﻿A 
  NEW 
  CRAYFISH 
  FROM 
  TEXAS 
  — 
  HOBBS 
  225 
  

  

  with 
  a 
  row 
  of 
  setiferous 
  puiictations 
  along 
  inner 
  margins 
  of 
  lateral 
  

   ridges 
  ; 
  rostral 
  ridges 
  not 
  much 
  inflated 
  and 
  extend 
  cephalad 
  to 
  apex 
  

   of 
  rostrum. 
  Subrostral 
  ridges 
  weak. 
  Postorbital 
  ridges 
  low 
  and 
  

   terminate 
  cephalad 
  without 
  a 
  spine. 
  Suborbital 
  angle 
  absent. 
  

   Branchiostegal 
  spines 
  minute. 
  

  

  Surface 
  of 
  carapace 
  punctate 
  dorsad 
  and 
  slightly 
  granulate 
  laterad. 
  

  

  Abdomen 
  slightly 
  shorter 
  than 
  carapace 
  (25.5-26.8 
  mm.). 
  

  

  Cephalic 
  section 
  of 
  telson 
  with 
  one 
  spine 
  in 
  the 
  right 
  and 
  two 
  in 
  

   the 
  left 
  caudolateral 
  corners. 
  

  

  Epistome 
  with 
  cephalolateral 
  margins 
  rounded. 
  No 
  cephalomedian 
  

   projection. 
  

  

  Eyes 
  normal. 
  

  

  Antennules 
  of 
  the 
  usual 
  form; 
  a 
  spine 
  present 
  on 
  ventral 
  side 
  of 
  

   basal 
  segment. 
  

  

  Antennae 
  broken 
  (see 
  description 
  for 
  morphotypic 
  male). 
  Anten- 
  

   nal 
  scale 
  small 
  (fig. 
  17, 
  ^) 
  ; 
  outer 
  distal 
  portion 
  bearing 
  a 
  strong 
  spine; 
  

   lamellar 
  portion 
  comparatively 
  broad, 
  broadest 
  distad 
  of 
  middle 
  ; 
  inner 
  

   margin 
  rounded. 
  

  

  First 
  left 
  pereiopod 
  (dactyl 
  on 
  right 
  pereiopod 
  broken) 
  strongly 
  

   depressed, 
  palm 
  slightly 
  inflated. 
  Fingers 
  only 
  slightly 
  gaping 
  with 
  

   tip 
  of 
  dactyl 
  passing 
  beneath 
  tip 
  of 
  propodus, 
  when 
  fingers 
  are 
  brought 
  

   together, 
  to 
  a 
  greater 
  degree 
  than 
  in 
  most 
  crayfishes. 
  Hand 
  punctate 
  

   above 
  and 
  below 
  ; 
  mesial 
  margin 
  with 
  a 
  row 
  of 
  six 
  or 
  seven 
  well-defined 
  

   tubercles 
  subtended 
  dorsad 
  by 
  a 
  weaker 
  row 
  of 
  five 
  tubercles. 
  Outer 
  

   margin 
  of 
  hand 
  with 
  a 
  distinct 
  ridge. 
  One 
  tubercle 
  present 
  along 
  

   articulation 
  of 
  movable 
  finger 
  on 
  lower 
  surface 
  of 
  hand. 
  

  

  Opposable 
  margin 
  of 
  dactyl 
  of 
  first 
  left 
  pereiopod 
  with 
  a 
  single 
  row 
  

   of 
  minute 
  denticles 
  along 
  distal 
  third, 
  and 
  a 
  row 
  of 
  seven 
  tubercles, 
  

   third 
  from 
  base 
  the 
  largest, 
  on 
  proximal 
  two-thirds. 
  An 
  excision 
  

   occurs 
  just 
  proximad 
  of 
  the 
  largest 
  tubercle. 
  A 
  distinct 
  submedian 
  

   ridge 
  flanked 
  on 
  either 
  side 
  by 
  a 
  row 
  of 
  setiferous 
  punctations 
  present 
  

   on 
  upper 
  surface 
  of 
  dactyl. 
  Mesial 
  margin 
  with 
  a 
  row 
  of 
  10 
  tubercles 
  

   along 
  basal 
  two-thirds 
  and 
  5 
  setiferous 
  punctations 
  on 
  distal 
  third 
  ; 
  a 
  

   row 
  of 
  5 
  smaller 
  tubercles 
  on 
  proximal 
  fourth 
  immediately 
  above 
  the 
  

   larger 
  tubercles 
  just 
  mentioned. 
  Lower 
  surface 
  of 
  dactyl 
  with 
  a 
  sub- 
  

   median 
  ridge 
  flanked 
  proximally 
  by 
  a 
  row 
  of 
  setiferous 
  punctations 
  on 
  

   either 
  side. 
  

  

  Opposable 
  margin 
  of 
  immovable 
  finger 
  of 
  first 
  left 
  pereiopod 
  with 
  a 
  

   single 
  row 
  of 
  minute 
  denticles 
  along 
  distal 
  third, 
  and 
  a 
  row 
  of 
  five 
  

   tubercles, 
  the 
  proximal 
  two 
  the 
  largest 
  on 
  proximal 
  two-thirds 
  (in 
  

   some 
  specimens 
  there 
  is 
  a 
  small 
  tubercle 
  proximal 
  to 
  the 
  more 
  proxim^al 
  

   large 
  one) 
  ; 
  a 
  distinct 
  ridge 
  present 
  from 
  base 
  of 
  finger 
  to 
  second 
  large 
  

   tubercle. 
  Upper 
  surface 
  with 
  a 
  submedian 
  ridge 
  flanked 
  on 
  each 
  side 
  

   by 
  a 
  row 
  of 
  setiferous 
  punctations 
  with 
  a 
  number 
  of 
  very 
  deep 
  ones 
  

   laterad 
  of 
  base. 
  Lateral 
  margin 
  keeled 
  with 
  a 
  row 
  of 
  setiferous 
  

  

  