﻿CRTTSTACEA. 
  317 
  

  

  this 
  genus 
  or 
  to 
  Megamoera, 
  from 
  Port 
  Jackson, 
  5-7 
  fms. 
  (No. 
  104), 
  

   but 
  which, 
  having 
  lost 
  both 
  pairs 
  of 
  antennae 
  and 
  the 
  terminal 
  seg- 
  

   ment, 
  cannot 
  be 
  referred 
  to 
  any 
  genus 
  with 
  cei'tainty. 
  It 
  is 
  distin- 
  

   guished 
  from 
  the 
  various 
  species 
  described 
  by 
  Mr. 
  Haswell 
  by 
  the 
  

   great 
  length 
  of 
  the 
  first 
  legs, 
  which 
  exceed 
  the 
  legs 
  of 
  the 
  second 
  

   pair 
  in 
  length, 
  and 
  have 
  the 
  merus 
  considerably 
  produced 
  at 
  the 
  

   postero-distal 
  angle, 
  the 
  carpus 
  about 
  twice 
  as 
  long 
  as 
  the 
  propus 
  

   and 
  truncated 
  at 
  its 
  distal 
  end, 
  propus 
  posteriorly 
  arcuated, 
  dactyl 
  

   about 
  half 
  as 
  long 
  as 
  the 
  propus 
  : 
  the 
  legs 
  of 
  the 
  second 
  pair 
  have 
  the 
  

   merus 
  short, 
  carpus 
  more 
  than 
  half 
  as 
  long 
  as 
  the 
  palm 
  and 
  trun- 
  

   cated 
  at 
  its 
  distal 
  extremity 
  ; 
  palm 
  or 
  propus 
  considerably 
  enlarged, 
  

   its 
  distal 
  margin 
  oblique 
  and 
  nearly 
  straight, 
  defined 
  at 
  the 
  postero- 
  

   distal 
  angle 
  by 
  a 
  small 
  spine, 
  and 
  with 
  a 
  truncated 
  lobe 
  or 
  tooth 
  

   nearer 
  the 
  base 
  of 
  the 
  dactylus, 
  which 
  is 
  strongly 
  arcuated 
  and 
  

   does 
  not 
  reach 
  quite 
  to 
  the 
  postero-distal 
  angle 
  of 
  the 
  palm. 
  The 
  

   coxae 
  of 
  the 
  four 
  anterior 
  legs 
  are 
  deeper 
  than 
  the 
  segments 
  with 
  

   which 
  they 
  are 
  articulated. 
  The 
  three 
  posterior 
  legs 
  slender, 
  with 
  

   the 
  basus-joints 
  little 
  dilated 
  and 
  posteriorly 
  entire, 
  the 
  merus- 
  

   joints 
  not 
  distally 
  produced 
  into 
  lobes 
  or 
  teeth. 
  The 
  uropoda 
  are 
  

   biramose, 
  the 
  rami 
  subequal, 
  those 
  of 
  the 
  posterior 
  pair 
  very 
  small, 
  

   not 
  foliaceous. 
  The 
  segments 
  of 
  the 
  body 
  are 
  without 
  teeth, 
  spines, 
  

   or 
  spinules. 
  The 
  coloration 
  (in 
  spirit) 
  whitish, 
  the 
  body 
  covered 
  

   with 
  numerous 
  small 
  black 
  dots. 
  

  

  In 
  the 
  form 
  of 
  the 
  anterior 
  legs 
  and 
  in 
  the 
  coloration 
  it 
  resembles 
  

   Amphithoe 
  setosa, 
  Haswell, 
  from 
  Botany 
  Bay, 
  but 
  diff'ers 
  in 
  the 
  form 
  

   of 
  the 
  palm 
  of 
  the 
  second 
  leg, 
  and, 
  I 
  suppose, 
  of 
  the 
  posterior 
  

   uropoda. 
  

  

  7. 
  Megamcera 
  suensis, 
  Haswell 
  ? 
  

  

  As 
  Mr. 
  Haswell's 
  description 
  is 
  very 
  short 
  and 
  our 
  specimens 
  differ 
  

   slightly 
  from 
  his 
  figure 
  in 
  the 
  form 
  of 
  the 
  second 
  legs, 
  I 
  append 
  the 
  

   following 
  description: 
  — 
  Body 
  rather 
  robust; 
  head 
  with 
  a 
  small 
  

   lateral 
  tooth 
  behind 
  the 
  antero-lateral 
  angles. 
  Coxne 
  of 
  the 
  first 
  

   four 
  thoracic 
  limbs 
  deeper 
  than 
  their 
  respective 
  body-segments, 
  the 
  

   first 
  pair 
  not 
  much 
  prolonged 
  at 
  the 
  antero-lateral 
  angles, 
  which 
  are 
  

   rounded 
  or 
  subacute. 
  The 
  last 
  thoracic 
  segment 
  and 
  the 
  first 
  and 
  

   second 
  postabdominal 
  segments 
  have 
  their 
  posterior 
  margins 
  armed 
  

   with 
  two 
  small 
  dorsal 
  spines 
  ; 
  the 
  thii'd 
  is 
  dorsally 
  eraarginate 
  but 
  

   without 
  spines 
  ; 
  the 
  fourth 
  has 
  its 
  posterior 
  and 
  dorsal 
  margins 
  

   armed 
  with 
  two 
  strong 
  triangulate 
  acute 
  lobes 
  or 
  teeth. 
  The 
  first 
  

   and 
  second 
  postabdominal 
  segments 
  have 
  a 
  small 
  spinule 
  at 
  their 
  

   postero-lateral 
  angles 
  ; 
  the 
  third 
  segment 
  has 
  its 
  postero-lateral 
  

   angles 
  truncated 
  and 
  armed 
  witli 
  three 
  to 
  five 
  teeth 
  ; 
  the 
  lobes 
  of 
  

   the 
  terminal 
  segment, 
  which 
  are 
  subcylindrical, 
  are 
  tipped 
  with 
  a 
  

   few 
  setae. 
  The 
  eyes 
  are 
  oval, 
  black. 
  The 
  antennae 
  are 
  somewhat 
  

   hairy 
  ; 
  the 
  superior 
  antennae 
  are 
  broken, 
  but 
  exceed 
  the 
  head 
  and 
  

   thoracic 
  segments 
  in 
  length 
  ; 
  the 
  basal 
  peduncular 
  joints 
  are 
  thicker 
  

   and 
  somewhat 
  shorter 
  than 
  the 
  second 
  joints 
  ; 
  the 
  third 
  joints 
  very 
  

   short 
  ; 
  the 
  slender 
  accessory 
  flagellum 
  is 
  composed 
  of 
  three 
  rather 
  

  

  