﻿NO. 
  1136. 
  OBSERVATIONS 
  OX 
  THE 
  ASTACIDJi:— 
  FAXON. 
  659 
  

  

  male, 
  Form 
  II, 
  with 
  uncommonly 
  long 
  rostral 
  acumen 
  and 
  long-spined 
  

   aiitenual 
  scale. 
  The 
  epistoma 
  is 
  not 
  emarginate 
  in 
  front 
  in 
  these 
  four 
  

   specimens. 
  

  

  CAMBARUS 
  ERICHSONIANUS, 
  new 
  species. 
  

   (Plate 
  LXIV, 
  figs. 
  7-12.) 
  

  

  Male^ 
  Form 
  I. 
  — 
  Rostrum 
  of 
  moderate 
  width, 
  sides 
  parallel, 
  not 
  thick- 
  

   ened, 
  lateral 
  spines 
  minute, 
  acumen 
  reaching 
  to 
  the 
  distal 
  end 
  of 
  

   the 
  antenimlar 
  i)eduncle. 
  Carax>ace 
  cylindrical, 
  heavily 
  punctated, 
  

   lightly 
  granulate 
  and 
  ciliate 
  on 
  the 
  sides; 
  lateral 
  spines 
  well 
  devel- 
  

   ojied; 
  postorhital 
  ridges 
  armed 
  with 
  a 
  small 
  anterior 
  spine; 
  antero- 
  

   lateral 
  border 
  scarcely 
  angulated 
  below 
  the 
  eye; 
  areola 
  of 
  moderate 
  

   width, 
  but 
  little 
  longer 
  than 
  the 
  distance 
  from 
  the 
  cervical 
  groove 
  to 
  

   the 
  lateral 
  spines 
  of 
  the 
  rostrum. 
  Abdomen 
  as 
  long 
  as 
  the 
  cephalo- 
  

   thorax. 
  Epistome 
  triangular, 
  often 
  truncate 
  or 
  notched 
  in 
  front. 
  Car- 
  

   pus 
  of 
  chelipeds 
  with 
  an 
  internal 
  median 
  and 
  inferior 
  median 
  spine. 
  

   Chela 
  broad, 
  inflated, 
  setiferous, 
  fingers 
  somewhat 
  longer 
  than 
  the 
  palm; 
  

   internal 
  margin 
  of 
  palm 
  with 
  a 
  double 
  row 
  of 
  depressed 
  tubercles. 
  

   First 
  pair 
  of 
  abdominal 
  appendages 
  straight, 
  without 
  any 
  prominent 
  

   angle 
  or 
  shoulder 
  on 
  the 
  anteiior 
  border, 
  bifid, 
  the 
  two 
  branches 
  slender 
  

   and 
  acute, 
  reaching 
  forward 
  to 
  the 
  base 
  of 
  the 
  second 
  pair 
  of 
  legs. 
  

  

  In 
  the 
  second 
  form 
  of 
  the 
  male 
  the 
  first 
  pair 
  of 
  abdominal 
  appendages 
  

   are 
  thicker, 
  blunter 
  at 
  the 
  tips, 
  and 
  not 
  horny, 
  as 
  in 
  the 
  first 
  form. 
  

  

  In 
  the 
  female 
  the 
  annulus 
  ventralis 
  is 
  depressed, 
  only 
  very 
  imper- 
  

   fectly 
  bituberculate 
  in 
  front, 
  the 
  hind 
  border 
  more 
  iirominent 
  than 
  the 
  

   front 
  border, 
  the 
  central 
  fossa 
  obsolescent. 
  

  

  Dimensions 
  of 
  a 
  male, 
  Form 
  I 
  : 
  Length 
  70 
  mm. 
  ; 
  cephalo-thorax35mm. 
  ; 
  

   areola 
  11 
  mm.; 
  rostrum 
  5 
  mm.; 
  chela 
  25 
  mm.; 
  dactylus 
  15.5 
  mm.; 
  

   bieadth 
  of 
  chela 
  mm. 
  

  

  Rip 
  Roaring 
  Fork, 
  five 
  miles 
  northwest 
  of 
  Greeneville, 
  Tennessee; 
  

   Eastanaula 
  Creek, 
  Athens, 
  Tennessee; 
  Matlock 
  Spring 
  Creek, 
  near 
  

   Athens, 
  Tennessee; 
  Big 
  Cahawba 
  River, 
  Alabama. 
  (Colls. 
  U.S.i^.M. 
  

   and 
  Mus. 
  Comp. 
  Zool.) 
  

  

  In 
  large 
  males. 
  Form 
  I, 
  the 
  inner 
  branch 
  of 
  the 
  first 
  abdominal 
  

   appendages 
  is 
  somewhat 
  enlarged 
  and 
  spoon-shaped 
  at 
  the 
  tip. 
  

  

  This 
  species 
  has 
  the 
  facies 
  of 
  C. 
  spiuosns, 
  but 
  the 
  male 
  appendages 
  

   are 
  nearly 
  like 
  those 
  of 
  C 
  propinqims^ 
  although 
  the 
  rami 
  are 
  a 
  little 
  

   longer. 
  Compared 
  with 
  C. 
  spinosus, 
  the 
  rami 
  of 
  the 
  sexual 
  appendages 
  

   in 
  the 
  male. 
  Form 
  I, 
  are 
  much 
  shorter, 
  and 
  there 
  is 
  no 
  angle 
  or 
  shoulder 
  

   on 
  the 
  anterior 
  margin 
  of 
  these 
  appendages; 
  in 
  the 
  second 
  form 
  of 
  the 
  

   male 
  of 
  C. 
  ericlisoniamm 
  the 
  sexual 
  appendages 
  are 
  mnch 
  shorter 
  and 
  

   blunter 
  than 
  in 
  C. 
  spinosus, 
  and 
  the 
  two 
  rami 
  are 
  of 
  equal 
  length. 
  

   Tlie 
  female 
  of 
  C. 
  spinosns, 
  may 
  be 
  distinguished 
  from 
  the 
  present 
  species 
  

   by 
  the 
  piominent 
  annulus 
  ventralis 
  with 
  bituberculate 
  anterior 
  border 
  

   and 
  deep 
  transverse 
  central 
  fossa. 
  G. 
  propinquus^ 
  compared 
  with 
  

   C. 
  erichsonianus, 
  is 
  distinguished 
  by 
  its 
  more 
  ovoid 
  cephalo-thorax, 
  

  

  