—Habronemic granu-
lomata (cutaneous habronemiasis of Railliet). Journ. Comp.
Path. and Therap., vol. 29, No. 3, Sept. 30, pp. 187-199, figs.
1-5.
1919.—A contribution to the study of habronemiasis: A clinical,
pathological, and experimental investigation of a granulomat-
ous condition of the horse-habronemic granuloma. pp. 85-141,
pls. 13-15, figs. 1-8. [Reprint from Tr. Roy. Soc. South
Australia, v. 43.]
Christy, Cuthbert.
1903.—The distribution of sleeping sickness, Filaria perstans, etc.,
in East Equatorial Africa. (Preliminary report dated Oct.
31, 1902). Roy. Soc. Rep. Sleep.-Sick. Comm., No. 2, Nov.,
pp. 3-8, 3 maps.
De Magalhies, Pedro Severiano,
1898.—Notes d’helminthologie brésilienne. [5. note] Arch, Parasitol.,
vol. 1, No. 3, July, pp. 361-368, figs. 1-4.
1900.—Notes d’helminthologie brésilienne. [8. note] Arch. Parasitol.
vol. 8, No. 1, May 15, pp. 34-69, figs. 1-25.
Descazeaux, J. ,
1915.—Contribution 4 l’étude de Il’ “esponja” ou plaies d’été des
équidés du Brésil. (Rapport de Railliet, 17 juin). Bull. Soc.
Centr. de Méd. Vét., vol. 69, Jan. 30-Sept. 30, pp. 468-486, figs.
1-3.
Deslongchamps, Eugéne Eudes.
1824.—Filaire. Filaira, Encycl. Méthodique, vol. 2, pp. 391-397.
RELATION OF INSECTS TO THE PARASITIC WORMS 91
Dutton, J. Everett.
1905.—The intermediary host of Filaria eupiets (Annett, Dutton, El-
liott); the Filaria of the African swift, Cypselus affinis.
Thompson Yates & Johnston Lab. Rep., Lond., n. s., vol. 6,
No. 1, Jan., pp. 137-147, pl. 5, figs. i-x.
Feldmann.
1905.—Ueber Filaria perstans im Bezirk Bukoba. Arch. f. Schiffs- u
Tropen-Hyg., vol. 9, No. 2, Feb., pp. 62-65, 2 pls.
Fibiger, Johannes, and Ditlevsen, Hjalmar.
1914.—Contributions to the biology and morphology of Spiroptera
(Gongylonema) neoplastica n. s. Mindeskr. Japetus Steen-
strups Fodsel, 2. Halvbind, 28 pp., figs. 1-3, pls. 1-4, figs. 1-32.
Fiilleborn, Friedrich.
1908.—Ueber Versuche an Hundefilarien und deren Ubertragung durch
Miicken. Beihefte (8) z. Arch. f. Schiffs- u. Tropen-Hyg.,
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1-38.
1908.—Untersuchungen an menschlichen Filarien und deren Uber-
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Tropen-Hygr., vol. 12, Nov., pp. 357-388 (36 pp.), figs. 1-3,
pis. 1-7, figs. 1-132.
1913.—Die Filarien des Menschen. MHandb. d. path. Mikroorganism.
(Kolle & Wassermann), Jena, 2. Aufl., vol. 8, pp. 185-344, figs.
1-41, pls. 1-6.
Galeb, Osman.
1878.—Observations et expériences sur les migrations du Filaria
rytipleurites, parasite des blattes et des rats. Compt. Rend.
Acad. Sc., vol. 87, No. 2, July 8, pp. 75-77.
Grassi, Giovanni Battista.
1887.—Entwickelungscyklus der Tania nana, Dritte préliminarnote.
Centralbl. f. Bakteriol. (etc.), Jena, 1. Jahr., vol. 2, No. 11,
pp. 305-312,
1888.—Ciclo evolutivo della Spiroptera (Filaria) sanguinolenta. Gior.
di Anat., Fisiol. e Patol. d. Animali, vol. 20, No. 2, Mar.-Apr.,
pp. 99-101.
Grassi, Giovanni Battista, and Calandruccio, Salvatore.
1888.—Ueber einen Echimorhynchus, welcher auch im Menschen para-
sitirt und dessen Zwischenwirth ein Blaps ist. Centralbl. f.
92 SANITARY ENTOMOLOGY
Bakteriol. (etc.), Jena, 2. Jahr., vol. 3, No. 17, pp. 521-525,
figs. 1-7.
1890.—Ueber Haematozoon Lewis. Entwickelungscyklus einer Filaria
(Filaria recondita Grassi) des Hundes. Centralbl. f. Bakteriol.
(etc.), Jena, vol. 7, No. 1, Jan. 2, pp. 18-26, figs. 1-16.
Grassi, Giovanni Battista, and Rovelli, Giuseppe.
1888.—Intorno allo sviluppo cestodi. Nota preliminare. Atti R.
Accad. d. Lincei, Roma, Rendic., an. 285, 4. s., vol. 4, 1.
semestre, No. 12, June 3, pp. 700-702.
1888.—Bandwiirmerentwickelung. Centralbl. f. Bakteriol. (etc.),
Jena, 2. Jahr, vol. 3, No. 6, p. 173.
1889.—Sviluppo del cisticerco e del cisticercoide. Nota preliminare.
Atti R. Accad. d. Lincei, Roma, Rendic., an. 286, 4. s., vol.
5, 1. semestre, No. 3, Feb. 3, pp. 165-174, figs. 1-4.
1892.—Ricerche embriologiche sui cestodi, Atti Accad. Giornia di
Sc. Nat. in Catania (1891-92), an. 68, 4. s., vol. 4, 2, mem., 108
pp-, & pls.
Gruby, David, and Delafond, Henri-Mamert-Onesius,
1843.—Note sur une altération vermineuse du sang d’un chien déter-
minée par un grand nombre d’hématozoaires du genre filaire.
Compt. Rend. Acad. Sc., vol. 16, No. 6, Feb. 6, pp. 325-326.
Guberlet, John E.
1916.—Morphology of adult and larval cestodes from poultry. Trans.
Am. Micr. Soc., vol. 35, No. 1, Jan., pp. 23-44, pls. 5-8, figs.
1-30.
1919.—On the life history of the chicken cestode, Hymenolepis carioca
(Magalhaes). Journ. Parasit., vol. 6, No. 1, Sept., pp.
35-38, pl. 4, figs. 1-6.
Hill, Gerald F.
1918.—Relationship of insects to parasitic diseases in stock. Pp. 11-
107, pls. 2-8, figs. 1-49A. 8°. Melbourne. [Reprint from
Proc. Roy. Soc. Victoria, new ser., v. 31, pt. 1.]
Hodges, Aubrey.
1902.—Sleeping-sickness and Filaria perstans in Busoga and its neigh-
borhood, Uganda Protectorate. Journ. Trop. Med., vol. 5, No.
19, Oct. 1, pp. 293-300, 1 map, 1 pl., figs. 1-2.
Johnston, T. Harvey. ;
1913.—Notes on some Entozoa. Proc. Roy. Soc. Queensland, vol. 24,
pp. 63-91, pls. 2-5, figs. 1-45. (Advance separate issued Nov.
1, 19129).
RELATION OF INSECTS TO THE PARASITIC WORMS 93
Joyeux, Ch. ‘
1916.—Sur le cycle évolutif de quelques cestodes. Note préliminaire.
Bull. Soc. Path. Exot., vol. 9, No. 8, Oct. 11, pp. 578-583.
Kleine, F. K.
1915.—Die Ubertragung von Filarien durch Chrysops. Zeitschy. f.
Hyg. u. Infektionskrankh., vol. 80, No. 3, Oct. 26, pp. 345-549.
Lebredo, Mario G.
1904.—Filariasis. Nota preliminar deducida de experiencias practicas,
que demuestran el sitio por donde la Filaria noctwrna abandona
el Culex pipiens infectado. Rev. Med. Trop., Habana, vol. 5,
No. 11, Nov., pp. 171-172.
1905.—Metamorphosis of Filaria in the body of the mosquito (Culex
pipiens). Journ. Infect. Dis., Suppl. (1), May, pp. 332-
352, pls. 1-3, figs. 1-16.
Leiper, Robert T.
1913.—[Metamorphosis of Filaria loa.] ['Telegram to London School
Trop. Med., Dec. 27, 1912]. Lancet, No. 4662, vol. 184,
vol. 1, No. 1, Jan. 4, p. 51.
Leuckart, Karl Georg Friedrich Rudolph.
1867.—Die menschlichen Parasiten und die von ihnen herriihrenden
Krankheiten. Ein Hand- und Lehrbuch fiir Naturforscher und
Aerzte. Vol. 2, 1. Lief., vi, 256 pp., 158 figs. Leipzig & Heidel-
berg.
Low, George C.
1902.—Notes on Filaria demarquaii. Brit. Med. Journ., No. 2148,
vol. 1, Jan. 25, pp. 196-197.
1903.—Filaria perstans. Brit. Med. Journ., No. 2204, vol. 1, Mar. 28,
pp. 722-724, figs. 1-2.
Manson, (Sir) Patrick.
1878.—On the development of Filaria sanguinis hominis, and on the
mosquito considered as a nurse. Journ. Linn. Soc. Lond.,
Zool. (75), vol. 14, Aug. 31, pp. 304-311.
Marchi, Pietro.
1867.—Monografia sulla storia genetica e sulla anatomia della
Spiroptera obtusa Rud., 34 pp., 2 pls. fol. Torino. [ Advance
separate from Mem. R. Accad. Sc. Torino, Cl. d. Sc. Fis., Mat.
e Nat., 2. s., vol. 25, issued in 1871.]
94 SANITARY ENTOMOLOGY
Melnikov, Nicolaus.
1869.—Ueber die Jugendzustinde der Tenia cucwmerina. Arch. f.
Naturg., Berl., 35. Jahr., vol. 1, No. 1, pp. 62-70, pl. 3, figs.
a-c.
Nickerson, W. S.
1911.—An American intermediate host for Hymenolepis diminuta,
Science, n. s., No. 842, vol. 33, Feb. 17, p. 271.
Nicoll, W., and Minchin, E. A.
1911.—Two species of cysticercoids from the rat-flea (Ceratophyllus
fasciatus). Proc. Zool. Soc. Lond., No. 1, Mar., pp. 9-13,
figs. 1-2.
Noé, Giovanni.
1900.—Propagazione delle filarie del sangue esclusivamente per mezzo
della puntura della zanzare. 2. Nota preliminare, Atti R.
Accad. d. Lincei, Rendic. Cl. di Sc. Fis., Mat. e Nat., an. 297,
5. s., vol. 9, 2. semestre, No. 12, Dec. 16, pp. 357-362, figs. 1-3.
1903.—Studi sul ciclo evolutivo della Filaria labiato-papillosa, Ales-
sandrini. Nota preliminare. Atti R. Accad. d. Lincei, Rendic.
Cl. di Sc. Fis., Mat. e Nat., an. 300, 5. s., vol. 12, 2 semestre,
No. 9, Nov. 8, pp. 387-393.
1907.—La Filaria grassii, n. sp. e la Filaria recondita, Grassi. Nota
preliminare. Atti R. Accad. d. Lincei, Rendic. Cl. di Se. Fis.
Mat. e Nat., an. 304, 5. s., vol. 16, 2. semestre, No. 12, Dec.
15, pp. 806-810.
1908.—I ciclo evolutivo della Filaria grassii, mihi, 1907. Atti R.
Accad, d. Lincei, Rendic. Cl. di Sc. Fis., Mat. e Nat., an. 305,
5. s., vol. 17, 1. semestre, No. 5, Mar. 1, pp. 282-293, figs. 1-4.
Nuttall, George H. F.
1899.—On the réle of insects, arachnids, and myriapods as carriers
in the spread of bacterial and parasitic diseases of man and
animals. A critical and historical study. Johns Hopkins
Hosp. Rep., Baltimore, vol. 8, Nos. 1-2, pp. 1-154, pls. 1-3.
Piana, Giovanni Pietro.
1897.—Osservazioni sul Dispharagus nasutus Rud. dei polli e sulle
larve nematoelmintiche delle mosche e dei porcellioni. Atti
Soc. Ital. Sc. Nat. (etc.), Milano, vol. 36, No. 3-4. Feb., pp.
239-262, figs. 1-21.
RELATION OF INSECTS TO THE PARASITIC WORMS 95
Ransom, Brayton H.
1911.—The life history of a parasitic nematode—Habronema muscae.
Science n. s., No. 881, vol. 34, No. 17, pp. 690-692.
1913.—The life history of Habronema muscae (Carter), a parasite
of the horse transmitted by the house fly. U.S. Dept. Agric.,
Bureau Animal Indust., Bull. 163, Apr. 3, pp. 1-36, figs. 1-41.
Ransom, Brayton H., and Hall, Maurice C.
1915.—The life history of Gongylonema scutatum. Journ. Parasit.,
vol. 1, No. 3, Mar., p. 154.
1916.—The life history of Gongylonema scutatum. Journ. Parasit.,
vol. 2, No. 2, Dec., 1915, pp. 80-86.
1917.—A further note on the life history of Gongylonema scutatum.
Journ. Parasit., vol. 3, No. 4, June, pp. 177-181.
Ringenbach, J., and Guyomarc’h.
1914.—La filariose dans les régions de la nouvelle frontiére Congo-
Cameroun. Observations sur la transmission de Microfilaria
diurna et de Microfilaria perstans. Bull. Soc. Path. Exot.,
vol. 7, No. 7, July 8, pp. 619-626.
Robles, R.
1919.—Onchocercose humaine au Guatémala produisant la cécité et
“Vérysipéle du littoral” (erisipela de la costa). Bull. Soc.
Path. Exot., vol. 12, No. 7, July 9, pp. 442-460, 2 maps,
figs. 1-6.
Seurat, L. G.
1912.—Sur le cycle evolutif du spiroptére du chien. Compt. Rend.
Acad. Sc., vol. 154, No. 2, Jan. 8, pp. 82-84.
1912.—La grande blatte, héte intermédiaire de 1’échinorhynque
moniliforme en Algérie. Compt. Rend. Soc. Biol., vol. 72, No.
2, Jan. 19, pp. 62-63.
1913.—Sur Vévolution du Physocephalus sexalatus (Molin). Compt.
Rend. Soc. Biol., vol. 75, No. 35, Dec. 12, pp. 517-520, figs.
1-4.
1913.—Sur lévolution du Spirwra gastrophila Mill. Compt. Rend.
Soc. Biol., vol. 74, No. 6, Feb. 14, pp. 286-289, figs. 1-3.
1916.—Contribution 4 l’étude des formes larvaires des nématodes
parasites hetéroxénes. Bull. Scient. France et Belg., 7. s.,
vol. 49, No. 4, July 6, pp. 297-377, figs. 1-14.
1918.—Extension de Vhabitat du Spirura gastrophila (Mueller).
Compt. Rend. Soc. Biol., vol. 81, No. 15, July 27, pp. 789-791.
96 SANITARY ENTOMOLOGY
1919.—Contributions nouvelles a l’étude des formes larvaires des
nématodes parasites hétéroxénes.. Bull. Biol. France et Belg.
(1918), vol. 52, No. 4, Mar. 25, pp. 344-878, figs. I-XII.
Theiler, (Sir) Arnold,
1919.—A new nematode in fowls, having a termite as an intermediary
host. [Filaria gallinarwm (nova species) ]. 5. & 6. Rep.
Director Vet. Research, Dept. Agric. Union South Africa
(1918), Apr., pp. 695-707, 1 pl., fig. 1.
Van Saceghem, R.
1917.—Contribution a étude de la dermite granuleuse des equidés.
Bull. Soc, Path, Exot., vol. 10, No. 8, Oct., pp. 726-729.
1918.—Cause étiologique et traitement de la dermite granuleuse.
Bull. Soc. Path. Exot., vol. 11, No. 7, July 10, pp. 575-578.
Villot, Francois Charles Alfred.
1878.—Migrations et métamorphoses des ténias des musaraignes.
Ann. Sc. Nat., Zool., vol. 49, 6. s., vol. 8, Nos. 2-3, art. 5, 19
pp., pl. 11, figs. 1-14.
1883.—Mémoire sur les cystiques des ténias. Ann. Sc. Nat., Zool., 6. s.,
vol. 15, art. 4, Oct., 61 pp., pl. 12, figs. 1-13.
Von Linstow, Otto Friedrich Bernhard.
1886.—Ueber den Zwischenwirth von Ascaris lumbricoides L. Zool.
Anz., No. 231, vol. 9, Aug. 30, pp. 525-528.
Von Stein, Friedrich.
1852.—Beitriige zur Entwickelungsgeschichte der Eingeweidewiirmer.
Zeitschr. f.. Wissensch. Zool., vol. 4, No. 2, Sept. 2, pp. 196-
214, pl. 10, figs. 1-20,
Wellman, Frederick Creighton,
1907.—Preliminary note on some bodies found in ticks Ornithodoros
moubata (Murray) fed on blood containing embryos of Fi-
laria perstans (Manson). Brit. Med. Journ., No. 2429, vol.
2, July 20, pp. 142-143.
CHAPTER VI
The Relations of Climate and Life and Their Bearings on the Study of
Medical Entomology.*
W. Dwight Pierce
All animal and plant life has its being and reacts according to defi-
nite laws in which we find the climatic factor of primary importance.
We cannot go far into a subject with as many inter-relationships as
medical entomology without finding it necessary to know something of
the climatic laws which govern the lives of the various organisms con-
cerned.
In several of the lectures attention is especially called to apparent
discrepancies in the interpretation of climatic effects on the life of the
insects, and this is particularly true in case of the lice. Throughout
our literature there is to be found a hazy notion of the importance of
temperature and still hazier notions of humidity. There is a great’
deal about these factors which help to govern life, that no one knows,
but it will pay us to have a clearly defined statement of some of the
most important principles as now understood.
On a proper understanding of the relations of temperature and
humidity to the life and development of insects, animals, and disease
organisms, depend all transmission experiments, all efforts in keeping
alive the various creatures involved, all interpretations of results and
many practical measures of control.
This difficult subject will be stated in as simple language as possible
so that all may see the basic principles at least.
Every one of us knows that cold and heat can cause pain. We have
indeed a clear understanding that cold and heat kill. We recognize the
fact that we seem to work best under conditions when we are absolutely
oblivious of heat or cold, dryness or moisture. We have felt stupid
in murky weather. We have felt parched and dried from extremely
dry weather. In other words, we can now recognize four conditions
which may affect our well-being, cold, heat, dryness, moisture. These
can be expressed on two scales—temperature and relative humidity. In
other words, we should be able to chart our own susceptibilities to these
factors by running, for example, a temperature scale vertically on our
1This lecture was read July 1, 1918 and issued the same day.
97
98 SANITARY ENTOMOLOGY
chart paper and a humidity scale from zero to one hundred per cent-
saturation horizontally.
If we picture our reactions or those of the creature being studied
on such a chart (see figs. 8, 9), we will better understand the subject.
In the lower part of the chart we will locate certain temperatures which
always cause death from cold. These may be known as ABSOLUTE
FATAL TEMPERATURES.
Now a common failing in the past has been to assume that humidity
had nothing to do with the effect of temperature on life. It does have
a very decided bearing. A creature which can stand a certain degree
3
*
wa :
MEAN TEMPERATURE
THERMONOCHES
ones suazongA
z
pPOKERAENOSIS -Dariy, ip
ZONE OF GREATEST
ACTIVITY,
retin,
NE OF a ‘
aw bs
RHIGOPLEGIA-
2 & &
Dicaees Faereanesy
PERCENTAGE MEAN AUMIDITY. ww
“” 2. * te
AN HYPOTHETICAL CHART SHOWING THE ZONES OF LIFE REACTIONS TO
TEMPERATURE AND RELATIVE HUMIDITY, DIFFERING FOR EACH SPECIES.
Fic. 8
of cold at a given humidity may be absolutely unable to stand that same
temperature at another degree of saturation or relative humidity.
Our absolutely fatal temperatures therefore will form some sort of
a zone on our chart and this zone will probably be bounded by a curve.
We call the temperatures below this curve the LOWER ZONE OF
FATAL TEMPERATURES. Death caused by cold is called RHIGO-
PLEGIA.
Slightly above these absolutely fatal temperatures will be a zone of
temperatures which might cause death if experienced sufficiently long,
but which at least cause a complete suspension of all activity. And
still higher will be temperatures which also cause suspension of activity,
but which do not cause death even when experienced for very long pe-
RELATIONS OF CLIMATE AND LIFE 99
riods. Formerly, this suspension of activity by animal life on account
of cold was called hibernation, which means winter rest. The writer has
shown (Pierce, W. D., 1916, Journ. Agr. Res., vol. 5, pp. 1183-1191)
that this same inactivity may be caused by dryness or heat and possibly
by excessive humidity, and that a creature may remain in the same
state of inactivity from the heat of summer through the cold of winter
and be awakened from it only by the addition of a requisite amount
of moisture at effective temperatures. We must seek other terms than
hibernation, or winter rest, and aestivation, or summer rest. As this
rest consists essentially of an almost complete cessation of all bodily
functions, and is a state of insensibility, we may very properly designate
the so-called hibernation as RHIGANESTHESIA, or insensibility due
to cold. This state may be acquired naturally as winter sets in, or may
be artificially induced at any time of the year by lowering the tempera-
ture. The temperatures inducing RHIGANESTHESIA are grouped
into the LOWER ZONE OF INACTIVITY, or the ZONE OF RHIG-
ANESTHESIA.
As the temperatures increase, a creature in the state of rest or
rhiganesthesia, commences to show slow movements of the body fluids,
and slight jerky motions, which increase with increase of temperature.
This awakening or anastasis, when caused by temperature change, is a
THERMANASTASIS.
The approximate point at any given humidity at which thermanastasis
begins is the ZERO OF EFFECTIVE TEMPERATURE. It must be
. firmly fixed in your minds that there is not a single zero of effective
temperature, as so often claimed, but a different one for every degree or
portion of a degree of relative humidity. In other words, at one humidity
the awakening may occur at one temperature, and under other conditions
of humidity the temperature may be considerably higher or lower. These
points can be connected by a curve which represents the lower limit of
the ZONE OF ACTIVITY, or the THERMOPRACTIC ZONE, mean-
ing a zone of effective temperatures.
Many authors have manifested considerable confusion in their writ-
ings and have even claimed that other authors were incorrect because a
certain developmental period or reaction was accomplished in their ex-
periments at a given temperature in a certain period of time while the
other investigators obtained totally different results. A man working
in a moist coastal section could not justly compare his results with those
of a man working in a drier section unless the conditions of humidity were
recorded also. For this reason, the writer has maintained that labora-
tories attempting to correlate temperature with life history, must at least
be equipped with maximum and minimum thermometers and a sling
psychrometer for determining humidity, and that accurate results are
100 SANITARY ENTOMOLOGY
based only on a recording hygrothermograph, checked by the above
mentioned instruments.
The great bulk of work naturally is upon the reactions which take
place in the zone of activity.
It must not be forgotten, however, that control work depends often
upon a correct knowledge of the lower zone of fatal temperatures, and
that successful storage of breeding material, until the investigator is
ready to use it, depends often upon a knowledge of the requirements of
rhiganesthesia.
Following the awakening, the body takes up all its natural functions
and we must assume that sustenance is available. The first activities,
at temperatures just above the zero of activity, are naturally very
sluggish and this state of sluggishness may be known as RHIGO-
NOCHELIA, or sluggishness caused by cold.
Some creatures are very sensitive to cold, usually when the humidity
is high. Pain produced by the application of cold is called CRYAL-
GESIA. An abnormal sensitiveness to cold is known as CRYESTHESIA,
and a morbid sensitiveness as HYPERCRYALGESIA. These sensa-
tions are probably only experienced with a descent of temperatures.
In the zone of effective temperatures or thermopractic zone there
is a point or a small restricted zone of temperatures at which all activi-
ties are most effective, that is, the greatest amount of work is accom-
plished with the least amount of exertion and the least loss of energy.
This is the so-called OPTIMUM, or perhaps better, PRACTICOTATUM,
meaning most effective. As temperatures ascend to the practicotatum
any given function is performed in proportionately shorter time. As
the temperatures ascend above the practicotatum a particular function
may be exercised more rapidly but less accurately or less effectively, as
for instance, more eggs may be laid but fewer hatch: but the activity is
feverish and soon exhaustion takes place, or the individual gradually
becomes more stupid and sluggish. This heat sluggishness is therefore
called THERMONOCHELIA.
Different reactions to heat may be experienced and these have all
received appropriate designations. As for example, a stifling sensation
is called THERMOPNIGIA; an unusual sensibility to heat THERMAL-
GESIA, and a more intense sensibility HYPERTHERMALGESIA. The
ability to recognize changes of temperature is THERMESTHESIA,
and its extreme is designated as THERMOHYPERESTHESIA, an
abnormal sensitiveness to heat stimuli. A fondness for heat or requiring.
great heat for growth is called THERMOPHILIC, while resistance to
heat is called THERMOPHYLIC. Wher a stifling temperature is ex-
perienced rapid breathing or THERMOPOLYPNEA is often experi-
enced. Contraction under the action of heat is designated as 'THER-
y
RELATIONS OF CLIMATE AND LIFE 101
MOSYSTALTIC. The adaptation of the body temperature to that of
the environment is PECILOTHERMAL. A morbid dread of heat is
THERMOPHOBIA. The determination of the direction or rate of
locomotion by heat is called THERMOTAXIS and movement brought
about by heat is THERMOTROPISM.
As the temperatures increase sluggishness increases until sleep or
inactivity is induced and this condition once known as aestivation or
summer rest may better be known as THERMANESTHESIA or insensi-
bility caused by heat.
The point at which anesthesia begins at any given humidity is the
upper boundary of the thermopractic or effective zone. Those tempera-
tures at which successful Thermanesthesia may be experienced embrace
the UPPER ZONE OF INACTIVITY, or the ZONE OF THERM-
ANESTHESIA. This quickly merges into those high temperatures which
may with sufficient duration of time cause death, and finally, those tem-
peratures which are absolutely fatal under all conditions. ‘The highest
zone is therefore the UPPER ZONE OF FATAL TEMPERATURES.
Death from heat is known as THERMOPLEGIA, or heat stroke.
Most investigators have stopped with a more or less hazy acknowledg-
ment of the existence of these various zones of reactions on the ascend-
ing scale of the thermometer, but the literature contains few references
to similar zones of reactions on the scale of relative humidity. However,
if we stop to think we must acknowledge that similar reactions do take
place.
We may have death from absolute dryness at almost any tempera-
ture, in other words, we have a condition which is called APOXERAE-
NOSIS, or drying up. At very low humidities one may become insensi-
ble and thus we have XERANESTHESIA. Likewise, a little higher
humidity induces sluggishness or a state of KERONOCHELIA. We
have most of us experienced this condition of stupidity in a living room
at normal temperatures in the winter due to lack of sufficient moisture.
So also there is the humidity which enables each individual to accom-
plish the greatest results in the least time with the least amount of
exhaustion and this is the PRACTICOTATUM. With increase of
humidity the activity lessens until an excessively humid atmosphere
brings about HYGRONOCHELIA or sluggishness due to moisture; then
HYGRANESTHESIA may be experienced by some species and finally
death due to excessive moisture or HYGROPLEGIA.
This makes it obvious therefore that when we plot the reactions
of a species to temperature and humidity, we are likely to find a series
of closed figures delineating concentric zones of fatal, inactive, active
and optimum conditions. Thus it is apparent that Rhigoplegia,
Apoxeraeriosis, Thermoplegia, and Hygroplegia form a single zone of
102 SANITARY ENTOMOLOGY
temperature-humidities which cause death—this whole zone is the fatal
or OLETHRIC ZONE. All conditions of life lie within it, the next zone
being that which includes Rhiganesthesia, Xeranesthesia, Thermanes-
thesia, and Hygranesthesia; the whole zone therefore being the ANES-
THETIC ZONE, or zone of rest, which includes the conditions known
as hibernation and aestivation. Within this is the THERMOPRACTIC
ZONE or zone of effective temperatures, which is naturally made up of
sub-zones representing degrees of activity, as the NOCHELIC SUB-
ZONE of sluggish activities on the outside and the PRACTICOTATUM
at the center.
PERCENTAGE «MEAN MUMIDITY.
2 ®
a » 2 od
SUCCESTED CURVES OF THE RESPONSES OF AVERAGE AMERICANS TQ HUMID A
TEMPERATURES WITH CERTAIN ACTUAL RECORDS SERVING AS A BASIS.
Fig. 9
Temperature and humidity affect every bodily function of every
creature of the plant and animal kingdom. Some creatures may love
cold, some heat, some dryness, some moisture. The pattern of their
reactions will therefore shift from one place to another on the chart.
Some creatures may be so resistant to cold that fatal temperatures are
never normally experienced and rarely artificially. Some may be very
resistant to dryness and others capable of standing any degree of hu-
midity. In case of plants the root system receives one set of stimuli
and the upper portion another, so that the interpretation is not as
simple as with animals.
In the different stages of growth a creature may have different abil-
ity to withstand extremes.
If the approach to unfavorable or noneffective conditions is gradual,
RELATIONS OF CLIMATE AND LIFE 103
the body gradually adjusts and adapts itself for entrance into a dormant
state. We find adaptations against cold, heat and dryness, often in
cysts or in cases constructed by the creature, and in fact some of these
protective cases are made of substances impervious to water. In the
state of encystment far greater extremes can be experienced than in
the normal state, because of the impervious nature of the cyst.
Successful dormancy often depends upon the rapidity with which
it was brought about. Most creatures practically free the intestinal
canal before entering a resting stage.
A sudden lowering or raising of temperature may be fatal at tem-
peratures which would normally be easily withstood if approached grad-
ually.
Alternation of high and low temperatures, if sudden, is often fatal
at normally effective temperatures. A creature may become dormant
with descending temperatures at a higher temperature than it would
awaken with ascending temperatures.
A continuous maintenance of an even temperature and humidity is
more or less enervating. A climate which has sufficient variation to
allow certain periods of rest from cold at night and heat in the day
is probably productive of better results. It is possible in a given day
for a creature to have two active and two dormant periods. As for
example, observations of many insects will show that they sleep during
the cold parts of a night, are active during the morning, sleep during
the hottest part of the day, are again active in the evening and early
parts of the night. It is also noticeable that on humid days many in-
sects are inactive but as soon as the air dries they again resume activ-
ity, and the reverse is found in arid regions.
Many investigators have failed in keeping insects alive for experi-
ment because of failure to keep sufficient water present for drinking
purposes and maintenance of proper humidity.
As long as any creature is experiencing effective temperatures it
must have food available to take when needed and this food must be in
proper condition. Long periods without food at noneffective tempera-
tures can be experienced, but at effective temperatures the length of
life is relatively short. This is a very important point in control work
with all insects. If you can deprive them of food for a sufficient period
when the climatic conditions enforce activity, then control is easy.
There are many very difficult points in this question. Inasmuch
as noneffective temperatures and also noneffective humidities may be
experienced each day, it becomes necessary to make elaborate studies
to ascertain the boundaries of the thermopractic and hygropractic zones,
and only a thermo-hygrograph record sheet will enable one to make any
kind of a satisfactory study.
104 SANITARY ENTOMOLOGY
There is a rule which receives much support, that a given reaction
or stage of development is accomplished at an almost constant total
effective temperature, which is the multiple of time units by temperature
units accumulated above the zero of effective temperature. Since the
zero varies with the humidity, the total effective temperature obtained
by this rule does likewise. We must therefore reword the rule to read:
A given reaction or stage of development is accomplished at any given
mean humidity at a constant total effective temperature, which is the
multiple of effective time units by temperature units accumulated within
the zone of effective temperatures at a given atmospheric pressure.
To compute this one must first eliminate all time, temperature,
and humidity which was noneffective, whether at the top or bottom of the
scale. For instance, if at 60% humidity the temperatures 65° to 85°
are effective, and during the day the temperature ranged from ‘50° to 90°,
but only during eight hours at the effective temperatures; we must
multiply the period 8 hours by the mean temperature experienced be-
tween 65° and 85°, considering 65 as 0 and 85 as 20. The result is
the total effective temperature of that day. Adding these total effective
temperatures during the total period of the stage, we obtain the total
effective temperature necessary to bring about the perfection of the
stage. Necessarily this is a very complicated proposition, requiring
very careful computations. Nevertheless, once worked out we can es-
tablish laws of control which are of utmost value.
Some of the following lectures will refer to the principles laid down
in this lecture and lines of research will be suggested leading toward
control measures. The charts (figs. 8, 9) should be studied in connec-
tion with the lecture.
CHAPTER VII
Diseases Borne by Non-Biting Flies ?
W. Dwight Pierce
It will be necessary in discussing the réle of flies in the transmission:
of disease to divide the flies into several categories, because so many
species of the order Diptera are involved. The flies can be divided
into two large groups, those which bite and those which do not bite,
but, rather, sip their food. Two excellent monographs on the relations
of flies and disease have been published, that on the non-bloodsuckers by
Graham-Smith, and that on the bloodsuckers by Hindle.
This lecture deals with the non-biting flies only. Among these flies
are to be found the principal house-visiting flies, foremost among which
is the house or typhoid fly, Musca domestica Linnaeus, followed by the.
blue bottle blow flies, Calliphora vomitoria Linnaeus and C. erythro-
cephala Meigen, the green bottle blow fly Lucilia caesar Linnaeus, and.
various other species. The mouth parts of these flies are constructed
only for sucking or sipping liquid or semi-liquid foods.
In this lecture can only be given a very condensed statement of the
relationship of these flies to disease. A more extensive study should.
involve the reading of the books by Hewitt and Graham-Smith quoted.
in the bibliography. In these volumes the evidence is given in great
detail.
Among the most striking of the investigations into the capacity of
non-biting flies for the carriage of disease germs, are a series of three.
excellent papers by the Italian investigator, Cao, whose work is over-
looked by many subsequent writers. In fact, there has been but one.
good review of his results in English.. And yet his investigations opened.
up the way for practically all of the work on bacterial transmission by
insects. Working with larvae and adults of Musca domestica Linnaeus,
Calliphora vomitoria Linnaeus, Lucilia caesar Linnaeus and Sarcophaga.
carnaria Linnaeus, he proved that the larvae of these flies could take
up and pass through their intestines any bacteria occurring in their:
food, and that all four species acted exactly alike in this regard. Except
where he specifically stated, his results applied to all four species in
1This lecture was presented in two parts on July 8 and 15 and distributed entire.
on July 15, 1918. It has been revised for this edition.
105
106 SANITARY ENTOMOLOGY
every instance. Step by step, he proved that fly-larve take up bacteria
from their food, and when breeding in flesh may take up disease germs as
well as non-pathogenic germs; that these germs may pass unaltered
through the insects’ intestines and out in their feces; that some of them
may remain for a long period in the intestinal canal, and some even
may multiply therein; that they may be taken up by the larva and per-
sist through its metamorphosis until it arrives at the adult stage, and
for days thereafter, and may be carried by this adult and deposited
with its feces on food or excrement; and that these bacteria will also be
fownd in the glutinous substances surrounding the eggs when deposited,
and thus contaminate the substance in which the newly born larvae will
feed; and of course be taken up by this second generation and possibly a
be distributed farther by it.
These facts were worked out by Cao in 1905 and 1906, and yet
Graham-Smith credits Faichnie (who worked in India in 1909) with be-
ing the first one to suggest that bacteria ingested by the larva might
survive the pupal stage and be present in the intestine of the adult.
Later, Bacot, and also Ledingham in 1911 and Graham-Smith in 1912,
corroborated these claims that the bacteria could persist in the body
throughout the metamorphosis.
Ledingham (1911), Nicholls (1912), and Graham-Smith (1912)
have shown that the fly larve have great powers of destroying micro-
organisms due to the fact that many of these organisms are not adapted
to the conditions prevailing in the interior of the larva and pupa, or
perhaps more correctly due to the hostile action of bacteria which more
normally frequent the intestines of the larve. These normal inhabitants
of the fly intestine are principally non-lactose fermenting organisms.
Not only bacteria but also protozoa, such as the amoebae of dysen-
tery, and the eggs of parasitic worms, may be taken up by the fly larve or
adults and deposited in the feces. Roubaud (1918) has brought out
the fact that multitudes of the amoebic dysentery germs taken up by
adult flies and deposited in their feces die because of the rapid drying
of the feces, and he credits the fly with being a great agent in the de-
struction of multitudes of protozoa, while granting the equally great
opportunity of the fly to contaminate food therewith.
Stiles in 1889 fed larve of Musca domestica with female Ascaris
lumbricoides, which they devoured, together with the eggs they con-
tained. The larvae as well as the adult flies contained the eggs of
Ascaris (Nuttall, 1899, p. 39). Nicoll (1911) has very thoroughly in-
vestigated the relationships of flies to the possible carriage of eggs of
worms and demonstrated the ability of adult flies to ingest the eggs of
various species of worms, provided these are small enough, and to pass
DISEASES BORNE BY NON-BITING FLIES 107
them out whole in the feces, but in all his experiments with the larvae he
found that the eggs were crushed.
In addition to the ability of flies to carry disease germs in their
body, there are multitudes of proofs of their ability to carry them also
on their body and to deposit them when they feed.
The transmission of disease by non-bloodsucking flies is exclusively
by contamination either of food, water or wounds. Most of the flies
which frequent houses and food or visit man because of attractive secre-
tions or injuries also are attracted to and breed in excreta or garbage.
Hence the contamination of food by direct transportation from infected
excreta is a very simple matter.
This contamination may be by the simple depositing of disease
germs carried on the body of the flies, or by regurgitation, or the
deposition of feces. Wherever a fly alights and remains a few minutes
it deposits either vomit or feces. By the nature of its breeding it is
hardly to be expected that these deposits will not contain some kind of
bacteria, and possibly protozoa or worm eggs. If these deposits are
made on the moist media. offered by foods the germs may easily retain
their virulence until eaten.
As flies can travel considerable distances, at least thirteen miles,
the existence of a single disease case with insanitary conditions in the
vicinity enabling fly breeding, might easily infect an entire city or army
camp if the flies were permitted to reach the food of the inhabitants. It
is because of the total lack of sanitary waste disposal in country dis-
tricts that diseases like typhoid fever and dysentery usually become very
widespread. We can not know the source of the flies which enter our
houses. We must not let them visit our food. They must be kept away
from the eyes and mouths of babies. Our markets where meats and
vegetables are sold must be better protected. Only through influencing
public opinion will we be able to have the fly nuisance in our own public
markets abated. Food offered for sale should be kept under glass or
screen at all times.
There are so many organisms transmitted by the non-blood-sucking
flies that we shall have to deal with them rather briefly and preferably
according to their classification. A thorough digest of the mass of
matter submitted below should impress the readers with the necessity
of fly prevention.
PLANT ORGANISMS CARRIED BY NON-BITING FLIES
Thallophyta: Fungi: Schizomycetes: Coccaceae
Streptococcus equinus Andrewes and Horder, a non-pathogenic organ-
ism found in horse dung, was found by ‘Torrey (1912) in a number of
cases on the surface of city caught flies.
108 SANITARY ENTOMOLOGY
Streptococcus fecalis Andrewes and Horder, an organism occurring
normally in the human intestine and occasionally pathogenic has been
isolated from city caught Musca domestica by Scott (1917), Cox, Lewis
and Glynn (1912) and Torrey (1912).
Streptococcus pyogenes Rosenbach, an organism causing ERYSIPE-
LAS, SUPPURATION and SEPTICAEMIA was isolated by Scott
(1917) from city caught Musca domestica in Washington.
Streptococcus salivarius Andrewes and Horder, an organism fre-
quently found in the mouth, but rarely pathogenic, has been isolated from
the intestines of city caught Musca domestica by Torrey (1912), and
was also found on flies by Cox, Lewis and Glynn (1912).
Diplococcus gonorrhoeae Neisser (Gonococcus), the cause of GONOR-
RHOEA, was found by Welander (1896) carried on the feet of a fly
for three hours after they had been soiled with secretion.
Diplococcus intracellularis meningitidis Weichselbaum (Meningococ-
cus), the cause of CEREBROSPINAL MENINGITIS, is thought to be
possibly carried by flies by MacGregor (1917).
Micrococcus flavus was isolated by Torrey (1912) from the intes-
tinal content as well as the surface of city caught flies.
Micrococcus tetragenus Gaffky, commonly found in the human body,
sometimes pathogenic, sometimes saprophytic, was isolated from Musca
domestica by Scott (1917).
Staphylococcus pyogenes albus Rosenbach, a cause of SEPTICAE-
MIA, was isolated by Cao (1906B) from the mucilaginous envelope cov-
ering the eggs of Musca domestica, Sarcophaga vomitoria, Lucilia caesar
and Calliphora vomitoria at the time of deposition. Scott (1917) iso-
lated it from the bodies of Musca domestica.
Staphylococcus pyogenes awreus Rosenbach, a frequent cause of
ABSCESSES, etc., was shown by Celli (1888) to retain its virulence after
passing through the flies’ intestines. Herms (1915) proved by experi-
ment that Musca domestica can carry great numbers of this organism
on its feet. Torrey (1912) and Scott (1917) isolated it from the bodies
of city caught flies. Cao (1906B) isolated it from the eggs at the time
of deposition of laboratory caught flies of Musca domestica, Calliphora
vomitoria, Sarcophaga carnaria and Lucilia caesar.
Staphylococcus pyogenes citreus Passet, a pathogenic, chromogenic,
pus-forming organism, was isolated by Scott (1917) from bodies of
house flies Musca domestica in Washington. Cao (1906B) fed larvae of
Musca domestica, Sarcophaga carnaria, Calliphora vomitoria, and
Lucilia caesar on meat polluted with this organism and recovered it from
the feces of mature flies bred from these larvae.
Sarcina aurantiaca Lindner and Koch, a zymogenic, chromogenic
(orange yellow) organism found in air and water, rarely pathogenic,
DISEASES BORNE BY NON-BITING FLIES 109
was found by Cao (1906B) to be capable of passing through the intes-
tines of larve of Musca domestica, Calliphora vomitoria, Sarcophaga car-
naria, and Lucilia caesar, in all stages of larval growth and of remaining
in the body through pupation to maturity.
Thallophyta: Fungi: Schizomycetes: Bacteriacee
Bacillus of Koch-Weeks, the cause of an acute infectious CONJUNC-
TIVITIS (pink eye), is thought by Castellani and Chalmers (1913, p.
700) to be frequently carried by the little Oscinid gnat, Microneurwm
funicola Meijere, which causes great annoyance by hovering in front of the
eyes and attacking the eyes and ears. The flies may be driven away by the
odor of Odol.
Bacillus A of Ledingham, a nonlactose fermenter from the feces of
children, has been found by Tebbutt (1912) to be normal to the house
fly, Musca domestica, being found on the ova, and in the larve, pupe and
adults, and when fed to the larve survived through the metamorphosis to
the adult stage.
Bacillus of Morgan, which is frequently found in cases of INFAN-
TILE DIARRHEA, has been found in various strains commonly in the
intestines of Musca domestica by Nicoll (1911), Morgan and Ledingham
(1909), Cox, Lewis and Glynn (1912) and Graham-Smith (1912), and
the latter found that when fed to larve of the house fly it could survive
through the metamorphosis to the adult fly.
Bacillus acidi lactici Hueppe, a bacillus common to cows’ milk, has
been isolated from the bodies and from the intestinal contents of Musca
domestica in New York, Washington, London and Liverpool by Torrey
(1912), Scott (1917), Nicoll (1911), and Cox, Lewis and Glynn (1912).
Bacillus aerogenes capsulatus Welch and Nuttall is a pathogenic
organism gaining entrance to the body chiefly through wounds and caus-
ing severe infections resulting often in GANGRENE. In the surgery
of the Great War this organism has been a very important one. It
occurs as a normal inhabitant of the intestine of man and some of the
animals. It has been isolated by Torrey (1912) from the surface as
well as the intestinal contents of city caught flies.
Bacterium anthracis Davaine, the cause of ANTHRAX, although
probably more often carried by biting flies, has been shown by Davaine
(1870) to be capable of carriage by Calliphora vomitoria. He fed flies
on anthracic blood and inoculated guinea pigs with parts of these flies
40 hours to 3 days later, obtaining fatal results in 4 out of 7 cases.
From flies of Calliphora vomitoria caught in his laboratory Cao (1906B)
‘isolated virulent germs of B. anthracis adhering to the glutinous secretion
surrounding the eggs as they were deposited. He later placed on flesh
110 SANITARY ENTOMOLOGY
of animals dead from anthrax externally sterilized eggs of Musca
domestica, Calliphora vomitoria, Lucilia cesar and Sarcophaga carnaria
and from day to day dissected the larve feeding on this flesh, always
demonstrating anthrax germs in their bodies, and he further proved
that these larve retained the germs in their bodies through pupation to
maturity and for at least nine days after maturity. He fed flies on
meat polluted with anthrax and demonstrated twenty-four hours later
the bacilli in the feces and on the eggs. Graham-Smith (1912) found
that many blow flies (Calliphora erythrocephala and Lucilia cesar)
which emerged from larve fed on meat infected with anthrax spores were
infected and remained so for 15 days or more. He also found that a large
proportion of house flies (Musca domestica) which develop from larve
fed on spores of B. anthracis are infected. Because of the habit of blow
flies of breeding in and attacking wounds there have been many cases
of human anthrax on the battle front in Europe. The ease with which
this may occur is quite evident in view of the above quoted investigations.
Bacillus cloace Jordan has been found in the alimentary canal of
Musca domestica in London by Nicoll (1911).
Bacillus coli Escherich, an organism normally found in the alimentary
canal of man, but often found causing secondary infections, was found
by Cao (1906B) in various strains adhering to the eggs at the time of
oviposition of flies caught in the laboratory (Musca domestica, Sarco-
phaga carnaria, Lucilia cesar, and Calliphora vomitoria).
Bacillus coli anaérogenes was isolated by Scott (1917) from Musca
domestica caught in Washington.
Bacillus coli communior Dunham, an abundant inhabitant of the
human and animal intestine, has been isolated from the body and intes-
tinal contents of Musca domestica in New York and Washington by
Torrey (1912) and Scott (1917).
Bacillus coli communis Escherich, an organism common in the intes-
tine of man and animals and associated with a large variety of lesions,
has been isolated from the body and intestinal contents of Musca
domestica by Torrey (1912), Nicoll (1911), Scott (1917) and Cox,
Lewis and Glynn (1912).
Bacillus coli mutabilis was found on the body and in the intestines
of Musca domestica in London by Nicoll (1911).
Bacillus “colisimile’ Cao was fed by. Cao (1906B) to larve of Musca
domestica, Calliphora vomitoria, Lucilia cesar and Sarcophaga carnaria
in flesh and he later demonstrated its abundant presence in the feces of
the larve.
Bacillus cuniculicida Koch and Gaffky, the cause of SEPTICEMIA
in rabbits and guinea pigs, was isolated by Scott (1917) from house flies
(Musca domestica) caught in Washington, and he looks upon the fly
DISEASES BORNE BY NON-BITING FLIES 111
as the carrier of laboratory epidemics of rabbit and guinea pig septicemia
experienced for several years.
Bacillus diphtherie Klebs, the cause of DIPHTHERIA, according to
experiments performed by Graham-Smith (1910) may be taken up by flies
feeding on infected saliva or sputum and may live in the crop and intes-
tines of the fly for over 24 hours, and in fact in one experiment he twice
_recovered it from the feces of flies 51 hours after feeding on bacilli emulsi-
fied in broth.
Bacillus dysenterie “Y” Hiss and Russell, one of the organisms found
in DYSENTERY and INFANTILE DYSENTERIC DIARRHEA, was
experimented with by Tebbutt (1913) who fed it with blood to larve of
Musca domestica. The eggs from which these larvae were hatched were
washed in weak carbolic acid or lysol to disinfect them. Before feeding
the larve on the organism they were carefully washed in weak lysol
solution. In a limited number of cases the bacillus was recovered from
the pup and adults of larve thus fed.
The Shiga bacillus, Flexner bacillus and parabacillus of dysentery
were all isolated on flies in Macedonia and a decided correlation between
the incidence of flies and dysentery was established by Col. Dudgeon
(1919) and associates. They found the examination of fly feces the
most suitable method for the isolation of dysentery bacilli.
Bacillus enteritidis Gaertner, the cause of FOOD POISONING in
man, and epizootic diseases among animals, was experimented with by
Graham-Smith (1912), who fed it tothe larve of Calliphora erythro-
cephala and Musca domestica, but did not recover it in the adults matured
from these larve. Cox, Lewis and Glynn (1912) isolated a similar
bacillus from flies caught in Liverpool.
Bacillus fecalis alkaligenes Petruschky, a not infrequent inhabitant
of the human intestine, which has been associated with a case of severe
gastroenteritis, was isolated by Torrey (1912) from the intestinal con-
tent of city caught flies in two different instances.
Bacillus fluorescens liquefaciens Fluegge, a common organism found
in water and air, was fed by Cao (1906B) to larve of Musca domestica,
Calliphora vomitoria, Lucilia cesar, and Sarcophaga carnaria, on flesh
containing the organisms, and found among the predominant bacteria in
the feces of the larve. He found that this organism taken up by the
larve could persist through the pupal stage and be obtained from the
feces of flies immediately after their emergence, and when fed to adults
it was demonstrated on their eggs when deposited.
Bacillus fluorescens nonliquefaciens Eisenberg and Krueger, found in
water and in butter, was fed by Cao (1906B) to larve of Musca
domestica, Calliphora vomitoria, Lucilia cesar, and Sarcophaga carnaria,
and later demonstrated in the feces of the larve.
112 SANITARY ENTOMOLOGY
Bacillus gasoformans nonliquefaciens was found on the body and in
the alimentary canal of Musca domestica caught in London by Nicoll
(1911).
Bacillus griinthal was found on the body and in the intestines of
Musca domestica by Nicoll (1911).
Bacillus lactis acidi Marpmann, a zymogenic bacillus found in cows’
milk, was isolated by Torrey (1912) from the surface of city caught flies,
Bacillus lactis aérogenes Escherich, which is almost constantly found
in milk and is one of the chief causes of souring of milk, was isolated from
flies by Cox, Lewis and Glynn (1912).
Bacillus lepre Hanson, cause of LEPROSY, may be carried by Musca
domestica, according to Leboeuf (1913).
Bacillus mallet Loffler and Shutz may be transmitted by flies according
to Rosenau (1916).
Bacillus neapolitanus has been found on.the body of Musca domestica
by Nicoll (1911) and Cox, Lewis and Glynn (1912).
Bacillus oxytocus perniciosus Wyssokowitsch, a pathogenic organism
found in milk, has been isolated from the intestines of Musca domestica
by Nicoll (1911).
Bacillus paracoli Duval and Schorer, a pathogenic organism found
frequently in the stools of children suffering from summer diarrhea, has
been isolated several times by Torrey (1912) in New York, both from
the surface and intestines of city caught flies.
Bacillus paratyphosus “A”? Schottmiiller, cause of PARATYPHOID
A fever was isolated from the intestinal contents of city caught flies by
Torrey (1912).
Bacillus paratyphosus “B” Schottmiiller, cause of PARATYPHOID
B fever, was recovered from the body and intestines of Musca domestica
caught in London by Nicoll (1911), with the evidence that it had been
carried by the flies at least for 11 days.
Bacillus pestis Kitasato, the cause of BUBONIC PLAGUE, although
normally carried by fleas, has been shown by Yersin (1894) and Nuttall
(1897) capable of remaining in the intestines of flies in a virulent condi-
tion for at least 48 hours after infection. Nuttall’s experiments indicated
that this bacillus is fatal to Musca domestica. ;
Bacillus prodigiosus Ehrenberg, a nonpathogenic, zymogenic, and
chromogenic organism, was fed by Cao (1906B) to adult flies of Musca
domestica, Calliphora vomitoria, Lucilia cesar, and Sarcophaga carnaria
and was demonstrated in their feces and on their eggs 24 hours later.
Larve fed on polluted meat contained the germs in their bodies and
carried them through pupation and they could be demonstrated in the
intestines of the adult up to nine days after emergence. Ledingham
(1911) corroborated Cao’s findings of the persistance of this bacillus
DISEASES BORNE BY NON-BITING FLIES 113
throughout the metamorphosis of Musca domestica. Graham-Smith
(1913) found that flies of Musca domestica fed on this bacillus may infect
milk for several days, while Calliphora vomitoria flies when infected con-
stantly produced infection in milk up to the eighth day and in syrup up
to the twenty-ninth day.
Bacillus proteus vulgaris Hauser, B. p. mirabilis Hauser, and B. p.
zenkeri were fed by Cao (1906B) to larve of Musca domestica, Calliphora
vomitoria, Sarcophaga carnaria, and Lucilia cesar, and were found
abundantly in the feces of the larve so fed. Species of Proteus were also
found deposited with the eggs of flies fed on infected flesh. Bacillus
proteus vulgaris was isolated by Scott (1917) from Musca domestica
caught in Washington.
Bacillus pyocyaneus Gessard associated with SUPPURATING
WOUNDS in which blue-green pus is present was isolated in two strains
from flies caught in Liverpool by Cox, Lewis and Glynn (1912). Bacot
and Ledingham (1911) by carefully controlled experiments have proved
that the larve of Musca domestica fed on infected food retain this bacillus
in the gut through the metamorphosis to the adult stage and may dis-
tribute it in their excreta.
Bacillus radiciformis Tataroff, a saprophytic organism found in
water, was fed by Cao (1906B) to larve of Musca domestica, Calliphora
vomitoria, Lucilia cesar and Sarcophaga carnaria, and recovered from
the feces of the larve.
Bacillus ruber kielensis Breunig, a chromoparous (red) bacillus found
-in water at Kiel, was fed by Cao (1906B) to larve of Musca domestica,
Sarcophaga carnaria, Calliphora vomitoria, and Lucilia cesar, and he
demonstrated that the larve could take it up in all stages of growth, and
that the bacilli persisted in their bodies through pupation to maturity.
Bacillus schaffert Freudenreich, a nonpathogenic, zymogenic organism,
found in “puffy” and “Nissler’” cheese, has been found by Nicoll (1911) in
London on the body and in the intestines of Musca domestica.
Bacillus septicus agrigenus Nicolaier, a pathogenic organism, was fed
by Marpmann (1897) to flies, and 12 hours later the contents of the
flies were inoculated into mice, producing fatal infection in a large per
cent of the inoculations (Nuttall 1899).
Bacillus “similcarbonchio” Cao, a pathogenic organism similar to
Bacillus anthracis, which produces CARBUNCLES when inoculated, was
fed by Cao (1906B) to larve of Musca domestica, Calliphora vomitoria,
Lucilia cesar and Sarcophaga carnaria and isolated from the feces of
the larve in a very virulent strain. In examinations of many flies caught
in the laboratory he occasionally isolated a non-pathogenic, mobile strain
of this organism.
Bacillus subtilis Ehrenberg, an organism frequently found in air,
114 SANITARY ENTOMOLOGY
water, and soil, and seldom pathogenic, was fed by Cao (1906B) to larve
of Musca domestica, Calliphora vomitoria, Lucilia cesar and Sarcophaga
carnaria and was among the predominant bacteria recovered from the
feces of the larve.
Bacillus suipestifer Salmon and Smith, often found in cases of FOOD
POISONING and SUMMER DIARRHEA, is recorded by Scott (1917)
from the house fly, Musca domestica.
Bacillus ‘‘tifosimile” Cao, a pathogenic organism strongly resembling
B. typhosus, was fed by Cao (1906B) to larve of Musca domestica,
Calliphora vomitoria, Lucilia cesar, and Sarcophaga carnaria and later
demonstrated in the feces of the larve as among the predominant forms in
strains of differing virulence.. From flies caught around the laboratory
he isolated pathogenic strains adhering to the eggs when deposited.
Bacillus tuberculosis Koch, the cause of TUBERCULOSIS, was found
in four out of six flies caught by Hofmann (1888) in the room of a tuber-
culosis patient, whose sputum had contained many germs. Flies fed
artificially with sputum died in a few days. Within twenty-four hours of
their being fed on the sputum, the tubercle bacilli appeared in their
excreta. A guinea pig inoculated with the intestines of flies developed
tuberculosis. Celli (1888) reports Alessi’s experiments of inoculating
the feces of flies fed on tubercular sputum, and causing the development
of tuberculosis in two rabbits. Spillman and Haushalter (1887) were,
however, the first to find the tubercle bacilli in the intestines and feces of
flies which had fed on sputum.
Bacterium tularense McCoy and Chapin, cause of a fatal RODENT
PLAGUE of which a few human cases are on record, may be transmitted
by Musca domestica, Wayson (1915) inoculated the crushed bodies of
flies fed on the viscera of an animal dead 48 hours and obtained fatal
results in three series of experiments with guinea pigs.
Bacillus typhosus Eberth, the cause of TYPHOID FEVER, was
first shown by Celli (1888) to be capable of passing through the intestines
and into the feces of flies. Many authors have added proofs of the réle
of the fly in the transmission of this disease and these are ably summarized
by Graham-Smith (1913) and Hewitt (1914). Faichnie (1909) proved
that flies could carry this bacillus in their intestines for 16 days. Leding-
ham has isolated the bacillus from the intestines of Musca domestica which
had fed on it in the larval stage, but found that the normal bacilli in the
larval intestines usually prevent its successful survival through meta-
morphosis.
Bacillus vesiculosus, which is very frequently found in human excre-
ment, was found on the body of Musca domestica caught in London by
Nicoll (1911).
Bacillus xerosis Kutschert and Neisser, a presumably nonpathogenic
DISEASES BORNE BY NON-BITING FLIES 115-
organism, usually found in the eyes, and often associated with conjunc-
tivitis, was isolated by Torrey (1912) on the surface of city caught flies.
Thallophyta: Fungi: Schizomycetes: Spirillaceae
Spirillum (Vibrio) cholere Koch, the cause of ASIATIC CHOLERA,
may be carried by flies. The connection of flies with the prevalence of
cholera was first noted by Nicholas (1873). Maddox (1885) first per-
formed experiments with Calliphora vomitoria Linnaeus and Eristalis
tenaz Linnaeus as well as other insects and determined microscopically
the presence of the motile cholera vibrios in the feces. Tizzoni and
Cattoni (1886) caught flies in cholera wards and after several hours
obtained characteristic cultures of the organism. Many other authors, as
Sawtchenko (1892), .Simmonds (1892), Uffelmann (1892), Macrae
(1894), have furnished proofs of fly dissemination of the cholera vibrio, a
summary of which can be found in the books by Graham-Smith and
Hewitt.
SUMMARY OF PLANT ORGANISMS
A brief survey of the data presented above will perhaps help to imprint
the gravity of the fly menace on all who read this. Sixty-three minute
plant organisms have been shown to be transmissible by domestic flies.
Forty-four of these organisms have been found on or in flies caught in
cities or buildings, in other words, were naturally carried by so-called
“wild flies.” Among these forty-four organisms naturally carried by flies
were several normal inhabitants of milk, also various normal inhabitants
of the human and of animal intestines, which could only be taken up from
excrement. Some of these organisms are taken from eyes, some from
sputum, some from decaying vegetable matter, others from dairy products.
The fly containing such organisms betrays its habits. We find the
organisms of conjunctivitis, infantile diarrhea, sour milk, gas gangrene,
enteritis, guinea pig septicaemia, leprosy, paratyphoid A, and paraty-
phoid B fevers, bubonic plague, green pus, food poisoning, tuberculosis,
typhoid fever, anthrax, rodent plague, gonorrhea, abscesses, erysipelas,
bacillary dysentery, and cholera, and possibly cerebrospinal meningitis,
normally carried by flies which frequent our houses, visit our bodies and
pollute our food with their excreta. We also find experimental evidence
that these same flies can carry the organisms of diphtheria, gastroenter-
itis, and other pathogenic conditions.
In other words, it would seem that non-blood-sucking flies can carry
any bacterial or coccal disease in which the organism may be reached by
the fly on the body of the person, in his sputum, or his excreta, and
undoubtedly the same is true of such diseases of animals.
116 SANITARY ENTOMOLOGY
It is of interest to note that in nineteen species the organism has been
proven to pass freely through the intestinal canal of the larvae, in thirty-
seven species through the intestines of the adult, and in eleven species
to be capable of persisting in the larve through metamorphosis to the
adult. What greater argument could be found that flies are dangerous
not only because of what they as flies have fed on, but also because of
food they took while larve, possibly a long distance away?
We have not, however, gauged the depth of the fly’s infamy, as we have
so far only listed the evidence of plant diseases transmitted.
DISEASES OF UNSETTLED ORIGIN PROBABLY CAUSED BY
MICROORGANISMS
PURULENT OPHTHALMIA is said to be carried by flies in Egypt.
Brumpt accused Musca domestica of being a carrier of TRACHOMA.
Rosenau stated that flies have been found breeding in open lesions of
SMALLPOX, and that flies may transmit MEASLES and SCARLET
FEVER. Definite experiments certainly should be carried out with a
view to determining the exact relationship of flies to these diseases, seek-
ing first the possibility of transmission by fecal contamination.
Howard and Clark (1912) found that Musca domestica flies can
retain the virus of INFANTILE PARALYSIS or POLIOMYELITIS
either in or on their bodies for 24 and 48 hours. The virus may remain
alive in the body of the fly six hours after ingestion. The fly can obtain
the virus from secretions of nose and throat and discharge of intestines.
Very recently Dorset (1919) and associates have experimentally
transmitted HOG CHOLERA by inoculating with crushed bodies of
infected Musca domestica and Fannia canicularis, and also by bringing
such flies in contact with abraded surfaces.
ANIMAL ORGANISMS CARRIED BY NON-BITING FLIES
We will now consider in a similar manner the evidence of transmission
of animal organisms by these same flies.
Protozoa
Sarcodina: Amoebina: Amoebidae
Léschia coli (Lésch) (Endamoeba) a supposedly harmless commensal
in the alimentary canal of man, where it feeds on the contents of the.
bowels, may be carried in the encysted form by Musca domestica, accord-
DISEASES BORNE BY NON-BITING FLIES 117
ing to Roubaud (1918), who finds that the cysts readily pass through the
fly intestines at laboratory temperatures of 15-18° C. (59-65° F.) in 24
hours. It may be carried from iufected stools to food but must be
deposited in moist substances, as all cysts dry rapidly in dry fly
feces.
Léschia histolytica (Schaudinn), the cause of AMOEBIC DYSEN-
TERY, may be carried in the encysted form by Musca domestica and
Calliphora erythrocephela according to Flu (1916). Roubaud (1918)
has carefully investigated and finds that the free amoeba is quickly
digested by the fly, but the cysts may pass readily through the intestines
within 24 hours and may be demonstrated up to 40 hours. The cysts die
rapidly in dry fly feces, and therefore to live must be placed on moist
substances, or on food.
Mastigophora: Protomonadina: Bodonidae
Prowazekia sp. is found in Fannia canicularis (Dunkerly 1912).
Mastigophora: Polymastigina: Polymastigidae
Giardia intestinalis (Lambl) (Lamblia), the cause of LAMBLIAN
DYSENTERY of rodents and man, may be carried in the encysted form
by Musca domestica, according to Roubaud (1918), but must be deposited
in the feces on moist substances, or directly on food.
Mastigophora: Binucleata: Leptomonidae
Crithidia calliphorae Swellengrebel is described as a parasite of
Calliphora erythrocephala Meigen..
Crithidia muscae-domesticae Werner is described as a parasite of
Musca domestica Linnaeus.
Leptomonas calliphorae (Swingle) is a parasite of Calliphora erythro-
cephala Meigen.
Leptomonas drosophilag Chatton and Alilaire is a parasite of
Drosophila confusa.
Leptomonas homalomyiae (Brug) is a parasite of Fannia scalaris
Fabricius.
Leptomonas lineata (Swingle) is a parasite of Sarcophaga sarraceniae
Riley.
Leptomonas luciliae (Strickland) is a parasite of Lucilia sp.
Leptomonas luciliae (Roubaud) is described as a parasite of Lucilia
serenissima Walker.
Leptomonas mesnili Roubaud is a parasite of Lucilia sp.
118 SANITARY ENTOMOLOGY
Leptomonas muscae-domesticae (Burnett) is a parasite of Musca
domestica Linnaeus, M. nebulo Fabricius, Fannia scalaris Fabricius,
Pollenia rudis Robineau-Desvoidy, Teichomyza fusca Macquart, Lucilia
sp., Pycnosoma putorium Wiedemann, Scatophaga lutaria Fabricius,
Neuroctena anilis Fallen, Homalomyia corvina Verrall, and Sarcophaga
murus, undergoing complete metamorphosis in the bodies of the flies.
Patton (1910) has demonstrated that the disease may be transmitted
from fly to fly as follows: the food becomes infected from the feces of
the infected flies which have fed on it; uninfected flies may become in-
fected by ingesting either the long flagellates, the short encysting forms,
or the cysts, in the feces of other flies, or in food contaminated by other
flies.
Leptomonas pycnosomae Roubaud is a parasite of Pycnosoma
putorium.
Leptomonas roubaudi Chatton is a parasite in the Malpighian glands
of Drosophila confusa Staeger.
Leptomonas sarcophagae (Prowazek) is a parasite in the gut of
Sarcophaga haemorrhoidalis Fuller and another species of Sarcoph-
aga.
Leptomonas soudanensis Roubaud is a parasite of Pycnosoma
putorium.
Leptomonas stratiomyiae (Fantham and Porter) is a parasite of
Stratiomyia chameleon Linnaeus and S. potamida Meigen. Fantham and
Porter (1916) proved it experimentally pathogenic by inoculation to
Mus musculus.
Leishmania tropica (Wright), the cause of ORIENTAL SORE of
man, may be taken up in the crithidial stage by Musca domestica and
the organism demonstrated 48 hours after feeding, according to Carter
(1909). According to Wenyon (1911) who investigated BAGDAD
SORE, Musca domestica may readily feed on the sores and take up
Leishmania, but there is no development of the organism and no parasites
were found in the feces. On the other hand, Row, working with CAMBAY
SORE believed the organism transmissible by Musca domestica up to
three hours after the fly had fed on infected sores. He found the gut con-
tents of flies infective for a monkey three hours after the fly had taken up
Leishmania, but Patton (1912) maintains that Cambay sore never com-
mences in a cut, scratch or abrasion, and failed to transmit the disease
in this manner in numerous experiments with Musca nebulo and Musca sp.
A new investigation, however, is warranted by Row’s statement, seeking
fecal infection of wounds.
Rhynchoidomonas luciliae Patton is parasitic in the Malpighian
tubules of Musca nebulo and Lucilia serenissima.
DISEASES BORNE BY NON-BITING FLIES 119
Mastigophora: Binucleata: Trypanosomidae
Castellanella evansi (Steel) Chalmers (Trypanosoma) 2, the cause of
SURRA, an African disease of horses and other mammals, may be carried
by Musca domestica by contact with wounds.
Castellanella hippicum (Darling) Chalmers (Trypanosoma),” the
cause of MURRINA, a disease of horses and mules in the United States
and Panama, may be carried according to Darling (1911, 1912) by Musca
domestica, Chrysomya and Sarcophaga, from wounds by mechanical
transmission. He ascertained that the trypanosomes remained alive in
the proboscis of the fly at least two hours, and he also successfully inocu-
lated a mouse with the crushed portions of a proboscis of a fly which had
fed on infected blood. Isolation of the animals from fly attack, and bind-
ing up of wounds wiped out the epidemic. He did not ascertain whether
the trypanosome might pass out of the fly’s feces and contaminate lesions
in this manner, which naturally is the normal method of fly transmission.
Mastigophora: Spirochaetacea: Spirochaetidae
Treponema pertenue (Castellani), the cause of YAWS, an infectious
disease of men, may be transmitted by the house fly, Musca domestica.
Castellani in Ceylon (1907) found that flies eagerly crowd around the
open sores of yaws patients. In the hospitals as soon as the dressings
were removed from the yaws ulcerations, they became covered with flies,
sucking with avidity the secretion, which they may afterward deposit in
the same way on ordinary ulcers on other people. He conducted experi-
ments which proved that the flies do take up the organism, which he recov-
ered from the dissected mouth parts. He fed flies on the organism, then
removed their appendages and fastened them over scarified areas of skin
of monkeys, and obtained in two experiments positive lesions by this
organism. Robertson (1908) also definitely obtained this spirochaete
from flies collected on yaws lesions. Nicholls (1912) ascribes most of the
cases of yaws in the West Indies to inoculation of surface injuries by
Oscinis pallipes Loew. Sarcophaga is also considered a carrier. None
of the experiments have been directed at obtaining infection through the
deposition of the spirochaetes, taken up by the fly in feeding, in its feces
on other ulcers or injuries. This would appear to be the most likely
method of infection.
*The classification of the Trypanosomes has recently been modified by Chalmers,
including several genera composed of species with similar morphological and_ bio-
logical characteristics.
120 SANITARY ENTOMOLOGY
Neosporidia: Myxosporidia: Nosemide
Nosema apis Zander, a bee disease, may be communicated to Calliphora
vomitoria and other insects through feeding on the bee excreta around
beehives.
Protozoa: Neosporidia: Myxosporidia: Thelohanidae
Octosporea monospora Chatton and Krempf is a parasite of Fannia
scalaris.
Thelohania ovata Dunkerly is also a parasite of Fannia scalaris.
HIGHER ORGANISMS CARRIED BY FLIES
As pointed out in the introduction of this lecture, flies can carry the
eggs of higher organisms. The evidence is presented below, but refer-
ence should be made to Dr. Ransom’s lecture (Chapter V).
Platyhelmia: Cestoidea: Cyclophyllidea: Taeniidae
Taenia (Taeniarhynchus) saginata Goeze, the FAT-TAPEWORM
of cattle and rarely of man, has been commonly found in the egg stage in
Musca domestica in British East Africa according to Shircore (1916).
It is necessary that the eggs, passed in human or animal feces, reach the .
food or water of the next host (cattle). This may occur by means of
insanitary sewage disposal, possibly under exceptional circumstances by
the agency of flies.
Platyhelmia: Cestoidea: Cyclophyllidea: Hymenolepididae
Choanotaenia infundibulum (Bloch) Cohn, the FOWL TAPEWORM,
developed to the cysticercoid stage in Musca domestica fed on the eggs,
and Guberlet (1916) succeeded in infecting new-born chicks by feeding
them on infected Musca domestica.
Davamea cesticillus Molin, a fowl tapeworm, was tested with negative
results by Guberlet (1916), using Musca domestica and Calliphora vomi-
toria in his search for the intermediate host.
Davainea tetragona Molin, another chicken tapeworm, likewise gave
Guberlet (1916) negative results with the same two species of flies.
Platyhelmia: Trematoda: Malacotylea: Schistosomidae
Schistosoma mansoni Sambon, the trematode worm causing intestinal
Schistomiasis of man or BILHARZIOSIS, may be found in the egg stage
DISEASES BORNE BY NON-BITING FLIES 121
in Musca domestica, according to Shircore (1916), who-recorded eggs of
this species in flies in British East Africa. The cercaria stage is passed
in a snail.
Nemathelminthes: Nematoda: Spiruridae
Habronema muscae (Carter) Diesing, a STOMACH WORM OF
HORSES, passes its earlier stages in Musca domestica, according to Ran-
som (1913). Ejither the egg or first-stage larva is ingested by the fly
larva breeding in horse manure. Development goes on within the fly
larva and pupa, the last stage being found in the proboscis of the adult
fly. It passes to horses through the swallowing of infested flies and
probably may also leave the proboscis of the fly while the insect is feeding
on the mucous membranes of the horse.
Van Saceghem (1917, 1918) placed flies bred from larve fed on
infected manure, on skin lesions of a horse and produced infections of
EQUINE GRANULAR DERMATITIS, caused by the presence . of
Habronema larve in the skin.
Habronema microstoma (Schneider) Ransom and H. megastoma
(Rudolphi) Seurat have also been shown to pass their developmental
stages in Musca domestica. (See Chapter V.)
Nemathelminthes: Nematoda: Ascaridae
Ascaris lumbricoides Linnaeus, the cause of HUMAN ASCARIASIS,
does not require an intermediate host. Stiles in 1889 fed Musca domestica
larve on female Ascaris and later found the eggs in different stages of
development in both larve and adult flies (Graham-Smith, 1913). Shir-
core (1916) in British East Africa found the eggs in the intestines of
Musca domestica in nature. Nicholls (1912) in St. Lucia found the
eggs in the abdomens of flies, Borborus punctipennis Macquart (Limo-
sina), taken at fecal matter. (See Chapter V.)
Nemathelminthes: Nematoda: Oxyuridae
Oxyuris Curvula Rudolphi, the EQUINE PINWORM, is recorded
by Patton and Cragg (1913), as probably the species of Oxyuris, which
in Madras is often found in the embryo stage heavily infesting the larve
of Musca nebulo.
Oxyuris vermicularis Linnaeus, the HUMAN PINWORM, can be
ingested in the egg stage by flies, according to Grassi (1883).
122 SANITARY ENTOMOLOGY
Nemathelminthes: Nematoda: Ancylostomidae
Ancylostoma duodenale Dubini, cause of HOOK WORM disease of
man, has been found in the egg stage in house flies, Musca domestica, by
Shircore (1916) in British East Africa, and it is therefore possible that
the eggs may be placed on food, in which the hook worm larva could
hatch and be directly conveyed into the body with the food. No develop-
ment takes place in the flies.
Necator americanus Stiles, the American HOOK WORM, was collected
in the egg stage in the intestines, of Limosina punctipennis in St. Lucia
by Nicholls (1912). Galli-Valerio (1905) found that flies could carry
on the surface of their bodies not only the eggs but also the larve
of this worm.
Nemathelminthes: Nematoda: Trichosomidae
Trichiuris trichiura (Linnaeus), the WHIP WORM of man, was col-
lected in the egg stage by Shircore (1916) in British East Africa in the
abdomen of Musca domestica and by Nicholls (1912) in St. Lucia in the
abdomen of Borborus punctipennis (Limosina), and the latter succeeded
in feeding Musca domestica on the eggs. It probably does not require
the flies as immediate hosts, but is undoubtedly distributed in this manner.
Thus to the already long list of serious diseases in whose spread the
non-blood-sucking flies may play some part we may now add hog cholera,
poliomyelitis, amoebic dysentery, Lamblian dysentery, Oriental sore,
surra, murrina, yaws, purulent ophthalmia, trachoma, the fat-tapeworm
of cattle, the fowl tapeworm, bilharziosis of man, the stomach worm
of horses, equine granular dermatitis, human ascariasis (not normal
method), equine pinworm, pin itch, two hook worms, and the whip worm,
and possibly also smallpox, measles and scarlet fever.
We found that the bacteria were only mechanically carried by the
flies, except in the case of Bacillus anthracis. Among the protozoa also
those organisms parasitic in vertebrates all seem to be mechanically
transmitted. The various parasites mentioned, however, pass complete
life cycles in the body of the fly. Among the worms, however, there are
cases of external mechanical carriage, transmission of eggs through
the intestinal canal, retention of the egg from larva to adult fly (Ascaris
lumbricoides), and also cases of the fly serving as an intermediate host
(Choanotaenia infundibulum, and Habronema spp.). The last named
worms are the only organisms known to be transmitted by the fly which
work forward into the proboscis for transmission at time of feeding.
A bibliography of the works cited in the lecture follows:
DISEASES BORNE BY NON-BITING FLIES 123
IMPORTANT GENERAL TEXTBOOKS
Fantham, H. B., Stephens, J. W. W., and Theobald, F. V., 1916.—The
Animal Parasites of Man. Wm. Wood & Co., New York, 900 pp.
Graham-Smith, G. S., 1913.—Flies in Relation to Disease. Non-Blood-
Sucking Flies. Cambridge Univ. Press, 292 pp.
Herms, Wm. B., 1915.—Medical and Veterinary Entomology. The Mac-
millan Company, New York. .
Hewitt, C. Gordon, 1914.—The House Fly, Musca domestica Linn. Its
Structure, Habits, Development, Relation to Disease and Control.
Cambridge Univ. Press, 382 pp.
Hindle, Edward, 1914.—Flies in Relation to Disease. Blood-Sucking
Flies. Cambridge Univ. Press, 398 pp.
Patton, Walter Scott, and Cragg, Francis William, 1913.—A Textbook
of Medical Entomology. Christian Literature Society for India, Lon-
don, Madras and Calcutta, 764 pp. .
Riley, W. A., and Johannsen, O. A., 1915.—Handbook of Medical
Entomology. Comstock Publishing Company, Ithaca, N. Y.
SPECIAL REFERENCES
Cao, G., 1898.—L’Ufficiale San. Riv. D’Igiene di Med. Patr., vol. 11, pp.
331-348, 385-397.
Cao, G., 1906A.—Annali D’Igiene Sper., vol. 16, n. s., pp. 339-368.
Cao, G., 1906B.—Annali D’Igiene Sper., vol. 16, n. s., pp. 645-664.
Carter, R. M., 1909.—Brit. Med. Journ., vol. 2, pp. 647-650.
Castellani, A., 1907.—Journ. Hygiene, vol. 7, p. 567.
Castellani, A., and Chalmers, A. J., 1913.—Manual of Tropical Medi-
cine, 2nd edit., p. 700.
Celli, A., 1888.—Bullet. d..Soc. Lancisiana d. Ospedali di Roma, fasc. 1,
st.
a G. L., Lewis, F. C., and Glynn, E. E., 1912.—Journ. Hygiene.
vol. 12, No. 3, pp. 306-309.
Darling, S. T.,.1911.—Journ. Infect. Diseases, vol. 8, No. 4, pp. 467-
485. .
Darling, S. T., 1911.—Parasitology, vol. 4, No. 2, pp. 83-86.
Darling, S. T., 1912.—Journ. Exper. Med., vol. 15, No. 4, pp. 365-
366.
Darling, S. T., 1912.—Trans. 15th Internat. Congress Hyg. and Demog.,
Washington.
Davaine, C., 1870.—Bullet. de l’Acad. de Méd., Paris, vol. 35, pp. 471-
498.
124 SANITARY ENTOMOLOGY
Dorset, M., McBryde, C. N., Nile, W. B., and Rietz, I. H., 1919.—Amer.
Journ. Vet. Med., vol. 14, No. 2, pp. 55-60.
Dudgeon, L. S., 1919.—Brit. Med. Journ., No. 3041, April 12, pp. 448-
451.
Dunkerly, J. S., 1912.—Central. f, Bakt., Paras, und Infekt., vol. 62,
p. 138. .
Faichnie, N., 1909.—Journ. Royal Army Med. Corps, vol. 13, pp. 580-
584, 672-675.
Fantham, H. B., and Porter, A., 1916.—Journ. Parasit., vol. 2, No. 4,
pp. 149-166.
Flu, P. C., 1916.—Geneesk. Tijdschr. v. Nederl.-Indie, vol. 56, No. 6,
pp. 928-939.
Galli-Valerio, B., 1905.—Centralbl. f. Bakt. Orig., vol. 39, p. 242.
Graham-Smith, G. S., 1910.—Repts. Local Govt. Bd., on Public Health
and Medical Subjects, n. s., No. 40, pp. 1-40.
Graham-Smith, G. S., 1912.—Forty-first Ann. Rept. Local Govt. Bd.
1911-12, Suppl. Rept. Medic. Off., pp. 304-329, 330-335.
Grassi, B., 1883.—Arch. Ital. de Biol., vol. 4, pp. 205-208.
Guberlet, J. E., 1916.—Journ. Am. Vet. Med. Assn., vol. 49, pp. 218-
237.
Hofmann, E., 1888.—Correspondenzbl. d. arztl. Kreis- und Bezirks-
vereine im Kénigr. Sachsen, vol. 44, No. 12, pp. 130-133.
Howard, C. W., and Clark, P. F., 1912.—Journ. Exper. Med., vol. 16,
No. 6, pp. 850-859.
Leboeuf, A., 1913.—Bull. Soc. Path. Exot., vol. 6, No. 8, pp. 551-556.
Ledingham, J. C. G., 1911.—Journ. Hygiene, vol. 11, No. 3, pp. 333-
340.
MacGregor, M. E., 1917.—Journ. Trop. Med. and Hygiene, vol. 20. No.
18, p. 207.
Macrae, R., 1894.—Indian Med. Gazette, pp. 407-412.
Maddox, R. L., 1885.—Journ. Roy. Microsc, Soc., Ser. 2, vol. 5, pp. 602-
607, 941-952.
Marpmann, G., 1897.—Centralbl. f. Bakteriol., 1 Abt., vol. 22, pp. 127-
182.
Morgan, H. deR., and Ledingham, J. C. G., 1909.—Proc. Roy. Soc.
Med., vol. 2, pt. 2, pp. 133-149.
Nicholas, G. E., 1873.—Lancet, vol. 2, p. 724.
Nicoll, W., 1911.—Journ. Hygiene, vol. 11, No. 3, pp. 381-389.
Nicholls, L., 1912.—Bull. Ent. Research, vol. 3, No. 1, p. 85.
Nuttall, G. H. F., 1897.—Centralbl. f. Bakteriol., vol. 22, pp. 87-97.
Nuttall, G. H. F., 1899.—Johns Hopkins Hospital Reports, vol. 8, Nos.
1-2, pp. 1-154.
Patton, W. S., 1910.—Bull. Soc. Path. Exot., vol. 3, pp. 264-274.
DISEASES BORNE BY NON-BITING FLIES 125
Patton, W. S., 1912.—Sci. Mem. Officers Med. & Sanit. Dept., Govt.
India, No. 50, 21 pp.
Ransom, B. H., 1913.—U. 8S. Dept. Agr., Bur. Anim. Ind., bull. 163,
pp. 1-36.
Robertson, A., 1908.—Journ. Trop. Med. and Hygiene, vol. 11, p.
213.
Rosenau, M. J., 1916.—Preventive Medicine and Hygiene, pp. 206-252.
Roubaud, E., 1918.—Bull. Soc.’ Path. Exot., vol. 11, No. 3, pp. 166-
171.
Sawtchenko, J. G., 1892.—Review in Ann, Inst. Pasteur, vol. 7.
Scott, J. R., 1917.—Journ. Med. Research, vol. 37, No. 164, pp. 115,
121-124,
Shircore, J. O., 1916.—Parasitology, vol. 8, No. 3, pp. 239-243
Simmonds, M., 1892.—Deutsch. med. Wochenschr., No. 41, p. 931.
Spillman and Haushalter, 1887.—Compt. Rend. Acad. Sci., vol. 105, pp.
352-353.
Tebbutt, H., 1913.—Journ. Hygiene, vol. 12, pp. 516-526.
Tizzoni, G., and Cattani, J., 1886.—Centralbl. f. d. med. Wissensch.,
Berlin, pp. 769-771.
Torrey, J. C., 1912.—Journ. Infect. Diseases, vol. 10, No. 2, pp. 169-
176.
Uffelmann, J., 1892.—Berliner klin. Wochenschr., pp. 1213-1214.
Van Saceghem, R., 1917.—Bull. Soc. Path. Exot., vol. 10, p. 726; 1918,
vol. 11, p. 575.
Wayson, N. E., 1915.—U. S. Public Health Service, Pub. Health Repts.,
vol. 29, No. 51, pp. 3890-3393.
Welander, 1896.—Wien. klin. Wochenschr., No. 52.
Wenyon, C. M., 1911.—Kala Azar Bull. vol. 1, No. 1, pp. 36-58,
Yersin, A., 1894.—Ann. Inst. Pasteur, vol. 8, pp. 662-667.
CHAPTER VIII
Important Phases in the Life History of the Non-Biting Flies *
W. Dwight Pierce
In the preceding lecture there was brought together an accumulation
of evidence against the common flies that frequent our houses which
should convince any one of the absolute necessity of: keeping flies from
our food, our houses and our bodies. We can only hope to accomplish
this object by becoming familiar at least with the more important features
in the life history of the flies. From the study of the transmission of
diseases we may pick out for example a few points in the biology which
need to be stressed, such as feeding habits, regurgitation of food, excreta,
breeding places, oviposition, flight, attraction to odor:
We are dealing in this lecture not only with the common house fly
but also with most of the common flies which frequent our houses and are
known as domestic flies. Of the common household flies, only one, the bit-
ing stable fly, Stomoxys calcitrans, is omitted for future discussion.
Students would do well to examine some book in which the different
species are illustrated, so as to become familiar with the characteristic
markings. It will then be a good plan to collect the various flies around
the house and determine their species.
Fairly good illustrations of common household flies. are given by
Howard and Hutchinson (1915), and Richardson (1917).
The best illustrations of the flies are contained in Patton and Cragg’s
textbook (1913).
Tables to species of common flies and also illustrations are presented
by Riley and Johannsen (1915).
It is also desirable to know how to identify the fly larvae when found.
The best American work on this subject is by Banks (1912). See also
Riley and Johannsen, p. 315.
For general information on the life history, morphology, and anatomy
of the house fly refer to Hewitt (1917).
The flies are classified largely on the characters of the proboscis,
antenne, wing veins, eyes and the arrangement of hairs. The larve are
classified on the characters of the spiracles, the cephalo-pharyngeal
skeleton, tubercles, hairs and processes.
+This lecture was read July 22 and distributed July 29, 1918.
126
PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 127
HOUSE FLY, MUSCA DOMESTICA LINNAEUS 2
(See Frontispiece )
The common house fly, Musca domestica, is that insect charged with
_the carriage of the greatest number of diseases, and probably justly, be-
cause of its frequentation of all types of excreta, garbage and waste,
its common visitations to places where foods are handled, and also its
visits to the human body. We have shown in the preceding lecture how
it and its allies can carry disease and what diseases are charged against
each. Now we will take a brief review of its life history in order to
arrive at important data for handling its control.
The house fly adult is yellowish to dark gray in color, with four
equally broad longitudinal stripes on the thorax; first three abdominal
segments yellowish with a central black stripe and with two less distinct
discal stripes. The males measure 5.8 to 6.5 mm. in length, and_ the
females 6.5 to 7.5 mm. The eyes in the male are nearly contiguous and
in the female are widely separated.
This fly has been distributed by commerce to almost all parts of the
civilized world.
Certain features of its anatomy are of interest in the present study.
The head is prolonged to form a proboscis which is enlarged at tip
into the haustellum bearing apically the oral lobes or labella. These lobes
bear a large number of channels kept open by incomplete chitinous rings
called pseudotracheae, which are fully described by Graham-Smith (1913).
The proboscis of the house fly is adapted to sucking and the absorption
of liquid or liquefied food. It cannot take up very large particles of solid
food. Nicoll (1911) found that the flies could not ingest particles larger
than .045 mm. This therefore determines the size of worm eggs which
can be ingested by the adult. We must assume therefore that when
flies contain larger eggs, these were taken in by the larva. Normally,
however, the food must pass between the bifid extremities of the chitinous
rings of the pseudotracheal channels and pass along these to the mouth.
These openings measure from .003 to .004 mm. in diameter. Solid par-
ticles, however, are heaped up in a slight ridge in the channel between the
oral lobes and are probably sucked into the oral pit and into the
mouth.
When the fly feeds on dry substances such as sugar, dried specks of
milk, or sputum, etc., it first liquefies the substance by a salivary secre-
tion which flows into the oral pit and onto the substance, being dis-
tributed by the pseudotracheal channels. The moistening is also aided
» An appeal has been made to the International Commission for Zoological Nomen-
clature for the retention of Musca in this sense with domestica as type.
128 SANITARY ENTOMOLOGY
by the regurgitation of food from the crop, as proven by Graham-Smith,
who fed flies upon carmine colored food, and found carmine stains on
semi-fluid material upon which these flies later fed, for 22 hours.
The intestinal canal is composed of pharynx, esophagus, crop, pro-
ventriculus, ventriculus or chyle stomach, proximal and distal intestine
and rectum. The esophagus passes from the pharynx through the cer-
vical region into the thorax, in the anterior part of which it opens into
the proventriculus, and from this same point a duct which is continuous
with the esophagus passes back into the abdomen to the crop which is a
bilobed sac, capable of considerable distention. This crop serves as a
food reservoir. The fly feeds until it has engorged the crop, and often
will continue feeding, the food then passing directly into the proventri-
culus. The opening of the proventriculus into the esophagus is ventral.
This organ is circular, flattened dorsoventrally. The ventriculus is
tubular, narrowest in front and narrowing again in passing through the
thoraco-abdominal foramen. The proximal intestine is the longest region
of the gut, being considerably coiled. The distal intestine begins at the
entrance of the Malpighian tubules, and is only curved once. It is sep-
arated from the rectum by a valve. The rectum is composed of three
parts, the intermediate of which is swollen to form the rectal cavity into
which the four rectal glands empty.
Food may remain in the crop for several days, and even when no
further food is given, it requires many hours to empty the crop com-
pletely. After feeding the fly usually retires to a quiet spot and cleans
its head and proboscis. It frequently regurgitates its food from the crop
in the form of large drops of liquid which are subsequently slowly drawn
up again and probably pass into the proventriculus. These drops of
regurgitated food frequently are deposited, often for the purpose of
moistening sugar and similar dry foods.
We may now see how easy it is for a fly which has fed on infected
substances to contaminate other substances for days by regurgitation
from the crop, as well as through fecal deposits. Experimental evidence
has proven contamination by both the feces and the vomit.
The fly’s body is externally constructed so as to further aid in
disease carriage. There are numerous hairs or sete on the body, espe-
cially on the legs. The last joint of the tarsus of each leg bears two
claws and a pair of membranous pyriform pads or pulvilli. These pulvilli
are covered beneath with innumerable, closely set, secreting hairs by means
of which the fly is able to walk in any position on highly polished sur-
faces. These sucker-like pads or pulvilli and the sete of the legs are
excellent bacteria carriers, and not infrequently larger organisms as
mites, worm eggs, etc., are thus carried.
The sexes of the house fly are about equal in number. Copulation
PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 129
may take place, according to Hutchison (1916), as early as the day
following emergence. Oviposition may begin on the third day.
He cites a large series of observations on the preoviposition period
showing that eggs may be laid from 21% to 23 days after emergence, and
that the period corresponds to temperature and humidity changes. At
Washington the shortest period was obtained at 82° to 84° F., and in
general the length of period increased with the decrease of temperature.
Increase in humidity seems to hasten egg laying.
The eggs are white, cylindrically oval, slightly broader at the pos-
terior end with two distinct curved rib-like thickenings on the dorsal
surface, along one of which the egg splits on hatching. These eggs
are laid in masses averaging about 120, and a female may lay as many
as four such batches, and probably under favorable conditions more. The
eggs usually hatch in less than 24 hours, the time of course depending
upon the climatic conditions. At 10° C. (40° F.) the egg period is two
or three days; at 15 to 20° C. (59-68° F.) it is 24 hours; at 25-35° C.
(77-95° F.) only 8 to 12 hours, according to Hewitt (1917).
The larve are white, smooth, cylindrical maggots, tapering at the head
end and considerably enlarged at the tail end. When viewed by trans-
mitted light a dark chitinous structure can be seen in the anterior
regions. This is called the cephalopharyngeal skeleton and is partially
extrusible. Each species of fly larva is distinguished by the form of this
skeleton and hence if a slide mount is made of a skin boiled in potash, the
species can be identified by this and one or more other characters. The
three larval stages differ somewhat in the form of this skeleton so that it
becomes possible to determine exactly the stage of development. The
body is composed of fourteen segments of which the second is the pro-
thorax. This segment at its posterior margin bears the anterior spiracles
which are fan-shaped and have six or seven lobes. This segment is fol-
lowed by the mesothorax, metathorax, and eight abdominal segments.
The ninth and tenth (anal) segments are small and ventral. The
anterior portion of the venter of each of the first eight abdominal
segments bears spiniferous pads which assist in locomotion. The eighth
or last apparent segment bears the spiracular plates. These spiracular
plates afford the best means of identification of fly larvae. In the first
two stages each plate consists merely of two oblique slits on a slight
prominence. In the third stage they are well defined plates, D-shaped,
closer together than their width, with flat faces opposed, each with three
sinuous slits.
In connection with this larval description, we may call attention to
errors existing in many larval descriptions. The thoracic spiracles belong
to mesothorax but often appear to have migrated to the prothorax. The
large terminal spiracles of Dipterous larve are always on the eighth
130 SANITARY ENTOMOLOGY
segment, as in almost all orders of insects. The ninth and tenth seg-
ments are apt to be small and obscure and center around the anus, which
belongs to the tenth.
The larval period varies in response to climatic stimuli, but under
favorable conditions is about four days in length. When full grown the
larva varies from 10 to 12 mm. in length. Pupation takes place within
the last larval skin which shrinks and hardens to form a reddish case or
puparium. This period lasts from 3 to 10 days. When the fly is ready
to emerge it pushes off the cap or head end. The entire developmental
period may require from eight to eighteen or more days. Kisliuk has
found pupae of the fly in manure piles at various times during the win-
ter, which of course indicates that the developmental period may occupy
an entire winter if the pupa is caught by cold weather. Bishopp, Dove
and Parman found that adults emerged from immature stages which had
been in manure for six months. Hutchison’s observations at Washington,
D. C., confirm these findings.
The adult flies are capable of considerable flight. Parker demon-
strated a migration of two miles in his Montana studies. Bishopp and
Laake (1919) record the flight of marked house flies of thirteen miles.
In this connection the most interesting contribution is that of Ball
(1918) in which he shows that house flies apparently migrated with the
wind from 46 to 95 miles from mainland to a tiny island.
The house fly has been found breeding in horse manure, human excre-
ment, and hog manure very freely and to some extent in cow and chicken
manure. It lays its eggs in a great variety of decaying animal and
vegetable materials, such as slops, spent hops, moist bran, ensilage,
rotting potatoes, dead animals, excreta-soiled straw, paunch contents of
slaughtered animals, soiled paper and rags, etc.
THE BLUE BOTTLE FLIES OF THE GENUS CALLIPHORA 3
The large blue bottle fly, Calliphora vomitoria Linnaeus (plate I,
fig. 1) and its near relative C. erythrocephala Meigen are often found in
houses. These flies have also been shown to be dangerous insects because
of their ability to transmit disease. In fact they are much more likely
to directly transmit disease organisms than the house fly because of
their habits of breeding in flesh which gives them also the name blow flies.
The adults are grayish on the thorax and dark metallic blue with sug-
gestions of silver on the abdomen. In vomitoria the gene are black and
beset with golden red hairs, while in erythrocephala the gene are fulvous
to golden yellow and beset with black hairs.
3 An appeal has been made to the International Commission for Zoological Nomen-
clature for the retention of Calliphora in this sense with vomitoria as type.
PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 131
These flies are necrophagous and deposit their eggs upon any fresh,
decaying or cooked meat, and upon dead insects; they breed occasionally
in human excrement and sometimes will deposit their eggs in open flesh
wounds. On the battle fronts of Europe and Asia where the wounded lay
for long periods and where many dead bodies remained uncared for, these
flies multiplied to tremendous numbers and were largely responsible for
the carrying of infections to wounds. When a fly lays its eggs in living
flesh and the larve develop therein, the infection is called myiasis. This
subject is of such importance that two entire lectures is devoted to it
(Chapters XII and XIII).
Important as they are, the blow flies are usually subordinated to
the house fly in the discussion of dangerous flies, but thorough investi-
gations of these species are more than likely to greatly increase their
standing as disease carriers.
The eggs are deposited in masses of as many as 300 and a single
fly may possibly deposit three batches. They hatch in from 10 to 24
hours after deposition.
The larve of C. erythrocephala may be distinguished from the house
fly larve by having usually nine but sometimes up to twelve lobes in the
anterior (thoracic) spiracles; an anterior scabrous swollen ring on each
of the first eight segments of the abdomen, and a ventral groove on
each segment beneath; the stigmal field concave, surrounded by three
pair of tubercles above, and two large and one small pair below; the
stigmal plates about once and a fourth their diameter apart, each with
three straight slits, directed principally toward the opposite plate; and
also, by having an anal pair of tubercles. The larval characters are
illustrated by Hewitt and also by Banks.
The larval period requires seven and a half to eight days at 23° C.
(73.5° F.) and the pupal period fourteen days, according to Hewitt.
Bishopp and Laake found the larve to attain full growth in three to four
days and the time from deposition of eggs to emergence of adults was 15
to 20 days.
THE SHEEP MAGGOTS OR GREEN BOTTLE FLIES
The European sheep maggot fly, Lucilia sericata Meigen, is primarily
an outdoor fly but occasionally is found indoors, especially in farm and
country houses. It ‘is more brilliant than the Calliphoras, being of a
burnished gold with a shining, bluish-green color. The flies are strongly
attracted to meat and carcasses in which they lay their eggs. They
also occur on human and animal excrement. The larve breed readily
in all these substances. In Europe the flies very commonly lay their
eggs in matted wool and on the flesh on the backs of sheep, and the larve
132 SANITARY ENTOMOLOGY
breed in the flesh causing external myiasis. This species attacks ulcers
and sores of men and animals. Its most common attack on sheep and
calves is made on the soiled rumps of animals suffering from diarrhea.
No doubt the flies also serve as distributors of the diarrhea.
The larva has eight-lobed anterior spiracles. The same number of
tubercles margin the stigmal plate behind as in Calliphora, but they are
smaller and sharper. The stigmal plates are about one-half their
diameter apart, each with three straight slits, directed somewhat toward
each other, but also downward.
Undoubtedly under battle front conditions this fly can be expected
to visit human wounds and breed in them even more readily than Cal-
liphora. It has been shown by Cao to transmit anthrax with equal
ease.
Several other species of Lucilia have like habits, and the larve of
two of these, L. caesar Linnaeus (not sericata Meigen), and L. syloarum
Meigen have been described and illustrated by Banks.
The larvae of L. caesar measure 10 to 11 mm. in length and have not
adequately been separated from Calliphora erythrocephala. The larval
period averages about fourteen days and the pupal stage about the
same. Bishopp and Laake state that in Texas, during warm weather,
the larval period ranges from three to twelve days, the pupal stage five
to sixteen days and the total developmental period eleven to twenty-four
days. This fly is illustrated in plate I, Fig. 2.
OTHER SCREW WORMS AND BLOW FLIES
The question of myiasis, which covers screw worms and blow flies, is to
be considered in separate lectures (Chapters XII and XIII), but mention
must be made of them at present because undoubtedly many infectious
diseases are carried by these insects which attack alike live flesh through
wounds, and dead animals. I would hardly hesitate to claim that
probably all such flies may carry anthrax at least, and probably do carry
other diseases.
Bishopp, Mitchell, and Parman (1917) describe quite fully the habits
of the common American screw worm, Chrysomya macellaria Linnaeus *
(plate I, fig. 3, plate IT) which breeds in both carcasses and flesh wounds
(plate IV). They also treat the black blow fly Phormia regina Meigen
(plate I, fig. 4), and other species. The large hairy blow fly, Cynomyia
cadaverina, Robineau-Desvoidy, and the gray flesh flies Sarcophaga
texana Aldrich, S. tuberosa var. sarracenioides Aldrich, §. sarraceniae
*An appeal has been made to the International Commission on Zoological Nomen-
clature to retain Chrysomya in the sense with macellaria as type.
PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 133
Puate I.—Screw worms and blow flies. Fig. 1 (upper left).—The blue bottle fly, Cal-
liphora vomitoria, Fig. 2 (upper right).—The green bottle fly, Lucilia caesar. Fig.
3 (lower left).—The American screw worm, Chrysomya macellaria. Fig. 4 (lower
right).—The black blow fly, Phormia regina. (Howard and Pierce, photos by
Dovener.) :
134 SANITARY ENTOMOLOGY
Pirate II.—Eggs of the American screw worm, Chrysomya macellaria, on meat.
(Bishopp.)
PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 135
Riley (plate II, fig. 1) and S. robusta Aldrich are also among the most,
common flesh flies.
Froggatt (1915) has given a very fine treatment of the most impor-
tant sheep maggot flies and has presented colored illustrations of some
of them.
All of these flies are likely to be found in houses and markets and
when given the opportunity will lay eggs on meat offered for sale or
exposed in kitchens or mess halls. If this meat is already cooked there is
a good chance of the eggs being ingested and giving rise to gastrointestinal |
myiasis. But the danger from flesh flies is greater than the mere
causation of external or internal myiasis. The flies which lay the eggs
may have bred in diseased carcasses, and if so, probably will deposit with
the eggs a glutinous film containing bacteria from these carcasses, for it
will be remembered that the fly larva takes up these bacteria and they
may remain in its body until it as a mature fly lays its eggs, and even
longer. It must be borne in mind that because conditions in the imme-
diate vicinity are sanitary, does not mean that the flies which come
are sanitary, because Bishopp and Laake (1919) record the flight of
marked Chrysomya macellaria flies for 15 miles, and of Phormia regina
for 11 miles.
OTHER EXCREMENT BREEDERS
Others of our house flies, as the non-biting stable fly, Muscina
stabulans Macquart (plate III, fig. 2), the lesser house fly Fannia cant-
cularis Linnaeus (plate III, fig. 3), and the latrine fly F. scalaris
Fabricius breed in decaying vegetables and animal matter.
Muscina stabulans looks very much like the house fly, but it is a
little more robust. It is gray and the thorax is marked with four
longitudinal black lines. Parts of the legs and scutellum are reddish.
The principal differential character is in the wing venation. The larva,
however, is easily distinguished from Musca domestica, by the six-lobed
anterior spiracles and the anal stigmal plates scarcely elevated, less
than their diameter apart, each with three very short slits pointing
towards those of the opposite plate. It breeds in decaying and live vege-
table matter, human and animal excreta, and has even been reared from
insect puparia. It breeds likewise in raw and cooked meats and on car-
casses. It is therefore a very potential disease carrier, possessing all
the opportunities of the house fly, with which it may already be mixed
in medical literature.
Fannia canicularis and F. scalaris are two flies commonly found in
houses, which greatly resemble the house fly, but the former may be dis-
tinguished by the presence of only three dark stripes on the thorax
instead of the four found in the house fly. The larve of these flies are very
136 SANITARY ENTOMOLOGY
Prate III.—Flies with dangerous habits. Fig. 1 (upper left)—A flesh fly, Sarcophaga jajaja ya
sarraceniae. Fig. 2 (upper right). —The non-hiting stable fly, Museina stabulans.is.18.18.18
Fig. 3 (lower left).—The lesser house fly, Fannia canicularis. Fig. 4 (lower erererei
right).—The brilliant green fly, Pseudopyrellia cornicina. (Howard “and Pierce, 'e,'e, 'e,'€
photos by Dovener.)
PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 137
readily separated by the large number of processes on all the seg-
ments. The posterior spiracles are located on raised processes and are
not plates as in the species mentioned above. In F. canicularis there
are four lobes to the posterior spiracles and six finger-like lobes to the
anterior spiracles (see Hewitt, 1917) (see figs. 14 to 19).
These flies breed in excrement, and in all kinds of decaying vegetable
matter and are often found in cases of intestinal myiasis.
REFERENCES
Ball, S. C., 1918.—Migration of Insects to Rebecca Shoals Light Station
and the Tortugas Islands, with Special Reference to Mosquitoes and
Flies. Carnegie Inst., Washington, Publ. 252.
Banks, Nathan, 1912.—The Structure of Certain Dipterous Larve with
Particular Reference to Those in Human Foods,
Bishopp, F. C., 1915.—Flies Which Cause Myiasis in Man and Animals.
Some Aspects of the Problem. Journ. Econ. Ent., vol. 8, pp. 317-
829.
Bishopp, F. C., and Laake, E. W., 1919.—The Dispersion of Flies by
Flight. (Abstract) Journ. Econ. Ent., vol. 12, pp. 210-211.
Bishopp, F. C., Mitchell, J. D., and Parman, D. C., 1917.—U. 8. Dept.
Agr., Farmers’ Bull. 857.
Froggatt, W. W., 1915.—Sheep Maggot Flies. meee Agr., New South
Wales, Farmers’ Bull. 95.
Graham-Smith, G. S., 1913.—Flies in Relation to iyieaie: Non-blood-
sucking Flies. Cambridge Univ. Press.
Hewitt, C. G., 1917.—The House Fly. Cambridge Univ. Press.
Howard, L. O., and Hutchison, R. H., 1915.—House Flies, U. S. Dept.
Agr., Farmers’ Bull. 679.
Hutchison, R. H., 1916.—U. S. Dept. Agr. Bull. 345.
Nicoll, W., 1911.—_Journ. Hygiene, vol. 11, No. 3, pp. 381-389.
Parker, R. R., 1916.—Dispersion of Musca domestica under City Condi-
tions in Montana. Journ. Econ. Ent., vol. 9, pp. 325-354.
Patton, W. S., and Cragg, F. W., 1913.—A Textbook of Medical En-
tomology.
Richardson, C. H., 1917.—The Domestic Flies of New Jersey. New Jer-
sey Agric. Exp. Sta., Bull. 307.
Riley, W. A., and Ji channeen: O. A., 1915.—Handbook of Medical
Entomology.
CHAPTER IX
Common Flies and How to Tell Them Apart !
C. T. Greene
Only a few of the very common flies have been included in this chap-
ter; the flies that are likely to appear near any house or in any camp.
All of them may be attracted by the odors of fresh and cooking foods.
In the following pages are presented two tables, one to separate the dif-
ferent species of the adult flies, and the other to separate the different
larve or maggots’ of the flies. All the terms for the different parts of
the flies and maggots have been made as plain as possible so that the
Suctoria! type. B JHING Aype.
Moure FARTS.
Fic. 10.—Mouth parts of flies: a, Suctorial type; 6, biting type. (Greene.)
tables can be used by a non-entomologist. In the first table for the adult
flies is given the style of the mouth-parts (see fig. 10), that is, whether
they are adapted for biting or are simply suctorial, then the common
name is given, and then the scientific name. In the second table the larve
or maggots can be separated into different species. Under the name of
each species, the larva or maggot is described in further detail and here
mention is made as to where the species will breed.
1This lecture was presented September 9, and issued September 11, 1918. It has
been somewhat modified.
138
COMMON FLIES AND HOW TO TELL THEM APART 139
All the Sarcophagid or “flesh flies” can be readily separated from all
the other flies in the following table because their bodies are entirely
gray. The head is rather a bright red, the top of the back has three
parallel dark stripes and the top of the abdomen has lighter reflecting
areas, giving it somewhat of a checkered appearance.
\
TABLE TO SEPARATE THE ADULT FLIES
I. Grayish flies with from two to four longitudinal stripes more or less
indicated on the thorax.
1. Dark gray, medium sized fly; top of thorax with four parallel,
black stripes; sides of abdomen with a large yellow area (variable
in size and never definitely outlined); mouth-parts of the suc-
torial type (see fig. 10a), never for biting; variable in size but
MTUSCA DOMESTICA L
Fic. 11.—Diagrammatic sketch of the house fly, Musca domestica. (Greene.)
average about one-quarter inch in length. The common house fly
(Frontispiece, figs. 11, 12a) also called typhoid fly.
Musca domestica Linnaeus.
2. Brownish-gray fly, slightly larger and broader than the house fly. ~
Top of thorax with two long, parallel, black stripes and on each
side of these is a large black dot, below which is a black stripe
about half as long as the two long stripes. Abdomen with two
or three cone-shaped dark brown spots in the center and two or
three round spots on each side (fig. 12c). Mouth-parts piercing
or biting type (fig. 10b). Stable fly, also called biting house fly
(fig. 46). Stomoays calcitrans Linnaeus.
8. Very dark gray fly, smaller and more slender than the house fly.
. Abdomen pointed and more conical in shape. Yellow spots on the
sides definitely outlined (fig. 12b). Mouth-parts are of the suc-
torial type (fig. 10a). The small house fly (plate III, fig. 3).
Fannia canicularis Linnaeus.
4. Gray fly, a little larger than the house fly. (About the size of
Stomoxys calcitrans.) Top of thorax has two short, black
140
SANITARY ENTOMOLOGY
stripes. Joints of legs reddish at base. Abdomen is gray and
in certain lights there are paler gray areas which look like
spots but there are never any definitely outlined spots. Mouth-
parts suctorial type (fig. 10a). Another stable fly (plate III,
fig. 2). Muscina stabulans Linnaeus.
II. Bluish, or greenish flies.
1.
Large blue fly, with grayish thorax (average length three-eighths
to seven-sixteenths of an inch). This fly is rather broad and
robust and in certain lights the abdomen shows paler, reflecting
areas but not definite spots. Mouth-parts suctorial type (fig.
10a). The common blow fly. Lower part of head (cheeks) red-
dish and the beard black. Calliphora erythrocephala Meigen.
A slightly larger fly than the preceding but more shiny and a
deep greenish blue. Abdomen slightly more pointed and of an
a. b
House Fir Lirree House Fly STABLE Fly
Musca oomesrica.l FANNIA CANT CULARIS.L. STOMOXYS CALCITRANS:
Fic. 12—Abdominal markings of three common house flies: a, the house fly, Musca
domestica; b, little house fly, Fannia canicularis; c, stable fly, Stomowys calcitrans.
(Greene.) In these diagrams the relative size of the abdomen is shown. The
light areas in a and b represent yellow markings and are variable in size. In fig.
ce the markings of the last segment may be present or absent.
even coloration (no reflecting spots). Mouth-parts suctorial type
(fig. 10a). Lower part of head black and the beard red. An-
other blow-fly (plate I, fig. 1). Calliphora vomitoria Linnaeus.
Much smaller fly, shiny green with a decided whitish bloom on
the thorax and abdomen. Mouth-parts suctorial (fig. 10a). A
green bottle fly. Lucilia sericata Meigen.
A slightly smaller fly, shiny, metallic green with a decided bluish
tinge and no white bloom. Mouth-parts suctorial (fig. 10a).
Green bottle fly (plate I, fig. 2). Lucilia caesar Linnaeus.
A dark green fly, little larger than the above species. It is shiny
with bluish tinge. Top ef thorax with three dark longitudinal
stripes. Thorax often has a bronze tinge. (Average length five-
sixteenths to three-eighths of an inch.) Mouth-parts of the suc-
torial type (fig. 10a). The “screw-worm fly’? (plate I, fig. 3).
Chrysomya macellaria Fabricius.
COMMON FLIES AND HOW TO TELL THEM APART 141
6. Deep, shiny blue fly often with a blackish tinge (about five-six-
teenths of an inch in length). Mouth-parts of the suctorial type
(fig. 10a). The black blow fly (plate I, fig. 4).
Phormia regina Meigen.
III. Ashen gray to deep gray flies. Top of thorax with three blackish,
longitudinal stripes. The abdomen has lighter gray reflecting
spots (in certain lights). The different species vary in size
from a small fly up to a half inch in length. Mouth-parts are
of the suctorial type (fig. 10a). Flesh flies (plate III, fig. 1).
Sarcophagidae.
THE LARVAE OR MAGGOTS
There is a considerable number of flies whose larve or maggots
either regularly or-occasionally live in substances used by man as food.
The great majority pass through the intestinal’ tract without our
knowledge, for most of them cause little or no trouble. Many dipterous
larve occur in decaying fruits and vegetables and on fresh and cooked
meats. The blow fly, for example, will deposit on meats in a pantry;
while other maggots occur in cheese, etc. Pies and puddings in restau-
rants are often accessible and very suitable places for flies to deposit
their eggs and no doubt a great many maggots are swallowed in this
way. The occurrence of dipterous larvae in man is known as “myiasis.”
Various names or divisions are given, as “myiasis externa” or “myiasis
dermatosa” for larve in the skin or wounds; “myiasis intestinalis” for
those in the alimentary canal; and “myiasis narium” for larve in the
nose. The presence of larve in the nose is rather accidental in this
country and usually due to the “screw-worm.” In tropical countries this
type of myiasis is quite common.
The larvae of the ox-warble or bot-fly (Hypoderma lineata Villers)
sometimes occur in man. There are various cases recorded, mostly of
children, where, in the winter time, a larva is observed under the skin,
usually in the neck or shoulders, and upon removal proves to be the
larva of the heel fly in the second stage. Bot infestation is sometimes
called “creeping worms,” and many cases have been recorded by army
surgeons on the Mexican border. These cases are probably contracted
by men sleeping in stable yards.
Descriptions of larvae or maggots *
All the larvae mentioned here are broadest near the tip or tail of the
body, and taper forward to the head.
2In the following discussion ‘the visible body segments are numbered from head
to anus irrespective of their scientific nomenclature.—W. D. Pierce.
142 SANITARY ENTOMOLOGY
The larva is divided into fourteen parts, of which eleven are distinct,
called segments, and the first segment is the head. The head appears to
be bilobed, or divided into two parts when viewed from above, and each
lobe bears a minute cylindrical tubercle or papilla (fig. 13). Below is
the mouth opening; at one side and above it is the pair of mandibles or
great hooks (fig. 13). The second segment or prothorax bears on each
side, in the full grown larve, a short fan-shaped process called the an-
terior spiracle. The eleventh body segment which might be taken for the
last is often a fusion of the seventh to tenth abdominal segments. The
eighth abdominal segment can always be identified by the stigmal plates
Stigmal field (containing posterior stigmal plates)
Paptlls
gue tubercle. Ventra/, (fusiform area, Latera/, (fusiform ared.
2
S
x Anterior spiracle.
Re
%
g
Fic. 13.—Characters of a muscid fly larva. (Greene.) Segment 1 is the head; 2-4
are thoracic segments; 5-11 are abdominal. Segment 11 really contains the seventh
to tenth abdominal segments, the spiracles being on the eighth, the anus in the tenth.
or lobes. The ninth and tenth are usually small and ventral and enclose
the anus. For further details see fig. 13.
Table to Separate the Larvae (Maggots)
I. Spiny larve.
1. A larva with the body flattened; down the middle of the back are
two rows of spines or processes, there are also two rows along
the under side and a single row of spines along each side. These
spines or processes are pointed and covered with many bristles.
There are also two stigmal plates on top of the last segment.
(Figs. 14-16.) Fannia canicularis.
2. The larve of Fannia scalaris are similar (figs. 17-19), but the
processes have fewer side branches.
II. Smooth larve.
A. With.one great mouth-hook; slits in stigmal plate winding.
1. Body broadly rounded at rear end, without spines. Stigmal plate
with three winding slits (figs. 20 to 22). Musca domestica.
COMMON FLIES AND HOW TO TELL THEM APART 143
2. Body same as above species, stigmal plate with three S-shaped
slits (figs. 23, 24). Stomoxys calcitrans.
B. Two great mouth-hooks; slits in stigmal plate not winding.
1. Body slightly rounded at rear end, faintly spined and with three
short, pointed slits in stigmal plate (figs. 25, 26).
Muscina stabulans.
Fic. 14.—Larva of the little house fly, Fannia canicularis. Greatly enlarged. (Howard
and Pierce, drawing by Bradford.)
Fic. 15.—Dorsal view of eighth abdominal Fic. 16—Ventral view of terminal seg-
segment of the larva of Fannia canic- ments of Fannia canicularis; thé ninth
ularis. Very highly magnified. (Draw- and tenth segments are comprised in
the small zone around the anus. Very
highly magnified. (Drawing by Brad-
ford.)
ing by Bradford.)
2. Stigmal plates wide apart, each with three straight slits nearly
transverse to the body and a distinct button (figs. 27, 28).
Calliphora erythrocephala. Calliphora vomitoria.
8. Stigmal plates about half their diameter apart, each with three
straight slits directed somewhat downward (fig. 31).
Lucilia sericata.
4, Stigmal plates less than their own diameter apart, each with
three straight slits pointed downward; no button (figs. 29, 30).
Chrysomya macellaria.
144 SANITARY ENTOMOLOGY
5. Stigmal plates at bottom of a deep pit; each plate has three
slits pointing downward, plates less than their diameter apart; no
button, Sarcophagidae.
‘
Fannia canicularis Linnaeus and Fannia scalaris Fabricius
These larve are brownish yellow in color. The body is quite flattened,
narrow and pointed in front. The peculiar spines or projections on the
body will separate them from the other species. The larva averages
nearly three-eighths of an inch in length (figs, 14-19). (See Chapter
VIII.)
Fie. 17.—Larva of Fannia scalaris, the latrine fly, greatly magnified. (Howard and
Pierce, drawing by Bradford.)
Fic, 18.—Dorsal view of eighth abdominal Fic. 19—Ventral view of terminal seg-
segment of the Fannia scalaris. Very ments of Famnnia scalaris; the ninth
highly magnified, (Drawing by Brad- and tenth segments are comprised in
ford.) , the small zone around the anus. Very
highly magnified. (Drawing by Brad-
ford.)
Since the larve of this genus feed on fruit and vegetables that are
just beginning to decay, one can readily see that they are often swallowed
by people. There are many records of the passage of larve or maggots
of this genus. At least some species of this genus breed in human feces,
therefore they may be possible conveyers of disease.
Musca domestica Linnaeus
e
The larva of the house fly is slender and tapering in front and large
and somewhat rounded behind. From above, the head is divided into two
COMMON FLIES AND HOW TO TELL THEM APART 145
parts with a tiny papilla on each side (fig. 20) and there is but one
great hook. The anterior spiracles (fig. 21) show six or seven lobes;
on the under side of the sixth and following segments there is a trans-
verse, swollen area, wider in the middle and somewhat pointed toward
each end. These areas are provided with minute teeth. The area is
slightly prominent and shows two approximate processes. The stigmal
field is barely if at all concave and not outlined by tubercles; the posterior
spiracles (fig. 22) are prominent, less than their own diameter apart
and each with three winding slits and a button at the base. In some
cases two of the winding slits are apparently connected. The second-
stage larve has two straight slits in each stigmal plate, while in the first
larval stage there are two smaller slits on a tubercle each side of the
Fic. 20 (left).—Larva of Mlusca domestica; dorsal view of head and porthorax. (Greene. )
Fic. 21 (center)—Larva of Musca domestica; lateral view of terminal segments.
(Greene.) The spiracles are located on the eighth abdominal segment. The ninth
and tenth segments are ventral and not very distinct, enclosing the anus.
Fic. 22 (right)—Larva of Musca domestica; enlarged sketch of right stigmal plate.
These plates are less than their breadth apart. (Greene.)
middle and in this stage there are no anterior spiracles. (See Chapter
VIII.) .
The larva of the house fly is rarely swallowed, but there are records
to that effect. It sometimes breeds in decaying fruits and vegetables.
The principal breeding place is in horse manure. It also breeds in human
excrement and because of this habit it is very dangerous to human
beings.
Stomorys calcitrans Linneus
The larva of this species is very similar to that of the house fly, with
a single great hook; the anterior spiracles have five lobes (fig. 23); the
sixth and following segments have each an area on the under side pro-
vided with tubercles; this area is wider in the middle; anal area has two
submedian tubercles and three each side of these; above them is a row
146 SANITARY ENTOMOLOGY
of minute granules, ending each side in a larger granulate tubercle; there
are no tubercles outlining the stigmal field; the stigmal plates are sub-
triangular, about one and one-half times their diameter apart, black,
and each with three pale areas containing an S-shaped slit (fig. 24).
These slits are never near each other like in the house fly, and there is no
apparent button.
This larva commonly breeds in manure of various kinds, but also in
Fie. 23.—Larva of Stomowys calcitrans: enlarged sketch of thoracic spiracles. (Greene.)
decaying matter, and is not often passed by people, but there is one
record. Horse manure, cow manure, and warm, decaying vegetation, like
old straw and grass heaps, are common breeding places.
Fig. 24.—Larva of Stomoxys calcitrans: enlarged sketch of right stigmal plate. These
plates are one and one-half times their breadth apart. (Greene.)
Muscina stabulans Fallen
Head of larva (fig. 25) divided into two parts from above, no dis-
tinct papilla; two great hooks close together; anterior spiracles with
about six lobes (fig. 25b). The surface of the segments is mostly smooth.
Beginning with the fifth segment, on the under side, there is a basal,
transverse, swollen area, furnished on the crest with rows of teeth; each
of these areas is divided on the median line. On the next to the last
segment there is a similar area at the tip, but not divided. The seg-
ments below also show a transverse line before the middle. The last
segment has the anal basal area with spines, but not very prominent,
and bears a median and three lateral tubercles with spines. The tubercles
COMMON FLIES AND HOW TO TELL THEM APART 147
are nearly in a transverse row. The rounded tip of the body (fig. 25c)
shows, across the middle, faint traces of four low cones. The stigmal
plates (fig. 26) are scarcely elevated, black, less than their own diameter
apart, and each with three very short slits pomting towards those of the
opposite plate.
This larva is common in decaying vegetable matter; and has been
reared from rotten apples, pears, squash, mushrooms and dead insect
[
LB
£
Fic. 25.—Larva of Muscina stabulans: a, Side view of head and prothorax; 6b, an-
terior or thoracic spiracles; c, side view of terminal segments of abdomen.
(Greene. )
larve. In one case a considerable number were passed by a child suf-
fering with summer complaint. Laboulbéne records larve of this species
voinited by a person suffering from bronchitis.
Fic. 26.—Larva of Muscina stabulans: enlarged sketch of right stigmal plate. These
plates are less than their breadth apart. (Greene.)
Calliphora erythrocephala Meigen
‘The head of this larva is distinctly divided into two parts from above
(fig. 27, side view of head) ; each part or lobe has a tiny papilla. There
are two well separated mouth hooks. The anterior spiracles have from
nine to twelve lobes. Beginning with the third, each segment shows an
apical swollen ring or girdle, whose surface is scabrous (roughened like
a file); these rings are broader below than above, and are here notched
on the posterior middle. Each ventral segment, beginning with the fifth,
is divided by a transverse groove near the middle. The anal area shows
a smooth median process, divided in the middle, and at each outer corner
is a cone. The stigmal field is rather concave, the upper lip with three
small tubercles on each side, the lower lip with two larger tubercles on
each side, and a median pair smaller and lower down. The stigmal
plates are about once and a fourth their diameter apart, each with three
148 SANITARY ENTOMOLOGY
simple straight slits directed slightly downward but mostly toward those
of the opposite plate; the button is distinct (fig. 28).
The blow-fly deposits eggs on dead animals, and also on fresh and
cooked meats. As such are often accessible to them in pantries, it is
readily seen that many larve are swallowed by people each year; there
are, however, comparatively few records published, probably because the
polluted food causes no trouble.
Calliphora vomitoria Linnaeus
This larva appears to be identical with that of Calliphora erythroceph-
ala. There seem to be no visible characters to separate it from this
latter species (figs. 27 and 28). The habits are about the same.
Fic. 27.—Larva of Calliphora erythrocephala: side view of heed and prothorax.
(Greene. )
Lucilia sericata Meigen
Body rather stout, not slender in front. The head is distinctly
divided into two parts or lobes, with distinct papilla(figs. 31a, b). The
=>
summarizes the results of
these investigations. Those formulae most in use all contain crude
petroleum oil and usually soap.
A good stock emulsion recommended by Graybill is made of:
Hard soap, 1 pound,
Soft water, 1 gallon,
Beaumont crude petroleum, 4 gallons,
Dilute to 1 part emulsion to 3 parts water.
Bishopp’s fly repellent consists of:
Fish oil, 1 gallon,
Oil of tar, 2 ounces,
Oil of pennyroyal, 2 ounces,
Kerosene, 14 pint.
For dairy cattle, Jensen makes a stock solution of crude petroleum
with the addition of 4 ounces powdered napthalin, and applies with a
brush once or twice a week.
Jensen has also given three formule of repellents for protecting
wounds from flies.
Formula No. 1:
Oil of tar, 8 ounces,
Cotton seed oil to make $2 ounces,
Formula No. 2:
Powdered napthalin, 2 ounces,
Hydrous wool fat, 14 ounces,
Mix into an ointment.
Formula No. 3:
Coal tar, 12 ounces,
Carbon disulphid, 4 ounces,
Mix; keep in a well stoppered bottle and apply with a brush.
It is of the utmost importance that flies be kept at a minimum in army
camps. We can do no better than cite a few authorities of the various
armies in support of this. Ainsworth considers the presence of the house
fly the greatest danger signal to an army in the field. Savas has called
*Repellents for Protecting Animals from the Attacks of Flies, U. S. Dept.
Agr. Bul. 131.
166 SANITARY ENTOMOLOGY
attention to the connection of flies with the great cholera outbreak in the
Greek army. At Gallipoli the flies were in amazing numbers, the food was
black with them as soon as it was set on the table. They filled the tents
and shelters, settled on the refuse of the camp, and on the unburied dead,
and by their annoyance multiplied the sufferings of the wounded and
spoiled the tempers of the hale. The flies have been very bad in France.
Kirschner states that in the hospitals near the front the enormous number
of flies presented a serious danger. Maxwell-Lefroy says that in Mesopo-
tamia the tents and trenches were full of flies. ‘The troops at Salonika
suffered greatly from diarrhea and dysentery which coincided in appear-
ance with the abundance of flies. Wenyon and O’Connor found flies in
Egypt largely responsible for outbreaks of amoebic dysentery among the
troops. In this connection Dr. Ballou’s lecture on flies and lice in Egypt
(Chapter XXXII) will give an excellent first-hand view of conditions
in that country.
CHAPTER XI
Control of Flies in Barn Yards, Pig Pens and Chicken Yards +
F, C. Bishopp
The question of the control of flies in their various breeding media or
places of breeding can not be well divided in the discussion. Attention
has been given in a previous lecture (Chapter X) to the general aspects
of house fly control and the most favorable breeding media and methods
of handling them have been discussed in a general way. Therefore I shall
take up the special problems under the three situations listed in the
title. Adequate care of the manure and other refuse in these situations
will not only result in the prevention of breeding of house flies in them
but will also reduce the number of certain other flies which play a part in
disease dissemination among man and animals, notably the horn fly, stable
fly, Muscina spp., Fannia spp., certain Sarcophagids and lesser‘ numbers
of Muscidae known as blow flies, which occasionally breed in hog manure
and freely in unconsumed animal matter in garbage.
REPRESSION OF FLIES IN BARN YARD
The discussion of this problem is bound up closely with that of the
control of the house fly through the care of horse manure, etc. If
manure is promptly disposed. of as removed from the barn the yards are
kept in better condition and the scattered droppings either of horses or
cattle are less dangerous as regards fly’*breeding. In drier regions of the
country these droppings may be practically neglected. Where large
numbers of horses are kept in sheds or yards, the entire area requires
treatment. The manure should be scraped up at least as frequently as
three-day intervals and scattered thinly on fields or composted and
treated with borax or other larvicides.
In large stock concentrating points where stockyards and mule sales
stables are of great extent the problem of disposing of the manure from
the yards is a difficult one. In the Eastern States it has been the usual
practice to contract the manure to certain companies or to permit farmers
and truckers to enter the yards and get manure when they desire it. One
1This lecture was read September 9 and distributed September 11, 1918, and is now
reproduced practically in its original form.
167
168 SANITARY ENTOMOLOGY
difficulty has been that stock are often kept in a single pen for feeding
for some time and during this time it has been the rule not to clean up the
pen. The provision of ample room so that stock may be removed from one
pen to another to permit cleaning is important. This also applies to
horse and mule sales stables. The restrictions placed on the horse and
mule dealers who handle stock fer the army have tended to greatly improve
fly breeding conditions in these stables and yards. I have frequently
observed these sales stables to be filled with tightly packed manure from
eighteen inches to three feet deep. In the case of an East St. Louis
mule sales stable where one company has thirty-five acres under cover,
the removal of all this manure was an enormous task. Yet it was accom-
plished so that the company might continue handling stock for govern-
ment use. The manure was hauled several miles to a fertilizer plant where
the well decayed part was. piled and subsequently dried, ground and sold
as sheep manure for lawn dressings, while the parts with considerable
straw were thrown from cars onto rail incinerators and burned, the ash
being used in fertilizer mixtures. The entire barns and fences were then
gone over with a sand blast machine which cleaned them of all accumula-
tion of dust and saliva which had in some cases become quite thick and
highly glazed. An effort is being made by the authorities in charge to
have the manure from these stables throughout the country moved at
weekly intervals.
The drying of manure and its sale in powdered condition for lawn
dressings, etc., has attained rather large proportions as a commercial
enterprise in some of the large cities. This is a satisfactory means of
disposal of manure and there are good reasons why the practise should
be extended.
It appears that where shavings are used for bedding less trouble
arises from fly breeding than where straw is utilized. This would
undoubtedly favor reduction in the breeding of Stomoxys also.
Returning to the question of handling manure in cow lots and small
barn lots, it is advisable when labor is at hand, especially in dairy yards,
to ick up the droppings daily or even twice a day. This is greatly
facilitated by having the yard where cattle congregate in greatest num-
bers concreted. In large dairy lots it has been found feasible to bring
the manure together by means of an iron road drag (see plate VII). This
leaves the manure in windrows so it can be easily shoveled into a wagon.
For the disposal of manure from dairies and even on the farm no
method is better than the use of a manure spreader (see plate VI) and
the scattering of the material thinly on open fields. Of course in cases
where all land is cropped it is not convenient to employ this method during
certain parts of the year, although it is usually possible to have one
portion of the farm available for manuring at all times.
CONTROL OF FLIES IN BARN YARDS AND PIG PENS 169
The use of manure pits and boxes has been mentioned in a previous
lecture, as has also the Hutchison maggot trap. It appears to the
writer that any attempt to construct pits or boxes which are so tight
as to prevent the escape of newly emerged flies is likely to meet with
failure. In practically all instances the manure is infested more or
less when placed in the box or pit, and following this suggestion the
writer has been advocating the placing of the manure in boxes and pits
which will not allow flies to gain entrance from the outside and which
are provided with a cone or tent trap to capture the flies which breed out
(see plate V). In the absence of the trap feature these would almost
surely escape to the light from the most tightly constructed box or pit
which it is feasible to build and maintain. A manure box of this
type has been tried by the Dallas laboratory and found to work admir-
ably. The number of flies caught is often surprisingly large.
For small pastures and meadows it is sometimés feasible to utilize a
brush drag to break up the cow droppings. This serves three purposes—
preventing the breeding of the horn fly, scattering the manure evenly
over the ground, and permitting the grass to grow where it would other-
wise be prevented by the piles.
While the house fly does not breed readily in pure cow manure the
writer has -reared the species from this substance and has also found
that where cow manure is mixed with a certain. amount of straw it is a
fairly good breeding medium for this species. The horn fly, Lyperosia
trritans (Haematobia) Linnaeus, breeds exclusively in cow droppings
either in large piles or individual droppings. Blow flies are not known to
breed in cow manure, but a number of species of Sarcophagids, most of
which, however, do not have scavenger habits, breed in considerable num-
bers. The brilliant green fly, Pseudopyrellia cornicina Fabricius (plate
III, fig. 4), is very commonly seen on fresh cow droppings; in fact this is
usually the most abundant species in this situation in the country. It
may be readily mistaken for Lucilia when not examined carefully. This
species is of no importance as a human disease carrier as it does not
enter houses or visit food.”
In preventing flies breeding in yards it is very essential that water
troughs be kept from running over and whenever overflows or leaks do
occur they should be fixed promptly and the moistened manure and earth
cleaned up and hauled away immediately. Special attention should be
given to accumulations of horse manure in yards along feeding racks.
Here the mixture of horse manure, waste hay and urine forms a satisfac-
tory mixture for fly production,
2 Unquestionably its larvae must have an important réle as regards organisms taken
up from the manure and passed through their bodies, but whether this rdle is to destroy
the organisms or to propagate and distribute is yet to be learned.—W. D. Pierce.
170 SANITARY ENTOMOLOGY
The use of larvicides and other chemical compounds in barn yards is
usually inadvisable. Thorough cleaning ordinarily will handle the situa-
tion. Crude oil has been used in yards where considerable numbers of
horses are kept to permit firm packing of the ground and keep down
dust in dry weather. Borax, either dry or in solution, may be used in
breeding places which can not be cleaned thoroughly. Poultry and hogs
consume large numbers of larve and pupe and scatter the manure so it
will dry out rapidly. These agencies should not be depended upon, how-
ever, to effect control.
The employment of conical fly traps about stables and dairy barns,
if they are kept properly baited, will aid in reducing the number of house
flies. Cheap molasses and water (1 to 3), or milk curd, brown sugar and
water in equal parts form good baits. The latter, if kept moist, will
remain attractive for two or three weeks. It is comparatively unattrac-
tive for the first few days. Hodge type window traps aid in reducing the
house fly and stable fly troubles within barns if the barns are closely
built and the other windows darkened or screened.
FLY CONTROL IN PIG LOTS AND PENS
The hog has been looked upon from time immemorial as a filthy ani-
mal and he is usually compelled to live in surroundings which would never
be tolerated for any other beast.
One of the special problems which confronts the municipal and the
army sanitarian is the utilization on a Jarge scale of city and camp
garbage by hog feeders. There appears to be no more economical way
of disposing of garbage than by this method, but the conditions under
which the feeding is to be done must be given strict attention by sani-
tarians. In the vicinity of nearly every city and large army camp is
located one or more of these garbage feeding plants, the number of hogs
ranging from a few hundred to several thousand. For the most part the
garbage is sold to feeders under annual contract. Army garbage at
least is supposed to be free from glass, cans, coffee grounds, and liquids.
The contractors furnish the garbage cans, remove the garbage daily and
return empty cans which are supposed to be thoroughly cleaned. If the
orange, grapefruit, and lemon peels could be eliminated from the garbage,
the mass of material not eaten by the hogs would be materially reduced.
Garbage feeding plants should be operated under approximately the
following set of rules:
1. Location of Feeding Stations.—Station should be located as far
from habitations as possible and also well removed, two miles or more, from
the city limits or the precincts of an army camp. Our recent experiments
show that flies of various species, including the house fly, travel thirteen
CONTROL OF FLIES IN BARN YARDS AND PIG PENS 171
miles or more under rural conditions, but that there is a rapid decline
in the number of flies which reach points two miles or more from the
source of production. It is also desirable that the pens be located a
considerable distance from main highways, as passing vehicles help to
disseminate the flies.
2. Draimage—Adequate drainage is essential. It is preferable to
have hog-feeding stations located on hilly ground and never on flat areas.
3. Adequate Room.—In feeding garbage it is essential in order to
maintain sanitary conditions that the hogs be given a considerable
acreage. I would place this at a minimum of 225 sq. ft. per hog, or
approximately 190 hogs to the acre. Of course as a general principle in
fattening hogs it is considered necessary to reduce activity by close
penning. It has been proven, however, that hogs make satisfactory gain
when heavily fed if kept in large pastures.
| iN ENO VIEW
Ri A OPEN HOG-FEEDING TROUGH
‘fon: Raps - (er Ararr
i i ni :
pebbles
IK oe en
| soi : [8
5" — 10-9"
2 * Scaee to"
Fie. 36.—Plans of open hog-feeding trough. (Bishopp.)
4, Feeding Troughs and Platforms.—Concrete feeding troughs and
platforms are essential under present inadequate labor conditions. A
number of forms of troughs and platforms may prove satisfactory from
a sanitary standpoint. In some cases feeding floors are used without any
troughs but this necessitates daily cleaning. Under outdoor conditions
such as exist in the South, it is advisable to locate the feeding troughs on
land with pronounced slope. A simple form of construction consists of a
concrete platform about 15 feet wide, length in proportion to number of
“hogs (fig. 86). This should have a backward slope of about 10 inches.
The trough can be formed by setting a plank on edge in the concrete
about three feet from the upper side and parallel with it or by a concrete
ridge several inches high to form the lower edge of the trough. The
upper edge of the platform should be raised so as to prevent water from
washing into the trough and the feed racks to receive the garbage should
be constructed over the front edge of the trough in such a way as to
172 SANITARY ENTOMOLOGY
receive all drip. The lower side should be provided with a concrete ridge
projecting about five inches. This edge along the back will hold most
of the unconsumed garbage, bones, etc., as they are worked backward, and
facilitates thorough cleaning which should be done at not to exceed three-
day intervals.
5. Shade.—lIf location with plenty of trees can be chosen, this is
preferable to sheds for protection from the sun. Where sheds are needed
for protection either from sun or rain, they should be built on well drained
land and never placed over the feeding troughs. They should be seven
feet above the ground so as to permit of easy cleaning. Temporary
shade can be constructed extending a few feet over the troughs if desired.
6. Contracts—Annual or longer contracts with the Army or with
municipalities are far more desirable than monthly contracts as they en-
able the contractor to put up proper feeding facilities which he would not
do under short contracts. Contracts should specify the character of feed-
ing arrangements and penalize failure to keep the premises in satisfactory
sanitary condition. The pens should be given frequent inspection by
sanitary officers.
7. Cleaning of Yards.—In addition to the cleaning of the uncon-
sumed garbage from feeding platform the manure should be scraped up
and disposed of, especially during rainy weather. During hot dry
weather where ample pasturage is used manure is the source of very
little fly trouble. :
8. Disposal of Bones.—Bones which are not retained on the feeding
platform and those which are mixed with uneaten garbage should be
collected at four-day intervals and placed in fly-proof bone racks. These
can be built of lumber and screened on the outside and provided with
fiy-proof cover. It is desirable that the bones be removed entirely from
the premises at frequent intervals.
9. Avoidance of Transporting Flies on Vehicles—If garbage cans
are properly cleaned there is less tendency for flies to follow them than if
left dirty. Washing in a moderately weak solution of cresol tends to
repel flies from them. The trucks should be washed off occasionally.
There is less danger of flies following trucks back to camps when they are
provided with covers.
10. Quantity Fed.—Feeding so much garbage to hogs that it will
not be cleaned up should be discouraged.
11. Final Disposal of Hog Manure and Unconsumed Garbage.—This
material may be scattered thinly over cultivated ground and exposed
to the sun or promptly plowed under. Where material is found to be
heavily infested with maggots, it is advisable to dump it in piles some dis-
tance from the feeding plant and treat it with borax solution. About one
pound of borax should be used to each 8 bushels. If the mass is very wet
CONTROL OF FLIES IN BARN YARDS AND PIG PENS 173
the borax may be applied dry, but if the material will absorb liquid the
borax should be dissolved in water at the rate of one pound to five
gallons and sprinkled over it.
12. Dead Hogs.—Dead hogs should be promptly disposed of either
by burning on the ground or by hauling to rendering plants.
13. Treatment of Hog Pens Where Flies Are Breeding.—All manure
should be scraped up thoroughly, holes cleaned out and the ground
sprinkled with borax solution made as above. The holes should then
be filled and packed ; crude oil will assist in this. Lime has little value in
destroying fly maggots but will tend to dry up moist areas and reduce
odor. Ringing the hogs’ noses reduces the number of holes formed and
is said to help keep them quiet in fattening.
Fly Traps.—Each hog-feeding establishment should be provided with
a number of well constructed fly traps, preferably of the conical type,
and kept well baited. Black strap molasses and water at the rate of 1
part molasses to three parts water may be used as bait, or 1 part dark
brown sugar to 1 part vinegar and $ parts water may be used. The traps
should be set in situations where flies tend to congregate and away from
danger of being disturbed.
Hogs should not be tolerated in towns or cities. On farms the same
general rules for elimination of fly troubles should be followed as applied
to garbage-feeding stations. For brood sows, good, dry, clean housing is
essential from both the fly control standpoint and that of successful
breeding.
PREVENTION OF FLY BREEDING IN CHICKEN HOUSFS AND YARDS
Comparatively little attention has been given to control of flies in
poultry houses and yards. This source of fly breeding is one which should
not be ignored as it is present even in far more premises than are manure
piles from horses and cattle. Several species of flies breed in chicken
manure, but the house fly, stable fly and lesser house fly seem to pre-
dominate. The writer has found many cases in the South in which these
species seemed to be passing the winter in chicken manure. This ap-
pears to be a favorable place for the larve to pass the winter as little
heat is generated to hasten transformation and sufficient protection is
afforded to prevent the destruction of the immature stages by cold.
With small flocks of poultry in the back yard the prevention of fly
breeding is not difficult but is very likely to be neglected. We have found
that flies will breed in rather small accumulations of chicken manure on
dropping boards but are produced in greatest numbers if the accumula-
tions are on the soil itself. The weekly cleaning of all excrement from
the dropping boards and floor is sufficient to prevent fly breeding. Usually
174 SANITARY ENTOMOLOGY
it requires more than a few days’ droppings to produce a very favorable
breeding situation. The cleaning of houses is of course facilitated by
having the dropping boards readily removable or the roosts hinged so as
to give free access to the boards. In the South, dropping boards are not
being advocated and very few places are provided with them. In such
houses a concrete floor is very desirable to make cleaning easy, but seldom
found. Sprinkling the dropping boards or floors with air-slaked lime or
dry sand helps to take up the moisture from the manure and reduce the
attraction for flies.
In small places where gardens are available chicken manure can be
used to advantage as fertilizer. Where it cannot be disposed of in this
way promptly it should be placed in a box under cover from rain and
treated with borax as previously recommended.
Dead fowls breed many dangerous species of flies and they should be
disposed of promptly either by a scavenger wagon in a city, or by burning
in rural districts.
The care of yards and houses on large poultry farms should be
handled in practically the same way as the small one just discussed.
There is usually less trouble, however, from these large plants as they
receive more constant attention than the small ones. Pigeonries are also
a source of some fly breeding as the pigeon coops usually are placed in an
inaccessible place and become very filthy. The houses should be made
readily accessible and cleaned occasionally. Pigeons should be kept under
control, and porcelain dishes provided for nests will facilitate cleaning.
The frequent and thorough cleaning up of the manure from all domes-
tic animals and fowls tend to reduce the troubles among them from intes-
tinal parasites. Spraying with standard disinfecting solutions has the
effect of reducing the attractiveness for flies, of excrement, soiled floors,
etc., in addition to the germicidal action. Cleanliness and spraying of
premises also increase the efficiency of fly traps.
CHAPTER XII
Myiasis—Types of Injury and Life History, and Habits of Species
Concerned?
F. C. Bishopp
Myiasis is a term applied to’the attack of living man or animals by fly
larve. The medical profession usually assigns specific names to the
infestations according to their location—as dermal (in or under the
skin), nasal (nose infestation), auricular or otomyiasis (ear attack),
intestinal, etc. These names are not entirely satisfactory as often one
form will develop into another or one species of larvae may be concerned
in attacks in many different regions. And again several species may
attack the same region but produce different types of injury, or the
point of attack may vary with the stage of the larve.
Any attempt to classify the different types of myiasis according to
character or place of attack or species of fly concerned seems to have
its objections and difficulties. For convenience in discussion an attempt
is made to divide the subject from the standpoint of method of attack
into the following groups:
First, TISSUE-DESTROYING FORMS, including those species
which are ravenous feeders and destroy living tissues. For example the
screw-worm, Chrysomya macellaria Linnaeus. The species which are
included in this group with the exception of Wohlfahrtia magnifica
Schiner attack living animals secondarily, the main source of breeding
being in dead animal matter.
Second, SUBDERMAL MIGRATORY FORMS which are parasitic
in animals or man and occur during the major part of their lives beneath
the skin. For example, the ox warble, Dermatobia or “torcel,” in
man, etc.
Third, LARV INFESTING THE INTESTINAL OR UROGENI-
TAL TRACTS. These usually feed to a lesser or greater degree on food
or excrementitious matter within the body. For example the larve of
the latrine flies of the genus Fannia and of certain flesh flies of the family
Sarcophagidae. Infestations largely accidental, except horse bots and
related species in animals which are truly parasitic.
Fourth, FORMS INFESTING HEAD PASSAGES. ‘True parasites
1This lecture was presented November 18 and distributed December 20, 1918.
175
176 SANITARY ENTOMOLOGY
of animals or man occurring in the head sinuses, throat, or occasionally
the eye. For example, the sheep bot, Oestrus ovis Linnaeus, and the deer
bots, Cephenomyia spp.
Fifth, BLOOD-SUCKING SPECIES. Highly specialized forms with
blood sucking as a normal habit, exclusively parasites of man or animals,
such as the Congo floor maggot attacking man, and larve of the genus
Protocalliphora attacking birds.
Myiasis is caused by many species in several families. The habits,
in regard to myiasis, of the species of any single family vary widely as
might be expected in groups which have become more or less specialized.
For instance, the family Oestridae, which is the only family having all its
species concerned, in myiasis, has members which infest the stomach, others
which develop in the nasal passages and still others which produce
cutaneous myiasis. The family Muscidae also exhibits very diverse habits
in this regard, some members being concerned in destructive myiasis,
others in specialized dermal cases and still others are blood suckers.
Myiasis in animals is not generally considered in connection with
human cases. There exists, however, a very intimate interrelationship ;
in fact, the prevention of myiasis in man is largely dependent upon the
control of the trouble in animals. Entomologists engaged in sanitary
work must be prepared to handle insect attack on animals as well as on
man.
Owing to the need for careful determination of the exact species con-
cerned in cases of myiasis, both for the immediate needs of the case and for
the benefit of science, it is highly desirable that the larvae concerned be
bred to adults whenever possible. Specific determination of the larve,
especially when small, is, to say the least, very difficult, but a few should
be preserved in alcohol for record and future identification when larval
characters are better understood. Some suggestions as to breeding
methods are apropos. There is no use endeavoring to rear Oestrids after
extraction unless well matured. Most of the larve from wounds will
usually develop on beef. Care must be exercised in rearing the flies to
avoid infestation of the material by other species, especially Sarcophagids
which will drop larve through screen wire onto meat or excrement. A
double cage is best to avoid this; one of these should have a solid top.
Good ventilation is important and sand slightly moist but not wet should
be provided beneath the meat. The meat may be partially buried to
retain moisture and reduce odor. It should be remembered that the
larve have a strong tendency to migrate when ready to pupate.
TISSUE-DESTROYING FORMS
It should be said that most forms of larve attacking man or animals
may destroy body cells to some extent but not in the sense of the rapid
MYIASIS—TYPES OF INJURY, LIFE HISTORY, HABITS | 177
tearing away of tissues, as exhibited by species in this group. This is
the most dangerous type of myiasis in man and one of the most important
sources of loss due to insects among domestic animals. As previously
pointed out, practically all the flies included in this group attack living
animals as a secondary method of reproduction.
It should be stated most emphatically that cases of myiasis, either in
man or animals due to species in this group, are more or less intimately
associated with violations of the best sanitary principles. The vast
majority of cases of this type of myiasis occur in the warmer parts
Prate IX.—Carcass partly destroyed by larvae of the American screw-worm fly,
Chrysomya macellaria. (Bishopp.)
of the world. In the United States, as is well known, our principal source
of trouble is due to the Muscoid fly, Chrysomya macellaria Linnaeus,
commonly spoken of as the screw-worm (sce plate I, fig. 3; plate II; plate
IX). Several other species are concerned to a greater or less degree,
among these should be mentioned the black blow fly, Phormia regina
Meigen (plate I, fig. 4), the green bottle flies, Lucilia casar Linnaeus
(plate I, fig. 2) and L. sericata Meigen, certain of the flesh flies (Sarcoph-
aga spp. (plate III, fig. 1) and occasionally some of the hairy blow-
flies of the genera Cynomyia and Cailiphora.
Fortunately from the standpoint of the sanitary entomologist, the
methods of control are in general very much the same for all species of
this group, owing to the similar habits and not vastly different life his-
178 SANITARY ENTOMOLOGY
tories. All of the species, except Wohlfahrtia magnifica Schiner, are
carrion breeders although the adult flies are attracted to various kinds
of food, especially those with strong pungent odors as come from the
cooking of cabbage or turnips. A few develop occasionally in human
excrement; normally, however, the decomposition of animal matter has
the strongest attraction for them and in many regions it is with great
difficulty that animals can be slaughtered without having the meat
contaminated by their presence in large numbers (see plate II). Garbage
containing meat and bone will attract and breed them.
America.—The screw-worm fly occurs throughout the United States,
but is of little importance as a pest except in the Southwest where in
some sections it is a veritable scourge to the raisers of livestock.
The life history of this species will serve as an illustration for this
group of flies in the United States. The eggs are deposited on carrion,
especially on animals which have died recently. These hatch in a few
hours into maggots which enter the tissues rapidly and become mature in
about six to twenty days. In living animals development seems to be
rather more rapid. Pupation takes place in the soil from the surface to
three or four inches deep and the flies emerge in from three to fourteen
days. The total development period from attack to adult has been found
to vary from seven to thirty-nine days. The activity of this species is
confined to the warmer part of the year, usually from about April first
to November first in the Southern States. The black blow fly, Phormia
regina, on the other hand, appears more resistant to cool weather and
becomes most numerous in the southern region during early spring and
late fall. This is also true to a large extent with the large hairy blow-
flies. These latter entirely disappear during the summer months in the
southern latitudes.
Infestations of screw-worms in animals occur on any portion of the
body where there is broken skin or even on sound skin where blood spots
occur. For the most part, however, the infestations follow mechanical
injury or where ticks have been crushed on the host. In man practi-
cally any part of the body may be attacked, but the most common
type of myiasis is nasal. This is especially true in Central and South
America. Such infestations are usually associated with malignant
catarrh or bleeding from the nose, and practically always with careless
modes of living. The larve enter the nose and penetrate the tissue,
rapidly producing extensive cellulitis and usually accompanied by con-
siderable serous or bloody discharge. If not detected for two days the
injury is likely to be very serious. The frontal and ethmoid sinuses may
be entered and the cartilage and even the bone attacked. Often the
tissues of the nose and beneath the eyes begin to collapse and sometimes
excavation reaches to the surface, giving permanent disfiguration. This
MYIASIS—TYPES OF INJURY, LIFE HISTORY, HABITS 179
extensive destruction of tissues often results in septicaemia or meningitis.
Infestation of wounds on the battlefield or even in hospitals is not at all
infrequent, but such cases are much more easily treated than nasal infes-
tations, ;
The black blow fly, Phormia regina Meigen, usually infests only old
suppurating wounds. In livestock it is commonly found following dehorn-
ing and has also been proved to be a common source of wool infestation
of sheep in the Southwest. In the latter case the soiled wool following
lambing attracts flies and the maggots feed on this for some time but
later may enter the sheep itself and cause its destruction.
The green bottle flies, Lucilia sericata Meigen and L. cesar Linnaeus,
which are commonly known as the wool maggots in the British Isles,
occur throughout the United States. They have been known to infest
wounds in man and animals but the main source of trouble has been the
infestation of soiled wool on sheep. The method of attack in wounds is
similar to that of screw-worms, but the tissue destruction is less rapid
although this depends largely in either case upon the number of larve
present. They are more abundant in towns than in open country.
In South and Central America and the West Indies, Chrysomya
macellaria abounds and gives similar troubles to those in the United
States. In Brazil, Sarcophaga lambens Wiedemann and S. pyophila N.
& F. have been reported by Neiva and De Faria to infest wounds. In
Hawaii Calliphora dux (Thompson) has caused considerable loss by
attacking soiled wool and scabs on sheep.
Evrore.—In Europe the principal trouble from myiasis occurs in
southern Russia. A considerable number of cases occur in the Mediter-
ranean region and some farther north in Australia and Germany. In
southeastern Russia, according to Portchinsky, the vast majority of cases
of this type are caused by the flesh fly, Wohlfahrtia magnifica Schiner,
which appears to have habits of attack on man and animals very similar
to that of the screw-worm fly in America. He speaks of its attack usually
following wounds on the bodies of cattle, horses, pigs, dogs, and poultry.
It also commonly infests the feet of animals suffering from foot-and-
mouth disease. The cases in man occur most commonly in the nose, ears,
and eyes. The injury is often serious, resulting in deafness, blindness,
or facial disfiguration, and not infrequently in death. This fly deposits
living larve, and infestations in man are usually the result of sleeping
outdoors during the warm part of the day. The fly is most abundant
in fields and woods rather than in towns. It is said to breed in living
animals only, thus differing in an important respect from the screw-
worm fly.
While this species is not commonly spoken of as a pest in western
Europe, Liitje reports considerable trouble from it in the western war
180 SANITARY ENTOMOLOGY
theater, especially during 1915. It infested wounds and interfered with
their proper treatment and also was responsible for many infestations
of the genitalia of cows in that region.
Next in importance comes the flesh fly, Sarcophaga carnaria Linnaeus.
This form does not seem so prone to attack living animals as Wohlfahrtia
magnifica Schiner, but there are numerous cases of myiasis in old sup-
purating sores. These may occur in any part of animals or man. In the
Petrograd district Lucilia caesar Linnaeus is responsible for some cases of
myiasis, while in Denmark, Holland, and parts of Germany and France,
L. sericata Meigen is concerned in the infestation of wounds. Calliphora
erythrocephala Meigen, Musca domestica Linnaeus and Muscina stabu-
lans Fallén (plate ITI, fig. 2) are said to oviposit on corpses on the battle-
field soon after death but before putrefaction sets in.
The larve of Anthomyia pluvialis Linnaeus has been reported as being
concerned in auricular myiasis. Probably this species should be con-
sidered as a feeder on excreta rather than placed with tissue-destroyving
forms.
Arrica.—Wohlfahrtia magnifica Schiner is reported by Gough in
Egypt as being taken from ulcers behind the ears and from orbits of
patients in the ophthalmic hospitals. In tropical Africa Lucilia argyro-
cephala Wiedemann commonly attacks mammals, man, and birds. Mem-
bers of the genus Pycnosoma, which has been included with Chrysomya
by some authors, cause myiasis in numerous caases. Pycnosoma megaceph-
ala and P. bezziana Vill. are frequently mentioned in literature in con-
nection with cases of myiasis in cattle, horses, camels, and other animals,
as well as man. P. putoriwm Wiedemann, P. marginale Wiedemann and
Chrysomya chloropyga (Wiedemann) Townsend are also concerned.
Sarcophagids have been recorded as infesting wounds; S, haemorrhoidalis
Fuller and S. regularis Wiedemann being mentioned in particular.
Asta.—While there are numerous references to myiasis cases in Asia,
our knowledge of the species concerned is limited. Members of the genus
Pycnosoma, particularly P. flaviceps Walker, are concerned with cases in
India. This species and Lucilia serenissima Fabricius have been men-
tioned particularly as being troublesome by attacking cattle after out-
breaks of foot-and-mouth disease. It is possible that they may be con-
cerned with the spread of this disease in addition to the injury wrought
hy their burrowing into the tissues. The cosmopolitan Lucilia cesar
Linnaeus is responsible for some cases of myiasis. Several Sarcophagidae
have been reported as causing nasal myiasis of man in parts of India, but
most of these have not been specifically determined. S. ruficornis
Fabricius seems to be among those most frequently concerned.
Avstratisa.—While reports of destructive myiasis in man are com-
paratively few from Australia, certain parts are subjected to veritable
MYTASIS—TYPES OF INJURY, LIFE HISTORY, HABITS 181
plague of myiasis among sheep. The center of the region where this
scourge occurs is in New South Wales, where work for the commonwealth
government has been carried on by Professor W. W. Froggatt for several
years. Only a brief mention of the species concerned and the character
of attack can be given.
The loss is brought about through the blowing of the soiled wool,
particularly around the vents of the ewes. The infestation, if not
promptly treated, spreads forward in the wool, resulting in a large loss in
the clip and often the larve gain entrance to the bodits of sheep and
cause their death. Even though penetration does not occur, the skin is
acutely inflamed and gives rise to fever, loss of appetite, and sometimes
death. Froggatt states that he has bred 1,050 flies from the maggots in
one pound of wool.
Froggatt holds that the blowing of wool is largely an acquired habit
on the part of Australian flies, as practically no cases of this kind were
noted up to 1903 or 1904. He attributes the acquisition of this habit to
the extended drought which destroyed large numbers of animals of all
kinds and resulted in the production of myriads of flies. He thinks that
during this period several species of flies acquired the habit of depositing
in “smelly” wool. He also considers the more extensive breeding of heavy
wooled sheep to be a contributory factor. It is certain that injury from
blow-flies has developed from an almost unnoticed trouble to a problem
of first magnitude within the space of a few years. During the first
few years of the acute trouble the small yellow house fly, Anastellorhina |
augur Linneus, and the golden hair blow-fly, Neopollenia stygia
(Fabricius) Townsend (Pollenia villosa Robineau-Desvoidy) appeared
to be the principal culprits. In 1913, when the work was taken up more
extensively it was found that the “green and blue” sheep maggot fly,
Chrysomya rufifacies Macquart (Pycnosoma), was assuming first impor-
tance in connection with the infestation of sheep. The difference in
apparent injuriousness is probably governed largely by the seasonal
conditions as in the case of species in our own country, C. rufifacies appar-
ently being concerned largely with cases of myiasis in summer and A?
augur during the cool weather. The life histories of these flies do not
differ materially from that of the screw-worm fly, the life cycle being
completed in about two weeks under favorable conditions. Other species
which have been bred from wool in Australia are Microcalliphora varipes
(Macquart) Townsend, the Anthomyid, Ophyra nigra Wiedemann,
Sarcophaga aurifrons Macquart, and the cosmopolitan Lucilia sericata
and L. cesar, and possibly L. tasmaniensis.
182 SANITARY ENTOMOLOGY
SUBDERMAL MIGRATORY SPECIES
The species concerned in this form of myiasis are truly parasitic.
In the cases of man they can not be considered as especially dangerous,
but in animals they assume first rank as destructive parasites.
The type of myiasis produced by these larve is described under
various names in medical literature but especially mentioned as creeping
disease. This is owing to the movement of the larve in the subcutaneous
tissues. In the United States we have little concern for cases of myiasis
in man produced by this group of flies as they are comparatively infre-
quent. The species concerned are Hypoderma, probably mostly lineata
DeVillers and Gastrophilus, probably mostly intestinalis DeGeer (plates
X, XII). Unfortunately the larve concerned usually have not been
preserved, and in a very few cases have any larve from man been reared
to maturity.
The sanitary entomologist is not particularly concerned with the
Oestrids infesting cattle, but on account of their importance to the
veterinary entomologist they are here briefly discussed (see plates XI,
XIII). There are two species in this country, H. lineata De Villers and
H. bovis DeGeer. The former is the predominant form in the United
States, especially in the southern three-fourths of the country, while the
latter is more restricted to the northern tier of States, New England and
Canada. The adults are known as heel flies and oviposit on the hairs, prin-
cipally on the legs of cattle. These eggs hatch in three or four days and
the larve penetrate the skin at the point of attachment or in some
instances may be taken in by licking. After several months spent in the
body of the animal they appear during the late fall and winter months
under the hide along the back, forming subcutaneous tumors. When full
grown these grubs emerge from the host, drop to the ground and after
about twenty-five to thirty-five days spent in the pupal stage produce
flies which are ready to attack cattle the first warm days during spring.
Several cases have recently come under the observation of Mr. E. W.
Laake and the writer of the occurrence of this species in the backs of
horses. These are responsible for the production of lesions which prac-
tically render the use of the infested animals as saddle horses impossible
for a few weeks.
There are a number of records of the occurrence of the young larve
of these flies in man, especially children. Attention is usually first called
to them on account of pain, soreness or itching in the region of the
shoulders or face. The irritation is sometimes rather acute and its
location moves with the burrowing of the larve. Before becoming mature
the grubs appear near the surface under the skin or beneath the mucous
membranes of the mouth and can there be extracted with ease.
MYIASIS—TYPES OF INJURY, LIFE HISTORY, HABITS — 183
Pirate X.—Horse bot flies. Fig. 1 (upper).—Gastrophilus intestinalis, the common
bot. Fig. 2 (lower).—Gastrophilus haemorrhoidalis, the nose fly. (Dove.)
184 SAN
ARY ENTOMOLOGY
Prare XI.—Phases of the life cycle of bot flies. Fig. 1 (upper right)—Empty eggs
of the cattle bot, Hypoderma lineata, Fig. 2 (upper left)—Eggs of the common
horse bot, Gastrophilus intestinalis. Fig. 3 (center)—Full grown larva of JTy-
poderma lineata. Fig. 4 (lower right)—Empty puparium of Iypoderma lineata.
Fig. 5 (lower left) —Empty puparium of Gastrophilus intestinalis. (Bishopp.)
MYTASIS—TYPES OF INJURY, LIFE HISTORY, HABITS = 185
Prare XII.—Method of attack by the common horse bot, Gastrophilus intestinalis.
Fig. 1 (upper).—Eggs on horse’s legs. Fig. 2 (lower).—Larvae attached to walls
1) of stomach, showing lesions caused by removed bots in center. (Bishopp.)
186 SANITARY ENTOMOLOGY
Prate XIIJ.—Method of attack by the cattle bot, or heel fly, Hypoderma lineata. Fig.
1 (upper right).—F ly ovipositing on cow’s leg. Fig. 2 (upper left).—Portion of
cow’s back showing larvae, empty holes and pus exudate. Fig. 3 (lower).—Heavy-
ily infested cow. (Bishopp.)
MYIASIS—TYPES OF INJURY, LIFE HISTORY, HABITS 187
These infestations probably come about through the accidental
depositions of eggs on the bodies or clothing of man, especially children.
The possibility of this method of infestation is emphasized through the
experience of Dr. Glaser, who while studying ox warbles in Germany had a
fly deposit an egg on his trousers which in due time hatched and the
young larva penetrated the skin of his leg. Later its presence in the
oesophageal region was detected by an uncomfortable feeling. The larva
apparently passed up the oesophagus and later was extracted at the
base of one of the molar teeth.
In instances where the Oestrid fly of the genus Gastrophilus attacks
man the conditions surrounding the infestation as well as the exact
identity of the larva are less well understood. It is supposed that the
young larve are in some way brought in contact with the mucous mem-
Fic. 37.—Full grown larva of the human bot, Dermatobia hominis. (Drawing by
Bradford.) Actual length 14.5 mm.
branes of the lips, mouth or eyes and penetrate them, later appearing
under the skin and moving about in a manner somewhat similar to
Hypoderma. The life history of the species of this genus will be dis-
cussed under intestinal myiasis.
AmeErica.—In America in addition to the Hypodermas we have among
the lower mammals dermal myiasis produced by several different species
of Oestrids in the genus Cuterebra. These are most commonly met with
in rabbits, squirrels and certain field mice. Usually they appear to cause
no serious injury except in the case of one form, which is prone to
attack the testicles of squirrels and was given the name of Cuterebra
emasculator Fitch (equals C. fontinella Clark).
In South America a very interesting and more important form of
myiasis in man occurs. This is produced by the Oestrid, Dermatobia
hominis (Carl Linné, Jr.) (nowialis Goudot, cyaniventris, Macquart)
(fig. 37). This form appears to be normally the parasite of cattle, horses,
donkeys and certain wild animals. It is reported as being a serious pest
188 SANITARY ENTOMOLOGY
of cattle, in some cases causing the death of many calves, especially when
the cutaneous tumors become infested with larve of Chrysomya.
The life history and habits of the species have not been fully eluci-
dated, although a number of important contributions have been made.
It is generally concluded that the infestation of man is brought about in
the following indirect but very interesting manner: The eggs of the fly
are deposited on the bodies of certain bloodsucking insects, especially the
mosquito known as Psorophora lutzi Theobald (Janthinosoma), or
attached to leaves frequented by these insects whence they adhere
to them. The eggs are attached vertically on the under side of the
abdomen or the legs. The embryos appear to remain dormant though
fully developed within the egg and when the bloodsucking dipteron
finds a host, the heat of the animal or the blood taken up stimulates the
larve to break from the shell and penetrate the skin of the host. Dermal
tumors are formed by the larve, a well-marked hole opening to the outside
as in the case of the ox warble. When the grubs become full grown they
leave the host, drop to the ground and transform to adults. The period
in the host ranges from two to six months. During this time there is
more or less inflammation and sometimes acute pain. This form is widely
distributed through tropical America. Lieut. L. H. Dunn has recorded
cases of apparent transmission of the eggs by ticks.
In South America Dr. J. C. Nielson has reported the occurrence of the
Anthomyid flies (Mydaea anomala and M. torquens) as producing’subcu-
taneous tumors in various birds in parts of Argentina, and Dr. C. H. T.
Townsend records M. spermophilae as parasitic on nestlings in Jamaica.
Evrope.—Several cases of dermal myiasis have been reported, espe-
cially from Russia. These are attributed to infestations of larve of
Hypoderma and Gastrophilus.
The infestation of reindeer in Lapland and farther south in Norway
by larve of the Oestrid fly, Oedemagena tarandi Linnaeus, should be
mentioned. The infestations are almost analogous to those in cattle
caused by Hypoderma. The eggs are laid on the hair during the spring
and later the larve appear in the submucous tissues of the back. As
many as 300 have been reported as occurring in a single animal. This
same species no doubt infests the reindeer in Alaska and Canada.
Arrica.—In Africa the outstanding form of dermal myiasis is pro-
duced by the Muscid fly, Cordylobia anthropophaga Griinberg, commonly
spoken of as the Tumbu fly (figs. 38, 39). The larve are known as “Ver
du Cayor.” These develop in the skin of man and various other hosts
including dogs (probably the preferred host), cats, horses, and other
domestic and wild animals. The attack is painful but not serious, though
no doubt when numerous specimens are present unpleasant symptoms fol-
low. The life history of this form has not been entirely elucidated, but
MYTASIS—TYPES OF INJURY, LIFE HISTORY, HABITS 189
it is generally believed that the eggs are deposited on the ground in places
frequented by hosts and the larve hatch and penetrate directly through
the skin. In some cases it appears that eggs have been deposited on
clothing, especially if moist with perspiration. They appear in March
ASET
Fic. 38.—Full-grown larva of the Tumbu-fly (Cordylobia anthropophaga, Grinberg).
Ventral view. X 6. (From Austen.)
Fic. 39.—The Tumbu-Fly (Cordylobia anthropophaga, Grinberg). Female. X 6.
(From Austen.)
and diminish until some time in September when they entirely disappear.
Experiments conducted by Roubaud indicate that the choice of host
depends mainly on body temperature, the high temperature of hogs and
fowls being fatal to the larve.
Cordylobia rodhaini Gedoelst is the cause of cutaneous myiasis in the
190 SANITARY ENTOMOLOGY
forest regions of Africa. Man is an accidental host, the species normally
infesting thin skinned wild mammals. According to Rodhain and
Bequaert, who have given much attention to the biologies of this and
related species, the eggs are deposited on the ground in the burrows fre-
quented by the animals, the larve hatch out and penetrate the skin when
the hosts are lying upon them. The larve develop within the host in
twelve to fifteen days. The pupal stage, which is passed in the ground,
ranges from twenty-three to twenty-six days, the life cycle being about
forty days. Another Muscid genus, Bengalia (especially B. depressa
Walker), causes cutaneous myiasis in man in Rhodesia and other parts of
Africa. The eggs are deposited on the clothing or person of man and
on the hair of animals.
Another interesting form is Neocuterebra squamosa Griinberg, which
develops in the adipose tissues in the soles of the feet of the African
elephant.
INTESTINAL AND UROGENITAL MYIASIS
There is every reason to believe that myiasis of the intestinal tract
and urogenital openings results largely from careless modes of living.
The types of myiasis included in this group should not be confused with
urogenital myiasis caused by Chrysomya and related forms. ( ve )
animal, 330-348
in Egypt, 452
Life zones of temperature and humidity,
98-104
rmnopinias flavicornis, caddice fly, 59,
3
griseus, caddice fly, 59, 83
lunatus, caddice fly, 59, 83
rhombicus, caddice fly, 59, 83
Limosina punctipennis (see Borborus)
Linognathus pedalis, sheep foot louse, 345
stenopsis, goat louse, 346, 347
vituli, cattle louse, 288.
Linseed oil for cattle lice, 334, 335
Lion, 373, 405
Liponyssus bacoti, mite, 404, 474
Lipoptena cervi, fly, 235
Lithobius forficatus, centipede, 466, 490
melanops, centipede, 466, 490
Living quarters, 327
Lizards, 226
Llama, 405
Loasis, 482
Lone Star tick (see Amblyomma ameri-
canum)
Loschia coli, amoebid, 116
histolytica, amoebid, 117, 478
Louse, body (see Pediculus corporis)
crab (see Phthirus pubis)
control, 312-329
head (see Pediculus humanus)
ravages, 312, 313
Louse reservoirs, 313, 314
Louse borne diseases, 286-297
Louse-ulcers, 287
Lucania parva, fish, 282
> venusta, fish, 282
Lucilia spp., flies, 117, 118
argyrocephala, fly, 180, 485
caesar, green bottle fly, 105, 108, 109,
110, 111, 112, 113, 114, 132, 133, 140,
177, .179, 180, 181, 453, 475, 477, 485,
492
nobilis, fly, 149
serenissima, fly, 117, 118, 180, 480, 485
sericata, green bottle fly, 131, 132, 140,
143, 148, 149, 177, 179, 180, 181, 453,
485
sylvarum, fly, 132
tasmaniensis, fly, 181, 485
Lungs, inflammation of, 408
Lycosa narbonensis, spider, 463, 489
tarantula, spider, 463, 489
Lymantria. monacha, moth, 467, 489
Lymphangitis, 69, 409
epizootic, 411, 482
Lymph-scrotum, 69
Lynchia spp., flies, 235
brunea, fly, 212, 482
maura, fly, 212, 213, 219, 482
INDEX
Lyperosia sp., fly, 214, 218
exigua, horn fly, 215, 232, 494
irritans, horn fly, 169, 210, 232, 233, 234,
475
minuta, fly, 215, 494
Macracanthorhynchus hirudinaceus, thorn-
headed worm, 79, 85, 86, 495
Macrothylacia rubi, moth, 467, 489
Maculae coeruleae, 288, 482
Mal de caderas, 393, 482
Malacotylea, 120, 121
Malaria, 48, 262
aestivo-autumnal, 253, 255, 256
avian, 259, 482
canary, 482
malignant tertian, 253, 255, 256
pernicious, 252
pigeon, 212, 213, 482
quartan, 253, 256, 257, 482
subtertian, 253, 255, 256, 482, 483
tertian, 253, 257, 258, 259, 483
unclassified, 253, 254, 255, 482
Malassezia spp., fungi, 289, 487
Mallophaga, biting lice, 86
Mange, 405
demodectic, 407, 484
pscroptic, 484
Mansonia sp., mosquito, 250, 485
pseudotillans, mosquito, 262, 480
Mansonioiitdes africanus, mosquito, 261,
262, 479
annulipes, mosquito, 70, 82, 262, 480
uniformis, mosquito, 70, 82, 250, 262, 479
Manure, 153-160
bin, 157
broadcasting, 156
clean-up, 158
collection, 156
hog, 172, 173
incineration, 158
inspection, 158, 160
loading platforms, 156, 158
piles, 159
scraper, 159
shipment, 158
spreader, 157
Margaropus winthemi, tick, 410
Marmoset (see Midas spp.)
Mastigophora, 117-119, 212-219, 249-260,
294-296, 352-355, 388, 393-399, 414-420
Mastophorus echiurus, nematode, 78, 86
globocaudatus, nematode, 78, 85
Mayflies (see Plectoptera)
Mbori, 228, 251, 484
Meal moth (see Asopia farinalis)
Measles, 116, 122, 484
Mediterarnean Coast Fever of cattle, 415,
484
Megalopyge opercularis, moth, 467, 489
Melanodermia, 287, 288, 484
Melanolestes picipes, kissing bug, 469, 489
Melipona spp., bees, 489
Meloidae, 469, 478
INDEX
Melolontha melolontha, June beetle, 79, 85,
495
vulgaris (see Melolontha melolontha)
Melophagus ovinus, sheep tick, 212, 219,
235, 346
Meningitis, cerebrospinal, 108, 115, 289,
290, 484
Meningococcus sp., microdrganism, 289
Mercurial ointment, 337
Meriones spp., rodents, 353
Mermithidae, 78, 262
Mesogoniatus chaetodon, fish, 282
Metatrombidium poriceps, mite, 404, 477
Metazoa, 220, 260, 297, 355, 389, 390
Miana tick fever, 484
Mice, 355, 395
white, 393
Microcalliphora domestica, fly, 485
varipes, fly, 181, 485
Micrococcus sp., microérganism, 292
flavus, microérganism, 108
melitensis, microérganism, 248
nigrofasciens, microdrganism, 383
tetragenus, microdrganism, 108
Microfilaria diurna (see Filaria (Loa)
loa)
perstans (see Acanthocheilonema)
Microneurum funicola, fly, 109, 477
Microtrombidium pusillum, mite, 404, 477
tlalsahuate, mite, 404, 477
wichmanni, mite, 404, 480
Microtus spp., mice, 352
montebelli, field mouse, 413
Midas geoffroyi, marmoset, 259
oedipus, marmoset, 259
Midges (see Chironomidae)
Milk bacteria, 112, 115
Minnow, top (see Gambusia affinis)
Mites, 403-429
Mollienisia latipinna, fish, 282
Mongoose (see Herpestes ichnewmon)
Moniliformis moniliformis, thorn-headed
worm, 79, 84, 88, 389, 495
Monkey, 291, 408
(see Ateles pentadactylus)
(see Cynomolgus cynocephalus)
Morbus errorum, 287
Mosquito control, 275-285
repellents, 284
sources, 276
stains, 276
traps, 283
Mosquitoes, 69, 70, 71, 247-285
Mouse, 408
nematode (see Protospirura muris)
tapeworm (see Hymenolepis diminuta)
tapeworm (see Hymenolepis microstoma)
tapeworm (see Hymenolepis nana)
Municipal boarding houses, 41
Murrina, 119, 122, 484
Mus spp., mice, 352, 353
musculus, mouse, 118, 294
Musca sp., fly, 118
bezzii, fly, 229
511
Musca sp. convexifrons, fly, 229
corvina, fly, 229
domestica, house fly, Frontispiece, 56, 57,
65, 66, 67, 68, 82, 105, 106, 108, 109,
111, 112, 113, 114, 116, 117, 118, 119,
120, 121, 122, 127-130, 139, 140, 142,
144, 145, 151, 180, 477, 478, 479, 480,
481, 484, 486, 487, 488, 489, 4992, 494,
495, 497
gibsoni, fly, 229
nebulo, fly, 118, 121, 487
nigrithorax, fly, 229
pattoni, fly, 229
Muscidae, 228-234
Muscina assimilis, fly, 453
stabulans, non-biting stable fly, 135, 136,
140, 143, 146, 147, 180, 192, 453, 484,
485
Mustela foina, weasel, 73
Mycterotypus bezzii, fly, 224,
irritans, fly, 224
Mydaea anomala, fly, 188, 485
pici, fly, 195, 484
spermophilae, fly, 188
torquens, fly, 188, 485
vomiturationis, fly, 192, 484
Myiasis, 22, 175-208
auricular, 180
bloodsucking larvae, 195, 196, 484
classification, 175, 176
head passage, 193-195, 484
intestinal, 190-193, 484
ocular, 180
prevention and treatment, 200-208
subdermal, 175, 182-190, 484
tissue destroying, 175, 176-181, 485
urogenital, 190, 193, 484
Myobia musculi, mite, 408, 497
Myoxus spp., rodents, 352, 353
Myriapoda, millipedes, centipedes, 88
Mystacides nigra, caddice fly, 59, 83
Myzxococcidium stegomyiae, microérganism,
249
Myxosporidia, 120, 388
Nagana, 214, 228, 230, 250, 393, 485
Nasal myiasis, treatment, 204
Nausea, caused by ‘insects, 21
N.C.I. powder
Necator americanus, hookworm, 122, 480
Nemathelminthes, 121, 122, 220, 261-263,
357, 389
Nematoda, nematodes, 59-78, 88, 121, 122,
220, 261-263, 357, 389, 390
Nematode, bovine, 484
canine, 486
donkey, 486
dromedary, 486
equine, 486
fowl, 486
fox, 486
hedgehog, 486
hog, 486
jerboa, 486
512
Nematode, mongoose, 486
rodent, 486, 487 .
Neocuterebra squamosa, bot, 190, 485
Neopollenia stygia, fly, 181, 485
Neosporidia, 121, 388
Nephrophages sanguinarius, mite, 408, 474
Novem exhaustion, caused by insects, 20,
Neuroctena. amilis, fly, 118
Neuroptera, 59, 82
Nicotin: wash, 337
Nigua (see Dermatophilus penetrans)
Nochelic subzone, 98, 102
Nose protection, 205
Nosema apis, protozoan, 120
Nosemidae, 120
Notemigonus crysoleucas, fish, 282
Notidobia ciliaris, caddice fly, 59, 83
Notoedres cati cati, mite, 405, 491
muris, mite, 491
Nuttallia spp., piroplasmid, 414
equi, piroplasmid, 417, 436, 487
Nuttalliosis, equine, 417, 487
Nycteribiidae, 235
Nyctotherus ovalis, ciliate, 388
Nymphula nymphaeata, moth, 59, 83
Octosporea monospora, protozoan, 120
Ocular acariasis, 487
Odonata, dragon flies, 59, 87
Oedemagena tarandi, reindeer bot, 188,
485
Oestrus ovis, sheep bot, 176, 193, 198, 207,
469, 484
Oilers, 281
Oiling, 280
Oils for treating cattle, 334, 335
Olethric zone, 98, 102
Oligoneuria rhenana, mayfly, 78, 87
Oncocerca sp., cattle nematode, 77
caecutiens, nematode, 77
lienalis, cattle nematode, 77
volvulus, human nematode, 77
Onitis irroratus (see Chironitis)
Onthophagus spp., beetle, 62, 64, 85, 486
bedeli, beetle, 63, 64, 85, 486
hecate, beetle, 62, 86, 485
nebulosus, beetle, 64, 86, 486
pennsylvanicus, beetle, 62, 86, 485
Ophthalmia, purulent, 116, 122, 487
nodosa, 466, 487
Ophyra spp., flies, 453
nigra, fly, 181, 485
Opisthioglyphe rastellus, fluke, 59, 83, 87
Optimum temperature, 100
Organisms carried by insects, 27, 28, 29
Ornithodoros spp., ticks, 423, 424
coriaceus, tick, 4C9, 487
megnini, tick, 408, 420, 424, 426, 431,
433, 434, 444, 445, 487, 490
moubata, African relapsing fever tick,
72, 74, 75, 89, 96, 414, 418, 419, 420,
423, 424, 432, 433, 448, 476, 479, 490,
491, 493
INDEX
Ornithodoros spp., savignyi, tick, 412,
418, 423, 424, 434, 479, 490
turicata, tick, 409, 420
Ornithomyia spp., flies, 235
lagopodis, fly, 213, 214, 480
Orthoptera, 88
Oscinis pallipes, gnat, 119, 497
Otoacariasis, 408, 487
Otodectes cynotis, mite, 408, 487
Otomyiasis, 149
Ovine trypanosomiasis, 218
Owls, 249 ;
Oxyuridae, 121, 389, 390
Oxyuris blattaeorientalis, worm, 389
bulhoesi, worm, 389
curvula, worm, 121, 487
diesingi, worm, 389
kunckeli, worm, 389
vermicularis, worm, 121
Packing house insects, 40, 453-460
Paederus columbinus, beetle, 469, 478
Pahvant Valley plague, 209
Palm squirrel (see Funambulus pen-
natit)
Panama larvicide, 280
Pangonia spp., horseflies, 228
Panoplites sp., mosquito, 75, 82, 479
africanus (see Mansonioides)
Pappataci fever, 49, 211, 226, 487
flies (see Phlebotomus spp.)
Parachordodes pustulosus, horse-hair worm,
79
tolusanus, horse-hair worm, 79
violaceus, horse-hair worm, 79
Paracolitis, 487
Paragordius tricuspidatus, horse-hair worm,
19
varius, horse-hair worm, 78, 79
Paralysis, Australian human tick, 411
infantile (see also Poliomyelitis), 116,
487
insect, 22
North American human tick, 409, 410
South African tick, 410
tick, 487
Paraplasma, flavigenum, protozoan, 259
Paratyphoid A fever, 112, 115, 437
B fever, 112, 115, 487
Partridge, 259
Passer domesticus, English sparrow, 252
Passeromyia heterochaeta, fly, 196, 484
Pasture rotation, 441
Paunch manure, 456
Pecilothermal, 101
Pediculoides ventricosus, mite, 404, 405,
497
Pediculosis, 22
capitis, 286, 287
corporis, 286, 287
Pediculus spp., lice, 481
capitis (see P. humanus)
consobrinus, monkey louse, 302
INDEX
Pediculus spp., corporis, body louse, 286,
289, 290, 291, 292, 293, 294, 296, 301,
302, 304, 305, 306, 307, 308, 309, 310,
317-28, 478, 479, 481, 484, 487, 488, 490,
491, 495, 497
humanus, head louse, 286, 289, 290, 294,
295, 301, 302, 306, 316, 317, 477, 480,
482, 488, 497
vestimenti (see P. corporis)
Pellagra, 212, 225, 230, 487
Periplaneta sp., cockroach, 375
americana, 63, 78, 79, 88, 376, 378, 379,
383, 387, 388, 389, 477, 486, 495
australasiae, 376, 380
Peritonitis, 408, 487
Perlidae, stoneflies, 59
Personal prophylaxis, 315
Pharyngobolus africanus, bot, 193, 484
Phidippus audax, spider, 463, 489
Philaematomyia crassirostris, fly, 215, 494
imsignis, fly, 229
Philaematomyinae, 229
Phlebotomus fever, 211
minutus, fly, 219, 226, 492
minutus africanus, fly, 219
papatasii, pappataci fly, 211, 226, 487
verrucarum, fly, 211, 226, 497
Phormia azurea, fly, 195, 484
metallica, fly, 195
regina, black blowfly, 132, 133, 135, 141,
177, 178, 179, 453, 485
sordida, fly, 195, 484
Phosvhorus, 382
Phryganea sp., caddice fly, 59, 83
grandis, caddice fly, 59, 83
Phthiriasis, 286, 287, 288
Phthirus inguinalis (see P. pubis)
pubis, crab louse, 286, 301, 302, 316, 475,
476, 482, 484, 495
Phyllophaga arcuata, June beetle, 79, 86,
495
Phyllostomus sp. (bat), 251
Physocephalus sexalatus, nematode, 64, 65,
78, 85, 86,°95, 486
Pig (see also hog), 373, 405
nematode (see Arduenna strongylina)
nematode (see Physocephalus sexalatus)
pens and pig lots, 170, 171, 172, 173
thorn-headed worm (see Macracantho-
rhynchus hirudinaceus)
Pigeon lice, 343
Pin itch, 122
Pink eye, 109
Pinworm, equine, 487
Pinworms (see Oxyuridae), 121, 389, 390
Piophila casei, cheese maggot, 192, 454,
484,
Piroplasma spp., protozoa, 414
bigeminum (see Babesia)
hominis, protozoan, 413
Piroplasmidae, 414
Piroplasmosis, 487
Pityriasis, 289, 290, 487
Plague, 49
513
Plague, bubonic, 112, 115, 350, 351, 360,
365, 392, 393, 488
rodent, 114, 115, 209, 230, 351, 488
Planorbis exustus, snail, 260
Plasmodidae, 252, 259
pet sp., malaria organism, 252,
83
danilewskyi, malaria organism, 259, 482
falciparum (see Laverania)
malariae, malaria organism, 253, 257, 482
relictum, malaria organism, 259, 482
vivax, malaria organism, 253, 257, 258,
259, 483
Platyhelmia, 120, 121, 260, 261, 355, 356,
357, 389 .
Plecoptera, stoneflies, 59, 88
Plectoptera, mayflies, 59, 87
Pleurogenes claviger, fluke, 59, 86
medians, fluke, 59, 86, 87
Plica polonica, 287, 488
Plistophora sp., protozoan, 388
periplaneta, protozoan, 388
Pneumococcus septicaemia, 289, 290
Pneumonoeces similis, fluke, 59, 87
Pneumonyssus simicola, mite, 408, 481
Pogonomyrmex barbatus, ant, 468, 488
californicus, ant, 468
Poisoning, bee, wasp and ant, 488
bug, 488 :
centipede, 464-466, 488
food, 111, 114, 115, 489
honey, 468, 489
insect, 21, 22, 461-471
kissing bug, 489
lepidopterous larvae, 466, 489
scorpion, 461-463, 489
spider, 463, 464, 489
Poliomyelitis, 116, 122, 211, 212, 230, 248,
249, 393, 489
Polistes spp., wasps, 468, 488
Pollenia rudis, fly, 118, 192, 484
villosa (see Neopollenia stygia)
Polydesmus complanatus, centipede, 466,
490
Polymastigidae, 117
Polymastigina, 117, 388
Polyneuritis, 291
Polyplax spinulosus, rat louse, 294, 296,
491, 496
stephensi, jerboa louse, 296, 474
Porcellio laevis, sowbug, 68, 89, 486
Porrigo, 289, 490
Porthesia similis, moth, 467, 489
Porthetria dispar, gipsy moth, 467, 489
Pot-holes, 277
Practicotatum,, 98, 100, 101, 102
Priesz-Nocard organism, 411, 482
Prionurus amoureuni, spider, 462, 489
citrinus, spider, 462, 489
Prisoners, inspection, 41
Privies, 37, 39
Prosotocus confusus, fluke, 59, 86, 87
Protection of body against mosquitoes,
283, 284
514
Protomonadina, 117
Protospirura muris, rodent nematode, 60,
78, 80, 86, 93, 357,, 487
Protozoa, 116-120, 212-220, 249-260, 294-
297, 352-355, 388, 393-399, 414-423
Prowazekia sp., protozoan, 117
Prurigo senilis, 287
Pruritis, 287, 288, 409
Pseudoedema, malignant, 386, 490
Pseudoparasitism of nasal passages, etc.,
490
Pseudopyrellia cornicina, fly, 136, 169
Psorergates simplex musculinus, mite, 408,
497
Psorophora lutzi, mosquito, 188
sayi, mosquito, 249, 475
Psoroptes communis bovis, mite, 405, 484
cuniculi, 408, 487
equi, mite, 405, 484
ovis, mite, 405, 484
Psychodidae, 226, 228
Ptinus spp., beetles, 475
Pulex brasiliensis, flea, 352, 496
irritans, human flea, 53, 54, 55. 76, 80,
351, 352, 354, 355, 356, 357, 360, 362,
363, 479, 481, 488, 494, 495, 496
Pupipara, 235
Pus, green, 113, 115
Pustular dermatitis, 287
Pycnosoma bezziana, fly, 180, 485
chloropyga, fly, 485
flaviceps, fly, 180, 485
marginale, fly, 180, 485
megacephala, fly, 180, 485
putorium, fly, 118, 180, 485
rufifacies (see Chrysomya)
Pygiopsylla ahalae, flea, 351, 365, 488
Pyodermia, 287, 288, 490
Pyrethrum powder, 381, 382
Rabbit, 63
fleas, 353
lice, 343, 344
Rain barrels, 282
Rat (see also rodent), 389, 395, 404, 422
fleas, 350, 351
louse (see Polyplax spinulosa)
nematode (see Gongylonema neoplasti-
cum)
nematode (see Protospirura muris)
tapeworm (see Hymenolepis diminuta)
tapeworm (see Hymenolepis nana)
thorn-headed worm (see Moniliformis
moniliformis)
Rat-tail maggots (see Enistalis spp.)
Raven, 249
Red bug, 404
grouse (see Lagopus scoticus)
Reduviidae, 399
Redwater, 414
British, 417, 490
Reindeer bot (see Cephenomyia trompe)
(see Oedemagena tarandi)
Relapsing fever, 48, 403
INDEX
Relapsing fever, Abyssinian, 418, 490
American, 420, 490
Asiatic, 295, 490
East African, 420, 490 .
European, 296, 313, 398, 399, 420, 491
Manchurian, 296 .
North African, 295, 296, 398, 491
Tropical African, 296, 398, 418, 491
Rhiganesthesia, 98
Rhigonochelia, 98, 100
Rhigoplegia, 98, 101
Rhinoceros bots, 193
Rhinoestrus hippopotami, bot, 195, 484
nasalis, bot, 194, 484
purpureus, bot, 194, 198, 207, 484
Rhipicephalus spp., ticks, 424, 435
appendiculata, tick, 417, 425, 436, 447,
478
bursa, tick, 417, 436, 476
capensis, tick, 415, 417
evertsi, tick, 417, 420, 424, 425, 436, 478,
487, 493
sanguineus, tick, 74, 76, 89, 414, 415, 420,
421, 424, 425, 436, 474, 476.
siculus, tick, 410, 414, 417, 425, 474, 476,
478, 487
Rhizoglyphus parasiticus, mite, 405, 408,
481, 487
Rhodesian fever, 417, 491
BRhodnius prolixus, bug, 394, 476
Rhyacophila nubila, caddice fly, 59, 83:
BRhynchoidomonas luciliae, protozoan, 118
Rhyzoglyphus parasiticus (see Rhizogly-
phus)
Rickettsia melophagi, microérganism, 212
pediculi, microdrganism, 292, 294, 497
prowazeki, microorganism, 292, 497
quintana, microérganism, 293, 495
Robin, 195
Rocky Mountain spotted fever, 403, 412,
491
tick (see Dermacentor andersoni)
Rodent trypanosomiasis, 294
Rossiella .spp., protozoa, 414
rossi, protozoan, 417, 474
Sanitation, entomological, 34-42
Sarcina alba, microorganism, 383
aurantiaca, microérganism, 108, 384
lutea, microérganism, 384
Sarcodina, 116, 117, 388
Sarcophaga spp., flies, 119, 453, 484, 497
aurifrons, fly, 181, 485
carnaria, fly, 105, 108, 109, 110, 111, 112,
113, 114, 180, 475, 477, 485, 492
haemorrhoidalis, fly, 118, 180, 191, 484,
485
lambens, fly, 179, 485
murus, fly, 118
pyophila, fly, 179, 197, 485
regularis, fly, 180, 485
robusta, fly, 135
ruficornis, fly, 180
saraceniae, fly, 117, 132, 136
INDEX.
Sarcophaga spp., texama, fly, 132.
tuberosa sarracenioides, fly, 132
Sarcophagidae, 141, 144, 150, 151, 177
Sarcoptes aucheniae, mite, 405, 491
bovis, mite, 405, 491
canis, mite, 405, 491
caprae, mite, 405, 491
dromedarii, mite, 405, 491
equi, mite,,405, 491
leonis, mite, 405, 491
ovis, mite, 405, 491
scabiei crustosae, mite, 405, 491
scabiei hominis, mite, 405, 491
suis, mite, 405, 491
vulpis, mite, 405, 491
Sarcoptidae, 405
Sawdust, oil-soaked, 281
Scab, 491
sheep, 405
Scabies, 48, 405, 491
Scaly leg, 405, 406, 407, 492
Scarabaeus (Ateuchetus) variolosus, beetle,
61, 64, 86, 486
(Ateuchus) sacer, beetle, 61, 63, 64, 65,
86, 486
Scarlet fever, 116, 122, 492
Scatophaga lutaria, fly, 118
Scaurus striatus, beetle, 42, 54, 86, 495
Schistosoma mansoni, worm, 120, 121
Schistosomiasis, 120
Schistosomidae, 120, 121
Schizomycetes, 107-115, 209-211, 249, 289,
290, 350, 351
Schizotrypanum cruzi, trypanosome, 393,
394, 395, 414, 475
Scholeciasis, 22
Schéngastia vandersandei, mite, 404, 480
School children, inspection, 40:
Scolopendra cingulata, centipede, 465, 488
gigantea, centipede, 465, 488
heros, centipede, 465, 488
morsitans, centipede, 465, 488
Scops gin, owl, 249
Scorpion poisoning, 461-463
Scorpionidea, 461
Scouting for mosquitoes, 275
Screening, 162, 206, 283
of food, 39
of houses, 36
Screw worms (see Chrysomya macellaria)
Scutigera coleoptrata, centipede, 466,
490
Scutomyia albolineata, fly, 70, 80, 262, 480
Sebaceous tumor, 408
Seborrhea, 407, 492
Seepage water, 277
Sense organ injury, 21
Septicaemia, 108, 110, 111, 115, 211, 230,
289, 290, 411, 492 F
Serbian barrel disinfector, 322
Setaria labiato-papillosa, cattle nematode,
77, 82, 94
Seven-day- fever, 413
Sewage, 40, 41, 161
515
Sewers, 282
Sheep, 373, 405, 410
bot (see Oestrus ovis)
lice, 345, 346
Sheep maggots, 181
nematode (see Gongylonema scutatum)
tick’ (see Melophagus ovinus)
Shrew tapeworm, 57
Sialis lutaria, dobson fly, 59, 82
Sibine stimulea, moth, 467, 489
Simian trypanosomiasis, 218
Simuliidae, 224, 225, 296
Simulium spp., buffalo gnats, 212, 224,
225, 226, 48%
bracteatum, buffalo gnats, 227
columbaczense, buffalo gnats, 219
dinelli, buffalo gnats, 77
jenningsi, buffalo gnats, 227
pictipes, buffalo gnats, 297
samboni, buffalo gnats, 77
venustum, buffalo gnats, 227
vittatum, buffalo gnats, 227
Siphonaptera (see Aphaniptera)
Sitophilus granarius, beetle, 42
Sleeping sickness, 262
Gambian, 215, 230, 250, 492
Nigerian, 215, 492
Rhodesian, 217, 250, 492
Smallpox, 116, 122, 291, 492
Soaps, 318
Sodium fluoride, 341, 342, 343, 381
Sore, Bagdad, 118, 219, 226, 492
Biskra, 219, 492
Cambay, 118
non-ulcerating oriental, 395
Oriental, 118, 251, 398, 499
tropical, 262
Souma, 217, 228, 230, 493
Zambian, 217, 493
Sowbug (see Porcellio laevis)
Sparrow, 249, 259
Spider poisoning, 463, 464
Spilopsyllus leporis, flea, 353, 496
Spinose ear tick (see Ornithodoros meg-
nini)
Spirillaceae, 115, 387
Spirillum (Vibrio) cholerae, microorgan-
ism, 115, 387, 477
metchnikovi, microérganism,
478
Spirocerca sanguino lenta, dog nematode,
60, 65, 84, 85, 86, 88, 91, 486
Spirochaeta gallica, spirochaete, 293
Spirochaetacea, 219, 259, 260, 295, 296, 355,
398, 418-420
Spirochaetidae, 119, 219, 259, 260, 295-296,
355, 398, 418-420.
Spirochaetosis, 49
bovine, 420, 493
goose, 418, 494
North American fowl, 493
Senegal fowl, 420, 493
South American fowl, 493
Sudanese fowl, 419
387,"
516
Spiroptera obtusa (see Protospirura muris)
(Filaria) sanguinolenta (see Spirocerca)
(Gongylonema) neoplasticum (see Gon-
gylonema)
Spiroschaudinnia spp., spirochaetes, 296,
418, 490
anserina, spirochaete, 418, 494
berbera, spirochaete, 295, 398, 491
carteri, spirochaete, 295, 490
ctenocephali, spirochaete, 355
culicis, spirochaete, 259
duttoni, spirochaete, 296, 398, 491
duttoni, Brumpt, spirochaete, 418
duttoni, Novy and Knapp, spirochaete,
418, 419
exanthematotyphi, spirochaete, 292
glossinae, spirochaete, 219
granulata, spirochaete, 419, 493
marchouwi, spirochaete, 493
neveuxti, spirochaete, 420, 493
novyi, spirochaete, 420, 490
recurrentis, spirochaete, 295, 296, 398,
420, 491
rossti, spirochaete, 420, 490
theileri, spirochaete, 420, 493
Spirura gastrophila, cat nematode, 60, 61,
84, 85, 95, 389, 486
Spiruridae, 121, 357, 389
Splenic fever, 414, 494
Sponge baths, 313
Sprays for cattle, 335, 336
Squirrel, 355, 409
bot, 187
Stable fly (see Stomowys calcitrans)
Stables, 39,40
Staphylinidae, 469, 478
Staphylococcus spp., microédrganisms, 482
pyogenes, microorganisms, 411, 480
pyogenes albus, microdrganisms, 108, 210,
289, 384, 480, 492
pyogenes aureus, microdrganisms, 108,
210, 289, 384, 480, 492
pyogenes citreus, microdrganisms, 108,
492
Steam, enclosed, 322, 323
live, 322
sterilization, 321-323
Stegomyia calopus (see Aedes argenteus)
fasciata (see Aedes argenteus)
gracilis (see Aedes)
ingens, mosquito, 251
Sterilization, steam, 321-323.
Sternostomum rhinolethrum, mite, 408, 481
Stigmatogaster subterraneus, centipede,
466, 490
Stomoxydinae, 229, 230, 232, 233
Stomoxys spp., flies, 217, 218
calcitrans, stable fly, 57, 66, 67, 77, 78,
82, 126, 139, 140, 143, 145, 146, 209,
210, 211, 212, 214, 215, 216, 217, 220,
221, 230, 231, 232, 474, 475, 476, 477,
478, 485, 487, 488, 492, 493, 494, 495
geniculatus, fly, 215
glauca, fly, 214, 485
INDEX
Stomoxys spp., nigra, fly, 215, 216, 217, 220,
476, 493, 494
Stoneflies (see Plecoptera)
Stratiomyia chameleon, fly, 118
potamida, fly, 118
Straw, 231, 232
Streams, clearing, 276
Streblidae, 235
Streptococcus sp., microdrganism, 211, 492
equinus, microdrganism, 107
fecalis, microdrganism, 108
pyogenes, microorganism, 108, 479
salivarius, microdrganism, 108
Strickeria jirgensi, protozoan, 292
Strix flanr2a, owl, 249
Submarine saws, 277
Submersible automatic oil bubbler, 281
Sulphur flowers, 343, 382
fumigation, 381
gas, 324, 325
Suppurating wounds, 113, 494
Suppuration, 108
Surra, 119, 122, 215, 228, 230, 250, 494
Swamp fever, 211
Swamps, 276
Swift (see Cypselus offinis)
Swine (see hog)
Syphilis, 291
Syrnium aluco, owl, 249, 250, 475
Syrup factories, 41
Tabanidae, 211, 214, 218, 219, 228, 236-
246, 251, 496
Tabanus spp., horseflies, 210, 214, 217, 219,
298, 485, 492
atratus, horsefly, 210, 215, 475
biguttatus, horsefly, 215, 217, 484, 493
bovinus, horsefly, 210, 475
chrysurus, horsefly, 211, 474
corax, horsefly, 239, 240
ditaeniatus, horsefly, 237, 242, 243, 246
fasciatus, horsefly, 220
fumifer, horsefly, 215, 494
hilaris, horsefly, 219
kingi, horsefly, 237, 240, 242, 246
lasiophthalmus, horsefly, 243, 244
lineola, horsefly, 215, 494
minimus, horsefly, 215, 494
par, horsefly, 220, 237, 240, 242
partitus, horsefly, 215, 494
phaenops, horsefly, 236, 237, 239, 240,
241, 242, 243, 245
punctifer, horsefly, 236, 237, 238, 239,
240, 241, 243, 245
secedens, horsefly, 220
socialis, horsefly, 220
striatus, horsefly, 210, 215, 219, 240, 241,
242, 243, 244, 245, 246, 475, 494
stygius, horsefly, 239, 244, 245
taeniatus, horsefly, 215, 217, 484, 493
taeniola, horsefly, 237
tergestinus, horsefly, 219
trigeminus, horsefly, 211, 474
trigonus, horsefly, 211, 474
INDEX
Tabanus spp., tropicus, horsefly, 215, 494
vagus, horsefly, 215, 494
vivax, horsefly, 242
Taenia cucumerina, tapeworm, 94
nana (see Hymenolepis)
(Taeniarhynchus) saginata, beef tape-
worm, 120, 494
Taeniidae, 120, 297, 355, 356
Taemorhynchus domesticus, mosquito, 70,
82, 262, 480
fuscopennatus, mosquito, 261, 479
Tahaga, 217, 494
Tapeworm, bovine, 494
canine, 494
fowl, 494, 495
human, 494, 495
rodent, 495
Tapeworms (see Cestoda)
Tarsonemidae, 404
Tarsonemus intectus, mite, 404, 497
uncinatus, mite, 404
Teichomyza fusca, fly, 118
Telosporidia, 219, 220, 355, 388, 420-422
‘femperature, 97-104
and louse development, 304, 306, 307,
309, 310
Temperatures, absolute fatal, 98, 101
Tenebrio molitor, granary beetle, 42, 54,
55, 57, 60, 63, 78, 86, 486, 487, 495
Tersesthes torrens, fly, 224
Testudo mauritanica, turtle, 422, .475
Tetanus, 373, 495
Tetramitidae, 388
Tetranychidae, 404
Tetranychus molestissimus, mite, 404, 481
telarius, mite, 474
telarius russeolus, mite, 404
Texas fever of cattle, 403, 414
Thallophyta, 107-115, 209, 210, 211, 249,
289, 290, 356, 351, 383-387, 392, 393
Theileria spp., piroplasmids, 414
parva, piroplasmid, 417, 478
Thelohania ovata, protozoan, 120
Thelohaniidae, 120, 388
Theobaldia annulata (see Culiseta)
Theraphosa javanensis, spider, 464, 489
Theridium lugubre, kara kist spider, 464,
489
13-guttatum, spider, 464, 489
Thermalgesia, 100
Thermanastasis, 99
Thermanesthesia, 98, 101
Thermesthesia, 100
‘hermohyperesthesia, 100
Thermonochelia, 98, 100
Thermophilic, 100
Thermophobia, 101
Thermophylic, 100
Thermoplegia, 98, 101
Thermopnigia, 100
Thermopolypnea, 100
Thermopractic zone, 98, 99, 102
Thermosystaltic, 101
Thermotaxis, 101
517
Thermotropism, 101
Thorn-headed worms
ala)
Three-day fever, 211
Tick bite, 409
bite fever, human, 410
bite treatment, 448, 449
control, 440-449
dip, 442
fever of Miana, 412
fevers, 412
paralysis (see Paralysis)
Ticks, 403-429
Tile drainage, 277, 278
Tin can dumps, 282
Toilet flushing box, 282
Town, insanitary, 38
sanitation, 38, 39
Toxemia, 287, 288, 495
Toxins, insect, 27
Trachoma, 116, 122, 495
Tragelaphus spekei, antelope, 215
Train disinfection, 322
Traps in sinks, 282
Trash, 41
Trematoda, flukes, 57, 58, 59, 81, 82, 83,
88, 120, 121
Trench fever, 48, 292, 293, 294, 312, 313,
495
Treponema pertenue, spirochaete, 119, 497
Triatoma spp., kissing bugs, 414, 469
chagasi, kissing bugs, 394, 476
geniculata, kissing bugs, 394, 476
infestans, kissing bugs, 393, 482
megista, kissing bugs, 394, 399, 400
rubrofasciata, kissing bugs, 399, 400
sanguisuga, kissing bugs, 400
sordida, kissing bugs, 394, 476
Trichodectes canis (see T. latus)
climax, goat louse, 346
hermsi, goat louse, 346
latus, dog louse, 53, 86, 297, 344, 355,
494,
parumpilosus, horse louse, 347
scalaris, cattle louse, 288, 322, 333
sphaerocephalus, sheep louse, 346
subrostratus, cat louse, 344
Trichomonas orthopterum, protozoan, 388
Trichoptera, caddice flies, 59, 83
Trichosomidae, 122
Trichuris trichiura, whipworm, 122, 497
Trigona sp., honey bee, 22
amalthea, honey bee, 468, 489
bipunctata, honey bee, 468, 489
limao, honey bee, 468, 489
ruficrus, honey bee, 468, 489
Trochosa singoriensis, spider, 463, 489
Trombidium akamushi (see Leptus)
autumnalis, mite, 404, 477
batatas, mite, 404, 477
holosericeum, mite, 404, 477
inopinatum, mite, 404, 477
striaticeps, mite, 404, 477
Troughs, water, 282
(see Acanthoceph-
518
Svat sp., trypanosome, 214, 251,
spp. (see Castellanella, Duttonella,
Schizotryp " Trypano oon)
christophersi, trypanosome, 414
franki, trypanosome, 218
gallinarum, trypanosome, 218, 496
grayi, trypanosome, 218, 496
noctuae, trypanosome, 251
theileri, trypanosome, 218, 480
tullochi, trypanosome, 218
vespertilionis, trypanosome, 395, 495
ziemanni, trypanosome, 251
Trypanosomiasis, 49
animal, 495
bat, 395, 495
bovine, 495, 496
crocodile, 496
equine, 496
fowl, 496
goat, 496
ovine, 496
rabbit, 496
rat, 395
rodent, 496
simian, 496
Trypanosomidae, 119, 214-218, 294, 352-
354, 393-395, 414
Trypanozoon blanchardi, trypanosome, 352,
496
duttoni, trypanosome, 352, 395, 496
lewisi, trypanosome, 294, 352, 353, 395,
496
nabiasi, trypanosome, 353, 496
rabinowitschi, trypanosome, 354, 496
Tsetse fly (see Glossina spp.)
Tsutsugamushi disease, 413, 497
Tuberculosis, 114, 115, 387, 497
Tumbu fly (see Cordylobia anthropophaga)
Tumors, 389
sebaceous, 497
Turkey, 408
dice, 343
Tydeus molestus, mite, 408, 481
Tylenchus sp.. worm, 89
Typhoid fever, 49, 114, 115, 290, 291, 387,
393, 497
Typhus fever, 48, 291, 292, 312, 313, 497
Tyroglyphidae, 405 re
Tyroglyphus longior castellanti, mite, 405,
481
siro, mite, 405, 497
Urine soakage pit, 48
Urticaria, 286, 497
INDEX
Urticariasis, 404, 497
Uta, 219, 224, 497
Vagabond’s disease, 287
Vanillismus, 405, 497
Ver du Cayor (see Cordylobia anthropoph-
aga
Vermicides, 318, 319
Vermijelly, 316
Vermin problem in armies, 45
Verruga peruviana, 211, 226, 497
Vertical drainage, 278
Vespa spp., wasps, 468, 488
Volhynian fever, 294, 497
Vulpes vulpes atlantica, fox, 61
Warbles, treatment, 204, 205
Wart hog, 196
Waste disposal in armies, 44-48
Water beetles, 59, 86
gates, 278, 279
holes, 276
pitchers, 282
Weed-filled bays and lakes, 27
Weep-holes, 277
Weil’s disease, 296
Wells, 37
Whipworm (see Tricharis trichiura)
Withers, fistulous, 412, 497
Wohlfahrtia magnifica, flesh fly, 175, 178,
179, 180, 198, 480, 485
Wolf nematode (see Spirocerca sanguino-
lenta)
Wood owl (see Syrnium aluco)
Wool blowflies, 181
Worms, parasitic, 50-96
Worry caused by insects, 20, 21
Wound treatment for myiasis, 204
Wristlet method of breeding lice, 303
Wyoming intermittent fever, 497
Xenopsylla cheopis, flea, 54, 56, 60, 80, 350,
351, 352, 355, 357, 360, 474, 487, 488,
495, 496
cleopatrae, flea, 354, 355
scopulifer, flea, 360, 366
Xeranesthesia, 98, 101
Xeronochelia, 98, 101
Yaws, 119, 122, 497
Yellow fever, 48, 259, 260, 262, 497
Zero ot effective temperature, 99
Zousfana, 217