﻿PLATE 
  IV. 
  

  

  Thalassina 
  scorpionoides, 
  branchise 
  (p. 
  19). 
  

  

  Fig. 
  1. 
  Pereion, 
  showing 
  the 
  form 
  and 
  arrangement 
  of 
  the 
  branchiae 
  ; 
  lateral 
  wall 
  of 
  

   the 
  carapace 
  removed. 
  

  

  ,, 
  h. 
  First 
  gnathopod 
  with 
  rudimentary 
  mastigobranchia, 
  with 
  podobranchia 
  and 
  

   arthrobranchia 
  attached 
  ; 
  h", 
  arthrobranehial 
  plume 
  (detached) 
  ; 
  enlarged. 
  

  

  „ 
  i. 
  Second 
  gnathopod 
  with 
  rudimentary 
  mastigobranchia, 
  with 
  podobranchia 
  

   attached 
  ; 
  i", 
  arthrobranehial 
  plimie 
  detached, 
  showing 
  the 
  under 
  side 
  ; 
  

   enlarged. 
  

  

  „ 
  k. 
  Coxa 
  of 
  first 
  pereiopod 
  with 
  rudimentary 
  mastigobrauchial 
  lash, 
  with 
  the 
  

   podobranchial 
  plume 
  attached 
  ; 
  //', 
  anterior 
  arthrobranchia 
  detached, 
  

   showing 
  under 
  side 
  ; 
  k"', 
  posterior 
  arthrobranchia, 
  showing 
  upper 
  surface 
  ; 
  

   ^"', 
  under 
  surface 
  of 
  the 
  base 
  of 
  the 
  same 
  ; 
  enlarged. 
  

  

  