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B  M   33T  blS 


A  GUIDK 

TO  THE 

ELEPHANTS 

(RECENT  AND  FOSSIL) 

EXHIBITED  IN  THE  DEPARTMENT  OF 

GEOLOGY    AND    PALAEONTOLOGY 

IN   THE 

BRITISH    MUSEUM    (NATURAL    HISTORY), 

CROMWELL    ROAD,  LONDON,  S.W.7. 


ILLUSTRATED  BY  32  TEXT-FIGURES. 


SECOND   EDITION. 


PRINTED     BY     ORDER     OF     THE     TRUSTEES 
OF     THE     BRITISH     MUSEUM. 

SOLD  AT 

THE  BRITISH  Mrskoi  (NATrRAT,  HISTORY),  CROMWKI.I.  ROAD,  S.W.  7, 

B.  QUARITCH,  LTD.,  11  GRAKTOX  STREET,  NEW  BOND  STREET,  W.I, 
DVLAU  &  Co.,  LTD.,  34-36  MARGARKT  Sri;,  RB,  W.  I, 

.    ..  _        .   ;,  ;       •  •  ,       •    ;    ',,      •      .  '  '.   :  .  \V!-.\     C«'R\!    >         1      ' 

1922. 


Sliillinq, 


A    GUIDB 


TO   THE 


ELEPHANTS 

(RECENT  AND  FOSSIL) 

EXHIBITED    IN  THE    DEPARTMENT    OF 

GEOLOGY  AND   PALAEONTOLOGY 

THE 


)  BRITISH    MUSEUM    (NATURAL    HISTORY), 

CROMWELL    ROAD,    LONDON,    S.W.  7. 


PRESENTED 


BY 


The    Trustees 


OF 


THE  BRITISH  MUSEUM 


A    GUIDE 


TO   THE 


ELEPHANTS 

(RECENT  AND  FOSSIL) 

EXHIBITED    IN   THE    DEPARTMENT    OF 

GEOLOGY   AND   PALAEONTOLOGY 


)  BRITISH    MUSEUM    (NATURAL    HISTORY), 

CROMWELL  ROAD,  LONDON,  s.w.?. 


ILLUSTRATED    BY    32    TEXT-FIGURES. 


SECOND  EDITION. 


LONDON : 

PRINTED    BY    ORDER    OF    THE    TRUSTEES 
OF     THE    BRITISH    MUSEUM. 

SOLD  AT 

THE  BRITISH  MUSEUM  (NATURAL  HISTORY),  CROMWELL  ROAD,  S.W.  7, 

AND   BY 

B.  QUARITCH,  LTD.,  11  GRAFTON  STREET,  NEW  BOND  STREET,  W.I, 
DULAU  &  Co.,  LTD.,  34-36  MARGARKT  STREET,  CAVENDISH  SQUARE,  W.  1, 
AND  THE  OXFORD  UNIVERSITY  PRESS,  AMEN  CORNER,  E.C.  4. 

1922. 
(All  rif/hts  reserved.} 


OU  IDE 


TO 


ELEPHANTS  (RECENT  AND  FOSSIL) 

IN  THE    GALLERY  OF   FOSSIL    MAMMALIA. 


THE  object  of  this  Guide-book  is  to  give  a  general  account  of 
the  Proboscidea  or  Elephants,  referring  especially  to  the  various 
stages  they  passed  through  in  the  course  of  their  evolution 
from  the  Eocene  period  to  recent  times. 

Fortunately  for  the  present  purpose,  the  British  Museum 
possesses  the  most  extensive  series  of  Proboscidea  to  be 
found  anywhere,  so  that,  except  in  very  few  instances,  readers 
can  see  in  the  S.E.  Gallery  of  Geology  the  actual  specimens, 
or,  at  any  rate,  casts  of  the  specimens,  upon  which  the  follow- 
ing descriptions  are  based,  and  can  to  some  extent  check 
the  accuracy  of  the  various  statements  for  themselves. 

Before  proceeding  to  the  description  of  the  animals,  it  may 
be  advisable  to  refer  to  the  geological  horizons  or  periods  of 
the  Earth's  history  during  which  they  existed  and  in  the  rocks 
of  which  their  fossil  remains  are  found;  for  it  is  necessary  to 
know  the  order  in  which  the  different  forms  appeared  on  the 
Earth,  just  as  in  tracing  the  pedigree  of  a  human  family 


2  ELEPHANTS. 

the  dates  of  the  documents  upon  which  it  is  founded  must 
be  known.  It  will  be  seen  from  Table  1  that  the  history 
of  the  life  of  the  Earth  falls  into  several  great  periods,  to 
which  names  have  been  given  by  geologists.  The  earliest  of 
these  is  called  the  Primary  or  Palaeozoic  Period,  and  during 
it  the  only  backboned  animals  were  fishes,  amphibians  (repre- 
sented at  the  present  time  by  newts,  frogs,  &c.),  and,  towards 
the  end,  some  reptiles.  In  the  next  great  period,  the  Secondary 
or  Mesozoic,  the  reptiles  were  of  the  greatest  importance  :  they 
were  very  numerous  and  some  were  of  gigantic  size.  They 

TABLE  1. 

f  QUATERNARY     f  RECENT. 

1  PLEISTOCENE.        > 
C^NOZOIC  <{  f  PLIOCENE. 

LTEBTIABY..  -    j    Ml°CENE- 

j  OLIGOCENE, 
I  EOCENE. 
f  CRETACEOUS. 
MESOZOIC  or  SECONDARY J  jURASsic. 

L  TRIASSIC. 
f  PERMIAN. 

CARBONIFEROUS. 
PALAEOZOIC  or  PRIMARY DEVONIAN. 

SILURIAN. 

ORDOVICIAN. 
^  CAMBRIAN. 

became  fitted  for  various  modes  of  life,  some  inhabiting  the 
land,  others  the  sea;  some  living  on  a  vegetable  diet,  others 
on  flesh.  During  this  period  also  the  birds  began  to  come  into 
existence,  and  remains  of  the  most  remarkable  of  the  early 
forms  of  birds,  Archaopteryx,  are  shown  in  table-case  13.  At 
the  same  time  the  first  of  the  warm-blooded  mammals  arose, 
though  they  were  as  yet  insignificant  in  size  and  numbers. 
The  third  period,  the  Caenozoic,  is  that  with  which  we 
are  chiefly  concerned.  During  this  the  reptiles  lost  their 
importance,  while,  on  the  other  hand,  the  mammals  took 
their  place,  becoming  extremely  numerous,  many  of  them 


GEOLOGICAL  SUCCESSION7.  O 

of  great  size  and  adapted  to  every  kind  of  life  and  food.  The 
latter  part  of  this  period,  sometimes  called  the  Quaternary, 
: extends  till  the  present  day,  and  during  it  the  mammals 
still  continue  to  be  the  prominent  backboned  animals  ;  but 
one  of  them,  man,  has  become  by  far  the  most  important 
inhabitant  of  the  world,  and,  instead  of  merely  being  slowly 
fitted  to  new  conditions  of  life,  now  to  a  large  extent  controls 
(the  conditions,  and  changes  them  to  suit  his  own  convenience. 
At  the  present  day  the  different  main  sub-divisions  of  the 
Mammalia  are,  as  a  rule,  very  distinctly  marked  off  from  one 

Fig.  1. 


Upper  and  lower  dentition  of  pig,  showing  the  presence  of  the  full  set  of 
44  teeth  and  the  low-crowned  bunodont  cheek-teeth  adapted  for  a  soft, 
mainly  vegetable  diet,  c.,  canine ;  «'.,  incisors;  m.,  molars;  pm.,  pre- 
molars. 

another.  For  instance,  the  Carnivora  (flesh-eaters,  e.  g.}  tiger, 
bear)  are  now  widely  different  from  the  Ungulata  (hoofed- 
animals,  e.  y.y  horse  and  ox),  each  of  these  groups  being  fitted 
for  some  special  manner  of  life,  and  particularly  for  living  on 
some  special  kind  of  food.  Thus,  the  principal  character  of 
most  of  the  Carnivora  is  the  possession  of  sharp  claws  and 
teeth  for  killing  and  devouring  other  animals;  while,  on  the 
other  hand,  the  vegetarian  Ungulata  have  teeth  fitted  for 

B2 


4  ELEPHANTS. 

grinding  vegetable  matter  and  feet  adapted  solely  for  moving 
from  place  to  place  in  search  of  pasturage.  If,  however,  we 
trace  back  through  the  earlier  periods  of  the  Earth's  Geological 
History  the  extinct  animals  from  which  these  quite  distinct 
modern  groups  are  descended,  we  find  that,  in  nearly  all  cases 
in  which  these  earlier  fossil  forms  are  well  known,  there  is  a 
tendency  for  them  to  become  more  and  more  alike.  In  the 
early  Eocene,  indeed  (see  Table  1,  p.  2),  the  Garni vora  and 
Ungulata  are  not  always  to  be  distinguished  from  one  another 

Fig.  2. 


Skull  and  mandible  of  Striped  Hyaena,  showing  the  sharp  cutting  cheek- 
teeth adapted  for  a  flesh  diet.     Lettering  as  in  fig.  1. 

with  certainty,  so  that  the  animals  from  which  they  and  some 
other  mammals  have  descended  may  be  placed  in  a  single 
group.  Nearly  all  these  early  mammals  have  certain  characters 
in  common:  thus  in  most  there  are  five  toes  on  each  foot  and 
forty-four  comparatively  simply  constructed  teeth.  Characters 
such  as  these  are  called  "  primitive/'  and  when  as  time  goes 
on  they  become  gradually  changed  in  different  ways  and 
adapted  for  particular  purposes,  they  are  said  to  be  more 
"specialised."  Thus  in  the  horse  the  foot  (fig.  3)  is  extremely 
specialised,  in  that  it  has  only  a  single  complete  toe  instead  of 


SPECIALISATION. 


the  primitive  number,  five  :  its  limbs  are  specially  fitted  for 
swift  movement  over  bard  ground.  To  take  another  instance, 
the  teeth  of  the  tiger  are  said  to  be  highly  "  specialised/' 
because  there  are  only  thirty  of  the  original  forty-four,  and 
these  have  become  specially  adapted  for  seizing  living  prey  and 
cutting  and  tearing  its  flesh.  It  must  be  added  that  all  the 
characters  of  a  group  of  animals  do  not  necessarily  become 
specialised,  but  that  some  may  remain  in  the  primitive  condi- 
tion. Thus  man,  in  some  ways  the  most  highly  specialised  of 
mammals,  still  retains  the  primitive  number  of  five  digits  on 
both  limbs. 


Fig.  3. 


ii 


Diagram  showing  the  gradual  loss  of  toes  on  the  fore  foot  (a)  and  increase 
of  complexity  in  the  grinding  teeth  (b)  of  successive  horse-like  Ungulata 
from  Europe,  namely  Hyracotherinm  (Eocene)  4,  Anchitherium  (Mio- 
cene) :3,  HippaHon  (Pliocene)  2,  Equus  (Pleistocene  and  Recent)  1. 


In  order  to  trace  back  a  modern  specialised  group  of  mammals 
to  its  early  primitive  ancestors,  a  long  series  of  fossil  remains 
from  the  successive  geological  periods  is  necessary.  Unfor- 
tunately, in  many  cases  these  fossils  have  yet  to  be  found,  but 
every  year  further  discoveries  are  made  and  gaps  of  more  or 
less  importance  are  filled  up.  The  series  of  changes  undergone 
by  a  group  of  mammals  is  perhaps  best  known  in  the  horse 


6  ELEPHANTS. 

family  *,  but  recent  discoveries  of  remains  of  early  forms  of 
the  elephant  group  in  the  Eocene  and  Oligocene  beds  of  the 
Libyan  Desert  in  Egypt  have  made  it  possible  to  trace 
the  history  of  the  elephants  also  with  considerable  accuracy 
and  completeness. 

In  the  fossil  mammals  it  is  the  teeth  that  are  of  the  greatest 
importance  in  settling  the  relationships  of  different  species  to 
one  another,  and  in  forming  an  opinion  as  to  their  food  and 
probable  manner  of  life. 

The  reason  for  the  importance  of  fossil  teeth  is  that,  while  in 
many  ways  they  are  very  conservative,  long  retaining  traces  of 
the  earlier  forms  from  which  they  have  originated,  nevertheless 
they  readily  undergo  change  in  accordance  with  the  kind  of 
food  they  are  called  upon  to  seize  and  masticate.  Moreover, 
from  their  hardness  they  are  more  frequently  preserved  than 
most  other  parts  of  the  skeleton.  It  will  be  well,  therefore, 
before  considering  the  teeth  of  the  Proboscidea  to  give  a  short 
account  of  mammalian  teeth  in  general,  so  that  the  later 
descriptions  may  be  understood. 

The  tooth  of  a  mammal  (see  "Mammalia"  in  Index  collection 
in  Central  Hall,  Bay  I.)  consists  of  a  root  or  roots  embedded  in 
a  socket  in  the  jaw,  and  a  crown  which  is  exposed  and  is 
adapted  for  the  work  it  has  to  perform.  In  a  section  of  a  tooth 
(fig.  4)  it  is  seen  that  the  greater  part  is  composed  of  a  hard 
material  called  dentine,  and  that  the  crown  of  the  tooth  is  usually 
covered  with  a  still  harder  substance  known  as  enamel,  while 
in  some  cases  the  root,  and  in  others  (usually  the  more  com- 
plicated forms)  both  root  and  crown,  may  be  coated  with  a  softer 
bony  matter,  called  cement.  The  form  of  the  crown  differs 
enormously  in  different  animals  and  in  different  parts  of  the 
mouth  :  it  may  be  a  simple  cone  like  the  canine  or  dog-tooth, 
or  it  may  form  a  large  complicated  grinding  surface  as  in  the 
back  teeth  of  the  horse.  The  teeth  are  usually  divided  into 
different  series  according  to  their  particular  position  in  the 
mouth  and  the  duties  they  have  to  perform  (see  figs.  1  &  2). 
The  front  teeth  implanted  in  the  anterior  part  of  the  jaw  are 

*  Casts  of  specimens  showing  the  gradual  "  specialisation  "  of  the  teeth 
and  feet  in  the  horses  are  shown  in  a  case  in  the  North  Hall.  See  also 
Pier-case  10  and  Table-case  5  in  Gallery  of  Fossil  Mammals. 


CHARACTERS  OF  TEETH. 


7 


mainly  concerned  in  grasping  and  biting  off  the  food:  these  are 
called  incisors.  In  mammals  which,  like  the  pig  (fig.  1),  possess 
the  primitive  number  of  teeth,  there  are  three  of  these  on  either 
side  in  both  upper  and  lower  jaws.  Behind  these  come  the 

Fig.  4. 


Diagrammatic  section  of  various  teeth, 

I.  Section  of  tusk  of  elephant,  a  permanently  growing  tooth.     II.  Section 
of  a  young  human  incisor  still  growing,  the  root  not  yet  fully  formed. 

III.  Section  of  human  incisor  fully  formed,  the  root  being  complete. 

IV.  Section  of  human  molar  showing  the  low-crowned  (brachyodont) 
condition,  the  cusps  being  rounded  tubercles  (bunodont).     V.  Section  of 
the  molar  of  an  ox,  showing  the  high  (hypsodont)  complexly  folded 
crown.       In    the    figures   the   enamel    is  black,  the    pulp    white,  the 
dentine  represented  by  horizontal  lines,  the  cement  by  dots. 

canines,  one  on  each  side  above  and  below ;  these  are  generally 
more  or  less  pointed  teeth,  serving  chiefly  for  fighting  or  defence. 
Behind  these  again  are  the  cheek-teeth,  which  have  to  do  mainly 


8  ELEPHANTS. 

with  the  breaking  up  of  the  food  before  it  is  swallowed  :  in  the 
complete  dentition  there  are  seven  of  these  on  either  side  in  both 
jaws  and  they  are  divided  into  two  groups,  (1)  four  premolars 
in  front  and  (2)  three  molars  behind:  the  premolars,,  or  at 
least  those  posteriorly,  replace  the  milk-molars  of  the  young 
animal,  while  the  molars  have  no  predecessors.  It  is  in  the 
premolars  and  molars  that  the  greatest  variety  of  structure  is 
found,  as  might  be  expected,  because  it  is  these  teeth  that 
are  most  affected  by  the  nature  of  the  food.  Teeth  suitable  for 
cutting  up  flesh  would  be  quite  unfitted  for  grinding  hard  vege- 
table matter,  and  consequently  in  animals  feeding  on  soft  material 
the  teeth  differ  widely  from  those  in  which  the  food  is  hard  and 
requires  much  mastication.  In  the  former  the  crowns  of  the 
teeth  are  low  and  their  cusps  or  tubercles  are  either  sharp  and 
cutting  in  the  case  of  flesh-feeders  (e.  g.,  lions  and  tigers)  or 
rounded  (bunodont)  in  the  case  of  animals  feeding  on  a  soft 
vegetable  or  mixed  diet  (e.g.,  pigs  and  bears) .  Teeth  of  this  low- 
crowned  sort  are  called  brachyodont  (fig.  4,  IV).  In  the  case  of 
animals  whose  food  is  hard  and  requires  much  grinding,  the 
wear  of  the  teeth  is  so  great  that  simply-constructed  low  crowns 
would  be  quickly  worn  out,  and  it  must  be  remembered  that 
the  length  of  an  animal's  life  is  largely  dependent  on  the  time 
during  which  its  teeth  remain  in  good  working  order.  To  meet 
the  increased  wear  the  crown  of  the  tooth  becomes  higher  and 
moves  up  in  the  gum  as  wear  takes  place,  sometimes  through- 
out the  animal's  life  or  only  for  a  time ;  teeth  of  this  high- 
crowned  sort  are  called  hypsodont  (fig.  4,  V) .  With  this  increase 
in  height  of  the  crown  there  is  generally  greater  complication, 
resulting  from  the  infolding  of  the  enamel  in  various  ways  and 
the  development  of  cement  on  the  crown  as  well  as  on  the  roots. 
One  example  of  this  gradual  increase  of  height  and  complication 
is  about  to  be  described  in  the  case  of  the  elephants ;  another 
extremely  good  instance  is  found  in  the  gradual  evolution  of 
the  teeth  in  the  horses,  as  excellently  illustrated  in  the  case  in 
the  North  Hall  and  in  Table-case  5  (see  fig.  3). 

From  the  above  account  it  will  be  seen  that  when  the  full 
number  of  teeth  is  present  there  are  three  incisors,  one  canine, 
four  premolars,  and  three  molars  on  each  side  in  the  upper  jaw, 


DENTITION. 


and  the  same  in  the  lower  jaw.  This  is  usually  expressed  shortly 
by  a  formula,  thus  :— I.f,  C.  \,  Pm.*,  M.§  =  ~,  the  letters 
denoting  the  kind  of  teeth,  the  upper  numbers  the  number 
of  each  kind  on  one  side  in  the  upper  jaw,  the  lower 
numbers  those  in  the  lower  jaw,  so  that  in  the  example  above 
given  there  would  be  eleven  teeth  on  each  side  in  both  the 
upper  and  lower  jaws,  or  forty-four  in  all.  As  has  already  been 
mentioned,  a  greater  or  less  number  of  these  teeth  may  be 
wanting  in  different  animals  and  the  formula  will  differ 
accordingly:  thus  in  man  it  is  1. 1,  C.},  Pm.jj,  M.y  =  g  or 
thirty-two  in  all.  In  the  cat  it  is  1. 1,  C.  ~,  Pm.|,  M.  \  =  * 
or  thirty  in  all. 

Among  living  mammals  the  elephants  are  perhaps  the  most 
remarkable.  Not  only  do  they  exceed  in  size  all  other  living 
land-animals,  but  they  are  further  distinguished  by  the  possession 
of  a  mobile  trunk  or  proboscis,  which  is  at  once  a  sensitive 
organ  of  touch  and  a  most  efficient  means  of  grasping  objects, 
both  large  and  small.  Furthermore,  the  structure  of  their  teeth 
reaches  a  degree  of  complication  not  to  be  found  in  any  other 
animals.  At  the  same  time,  though  in  many  respects  so  peculiar, 
in  others  they  retain  primitive  characters  that  have  been  lost  in 
most  of  the  other  Ungulata,  with  which  they  are  usually  classed. 
The  most  notable  of  these  primitive  characters  is  the  presence 
of  the  original  five  toes  on  each  foot,'  while  in  most  hoofed- 
animals  the  feet  have  become  "  specialised  "  by  the  loss  of  one 
or  more  of  the  digits. 

It  is  now  proposed  to  describe  some  of  the  principal  stages 
by  which  the  elephants  gradually  came  to  be  what  they  are  at 
the  present  day,  and  to  show  that  the  earliest-known  forms 
were  much  like  other  primitive  hoofed-animals,  a  condition 
to  which  the  pigs  and  tapirs  among  living  mammals  perhaps 
most  nearly  approach.  It  will  be  shown  that  the  earliest- 
known  animal  belonging  to  the  Proboscidea  or  elephants  was, 
in  fact,  not  unlike  a  large  pig  (see  fig.  8),  though  in  some 
respects  an  even  more  primitive  creature.  From  this  beginning 
we  can  trace  a  gradual  increase  in  size  in  the  later  forms,  a 
gradual  development  of  the  trunk  or  proboscis,  first  as  the 


10  ELEPHANTS. 

upper  part  of  a  long  snout  supported  by  the  elongated  lower 
jaw,  afterwards  as  the  familiar  movable  organ  so  characteristic 
of  the  modern  elephants.  We  can  also  observe  the  gradual 
increase  in  the  size  and  degree  of  complication  of  the  grinding- 
teeth,  accompanied  by  the  complete  loss  of  many  of  the  teeth 
found  in  the  earlier  forms.  Finally,  we  have  materials  for 
discussing  the  probable  relationship  of  the  elephants  to  some 
other  groups  of  animals. 

The  table  on  page  11  shows  what  are  the  chief  forms 
of  Proboscideans  living  at  the  different  periods  and  their 
distribution  over  the  world.  It  will  be  seen  that  the  earliest 
mammal  which  can  be  delinitely  called  a  Proboscidean  is 
Moeritherium,  a  small  tapir-like  creature  from  the  Upper 
Eocene  beds  of  the  Fayum  district  of  Egypt.  This  genus 
existed  also  in  the  Lower  Oligocene  of  the  same  region,  but 
was  then  accompanied  by  a  larger  and  much  more  elephant-like 
animal,  Palaomastodon.  At  this  time  Africa  was  cut  off  from 
the  rest  of  the  world  to  the  north  by  a  broad  and  deep  sea  which 
extended  from  the  Atlantic  to  the  Pacific  by  way  of  Northern 
India  and  Southern  China,  and  the  separation  of  Africa  pre- 
vented these  early  forms  of  elephant  from  wandering  into  other 
regions  till  after  the  Lower  Oligocene.  After  PalfPomas- 
todon  there  is  a  large  gap  in  the  series,  no  fossil  Proboscidea 
having  yet  been  found  in  the  Upper  Oligocene,  though  no  doubt 
their  remains  will  be  discovered  somewhere  in  the  fresh- water 
deposits  of  that  age  in  Egypt.  Hitherto  no  Proboscidean 
bones  and  teeth  have  been  met  with  again  till  the  Miocene,  but 
in  rocks  of  that  period  they  are  found  abundantly,  not  only  in 
Egypt,  but  in  Europe,  Asia,  and  North  America.  It  is  there- 
fore clear  that  during  the  long  lapse  of  time  after  the  Eocene, 
the  deep  sea  above  referred  to  must  to  some  extent  have  been 
replaced  by  land,  over  which  the  early  elephants  could  spread 
outwards  from  their  home  in  Africa.  The  vast  changes  in  the 
distribution  of  land  and  water  that  took  place  in  this  region 
will  be  apparent  when  it  is  understood  that  rocks  crowded  with 
the  shells  that  lived  at  the  bottom  of  this  ancient  sea  are  to-day 
found  thousands  of  feet  above  sea-level  in  India  and  elsewhere. 

From  the  Miocene  period  onwards  we  meet  with  elephant-like 


GEOLOGICAL  SUCCESSION. 


il 


H 


12  ELEPHANTS. 

animals  in  great  variety  all  over  the  Northern  Hemisphere, 
"wherever  suitable  deposits  for  the  preservation  of  their  remains 
occur.  At  the  end  of  the  Pliocene  period  the  group  also 
spread  into  South  America,  but  at  the  present  day  it  is  totally 
wanting  in  the  whole  Western  Hemisphere. 

During  the  later  Miocene  and  Pliocene  periods  the  head- 
quarters of  these  animals  seem  to  have  been  in  India,  for  it  is 
there  that  we  meet  with  the  greatest  number  and  variety  of 
forms,  showing  all  grades  of  structure  between  the  Miocene 
types  above  referred  to  and  elephants  almost  like  those  now 
existing.  From  the  end  of  the  Pliocene  to  the  beginning  o'f 
the  Quaternary  Period  may  be  regarded  as  the  time  during 
which  the  elephants  reached  their  most  flourishing  condition, 
both  in  the  number  of  kinds  that  existed  and  in  the  wide 
range  over  which  they  were  spread.  After  this  a  gradual 
decline  in  the  group  took  place,  till,  at  the  present  day,  it  is 
represented  by  two  species  only,  the  African  elephant  confined  to 
Tropical  Africa,  and  the  Indian  elephant  found  in  India,  Ceylon, 
Burma,  the  Malay  Peninsula,  and  some  of  the  neighbouring 
islands.  But  for  restrictions  placed  upon  their  slaughter, 
even  these  la-t  remnants  of  one  -of  the  oldest,  and  in  many 
ways  the  most  remarkable,  groups  of  mammals  would  soon 
disappear,  just  as  has  happened,  for  instance,  in  the  case  of 
the  great  ground-sloths  of  South  America,  the  giant  lemurs 
of  Madagascar,  and  the  giant  marsupials  such  as  Diprotodon 
in  Australia. 

A  more  detailed  account  of  the  changes  that  the  Proboscidea 
have  passed  through  will  now  be  given,  the  following  animals 
being  selected  for  description  as  representing  six  of  the  most 
important  of  the  successive  stages  at  present  known  : — 

1.  Moeritherium,  Upper  Eocene  and  Lower  Oligocene. 

2.  PaltPomastodon,  Lower  Oligocene. 

3.  Tetrabelodon  angustidens ,  Miocene. 

4.  ,,  longirostris,  Lower  Pliocene. 

5.  Stegodon  insigms,  Pliocene. 

6.  Elephas,  Pliocene.  Pleistocene,  and  Recent. 

Some  reference  will  also  be  made  to  other  types,  such  as 
Dinotherium  and  Mastodon. 


ANCESTRY  OF   ELEPHANTS. 

1       6. 


13 


Recent 
Pleistocene 
Upper  Plioce fie 


ELEPHAS 
(shortchin) 


Lower  Pliocene      TETRABELODON 

[LONGIROSTRIS  STAGE 
Uflfier  Miocene         (shortening  chin) 


Middle  Miocene     TETRABELODON 

[ANGUSTIDENS  STAGE] 
Lower  Niocene          (longchin) 


UnnerOligocene        ™ 9™*™  from  Africa 
into  Lurone  - 


Lower  Olyocene      PAL  AEO  MASTODON 

(lengthening  chin) 
ditto    ditto     \ 

n.  [    MOERITHERIUM 

Upper  Eocene  y      (short  cflm) 

Lower  Eocene  • 

Diagram  showing-  some  stages  in  the  gradual  increase  in  size,  and  alteration 
in  form,  of  the  skull  and  mandible  occurring  in  the  Proboscidea  from 
the  Eocene  to  the  present  day. 


14  ELEPHANTS. 


MOERITHERIUM. 

Moeritherium  (figs.  6,  7,8)  (Wall-case  43  ;  Table-case  24)  was 
an  animal  about  the  size  of  the  tapir,  which  it  must  have 
much  resembled  in  general  appearance.  It  was  common  in  the 
region  that  is  now  known  as  the  Fayum  in  Lower  Egypt, 
where  its  fossil  remains  occur  in  considerable  quantities  in 
the  Upper  Eocene  beds,  intermingled  with  bones  of  toothed 
whales  (Zeuglodori),  sea-cows  (Eosiren),  marine  turtles  (Pse- 
phophorus  and  Thalassochelys),  and  snakes  (Pterosphenus) ,  as 
well  as  skeletons  of  fishes.  From  this  mixture  of  land  and 
aquatic  animals  it  may  be  concluded  that  Moeritherium  lived 
near  the  shore,  probably  in  swamps  at  the  mouth  of  a  great 
river,  where  the  remains  of  both  marine  and  of  drowned  land- 
animals  would  be  mingled  and  entombed  together  in  the  muds 
and  clays,  which  accumulated  in  the  estuary  and  now  make  up 
much  of  the  strata  found  in  this  locality.  In  the  Lower 
Oligocene  beds,  overlying  those  just  described,  remains  of 
Moeritherium  are  also  found;  here,  however,  there  is  no  inter- 
mingling of  marine  animals,  but  instead  we  find  remains  of 
many  remarkable  land-mammals,  crocodiles,  and  immense 
quantities  of  trunks  of  fossil  trees  embedded  in  the  sands  and 
gravels  of  a  great  river.  Probably  both  the  animals  and  the 
tree-trunks  were  swept  away  by  floods,  their  remains  piled  up 
in  shallows  and  places  where  the  current  was  slack,  and  buried 
in  the  mud  and  sand  carried  down  by  the  stream. 

The  skull  of  Moeritherium  (see  fig.  6)  differs  in  no  very 
marked  manner  from  that  of  other  primitive  hoofed-animals, 
and  shows  scarcely  any  trace  of  the  peculiarities  of  the 
skulls  of  the  later  Proboscidea.  The  most  important  feature 
is  the  large  nasal  opening  not  quite  at  the  end  of  the 
snout,  the  nasal  bones  being  short ;  this  indicates  that  probably 
there  was  already  a  short  proboscis,  something  like  that  of  the 
tapir.  Another  interesting  point  is  that  some  of  the  bones  at 
the  back  of  the  skull  are  thickened  and  contain  air-chambers ; 
in  the  later  elephants  this  development  of  air-cells  is  carried  to 
such  an  extent  that  the  whole  form  of  the  skull,  particularly  the 


MOKKITIIKKIUM.  15 

.posterior  portion,  is  entirely  altered  by  it  (see  the  broken 
skull  of  the  Indian  elephant  in  Gallery).  The  reason  for 
this  swelling  of  the  bones  is  that,  as  the  head  becomes 
heavier,  owing  in  great  part  to  the  development  of  the  trunk 
and  tusks,  a'  larger  surface  for  the  attachment  of  the  muscles 
which  support  the  head  is  necessary,  and  even  in  the  small 
Eocene  Moeritherium  change  in  this  direction  had  begun. 

In  Moeritherium  the  dental  formula  (see  p.  9)  is  I.  ^,  C,  J, 
Pm.  |,  M.  |=£  or  thirty-six  in  all  (figs.  5  &  7).  From  the 
formula  it  will  be  seen  that  in  the  upper  jaw  only  one  premolar 
is  wanting  to  complete  the  primitive  number,  while  in  the 

Fig.  6. 


Skull  and  lower  jaw  of  Moeritherium  from  the  Upper  Eocene  of  the  Fay  urn, 

Egypt.     4  nat.  size. 

ant.orb.,  antorbital  foramen ;  c.,  canine  ;  e.r.oc.,  exoccipital ;  />'., 
frontal;  i.  1-3,  incisors;  ju.,  jugal;  m.  1-3,  molars;  mx.,  maxilla; 
n.,  nasal;  p.a.,  parietal;  par.,  paroccipital ;  pm.  2-4,  premolars; 
p.mx.,  premaxilla;  pt.,  post-tympanic  process  of  squamosal ;  s.oc.,  supra- 
occipital  ;  sq.,  squamosal. 

lower  jaw  an  incisor  and  the  canine  are  missing  on  each  side 
in  addition  to  one  premolar. 

Of  the  upper  incisors  the  second  pair  (i.  2)  are  greatly 
enlarged  and  form  strong  downwardly  directed  tusks,  the 
beginning  of  the  great  tusks  so  characteristic  of  the  later 
elephants.  The  canine  (c.)  seems  to  have  been  quite  small  and 
unimportant,  being  on  the  way  to  disappearance.  The  pre- 
molars (pm.)  are  separated  from  the  canine  by  a  short  interval, 
and,  as  already  mentioned,  the  anterior  one  of  the  full  denti- 
tion is  wanting.  The  remaining  premolars  are  all  simpler  in 


16 


ELEPHANTS. 


structure  than  the  molars  behind  them,  and  consist  of  three  main 
cusps  only,  the  two  front  cusps  being  arranged  in  a  transverse 
line  in  the  third  and  fourth  premolars.  These  teeth  are  preceded 
by  milk-teeth  which  they  displace  from  above  as  in  the  ordinary 
mammals  ;  in  the  later  elephants  we  shall  see  that  this  usual 
replacement  of  milk-teeth  by  premolars  is  gradually  lost. 

Fig.  7. 


Upper  and  lower  teeth  of  Moeritherium. 

A.  Upper  teeth.  B.  PremaxiHa,  large  tusk-like  second  incisor.  C.  Man- 
dible from  other  side,  c.,  socket  of  canine  ;  i.  1-3,  incisors ;  m.  1-3, 
molars  ;  pm.  2-4,  premolars.  \  nat.  size. 

The  molars  (fig.  7.  A,  m.)  are  the  most  interesting  and  im- 
portant of  the  teeth,  because  it  is  in  them  that  the  most  nearly 
complete  series  of  gradually  more  and  more  complicated  forms 
can  be  traced.  In  Moeritherium  the  crown  of  each  upper  molar  is 
composed  of  two  transversely  arranged  pairs  of  knobs,  giving 
rise  to  a  pair  of  transverse  crests  ;  there  are  also  in  many  cases 
small  posterior  knobs — the  first  trace  of  the  tendency  to  increase 
the  number  of  transverse  crests  by  additions  to  the  back 
of  the  tooth,  which  is  characteristic  of  the  whole  group. 


MOERITHERIUM. 


17 


In  the  lower  jaw  (figs.  6  &  7  C)  the  middle  incisors  (i  1)  are 
small,  the  second  pair  (/  2)  large  and  tusk-like ;  both  are 
directed  forward  and  their  upper  surface  continues  forward  the 


oo 


surface  of  the  spout-like  anterior  portion  of  the  jaw.  The  third 
incisors,  the  canine,  and  the  first  premolar  of  the  full  dentition 
are  wanting.  The  remaining  three  premolars  (pm.),  which  re- 
place milk-molars,  are  simpler  than  the  molars,  and  only  in  the 

c 


18  ELEPHANTS. 

third  ami  fourth  is  there  any  '.arrangement  of  the  anterior 
cusps  to  form  a  transverse  ridge.  The  first  and  second  molars 
(fig.  7  C),  like  those  of  the  upper  jaw,  consist  of  two  transversely- 
arranged  pairs  of  knobs  and  a  posterior  knob  which  is  larger 
than  in  the  upper  teeth.  The  last  lower  molar  (fig.  10  A)  has 
a  third  ridge  forming  a  sort  of  heel  or  talon,  as  it  is  called  ;  this 
tooth,  though  much  smaller,  is  remarkably  similar  to  the  molars 
of  some  of  the  earlier  forms  oE  Mastodon. 

The  skeleton  of  Moeritherium  is  not  well  known,  but  some  of 
the  most  important  points  in  its  structure  are: — (1)  the  neck 
is  proportionated  longer  than  in  the  later  elephants  in  which  it 
is  much  shortened,  (2)  the  hip-bones  are  narrow,  while  in  the 
later  forms,  owing  to  the  great  increase  in  size  and  weight,  they 
are  much  expanded.  The  humerus  also  is  rather  different, 
particularly  at  its  lower  end,  the  great  supinator  ridge,  so 
characteristic  of  the  larger  Proboscidea,  being  scarcely  developed. 
On  the  other  hand,  the  thigh -bone  is  extremely  like  that  of  a 
very  small  elephant. 

To  sum  up  the  primitive  characters  of  Moeritherium  :— 

1 .  The  skull  differs  little  from  that  of  an  ordinary  ungulate. 

2.  There  is  a  full  set  of  three  pairs  of  incisors  in  the  upper, 

and  only  one  pair  wanting  in  the  lower  jaw. 

3.  There  is  a  canine  on  each  side  in  the  upper  jaw. 

4.  There  are  three  premolars  in  the  upper  and  lower  jaws 

replacing  milk-molars. 

5.  The  molars  have  only  two  transverse  ridges  and  a  small 

hind  lobe  ;  each  transverse  ridge  is  composed  of  two 
distinct  cusps ;  the  third  lower  molar  has  also  a  heel 
or  talon. 

Some  of  the  more  important  of  the  Proboscidean  characters 
are  : — 

1.  The  large  size  of  the  external  nasal  opening,  its  some- 

what backward  situation,  and  the,  small  size  of  the 
nasal  bones. 

2.  The  commencement  of  the  development  of  air-cells  in 

the  bones  of  the  back  of  the  skull. 


PALjEOMASTODON.  19 

3.  The  enlargement  of  the  second  incisors  in  both  jaws  to 

form  tusks. 

4.  The  transversely  ridged  character  of  the  molars. 

5.  The  spout-like  anterior  portion  of  the  lower  jaw. 

All  these  characters  become  much  more  marked  in  the  next 
stage,  which  is  represented  by  Palaomastodon  from  the  Upper 
Eocene  of  JEgypt. 

PAL^OMASTODON. 

The  genus  Paiteomastodon  (figs.  9-11, 13  A)  (Wall-case  43  ; 
Table -case  24)  is  represented  by  species  varying  in  size  from 
an  animal  little  larger  than  Moeritherium  to  one  nearly  as 
large  as  a  small  elephant,  so  that  in  size  alone  there  is  a  great 
advance  in  the  direction  of  the  modern  elephants.  In  the 
structure  of  the  skull  and  teeth,  as  well  as  in  the  rest  of  the 
skeleton,  so  far  as  known,  the  advance  is  likewise  very  striking. 

In  the  skull  (see  fig.  9)  the  opening  of  the  nostril  (nar.)  has 

Fig.  9. 


Skull  aud  lower  jaw  of  Palcco mastodon,  showing  the  elongated  chin  with 
a  pair  .of  terminal  incisors  (Li.),  from  the  Lower  Oligocene  of  the 
Fayum,  Egypt.  T^  nat.  size. 

nar.,  position  of  opening  of  nose  ;  u.i.,  upper  second  i.icisoi*  or  tusk. 

shifted  far  back  from  near  the  end  of  the  snout,  though  it  is 
still  in  front  of  the  orbit  of  the  eye.  The  nasal  bones  are  still 
shorter  and  smaller  than  in  Moeritherium.  At  the  back  of  the 
-skull  the  development  of  air-cells  in  some  of  the  bones  has 


20 


ELEPHANTS. 


enormously  increased,  but  lias  not  yet  invaded  the  root'  of  the 
skull,  so  that  the  sides  are  only  separated  by  a  sharp  median 
crest.  The  posterior  surface  of  the  skull  slopes  forward  above 
the  condyles,  and  there  is  a  deep  pit  in  the  middle  line  for  the 
attachment  of  the  muscles  necessary  to  support  the  increasingly 
heavy  head. 

Of  the  incisor  teeth  in  the  upper  jaw  only  the  second  pair 
now  remains,  and  these  have  been  still  further  enlarged,  forming- 
Fig.  10. 


Posterior  lower  molars  (m2,ma)  of  (A)  Moerithenum^  (B)  Palvomastodon, 
showing-  the  increase  in  the  number  of  ridges  of  Palceomastodon. 
I  nat.  size. 

downwardly  directed,  curved,  somewhat  flattened  tusks  with  a 
broad  band  of  enamel  along  their  outer  sides  only.  The 
canine  has  disappeared,  but  there  are  still  three  premolars 
replacing  milk-molars.  The  anterior  premolar  is  a  simple 
cone,  while  the  crown  of  the  posterior  one  consists  of  two 


PAL^OMASTODON.  21 

transverse  ridges,  these  teeth  being  subjected  to  two  distinct 
influences,  namely,  the  tendency  to  the  reduction  in  the 
front  of  the  series  and  the  tendency  to  become  more  like  the 
molars  at  the  back.  The  three  molars  themselves  show  a 
distinct  advance,  the  crown  of  each  consisting  of  three  transverse 
ridges,  each  ridge  composed  primarily  of  t\\  o  main  cusps  which 
may,  however,  show  small  traces  of  sub-division  into  secondary 
cusps. 

The  mandible  (figs.  9  &  13  A)  differs  from  that  of  Moeri- 
therium  in  the  much  greater  prolongation  of  the  spout-like 
anterior  portion ;  this  now  projects  a  considerable  distance 
in  front  of  the  skull  and  is  prolonged  still  further  forward  by 
the  single  remaining  (second)  pair  of  incisor  teeth,  which  meet 
in  the  middle  line  and  from  a  sort  of  shovel-shaped  extension ; 
the  edges  are  worn  both  011  the  upper  and  lower  surface,  so  that 
these  teeth  were  probably  used  for  grubbing  about  in  the  ground 
to  procure  food,  and  the  upper  surface  must  have  been  further 
worn  by  working  against  the  lower  surface  of  the  trunk  or 
elongated  upper  lip. 

There  are  only  two  premolars  in  the  lower  jaw,  the  anterior 
of  the  three  milk-molars  (figs.  9  &  13  A)  falling  out  without 
being  replaced  from  below  ;  the  molars  are  three  in  number, 
the  two  anterior  with  three  transverse  ridges,  the  third  some- 
times having  in  addition  a  small  heel  (fig.  10  B).  It  should  be 
noticed  that  in  the  full-grown  animal  all  the  molars  and  pre- 
molars are  in  position  and  use  at  the  same  time  ;  it  will  be  seen 
that  in  the  later  forms  of  elephant-ancestors  this  is  not  so. 

The  skeleton,  so  far  as  known,  is  almost  exactly  like  that  of 
a  small  elephant,  the  only  important  differences  being  that  the 
neck  is  longer  and  the  limbs  most  likely  less  massive.  The  animal, 
as  a  whole  (fig.  11),  must  have  been  very  like  a  small  elephant, 
but  would  be  distinguishable  by  the  longer  head  and  neck,  and 
by  the  fact  that  instead  of  possessing  a  flexible  trunk  it  had  a 
long  snout,  the  lower  portion  consisting  of  the  elongated  lower 
jaw,,  the  upper  without  bony  support  and  probably  extending 
beyond  the  lower ;  the  projecting  portion  most  likely  was  more 
or  less  flexible  and  capable  of  seizing  objects,  and  was  the 
beginning  of  the  prehensile  trunk. 


22 


ELEPHANTS. 


TETRABELODON.  23 

The  chief  steps  taken  by  Palaomastodon  in  advance  of  Moeri- 
therium  towards  greater  likeness  to  the  later  elephants  are  : — 

1.  Considerable  increase  in  size. 

2.  Lengthening  of  the  snout,  as  shown  by  the  mandible. 

3.  Loss  of  canines  and  all  the  incisors  except  the  second 

pair  in  both  jaws. 

4.  Three-ridged  molars. 

5.  Greater  development  of  air-cells  at  back  of  skull. 

6.  Shifting  further  back  of  the  nose-opening  and  smaller 

size  of  the  nasal  bones. 

7.  Greater  similarity  of  the  bones  of  the  skeleton  to  those 

of  ordinary  elephants. 

TETRABELODON. 

The  next  stage  is  found  in  Tetrabelodon  angustidens  (figs.  12- 
14,  16)  (Pier-cases  41,  42;    Table-case  23),  from  the  Lower 

Fig.  12. 


Skull  and  mandible  of  Tetrabelodon  angustidem,  showing  the  greatly  elongated 
chin  with  a  pair  of  terminal  cutting  incisors  (/.£.),  from  the  Lower  and 
Middle  Miocene,  France.  ^  nat.  size. 

nar.f  position  of  opening  of  nose  ;  u.i.j  upper  incisors. 

Miocene  of  Northern  Africa,  Europe,  and  probably  Asia.     This 
animal  is  as    large  as  a  medium-sized  elephant,  and  its  teeth  and 


24  ELEPHANTS. 

skull  are  much  more  elephant-like  than  in  Palteomastodon. 
Thus  the  nostrils  have  shifted  still  further  back,  and  the  great 
development  of  air-cells  in  the  bones  at  the  back  of  the  skull 
has  led  to  the  disappearance  of  the  ridge  along  the  middle 
of  the  roof,  which  is  now  flat.  Further,  the  upper  tusks, 
which  were  quite  small  and  flattened  in  Palaomastodon,  are 
now  large  and  round,  and  differ  from  those  of  a  modern 
elephant  only  in  curving  downward  instead  of  upward,  and  in 
having  a  band  of  enamel  along  the  outer  side  relatively  much 

Fig.  13. 


jimi 


sym. 


rn.2 


Lower  milk-dentition  of  (A)  Palcsomastodon,  (B)  Tetrabelodon  anyustidens. 
Showing  some  of  the  milk-teeth  in  situ,  with  the  germs  of  replacing 
premolars.  The  germs  of  the  2nd  molars  are  shown  at  the  back  of  the 
jaw.  About  I  nat.  size. 

i.,  incisor;  m.  1-2,  permanent  molars  ;  mm.  3-4,  third  and  fourth 
milk-molars  ;  mm.,  socket  of  second  milk-molar  ;  pin.  3-4,  premolars  ; 
sym.,  symphysis  of  mandible. 

narrower  than  in  Palcsomastodon,  in  which  nearly  the  whole 
outer  face  of  the  tooth  is  enamel-clad.  As  the  tusks  increase  in 
size,  the  dentine  of  which  they  are  composed  acquires  a  peculiar 
structure,  which  is  shown  in  transverse  sections  of  the  tusks  (see 


TETRABELODON.  25 

Table-case  24),  and  appears  as  a  series  of  crossing  lines  curving 
out  from  the  middle  of  the  tooth  and  giving  a  pattern  like  the 
engine-turning  on  the  case  of  a  watch.  This  is  quite  peculiar  to 
elephant-tusks,  and  by  it  even  small  pieces  of  elephant  ivory 
can  be  at  once  distinguished.  This  structure  depends  on  the 
frequent  bending  of  the  tubules  which  make  up  the  dentine,  and 
one  result  of  it  is,  that  true  ivory  is  one  of  the  most  perfectly 
elastic  of  substances,  and  is  therefore  specially  suitable  for  making: 
billiard  balls.  This  form  of  ivory  is  not  found  in  either  the  upper 
or  lower  tusks  of  Moeritherium  and  Palaomastodon  or  in  the 
lower  tusks  of  Dinotherium,  and  appears  for  the  first  time  in 
the  large  upper  tusks  of  Tetrabelodon  angmtidens.  In  some 
of  the  American  Tetrabelodonts  in  which  the  lower  tusks  are 
very  large,  this  structure  seems  to  occur. 

In  the  cheek-teeth  of  Tetrabelodon  angustidens  (fig.  16  A) 
great  changes  have  also  taken  place.  The  milk-molars  are  still 
replaced  by  premolars,  but  these  are  quickly  dropped  out 
(fig.  13  B).  This  is  chiefly  the  result  of  the  great  increase  in 
size  of  the  true  molars,  particularly  of  the  third,  which  is  not 
accompanied  by  a  corresponding  increase  in  the  length  of  the 
tooth-bearing  portion  of  the  jaws,  so  that  there  is  not  room  for 
the  premolars  and  molars  to  remain  in  position  at  the  same 
time.  The  consequence  of  this  is.  that  as  the  posterior  molars 
are  cut  they  move  forward  to  take  up  their  position  in  the  jaw, 
thrusting  out  the  teeth  in  front  of  them  so  that  in  the  adult 
only  the  two  large  back  molars  remain  on  each  side  in  both 
jaws,  and  in  old  individuals  perhaps  only  the  last  is  left.  This 
mode  of  replacement  is  shown  in  fig.  13  B.  In  this  species, 
while  the  first  and  second  molars  still  have  only  three  ridges, 
as  in  Palceomastodon,  the  last  commonly  has  five,  and  all  are 
proportionately  very  large. 

In  the  mandible  (fig.  12)  the  anterior  portion  is  extremely  long 
and  projects  much  further  beyond  the  skull  than  it  does  in  Palao- 
mastodon ;  and,  indeed,  it  is  in  this  species  that  we  have  the 
greatest  degree  of  lengthening  of  the  lower  ja\v.  The  two  lower 
incisors,  as  in  Palaomastodon,  help  to  add  to  the  length,  and 
were  no  doubt  used  for  grubbing  in  the  earth.  The  remarks 


xJ(>  ELEPHANTS. 

made  about  the  upper  cheek-teeth  are  equally  true  of  the 
lower.  The  neck  seems  to  have  been  a  little  longer  and  more 
flexible  than  in  the  modern  elephant,  but  the  limbs  and  other 
parts  were  much  the  same.  This  animal  when  living  (fig.  14) 
must  have  been  still  more  like  an  elephant  than  Palteo- 
mastodon,  and  the  most  noticeable  difference  would  be  that 
here  also,  instead  of  the  flexible  trunk,  there  was  a  long  stiff 

Fig.  14. 


Restoration  of  Tetrabelodon  aiigustidens. 

snout,  which  was  supported  by  the  elongated  front  of  the  lower 
jaw.  Probably  the  end  of  the  upper  lip  and  nose  was  free  and 
movable,  and  may  even  have  been  able  to  grasp  objects  to  some 
extent,  but  the  whole  arrangement  seems  to  have  been  rather 
clumsy.  In  most  groups  of  animals  as  size  increases  the  length 
of  the  neck  becomes  greater  in  proportion,  so  that  the  animal  can 
still  reach  the  ground;  but  in  these  early  elephants,  in  spite  of 


TETRABELODON. 


27 


the  great  increase  in  size,  the  neck  actually  shortened,  audit  was 
only  this  extraordinary  lengthening  of  the  snout  that  enabled 
the  animals  to  reach  the  ground.  It  seems  certain  that  all  the 
sub-divisions  of  the  Proboscidea  must  have  passed  through  this 
iongirostrine  stage. 

The   next  stage  in  this  strange  history  is  found  in  Tetra- 
belodon  longirostris  (fig.  15,  16)  (Pier-cases  41,  42  ;  Table-case 


Skull  and  mandible  of  Tetrabelodon  longirostris,  from  the  Lower 

Pliocene,  Eppelsheim,  Hesse-Darmstadt. 
».,  lower  incisor;  m.  2-3,  second  and  third  molars.     About  J^  nat.  size. 

23),  aji  elephant  of  which  the  remains  are  common  in  the  Lower 
Pliocene  of  Eppelsheim  in  Germany  and  other  localities.     In 


4O  ELEPHANTS. 

this  animal  the  skull,  so  far  as  known,  does  not  differ  to  any 
great  extent  from  that  of  Tetrabelodon  angustidens.  The  teeth, 
however,  have  advanced  considerably  in  size  and  complication. 
The  first  and  second  molars  may  have  four  or  five  trans- 
verse ridges,  while  in  the  last  there  may  be  as  many  as  six 

Fig.  10. 


Second  and  third  lower  molars  of  (A)  Tetrabelodon  angustidens  and 
(-B)  Tetrabelodon  longirostris.     £  nat.  size. 

ridges  (fig.  16  B).  Only  one  of  the  milk- molars  is  now 
replaced  by  a  premolar,  and  both  this  and  the  other  milk- 
molars  are  early  pushed  out  by  the  forward  growth  of  the 
large  molars,  only  two  of  which  at  most  on  each  side  remain 


TET11ABELODON. 


29 


in  position  in   old   animals.       It  is  in   the   lower  jaw,  how- 
ever,   that   the    chief   changes   have   taken   place.      Here  the 

Fig.  17. 


Mandible  of  Tetrabelodon  (Rhynchotheriuni)  dinotherioides,  from  the 
Loup  Fork  Beds,  North-Western  Kansas. 

A.  Eight  side  of  mandible.     iV  nat.  size. 

B.  Upper  view  of  entire  mandible.     TV  nat.  size. 

C.  Upper  view  of  third  right  lower  molar,    g-  nat.  size. 

alv.j  alveolus  of  tusk ;  cond.,  condyle  ;  cor.,  coronoid  process  ; 
m3j  third  lower  molars. 

elongated  anterior  part  (fig.  15),  so  striking  in  the  last  type,  has 
become  shortened  till  it  projects  but  little  in  advance  of  the 


30  ELEPHANTS. 

skull,  and,  although  its  upper  surface  is  still  deeply  grooved  and 
spout-like  as  in  the  earlier  forms,  the  lower  incisors  no  longer 
meet  in  the  middle  line  and  prolong  the  spout,  but  are  rounded, 
directed  downward,  and  separated  from  one  another.  In  this 
animal  it  is  clear  that  the  lower  jaw  was  shortening  np  and  could 
no  longer  reach  the  ground,  but  doubtless  the  fleshy  upper  lip 
and  nose,  now  freed  from  their  bony  support  for  at  least  part 
of  their  length,  became  flexible  and  better  adapted  for  grasping 
the  animal's  food.  In  fact,  this  species  must  have  looked  much 
the  same  as  a  modern  elephant,  except  that  it  had  a  longer  chin 
bearing  a  pair  of  small  downwardly  directed  tusks. 

In  some  of  the  American  Tetrabelodons  of  about  the  same 
age  as  T.  longirostris,  the  lower  tusks,  instead  of  undergoing 
reduction,  seem  to  have  become  greatly  enlarged,  and  at  the 
same  time  the  symphysial  portion  of  the  mandible  is  slightly 
deflected,  so  that  the  mandible  with  its  tusks  is  to  some  degree 
similar  to  that  of  Dinotherium.  An  example  of  this  form  of 
jaw  is  seen  in  the  case  of  the  mandible  of  a  Tetrabelodon 
(T.  dinotherioides)  from  the  Loup  Fork  Beds  (Upper  Miocene) 
of  Kansas,  exhibited  in  Pier-case  42  (fig.  ]  7) . 

DINOTHERIUM. 

Tetrabelodon  dinotherioides  has  no  near  relationship  with 
Dinotherium  (fig,  18)  (Wall-case  43 ;  Case  C),  which  forms  a 
side  branch  of  the  Proboscidea,  and  is  widely  different  from 
all  the  other  members  of  the  group.  The  earliest-known 
member  of  the  genus  is  Dinotherium  cuvieri,  a  comparatively 
small  animal,  which  is  found  in  the  same  deposits  as  the  earliest- 
known  remains  of  Tetrabelodon  angustidens,  and,  as  in  the  case 
of  that  species,  its  ancestors  probably  lived  in  Africa,  though  up 
to  the  present  no  traces  of  them  have  been  discovered.  In  the 
later  Miocene  beds  occur  a  number  of  species,  some  of  enormous 
size  (e.  g.,  D,  gigantissimum  from  Roumania).  The  genus  finally 
disappears  in  Lower  Pliocene  times.  The  chief  peculiarity 
of  these  animals  is  that  the  front  part  of  their  lower  jaw  is 
turned  sharply  downward  and  bears  two  large  tusks  (fig.  18, 
Case  C) ;  probably  there  were  no  tusks  in  the  upper  jaw.  The 
skull  js  remarkable  for  the  great  expansion  of  the  occipital 


DIXOTIIERIUM. 


31 


surface,  which  is  strongly  inclined  forward  :  there  seems  to 
have  been  scarcely  any  development  of  spongy  bone  in  the 
occipital  region.  The  teeth  are  of  a  much  simpler  character 
than  those  found  in  the  Mastodon-elephant  line.  In  the  upper 
jaw  of  the  adult  there  are  two  premolars,  both  simpler  than 
the  molars;  of  these  molars  the  anterior  one  consists  of  three 
transverse  crests,  the  other  two  of  two  crests  only,  a  notable 
peculiarity,  since  in  the  other  Proboscidea  it  is  the  hindermost 

Fig.  18. 


Skull  of  Dinothcrium  giganteum  from  the  Lower  Pliocene  of  Eppelsheiin, 
Hesse-Darmstadt.     jV  nat.  size. 

molar  which  is  the  most  complex.  The  posterior  milk-molar 
also  has  three  crests.  In  the  lower  jaw  in  addition  to  the 
down-turned  tusks  there  are  two  premolars  and  three  molars. 
As  in  the  upper  jaw,  the  premolars  are  simpler  than  the  molars  : 
the  anterior  molar  has  three  crests,  the  second  and  third  two 
only,  though  in  the  last  there  may  be  a  trace  of  a  third.  In 
the  young  there  are  three  milk-teeth,  the  hinder  one  having 


32  ELEPHANTS. 

three  crests,  like  the  anterior  true  molar.  All  the  molars  and 
premolars  remain  in  use  throughout  the  animal's  life,  a  condition 
already  lost  in  the  earliest  Tetrabelodons.  It  has  been  suggested 
that  Dmotherium  was  an  aquatic  animal,  but  there  is  nothing 

Fig.  19. 


Mandible  of  a  young  individual  of  Mastodon  americanus,  showing  the  small 
remnants  of  the  lower  incisors.  In  the  adult  these  are  lost.  From  a 
Pleistocene  deposit,  North  America.  About  %  nat.  size. 

in  the  structure  of  the  limbs  to  give  any  support  to  this  idea> 
though  the  lowness  of  the  crowns  of  the  teeth  probably 
indicates  that  it  lived  on  soft  herbaceous  vegetation,  such  as 
may  have  grown  in  swampy  places. 


MASTODON.  33 

MASTODON. 

In  Tetrabelodon  longirostris  the  main  characteristics  of  the 
modern  elephants  are  already  established,  and  the  later  changes 
of  importance  include,  (1)  the  still  further  reduction  of  the 
inandibular  symphysis  and  the  loss  of  the  lower  incisors,  and 
(2)  the  great  increase  in  the  size  and  complication  of  the 
cheek-teeth.  It  will  be  convenient  to  consider  these  changes 
separately. 

In  the  shortening  of  the  chin  the  next  stage  is  found  in 
Pliocene  forms  like  Mastodon  atticus  ( Pier-case  37)  from  the 
Lower  Pliocene  of  Pikermi.  In  this  the  symphysis,  though 
much  shortened,  is  still  more  or  less  spout-like,  and  in  very 
young  individuals  the  incisors  may  be  present,  though  they  are 
soon  shed  ;  .the  absence  of  these  teeth  in  the  adult  is  the  chief 
character  distinguishing  the  genus  Mastodon  (fig.  19)  from 
Tetrabelodon.  One  of  the  best-known  species  belonging  to  this 
stage  of  development  is  Mastodon  arvernensis  (Pier-cases  37—40), 
which  is  found  in  Europe  in  Pliocene  deposits;  in  it  the  lower 
incisors  seem  to  be  entirely  wanting  and  the  anterior  molars 
have  four  transverse  ridges.  A  nearly  allied  species,  M .  sivalensis 
(fig.  21),  from  the  Pliocene  of  India,  is  notable  as  showing  a 
tendency  to  acquire  five  ridges  to  its  molars. 

The  region  in  which  the  passage  from  the  Mastodons  to  the 
true  elephants  occurred  seems  to  have  been  Southern  Asia, 
where,  in  a  succession  of  Pliocene  and  Pleistocene  deposits, 
there  is  a  complete  series  of  forms  passing  from  the  Mastodon 
up  to  the  recent  Indian  Elephant  (Pier-cases  34-37).  How 
far  these  changes  may  have  gone  on  in  the  rest  of  the  Northern 
Hemisphere  is  not  known,  but  the  history  of  the  Mastodons 
in  America  is  rather  different  from  that  of  the  Old  World 
forms.  The  Proboscidea  make  their  first  appearance  in  North 
America  in  the  Miocene,  and  are  there  represented  by  a  great 
variety  of  forms.  Some  (see  pages  29—30)  have  the  lower  tusks 
much  enlarged  and  borne  in  a  down-turned  symphysis  ;  these 
are  regarded  by  Professor  Osborn  as  belonging  to  a  distinct 
genus  Uhynchotherium  ;  one  of  them  is  shown  in  figure  17. 
Others  are  straigl it-jawed  Tetiabelodonts,  some  with  compara- 
tively short  symphyses  (e.  g.,  T.  productus\  some  with  the 


34  ELEPHANTS. 

symphysis  greatly  elongated  (e.  g.,  T.  giganteus).  These  with  the 
later  Mastodons  probably  represent  several  waves  of  immigration 
from  Asia.  Somewhere  about  the  beginning  of  the  Pliocene 
some  of  these  North  American  forms,  probably  short-jawed 
Tetrabelodonts,  migrated  into  South  America,  where  several 
peculiar  species  are  found  which  persisted  with  little  change  till 
the  Pleistocene.  Probably  the  reason  why  these  Mastodons, 
as  well  as  M.  americanus  (Stand  B)  of  North  America,  con- 
tinued in  a  comparatively  primitive  condition  is  to  be  found 
in  their  isolation  and  freedom  from  competition.  One  Soutli 
American  species,  M.  andium  (Pier-cases  39,  40),  is  par- 
ticularly interesting  on  account  of  its  variability,  especially  in 
the  length,  of  the  chin  and  in  the  presence  or  absence  of  the 
lower  tusks.  Some  of  these  differences  are  due  to  sex  and,. 

Fig.  20. 


Vertical  longitudinal  section  of  a  molar  tooth  of  a  Mastodon,  showing  the 
low  crown,  the  open  valleys  between  the  cross-ridg'es,  and  the  thick 
enamel  (I),  c.,  dentine.  |  nat.  size. 

perhaps  age,  but  the  variations  are  no  doubt  mainly  due 
to  the  fact  that  the  symphysis  and  lower  tusks  were  undergoing 
reduction  and  that  the  latter  were  about  to  disappear  altogether. 
Neither  in  North  nor  in  South  America  does  it  appear  that  the 
Mastodons  gave  rise  to  more  advanced  types,  arid  the  presence  in 
the  Pleistocene  of  North  America  of  true  elephants  (E.  columbi 
and  E.  primigenius)  is  due  to  immigration  from  Asia.  No- 
species  of  Elephas  reached  South  America. 

To  return  to  the  scries  of  stages  of  development  found  in 
Southern  Asia,  the  first  species  that  need  be  considered  is 
Mastodon  cautleyi  (Table-case  23),  which  in  the  character  of  its 


ELEPHAS.  35 

teeth  is  nearly  related  to  Tetrabelodon  Ion  giro  stris,  but  the  ridges 
of  the  molars  are  comparatively  higher.  There  is,  however,  as 
yet  no  cement  in  the  valleys  (fig.  20),  which  are  more  or  less 
obstructed  by  small  tubercles,  and  some  of  the  cusps  wear  into  a 
trefoil  pattern,  as  in  Tetrabelodon  angustidens  and  T.  longirostris. 
While,  however,  the  anterior  molars  are  almost  identical  with 
those  of  T.  longirostris ,  the  posterior  lower  molar  is  very  similar 

Fig.  21. 


Grinding-surface  of  a  lower  molar  tooth  of  Mastodon  sivalensis. 
From  the  Lower  Pliocene  of  the  Siwalik  Hills,  India,     f-  nat.  size. 

to  that  of  M.  laiidens,  which  in  its  turn  approaches  Elephas 
(Stegodon)  clifti  (fig.  22)  very  closely.  In  M.  latidens  there  are, 
as  a  rule,  five  transverse  ridges  in  the  second  upper  molar  and 
six  in  the  last. 

ELEPHAS. 

The  next  stage  is  represented  by  Elephas  (Stegodon)  clifti 
(fig.  22)  (Pier-cases  35,  36  ;  Table-case  24,  Stand  K).  With 
this  species  we  reach  the  true  elephants,  though  the  molars 
have  much  lower  crowns  and  fewer  transverse  ridges  than  in 
the  modern  species  of » Elephas  ;  and,  in  fact,  these  earlier 
forms  are  sometimes  separated  into  another  genus  called 
Stegodon.  Since,  however,  no  real  line  can  be  drawn  between 
them  and  the  later  types  it  is  perhaps  best  to  call  all  Elephas ,  but 
distinguish  these  earlier  forms  by  adding  the  name  Stegodon  in 
brackets  as  above.  In  all  this  group  the  lower  incisors  have 
entirely  disappeared,  the  anterior  elongation  of  the  chin  at 
the  same  time  being  reduced  to  a  mere  peg-like  process 
(figs.  24  &  31),  and  a  greater  or  less  amount  of  cement  (see 

D2 


36  ELEPHANTS. 

above,  p.  8)  fills  the  transverse  valleys  in  the  crowns  of  the 
molars  (fig.  23).  In  Elephas  (Steyodori)  clifti  the  number  of 
ridges  is  greater  than  in  Mastodon  latidens.  In  order  to  express 
briefly  the  number  of  ridges  in  the  molars  of  this  and  other  species, 
a  formula  is  used,  thus  :  —in  E.  (Steyodon)  clifti  the  formula 
M  1  ~,  M  2  °,  M  3  J=|,  means  that  in  the  first  true  molar  (M  1) 
there  are  in  the  upper  jaw  6-7  ridges,  while  in  this  case  the 
number  in  the  lower  is  not  known.  In  the  second  molar  (M  2) 
there  are  6  in  the  upper,  the  lower  being  uncertain,  while  in 
the  last  molar  (M  3)  there  are  7-8  ridges  in  both  the  upper  and 
lower  jaw.  It  will  be  seen,  therefore,  that  the  numerator  of  the 

Fig-.  22. 


G  rinding-surface  of  an  upper  molar  tuoth  of  Elephas  (Stegodon)  clifti.     From 
Lower  Pliocene,  Siwalik  Hills,  India.     Showing  six  transverse  ridges. 


fractions  represents  the  number  of  ridges  in  the  upper  teeth, 
the  denominator  the  number  in  the  lower.  When  the  two 
numbers  are  given  thus,  6-8,  it  means  that  the  number  of 
ridges  varies  between  them.  This  formula  will  be  employed 
below  in  describing  the  molars,  and  a  table  showing  the  gradual 
increase  in  the  number  of  ridges  will  be  given  at  the  end. 

In  E.  clifti  premolars  are  still  developed,  but  must  have 
been  pushed  out  almost  as  soon  as  the  milk-molars  they  replace. 
The  crowns  of  the  molars  are  quite  low,  and  there  is  only  a 
small  quantity  of  cement  in  the  valleys  between  the  ridges. 

In  Elephas  (Steyodori)  bombifrons  andE.  (£.)  insiynis  (fig.  23), 


ELEPHAS  (STEGODON). 


37 


which  represent  the  next  stage,  the  transverse  ridges  are  some- 
what more  numerous  and  at  the  same  time  are  higher,  and  the 
valleys  are  filled  with  cement  to  a  greater  degree.  Nevertheless, 


Vertical  longitudinal  section  of  molar  tooth  of  Elephas  (Steyodori)  insignis. 
From  Lower  Pliocene,  Siwalik  Hills,  India.  Showing  the  wide  valleys 
between  the  cross-ridges  filled  with  cement  (a),  the  dark  band  marked 
b  being  the  enamel  and  beneath  that  the  dentine  (c).  £  nat.  size. 

these  differences  are  not  very  marked,  and  in  the  case  of  indi- 
vidual teeth  it  is  often  difficult  to  be  sure  to  which  of  these 

Fig.  24. 


Skull. and  mandible  of  Elephas  yanesa,  showing  the  immense  upper  tusks 
and  the  shortened  chin.  From  Lower  Pliocene,  Siwalik  Hills,  India. 
About  -g-V  nat.  size. 

species  they  belong,  In  some  of  the  Stegodont  elephants  the 
tusks  attain  an  enormous  size  :  for  instance,  in  a  skull  of 
Etephas  (Stegodon]  ganesa  (fig.  24),  exhibited  in  the  gallery 


38 


ELEPHANTS. 


(Stand  K),the  tusks  project  for  a  distance  o£  9  ft.  9  in.  beyond 
the  sockets. 

*  In  the  next  stage  we  pass  from  the  low-crowned  Stegodont 
group  to  animals  in  which  the  ridges  are  considerably  higher 

Fig-.  L>5. 


Grinding-surface  of  an  incomplete  upper  molar  of  Elephas  planifrons. 
From  Lower  Pliocene,  Siwalik  Hills,  India.     §  nat.  size. 

and  the  valleys  completely  filled  with  cement ;  this  is  called 
the  Loxodont  group.  The  most  primitive  member  is  Elephas 
planifrons  (figs.  25  &  26)  (Pier-case  34  ;  Table-case  24),  in  which 

Fig.  26. 


Vertical  longitudinal  section  of  molar  tooth  of  Elephas  planifrons,  showing 
the  deeper  and  narrower  valleys  completely  filled  with  cement  («).  The 
enamel-layer  is  marked  b,  the  dentine  c.  •§•  nat,  size. 

the  posterior  molars  may  have  as  many  as  twelve  ridges.     This 
is  the  last   of   the  elephants    in  which    premolars   have   been 


ELEPHAS.  O1J 

observed  ;  these  teeth  are  small  and  closely  crowded  up  beneath 
the  milk-molars,  so  that  when  those  teeth  are  greatly  worn  the 
premolars  are  exposed  to  view,  and  are  no  doubt  shed  as  soon 
as,  or  even  before,  the  posterior  part  of  the  niilk-molars  they 
should  replace. 

The  species  E.  meridionalis  (fig.  27)  (Pier-case  33;  Table- 
case  20),  of  which  remains  are  found  in  the  Pliocene  of  Middle 
and  South  Europe,  seems  to  be  closely  related  to  E.  planifrons, 
and  is  in  about  the  same  stage  of  evolution,  or  perhaps  a  little 
more  advanced.  The  last  molars  may  have  13-14  ridges, 
and  in  some  cases  approach  the  condition  seen  in  E.  hysudricus. 
E.  meridionalis  attained  enormous  dimensions,  some  individuals 

Fig.  27. 


Grinding-surface  of  upper  molar  of  Elephas  meridionalis. 
Forest  Bed,  Norfolk.     About  £  nat.  size. 

probably  standing  about  15  feet  in  height  at  the  shoulder. 
Remains  of  this  species  occur  in  the  Forest  Bed  of  Norfolk 
(see  Table-case  20)  and  in  the  Upper  Pliocene  deposits  of  the 
Val  d'Arno  and  the  Auvergne.  According  to  Leith  Adams 
('  British  Fossil  Elephants/  p.  232) ,  the  molars  are  distinguished 
by  the  following  characters: — " Crowns  very  broad ;  columns 
short  as  compared  with  E.  antiquus,  and  generally  as  com- 
pared with  E.  primigenius ;  the  enamel  of  the  discs  thick  and 
rarely  crimped,  but  usually  uneven,  looped  or  channelled ; 
plates  wide  apart,  with  thick  wedges  of  cement."  Numerous 
teeth  of  this  species  are  shown  in  Table-case  20. 

In  this  species  when  the  plates  come  into  wear  the  lateral 


40 


ELEPHANTS. 


columns  tend  to  fuse  into  laminae  while  the  central  column 
remains  for  a  time  distinct  and  more  or  less  circular  in  section 
(see  fig.  27)  ;  in  E.  antiquus  the  lateral  columns  tend  to  remain 
annular,  while  the  medials  unite  into  a  lamella  (fig.  28). 

Returning  to  the  Indian  series,  the  next  stage  may  be  taken 
as  represented  by  Elephas  hysudricus  (Pier-case  33) ,  in  which 
there  is  a  considerable  increase  in  the  height  of  the  teeth  and 
in  the  number  of  the  ridges.  The  skull  is  in  many  respects 
similar  to  that  of  E.  maximus  (E.  indicus),  the  modern  Indian 
elephant,  which  may  have  been  its  direct  descendant.  E.  hysu- 
dricus, like  E.  meridionalis,  sometimes  attained  a  very  large 
size.  This  species  occurs  at  the  end  of  the  Pliocene  and 

Fisr.  28. 


Grinding-surface  of  second  lower  molar  of  Elephas  antiquus  from  the 
Pleistocene  of  Grays,  Essex.     £  nat.  size. 


perhaps  in  the  early  Pleistocene  beds  of  the  Narbada.  Con- 
temporary with  it  was  E.  antiquus  (fig.  28)  (Pier-case  33  ; 
Table-cases  19, 19  A),  an  elephant  found  in  the  late  Pliocene  and 
early  Pleistocene  of  Europe.  This  species,  in  which  the  molar 
teeth  are  relatively  small  and  tusks  nearly  straight,  sometimes- 
attained  a  gigantic  size.  A  skeleton  recently  found  at  Upnor, 
near  Rochester  (Pier-case  31),  indicates  an  animal  standing 
about  fifteen  feet  high  at  the  shoulder,  the  humerus  being 
4  ft.  4  in.  long  (1/322  meters),  a  foot  longer  than  the  humerus.' 
of  an  African  Elephant  said  to  have  been  lift.  4  in.  high  at 
the  shoulder.  A  variety  of  this  species,  E.  antiquus  recki  from 
East  Africa,  likewise  attained  a  gigantic  size.  E.  zulu  from 
Zululand  is  probably  a  related  form.  In  India  E.  antiquus  is 


ELEPHAS.  41 

represented  by  E.  namadicus  ;  in  this  species  the  skull  is  peculiar 
from  the  development  of  a  sort  of  overfolded  ridge  on  its- 
frontal  portion,,  forming  an  overhanging  fold  on  the  fore- 
head (see  Pier-case  34).  In  the  changes  that  took  place 
in  the  distribution  of  land  and  water  at  the  end  of  the 
Pliocene  and  the  beginning  of  the  Pleistocene,  portions  of  the 
regions  inhabited  by  Elephas  antiquus  and  its  varieties  became 
isolated  as  islands,  and  in  these  restricted  habitats  the  species 
became  dwarfed,  and  the  dwarf  forms  in  the  different  islands 
at  the  same  time  became  specifically  distinct  from  one  another. 
Instances  of  these  small  forms  are  Elephas  melitensis,  E.  mnai- 
driensis,  E.  Cypriotes,  and  E.  creticus  (Table-cases  17  A, 
21,  21  A).  E.  melitensis  and  E.  mnaidriensis  are  found 
in  Malta.  Of  the  first-named  species  a  small  form,  sometimes 
called  E.  falconeri,  did  not  stand  more  than  about  three 
feet  high  at  the  shoulder.  The  ridge-formula  of  the  molar 
teeth  is  :— M  1  g,  M  2  £,  M  3  jgf.  A  large  collection  of 
remains  of  these  species,  obtained  by  Admiral  Spratt  and 
Professor  Leith  Adams,  is  shown  in  Table-cases  21  &  21  A. 
E.  mnaidriensis  is  also  found  in  Sicily  ;  probably  this  species, 
which  is  larger  than  E.  melitensis ,  represents  the  intermediate 
stage  between  it  and  E.  antiquus.  E.  Cypriotes  from  Cyprus 
and  E.  creticus  from  Crete  were  both  discovered  and  described 
by  Miss  D.  M.  A.  Bate,  who  collected  the  specimens  shown 
in  Table-case  17  A. 

Turning  again  to  the  main  line,  we  find  that  Elephas  hysu- 
dricus  probably  passed  into  some  such  species  as  E.  armeniacus 
(Table-case  17),  which  in  many  respects  is  intermediate  between 
the  Mammoth  (E.  primiyenius)  (Pier-cases  30-32  ;  Table-cases 
17-19)  and  the  living  Indian  Elephant  (E.  maximus).  The 
Mammoth  seems  to  represent  the  highest  pitch  of  evolution 
attained  in  the  Elephantidse,  being  in  some  respects  in  advance 
even  of  the  Indian  Elephant.  It  is  here  that  we  meet 
with  the  greatest  number  of  ridges  in  the  molars  (fig.  29),  the 
formula  being  M  1  ££,  M  3  JJlJt  M  3  £^.  These  teeth 
represent  the  culmination  of  the  long  series  of  changes  above 
described,  all  tending  to  increase  the  efficiency  of  the  molars 


42 


ELEPHANTS. 


as  grinding  organs.  The  great  size,  and  especially  height,  of 
the  crown  gives  them  a  prolonged  period  of  wear,  while  the 
numerous  alternating  plates  of  enamel,  dentine,  and  cement, 
of  different  degrees  of  hardness,  ensure  that  the  grinding- 
surface  will  remain  sufficiently  rough  for  its  purpose  through- 
out the  period  during  which  the  tooth  remains  in  use.  The 
Mammoth  was  a  very  widely-distributed  form,  being  found  all 
over  Northern  Europe,  Asia,  and  America,  and  it  seems  to 
have  been  particularly  abundant  in  Siberia  and  the  islands  to  the 
north,  where  remains  occur  in  great  abundance,  and  whence 
the  tusks  are  actually  exported  for  commercial  purposes.  The 

Fig.  29. 


Grinding-surface  of  molar  tooth  of  the  Mammoth  (Elephas  primigeniui), 
showing  some  still  unworn  posterior  plates.     About  £  nat.  size. 

extinction  of  the  Mammoth  appears  to  have  been  a  compa- 
ratively recent  event,  and  in  Siberia  portions  of  carcases  with 
the  skin  and  flesh  in  good  preservation  are  found  in  the  frozen 
tundras.  An  instance  of  this  kind  is  illustrated  by  drawings 
and  photographs  on  the  pillar  between  Pier-cases  31—32.  In 
this  instance  the  animal  seems  to  have  fallen  into  a  hole  and  to 
have  died  in  its  efforts  to  scramble  out.  The  mouth  was  found 
:still  filled  with  the  grass  on  which  the  animal  was  browsing  at 
the  time  when  it  met  with  the  accident.  This  individual, 
restored  and  mounted  in  the  attitude  in  which  it  was  found, 
is  now  exhibited  in  the  Academy  of  Sciences  at  Petrograd, 
and  shows  with  many  others  that  the  Mammoth  was  covered 
with  a  reddish-brown  wool  and  long  dark  hair,  while  the  tail 
ended  in  a  large  tuft  of  hair.  A  piece  of  the  skin  with  its 


ELEPHAS. 


woolly  covering  and  some  of  the  long  hair  are  shown  in  Pier- 
case  31.  Further  confirmation  of  this  peculiarity  of  the 
Mammoth  is  found  in  the  rude  sketches  scratched  on  ivory 
by  early  Man,  who  was  evidently  quite  familiar  with  the 
animal.  A  reproduction  of  one  of  these  early  drawings  is 
shown  near  Wall-case  1. 

The  finest  Mammoth    skull   hitherto    collected  in  England 
is  shown  in.  Case  M  :    this  specimen  was  obtained  from  the 

Fig.  30. 


Grinding-surface  of  upper  molars  of  (A)  the  Asiatic  and  (B)  the 
African  Elephant.     About  -|  nat.  size. 

Pleistocene  brick-earth  at  Ilford  in  Essex.  Most  of  the  skeleton 
seems  to  have  been  found  with  it,  but  the  bones  were 
unfortunately  destroyed  before  their  interest  was  recognised. 
The  tusks  in  this  skull  are  10  feet  6  inches  in  length  beyond 
the  sockets. 

In  North  America  several  species  of  Mammoth  occur,  such 
as  JZ.  imperator  and  E.  jeffersoni ;    some  of  these  attained  a 


44  ELEPHANTS. 

much  larger  size  than  E.  primigenius,  and  possessed  teeth  of  a 
more  primitive  character,  approximating  to  those  of  the 
probably  ancestral  E.  meridionalis  and  E.  hysudricus. 

The  Indian  elephant,  E.  maximus  (fig.  30  A)  (Stands  G,  J)r 
one  of  the  two  surviving  species  of  the  suborder,  is  found  in  India, 
Ceylon,  and  the  Malay  Peninsula  to'Sumatra.  The  chief  pecu- 
liarities of  the  species,  distinguishing  it  from  the  African  elephant, 
are  the  flatness  of  the  forehead,  the  comparatively  small  ears, 
the  presence  of  a  single  finger-like  process  at  the  front  of  the 
end  of  the  trunk  (fig.  31  A).  As  might  be  expected  from  the 
wide  range  of  this  species,  different  local  forms  can  be  dis- 
tinguished, and  in  some  cases  these  have  even  been  regarded  as- 
specifically  distinct,  as,  for  instance,  the  elephant  of  Sumatra, 

Fig.  31. 


Skull  of  the  African  Elephant  (Elephas  africanus).     About  j-8  nat.  size. 

which  has  been  called  E.  sumafranus.  It  seems,  however,  that 
all  are  merely  geographical  races  of  the  same  animal.  The 
Ceylon  form  is  said  to  be,  as  a  rule,  tuskless,  and,  although  tusk- 
bearing  forms  do  occur  in  the  island,  they  may  be  either  animals 
imported  from  the  mainland  of  India  or  the  result  of  former 
interbreeding  with  such.  In  India,  also,  some  individuals,  called 
Muchnas,  are  tuskless  or  have  very  small  tusks  (see  mounted 
skin,  Stand  G).  The  Sumatran  type  differs  in  being  rather 
more  slightly  built,  and  in  possessing  a  rather  longer  trunk  and 
more  expanded  end  to  its  tail.  The  elephants  from  Further 
India  and  the  Malay  Peninsula  are  probably  also  a  distinct 


ELEPHAS.  45 

race  which  seems  especially  liable  to  produce  albino  forms, 
the  white  elephants  of  Siam  and  Burma  being  well  known. 

The  origin  of  the  other  living  species  of  elephant,  Elephas 
ajricanus  (fig.  31),  is  not  very  clearly  known,  owing  to  the  want 
of  fossil  remains.  Several  closely-allied  species, e.g.  E.  atlariticus, 
have  been  described  from  the  Pleistocene  of  Algeria,  but  110 
form  that  can  be  regarded  as  ancestral  has  been  found  in  the 
Tertiary  Beds  of  Africa.  It  is  now  generally  supposed  that 
E.  africanus  arose  from  some  at  present  unknown  Stegodont, 
and  not  as  prevously  suggested  from  an  E.  antiquus-like  animal 
in  which  the  molar  teeth  were  already  more  complex. 

The  African  Elephant  (Central  Hall)  to-day  ranges  very  widely 
over  Africa  south  of  the  Sahara,  but  fossil  remains  have  been 
found  in  Northern  Africa  and  in  the  south  of  Europe.  It  is 
distinguished  by  its  convex  forehead  (Stands  H,  I),  its  very 

Fig.  32. 


A 

Tip  of  trunk  of  (A)  the  Asiatic  and  (B)  the  African  Elephant. 

large  ears,  and  by  the  presence  of  two  finger-like  processes  on 
the  tip  of  the  trunk  (see  fig.  32  B) .  The  molar  teeth  are  con- 
siderably simpler  than  those  of  the  Indian  species  (see  fig.  30  B), 
the  ridges  being  fewer  in  number  and  widening  out  in  the 
middle  in  a  peculiar  manner;  the  teeth  also  are  relatively 
smaller  than  in  other  elephants. 

It  has  lately  been  shown  that,  although  there  is  only  a  single 
species  of  African  Elephant,  nevertheless,  in  different  parts  of 
the  continent,  there  are  different  local  races  which  may  perhaps 
be  regarded  as  subspecies,  and  are  in  fact  species  in  the  making. 
Differences  in  the  form  of  the  skull  of  these  different  races  can 
be  detected,  but  the  most  striking  characters  distinguishing 
them  from  one  another  are  the  size  and  shape  of  the  ears. 


46  ELEPHANTS. 

According   to  Mr.  Lydekker  the  distinctive  features  of  these 
local  races  are  : — 

I.  In  the  Addo   Bush,   or  East    Cape,    Elephant    (Elephas 
ofricanus  capensis)  the  ears  are  rather  small,  somewhat  square 
in  shape,  with  rounded  corners,  and  a  small,  sharply  pointed, 
angular  lappet  at  the  lower  angle.      The  forehead  falls  away 
towards  the  temples,  so  as  to  appear  highly  arched.     Several 
young  individuals  of  this  variety  are  now  shown  in  the  Central 
Hall. 

II.  The  West  Cape  Elephant  (E.  a.  toxotis)  has  the  ears  much 
larger  (4  ft.  5  in.  in  a  female  8  ft.  8  in.  high),  longer,  and 
semi-oval  in  shape  ;  although,  as  in  the  preceding  race,  sharply 
inflected  at  the  lappet.     (Later  regarded  by  Lydekker   as   a 
synonym  of  I.) 

III.  In  the  Matabeleland  race  (E.  a.  selousi)  the  ear  is  much 
less  elliptical  than  in  the  West  Cape  Elephant,  and  approaches 
more  to  that  of  the  Camerim  race,  but  agrees  with  that  of  the 
former  in  that  the  lappet  underhangs  the  jaw  and  chin. 

IV.  In  the  West  African  Elephant  (E.  a.  cyclotis),  typically 
from  South  Cameruns,  the  ears  are  very  large,  but  of  quite 
different  shape,  the  contour  being  oval  and  the  lappet  in  the 
form  of  half-ellipse.     The  skin  has  a  mosaic-like  appearance, 
and  its  colour  is  paler  grey  than  in  most  other  races.      The 
Congo  Elephant,  which  comes  very  close  to  this  type,  has  long 
and  slender  tusks. 

V.  The  Masai  Elephant  (E.  a.  knochenhaueri] ,  typically  from 
German  East  Africa,  has  small  triangular  ears,  with  the  lappet 
angulated  and  pointed.     The  exhibited  specimen  (which  stands 
11  ft.  4  in.  in  height,  with  ears  measuring  4  ft.  2J  in.  by  3ft. 
5  in.)  may  belong  to  this  race. 

VI.  In  the  Aberdare  Elephant  (E.  a.  peeli),  typically  from 
the  Aberdare  Mountains,  British  East  Africa,  the  ears  are  pear- 
shaped,  with  the  lappet  very  long,  although  somewhat  rounded 
at  the  tip. 

VII.  The  Lake  Rudolf  Elephant  (E.  a.  cavendishi)  is  nearly 
allied  to  the  last,  but  has  broader  ears,  in  which  the  lappet  is 
shorter. 

VIII.  In  the  Abyssinian,  or  Sudan,  Elephant  (E.  a.  oxyotis) 
the  ears  form  an  elongated  triangle,  with   the   upper  border 


RELATIONSHIPS  OF  THE  TltOBOSCIDEA.  47 

rounded  and  the  lappet  very  sharply  pointed  and  angular.     This 
elephant  attains  very  large  dimensions. 

IX.  The  N.  Somali  Elephant   (E.  a.  orleansi),  on  the  other 
hand,  is  small,,  with  the  upper  border  of  the  small  ears  straight 
and  the  lappet  short  and  distinctly  defined. 

X.  In  the  West  Sudan  Elephant  (E.  a.  rothschildi)  the  ears  are 
in  some  respects  intermediate  between  those  of  the  Abyssinian 
and  those  of  the  West  African  race,  although  approximating  to 
the  former  in  the  shape  of  the  lappet. 

XI.  The  Albert  Nyanza Elephant  has  been  separated  as  E.  #.. 
albertensis  and  is  characterised  by  the  unusually  short  and  broad 
skull. 

A  dwarf  elephant  (Elephas  pumilio)  is  known  from  the  Congo- 
region,  and  another  species  (E/ep/ias  fransseni),  the  so-called 
Water  Elephant,  from  the  neighbourhood  of  Lake  Leopold  IK, 
Congo,  may  also  have  been  a  small  form.  Specimens  of  the 
tusks  of  this  last  species  are  shown  in  the  Central  Hall  and  the 
mounted  skin  is  in  the  East  Corridor. 


RELATIONSHIPS  OP  THE  PROBOSCIDEA. 

The  discovery  of  the  Eocene  Proboscidea  proves  that,  although 
the  elephants  are  no  doubt  rightly  included  among  the  Ungu- 
lata  or  hoofed-animals,  they  are  at  the  same  time  very  widely 
separated  from  the  other  members  of  that  group,  or  at  least 
from  the  existing  members  of  it,  and  seem  to  have  formed  an 
independent  series  from  the  earliest  Tertiary  times,  when  they 
probably  arose  from  some  quite  generalised  form  of  the  primitive 
group  called  the  Condylarthra.  A  very  early  side-branch  from 
the  Proboscidean  stem  is  probably  represented  by  the  Sirenia 
or  Sea-cows,  aquatic  animals  which,  though  now  as  unlike 
elephants  as  possible,  still  possess  a  number  of  anatomical 
peculiarities  in  common  with  them,  so  that  this  relationship 
was  recognised  long  ago.  Recently  a  number  of  Sirenians  have 
been  found  in  the  Eocene  strata  of  Egypt  (Pier-case  30),  one 
in  the  same  horizon  as  Moeritherium.  These  early  Sirenians 
are  much  less  specialised  than  the  existing  forms,  having 
the  full  series  of  teeth  and  a  complete  pelvis,  and  probably  a 


48 


ELEPHANTS. 


functional  hind  limb.  In  many  points  they  resemble  Moeri- 
therium, as,  for  instance,  in  the  form  of  the  brain,  teeth,  and 
pelvis ;  and  it  seems  likely  that  both  they  and  Moeritherium 
had  a  common  ancestor  in  Lower  Eocene  times.  It  was  pro- 
bably a  swamp-living  creature,  some  of  whose  descendants 
became  gradually  more  and  more  exclusively  aquatic  in  their 
habits,  thus  giving  rise  to  the  Sirenia,  while  others  became 
exclusively  terrestrial  and  gave  rise  to  the  elephants  as  described 
above. 

TABLE  SHOWING  THE  RIDGE-FORMULA  OF  THE  TRUE  MOLARS  IN  THE 
APPROXIMATE  LlNE  OF  DESCENT  OF  THE  ELEPHANTS  FROM 
Moeritherium. 


Ml. 

M2. 

M3. 

Moeritherium       

2 
2 

2 
2 

2 
3 

Pal&omastodon    

3 
3 

3 

3 

3 

3 

Tetrabelodon  angustidens    .     .     . 

3 

3 

8 
3 

4—5 
4=5 

„            longirostris   . 

4 
4 

4 
4 

ft—  6 
5=0 

Mastodon  cautleyi    

4 
4 

4 
4 

5 

5 

„          latidens     

4 
4 

4—5 
4—5 

5—6 
5—6 

Elephas  (Stegodon)  ciifti    .     .     . 

6-7 
P 

6 

7—8 
7—8 

,,                „          bombifrons    . 

6 
7 

6—7 
7—8 

8—9 
8—9 

insignis    .      - 

7—8 
7—10 

7—8 
8—12 

9—11 
9—13 

Elephas  planifrons    

7 
7 

8—9 
8—9 

10-12 
10—13 

„       hysudricus  

9—12' 
9—12 

10—12 
12—13 

13—17 
14—18 

12 

16 

24 

,,       maximus      

12 

16 

24—27 

„      primigenius      .... 

9—15 
9—15 

14—16 
14—16 

18-27 
18=27 

A  series  of  specimens  illustrating  the  gradual  increase  in  the 
number  of  ridges  on  the  molars  is  shown  in  Table-case  24. 


Printed  by  TAYLOR  and  FRANCIS,  Red  Lion  Court,  Fleet  Street. 


BRITISH     MUSEUM 

(ffATUJLAL  HISTORY), 

Cromwell  Road,  London,  S.W.  7. 


DATS  AND  HOURS  OF  ADMISSION. 


The  Museum  is  open  to  the  Public,  free  daily — on  WEEK- 
DAYS, throughout  the  year  from  10A.M.,  in 

January  and  February   ...         ...         to  5  P.M. 

March  to  September  (inclusive)  „  6     ,, 

October,  November,  and  December       .,  5    „ 

on  SUNDAYS,  throughout  the  year  from  2.30  to  6  P.M. 

On  Sundays  the  back  galleries  in  the  east  wing  are  closed, 
namely : — Fossil  Fishes,  Fossil  Cephalopods,  Fossil  Shells, 
Starfishes  &c.?  Fossil  Corals,  Fossil  Plants,  and  Special  Fossil 
Collections. 

The  Museum  is  closed  on  Good  Friday  and  Christmas  Day. 

BY  ORDER  OF  THE  TRUSTEES, 

i 

S.  F.  HARMEB, 

I 

Director. 

\ 


14  DAY  USE 

RETURN  TO  DESK  FROM  WHICH  BORROWED 

EARTH  SCIENCES  LIBRARY 

This  book  is  due  on  the  last  date  stamped  below,  or 

on  the  date  to  which  renewed. 
Renewed  books  are  subject  to  immediate  recall. 


13   19ffr 


DEC  29  1978 


LD  21-n50m-6,'60 
(B1321slO)476 


General  Library    . 
University  of  California 
Berkeley