﻿[83] 
  

  

  DECAPODA 
  FROM 
  ALBATROSS 
  DREDGINGS. 
  

  

  687 
  

  

  pax, 
  excluding 
  the 
  rostrum 
  ; 
  the 
  proximal 
  segment 
  of 
  the 
  mandibular 
  

   palpus 
  is 
  larger 
  and 
  much 
  broader 
  than 
  the 
  distal, 
  which 
  is 
  long 
  and 
  

   narrow 
  ; 
  the 
  endognath 
  of 
  the 
  first 
  maxilla 
  is 
  short 
  and 
  unsegmented; 
  

   the 
  second 
  gnathopod 
  and 
  the 
  first, 
  second, 
  third, 
  and 
  fourth 
  peraeopods 
  

   have 
  well-developed 
  epipods 
  ; 
  and 
  there 
  is, 
  either 
  side, 
  a 
  pleurobranchia 
  

   on 
  the 
  fourteenth 
  somite 
  and 
  two 
  arthrobranchiae 
  on 
  the 
  thirteenth. 
  

   The 
  branchio-epipodal 
  formula 
  is 
  as 
  follows 
  : 
  

  

  The 
  genus 
  thus 
  differs 
  from 
  both 
  Penceus 
  and 
  Parapenceus 
  in 
  the 
  

   elongated 
  antennular 
  flagella, 
  the 
  form 
  of 
  the 
  mandibular 
  palpus, 
  and 
  

   in 
  the 
  presence 
  of 
  two 
  arthobranchiae 
  and 
  an 
  epipod 
  on 
  either 
  side 
  of 
  

   the 
  thirteenth 
  somite; 
  it 
  agrees 
  with 
  Penceus 
  and 
  differs 
  from 
  Para- 
  

   penceus 
  in 
  having 
  an 
  epipod 
  at 
  the 
  base 
  of 
  the 
  second 
  gnathopod; 
  and 
  

   it 
  agrees 
  with 
  Parapenceus 
  and 
  differs 
  from 
  Penceus 
  in 
  having 
  the 
  endo- 
  

   gnath 
  of 
  the 
  first 
  maxilla 
  short 
  and 
  uusegmented. 
  

  

  The 
  species 
  examined 
  further 
  agree 
  in 
  having 
  autenual, 
  hepatic, 
  and 
  

   branchiostegal 
  spines, 
  a 
  fourth 
  spine 
  back 
  of 
  the 
  orbit, 
  and 
  small 
  epi- 
  

   pods 
  at 
  the 
  bases 
  of 
  all 
  the 
  peraeopods. 
  

  

  Hymenopen^us 
  debilis 
  Smith. 
  

  

  Bull.Mus. 
  Couip.Zool., 
  x, 
  p. 
  91, 
  pi. 
  15, 
  figs. 
  6-11, 
  pi. 
  16, 
  figs. 
  1-3, 
  1882. 
  

   (Plate 
  XVI, 
  Fig. 
  7.) 
  

   Specimens 
  examined. 
  

  

  All 
  these 
  specimens 
  are 
  small 
  and 
  in 
  bad 
  condition, 
  but 
  are 
  apparently 
  

   specifically 
  identical 
  with 
  those 
  originally 
  described 
  from 
  the 
  Blake 
  col- 
  

   lection. 
  The 
  appendages 
  of 
  the 
  second 
  pleopods 
  in 
  the 
  small 
  male 
  from 
  

   station 
  2187 
  are 
  very 
  different 
  from 
  those 
  of 
  IT. 
  mior 
  ops 
  or 
  robustus, 
  and, 
  

   though 
  they 
  are 
  very 
  likely 
  not 
  fully 
  developed, 
  are 
  probably 
  sufficiently 
  

  

  