﻿Crustacea 
  of 
  Dominica. 
  7 
  

  

  Gecarcinus 
  ruricola, 
  Linn. 
  

   Gecarcinus 
  ruricola, 
  Linn., 
  Milne-Edwards, 
  loc. 
  cif. 
  p. 
  26. 
  

   One 
  specimen. 
  

  

  Sesarma 
  americana, 
  de 
  Saussure. 
  

  

  Sesarma 
  americana, 
  de 
  Saussure, 
  Mem. 
  Crust, 
  nouv. 
  du 
  Mexique 
  et 
  des 
  

   Antilles, 
  p. 
  25. 
  

  

  Ten 
  specimens 
  from 
  Laiou 
  (freshwater). 
  

  

  Pseudotelphusa 
  tenuipes, 
  sp. 
  n. 
  

  

  Carapace 
  wide 
  and 
  moderately 
  flat, 
  very 
  finely 
  but 
  not 
  

   closely 
  punctured 
  ; 
  gastric 
  region 
  slightly 
  convex 
  from 
  before 
  

   backwards 
  and 
  from 
  side 
  to 
  side, 
  furnished 
  in 
  front 
  witli 
  two 
  

   faint, 
  low, 
  slightly 
  roughened 
  epigastric 
  lobes, 
  between 
  which 
  

   runs 
  forward 
  a 
  shallow 
  median 
  sulcus 
  which 
  divides 
  into 
  two 
  

   halves 
  the 
  superior 
  frontal 
  crest. 
  Anterior 
  portion 
  of 
  the 
  

   front 
  almost 
  vertical 
  and 
  bounded 
  above 
  and 
  below 
  by 
  con- 
  

   spicuous 
  bluntly 
  denticulated 
  crests, 
  of 
  which 
  the 
  inferior 
  is 
  

   less 
  conspicuous 
  ; 
  the 
  superior 
  and 
  inferior 
  crests 
  nearly 
  

   straight 
  and 
  parallel, 
  the 
  distance 
  between 
  them 
  being 
  equal 
  

   to 
  one 
  eighth 
  of 
  the 
  greatest 
  width 
  of 
  the 
  area 
  that 
  they 
  define. 
  

   Orbits 
  large, 
  their 
  length 
  being 
  nearly 
  equal 
  to 
  two 
  thirds 
  of 
  

   their 
  width 
  and 
  to 
  half 
  the 
  width 
  of 
  the 
  frontal 
  area, 
  with 
  

   bluntly 
  denticulated 
  margins. 
  Antero-lateral 
  borders 
  of 
  the 
  

   carapace 
  evenly 
  rounded 
  and 
  conspicuously 
  dentate, 
  the 
  den- 
  

   tations 
  becoming 
  smaller 
  in 
  front 
  and 
  gradually 
  disappearing 
  

   behind. 
  Cervical 
  groove 
  well 
  marked 
  and 
  straight, 
  but 
  not 
  

   quite 
  reaching 
  the 
  margin 
  of 
  the 
  carapace 
  ; 
  the 
  gastro- 
  

   branchial 
  sulci 
  very 
  shallow 
  ; 
  the 
  branchial 
  region 
  evenly 
  

   convex, 
  the 
  cardiac 
  region 
  nearly 
  flat, 
  and 
  thecardio-branchial 
  

   sulci 
  not 
  or 
  scarcely 
  visible 
  ; 
  margin 
  of 
  the 
  carapace 
  between 
  

   the 
  posterior 
  legs 
  very 
  slightly 
  concave. 
  The 
  subhepatic 
  

   and 
  anterior 
  pleural 
  regions 
  of 
  the 
  carapace 
  smooth. 
  

  

  Chelipedes 
  sparsely 
  granular 
  or 
  tubercular, 
  unequal 
  in 
  size, 
  

   and 
  differing 
  in 
  shape. 
  

  

  Merus 
  triangular, 
  superior 
  surface 
  slightly 
  concave 
  proxi- 
  

   mally, 
  anterior 
  surface 
  nearly 
  flat, 
  inferior 
  surface 
  convex 
  ; 
  

   anterior 
  surface 
  bordered 
  below 
  by 
  a 
  conspicuous 
  series 
  of 
  

   rounded 
  tubercles 
  and 
  above 
  by 
  a 
  series 
  of 
  nine 
  or 
  ten 
  large 
  

   conical 
  teeth, 
  which 
  distally 
  increase 
  in 
  size 
  ; 
  posterior 
  edge 
  

   of 
  the 
  superior 
  surface 
  bluntly 
  toothed 
  proximally, 
  the 
  teeth 
  

   distally 
  passing 
  into 
  ridges. 
  

  

  