﻿238 
  Transactions. 
  — 
  Zoology. 
  

  

  directed 
  posteriorly. 
  Posterior 
  pair 
  of 
  pleopoda 
  biraraous, 
  Telson 
  simple, 
  

   divided, 
  squamiform. 
  

  

  13. 
  Dexaniine 
  pacifoca, 
  nov. 
  sp. 
  Fig. 
  B.4. 
  

  

  Cephalon 
  without 
  a 
  rostrum, 
  but; 
  produced 
  into 
  an 
  acute 
  tooth 
  between 
  

   the 
  bases 
  of 
  the 
  antennge. 
  Pereion 
  smooth 
  ; 
  segments 
  of 
  pleon 
  dorsally 
  

   and 
  posteriorly 
  three-spined, 
  and 
  with 
  the 
  inferior 
  margin 
  produced 
  

   posteriorly 
  into 
  an 
  acute 
  tooth. 
  Eyes 
  ovate-reniform. 
  Superior 
  antennae 
  

   about 
  as 
  long 
  as 
  the 
  body; 
  basal 
  joint 
  stout, 
  with 
  a 
  spine 
  at 
  its 
  lower 
  

   anterior 
  margin 
  ; 
  second, 
  joint 
  about 
  twice 
  as 
  long 
  ; 
  flagellum 
  40-50- 
  

   jointed. 
  Inferior 
  antennaB 
  about 
  two-thirds 
  as 
  long 
  as 
  superior, 
  slender 
  ; 
  

   basal 
  joint 
  very 
  short 
  ; 
  second 
  joint 
  as 
  long 
  as 
  corresponding 
  joint 
  of 
  upper 
  

   antennae; 
  ultimate 
  joint 
  of 
  peduncle 
  just 
  half 
  as 
  long; 
  flagellum 
  about 
  

   25-30-jointed. 
  Gnathopoda 
  of 
  first 
  pair 
  larger 
  than 
  second, 
  with 
  the 
  

   inferior 
  margin 
  of 
  the 
  carpus 
  and 
  propodos 
  crenulated 
  and 
  hairy; 
  palm 
  

   oblique, 
  dactylos 
  nearly 
  straight. 
  Second 
  gnathopoda 
  similarly 
  toothed 
  and 
  

   hairy 
  ; 
  propodos 
  shorter, 
  dilated, 
  with 
  two 
  spines 
  at 
  the 
  base 
  of 
  the 
  palm 
  ; 
  

   dactylos 
  curved. 
  Pereiopoda 
  slender, 
  thickly 
  setose, 
  all 
  having 
  the 
  dactylos 
  

   directed 
  posteriorly, 
  except 
  the 
  last 
  pair, 
  which 
  also 
  are 
  much 
  the 
  longest. 
  

   Penultimate 
  pair 
  of 
  pleopoda 
  reaching 
  to 
  extremity 
  of 
  ultimate 
  ; 
  ante- 
  

   penultimate 
  much 
  shorter. 
  Telson 
  bifid, 
  apex 
  of 
  each 
  division 
  with 
  two 
  or 
  

   three 
  small 
  teeth 
  and 
  a 
  few 
  short 
  hairs. 
  Length 
  -25 
  inch. 
  (No 
  locality). 
  

  

  Genus 
  Atjlns, 
  Leach, 
  Zool. 
  Miscel., 
  ii., 
  pi. 
  69; 
  Edwards, 
  Hist, 
  des 
  Crust., 
  

  

  iii., 
  p. 
  67 
  ; 
  8. 
  Bate, 
  Brit. 
  Mus. 
  Cat. 
  Amphip. 
  Crust., 
  p. 
  133. 
  

  

  Iphimedia, 
  Dana, 
  U. 
  S. 
  Explor. 
  Esped., 
  p. 
  926. 
  

  

  Animal 
  compressed. 
  Antenna 
  subequal 
  ; 
  superior 
  without 
  a 
  secondary 
  

   appendage. 
  Mandibles 
  with 
  an 
  appendage. 
  MaxilHpeds 
  unguiculate, 
  having 
  

   a 
  squamiform 
  plate 
  developed 
  from 
  the 
  bases 
  and 
  ischium. 
  Gnathopoda 
  

   subchelate. 
  Pereiopoda 
  subequal. 
  Posterior 
  pleopoda 
  biramous. 
  Telson 
  

   single, 
  squamiform, 
  divided. 
  

  

  Differs 
  from 
  Dexamine 
  in 
  having 
  the 
  third 
  joint 
  of 
  the 
  peduncle 
  of 
  the 
  

   upper 
  antenna 
  distinguishable 
  from 
  the 
  flagellum, 
  and 
  in 
  having 
  an 
  

   appendage 
  to 
  the 
  mandibles. 
  

   14. 
  Atylm 
  dania, 
  nov. 
  sp. 
  Fig. 
  C.l. 
  

  

  Cephalon 
  produced 
  into 
  a 
  short 
  rostrum. 
  Segments 
  of 
  the 
  pleon 
  

   slightly 
  elevated 
  posteriorly, 
  fourth 
  segment 
  with 
  a 
  deep 
  dorsal 
  sinus, 
  none 
  

   prolonged 
  into 
  teeth; 
  margins 
  smooth. 
  Eyes 
  large, 
  round, 
  black. 
  Superior 
  

   antenna; 
  about 
  a 
  third 
  shorter 
  than 
  the 
  inferior; 
  joints 
  of 
  the 
  peduncle 
  

   short, 
  subequal, 
  produced 
  into 
  three 
  teeth 
  on 
  the 
  lower 
  margin; 
  flagellum 
  

   with 
  over 
  25 
  articulations, 
  which 
  are 
  broader 
  than 
  long, 
  every 
  third 
  or 
  

   fourth 
  joint 
  produced 
  on 
  its 
  inferior 
  margin 
  into 
  a 
  tubercle, 
  bearing 
  several 
  

   long 
  cilia 
  and 
  a 
  crown 
  of 
  short 
  hairs. 
  Inferior 
  antennge 
  half 
  as 
  long 
  as 
  

  

  