﻿PLATE 
  LVI. 
  

  

  Benthesicymus 
  iridescens 
  (p. 
  335). 
  

  

  Fig. 
  1. 
  Outer 
  branch 
  of 
  sixth 
  pleopod 
  ; 
  arterial 
  vessels, 
  red 
  ; 
  venous, 
  blue 
  ; 
  nerve- 
  

   filaments, 
  yellow; 
  muscles, 
  brown. 
  

  

  „ 
  2. 
  Ventral 
  nerve-cord 
  of 
  same. 
  

  

  Eucopia 
  australis. 
  

   ,, 
  3. 
  Ventral 
  nerve-cord. 
  

  

  Sergestes 
  atlanticus. 
  

   ,, 
  4. 
  Arrangement 
  of 
  muscles 
  in 
  the 
  sixth 
  somite 
  of 
  the 
  pleon. 
  

  

  