﻿THE 
  AMERICAN 
  LOBSTER. 
  

  

  DESCRIPTION. 
  

  

  The 
  lobster 
  {Homarus 
  amcrkunHs) 
  belongs 
  to 
  that 
  group 
  of 
  the 
  Crus- 
  

   tacea 
  called 
  the 
  Decapoda, 
  because 
  all 
  of 
  its 
  members 
  are 
  provided 
  with 
  

   ten 
  feet, 
  more 
  or 
  less 
  adapted 
  for 
  walking. 
  To 
  the 
  Decapoda 
  also 
  belong 
  

   the 
  crabs 
  and 
  the 
  shrimps, 
  prawns, 
  and 
  crayfish. 
  The 
  crabs 
  are 
  less 
  

   related 
  to 
  the 
  lobster 
  than 
  the 
  other 
  forms 
  mentioned, 
  and 
  may 
  be 
  

   readily 
  distinguished 
  from 
  them 
  by 
  the 
  relatively 
  great 
  breadth 
  of 
  the 
  

   body 
  and 
  the 
  small 
  size 
  of 
  the 
  abdomen 
  or 
  tail, 
  which 
  is 
  doubled 
  under 
  

   the 
  thorax 
  to 
  form 
  the 
  " 
  apron." 
  The 
  lobsters, 
  crayfish, 
  shrimps, 
  etc., 
  

   are 
  elongate 
  forms 
  with 
  the 
  tail 
  or 
  abdomen 
  very 
  large 
  and 
  extended 
  

   more 
  or 
  less 
  in 
  the 
  same 
  horizontal 
  plane 
  with 
  the 
  anterior 
  part 
  of 
  the 
  

   body. 
  The 
  lobster 
  and 
  the 
  crayfishes 
  are 
  somewhat 
  closely 
  related, 
  but 
  

   <liffer, 
  among 
  other 
  characters, 
  in 
  the 
  number 
  and 
  structure 
  of 
  the 
  gills 
  

   and 
  in 
  the 
  relative 
  size 
  of 
  the 
  flat 
  plate 
  or 
  scale 
  which 
  is 
  attached 
  at 
  

   the 
  base 
  of 
  the 
  antenn;e 
  or 
  long 
  feelers. 
  The 
  Pacific 
  Coast 
  crayfishes 
  

   have 
  18 
  gills, 
  those 
  east 
  of 
  the 
  Rocky 
  Mountains 
  have 
  17, 
  while 
  the 
  

   lobster 
  has 
  20. 
  The 
  appendage 
  of 
  the 
  antenna 
  is 
  large 
  in 
  the 
  cray- 
  

   fishes, 
  but 
  very 
  small 
  in 
  the 
  lobster. 
  Moreover, 
  the 
  crayfishes 
  rarely 
  

   exceed 
  5 
  or 
  6 
  inches 
  in 
  length, 
  while 
  the 
  adult 
  lobster 
  is 
  much 
  larger, 
  

   as 
  seen 
  in 
  the 
  markets, 
  seldom 
  measuring 
  less 
  than, 
  9 
  or 
  10 
  inches. 
  

   The 
  spiny 
  lobster, 
  the 
  "lobster" 
  of 
  the 
  Pacific 
  Coast, 
  is 
  readily 
  distin- 
  

   guished 
  from 
  the 
  crayfish 
  and 
  the 
  common 
  lobster 
  by 
  the 
  total 
  absence 
  

   of 
  great 
  claws, 
  by 
  the 
  greater 
  length 
  and 
  stoutness 
  of 
  the 
  antennne, 
  and 
  

   by 
  the 
  presence 
  of 
  large, 
  broad-based, 
  si)inous 
  processes 
  on 
  the 
  back. 
  

  

  The 
  body 
  of 
  the 
  lobster 
  is 
  divided 
  into 
  two 
  distinct 
  regions, 
  the 
  

   cephalothorax 
  and 
  abdomen. 
  The 
  former 
  consists 
  of 
  the 
  head 
  and 
  

   thorax 
  fused 
  into 
  one 
  united 
  whole. 
  That 
  portion 
  which 
  would 
  consti- 
  

   tute 
  the 
  head, 
  were 
  it 
  separate, 
  bears 
  the 
  eyes, 
  tlie 
  two 
  i^airs 
  of 
  feelers, 
  

   and 
  the 
  mouth, 
  with 
  the 
  several 
  pairs 
  of 
  modified 
  limbs 
  which 
  surround 
  

   that 
  organ 
  and 
  aid 
  in 
  tearing 
  up 
  the 
  food 
  and 
  passing 
  it 
  between 
  the 
  

   lips. 
  The 
  thoracic 
  portion 
  of 
  the 
  cephalothorax 
  is 
  furnished 
  with 
  five 
  

   pairs 
  of 
  stout 
  limbs, 
  the 
  first 
  pair 
  bearing 
  the 
  great 
  claws, 
  which 
  are 
  

   rarely 
  of 
  the 
  same 
  size 
  on 
  the 
  two 
  sides, 
  and 
  the 
  last 
  four 
  pairs 
  being 
  used 
  

   in 
  walking. 
  From 
  the 
  fact 
  that 
  this 
  portion 
  of 
  the 
  body 
  bears 
  five 
  pairs 
  

   of 
  appendages, 
  it 
  is 
  assumed 
  that 
  it 
  represents 
  five 
  fused 
  segments. 
  

  

  The 
  abdomen 
  is 
  narrower 
  than 
  the 
  cephalothorax 
  and 
  is 
  composed 
  

   of 
  six 
  separate 
  segments 
  movable 
  on 
  one 
  another. 
  In 
  the 
  female 
  the 
  

  

  229 
  

  

  