﻿NO. 
  irn. 
  FISfTES 
  FROM 
  COLOR 
  ADO 
  BASIN— 
  GILBERT 
  AND 
  SCOFIFLD. 
  495 
  

  

  111 
  five 
  specimens 
  examined, 
  four 
  liave 
  the 
  teeth 
  1, 
  1-4, 
  1, 
  and 
  one 
  2^ 
  

   4_4, 
  1^ 
  Avitbout 
  grinding 
  surface. 
  Tlie 
  lateral 
  line 
  is 
  median 
  and 
  about 
  

   straight, 
  with 
  seventy 
  pores 
  to 
  base 
  of 
  caudal 
  fin. 
  The 
  l)elly 
  and 
  the 
  

   back 
  ill 
  front 
  of 
  the 
  dorsal 
  are 
  destitute 
  of 
  scales. 
  Least 
  depth 
  of 
  cau- 
  

   dal 
  peduncle 
  2=^ 
  in 
  head. 
  Mouth 
  very 
  small, 
  terminal, 
  oblique; 
  the 
  lips 
  

   tlcshy. 
  The 
  maxillary 
  is 
  without 
  barbels 
  and 
  is 
  contained 
  1.^ 
  in 
  

   snout. 
  The 
  mandible 
  is 
  contained 
  a 
  little 
  less 
  thau 
  three 
  times 
  in 
  head; 
  

   premaxillary 
  not 
  protractile. 
  The 
  pectoral 
  tins 
  reach 
  two-thirds 
  dis- 
  

   tance 
  to 
  veutrals. 
  The 
  ventrals 
  reach 
  the 
  front 
  of 
  the 
  anal. 
  The 
  third 
  

   ray 
  of 
  tjie 
  anal 
  is 
  the 
  longest, 
  2^ 
  in 
  head. 
  The 
  front 
  of 
  the 
  dorsal 
  is 
  

   slightly 
  behind 
  the 
  origin 
  of 
  the 
  ventrals, 
  and 
  considerably 
  nearer 
  the 
  

   base 
  of 
  the 
  caudal 
  than 
  the 
  tip 
  of 
  the 
  snout. 
  The 
  edge 
  of 
  the 
  dorsal 
  

   fin 
  is 
  straight, 
  its 
  second 
  ray 
  longest, 
  If 
  in 
  head, 
  its 
  rudimentary 
  rays 
  

   not 
  enlarged. 
  

  

  Cohn- 
  (in 
  alcohol), 
  pale 
  gray 
  or 
  yellowish, 
  mottled 
  with 
  reddish 
  -brown 
  

   on 
  sides 
  and 
  back: 
  a 
  dark 
  elongate 
  black 
  spot 
  on 
  base 
  of 
  middle 
  cau- 
  

   dal 
  rays 
  broadening 
  posteriorly 
  into 
  a 
  vertical 
  bar, 
  which 
  follows 
  the 
  

   posterior 
  outline 
  of 
  the 
  caudal 
  fin; 
  tiiis 
  followed 
  by 
  a 
  second 
  and 
  in 
  

   some 
  by 
  a 
  third 
  fainter 
  bar 
  witli 
  lighter 
  interspaces; 
  a 
  conspicuous 
  

   white 
  patch 
  above 
  and 
  below 
  caudal 
  spot; 
  there 
  is 
  a 
  small 
  but 
  con- 
  

   spicuous 
  white 
  spot 
  under 
  the 
  first 
  rays 
  of 
  the 
  dorsal 
  and 
  one 
  under 
  

   posterior 
  end 
  of 
  dorsal, 
  the 
  two 
  encroaching 
  slightly 
  on 
  the 
  fin; 
  dorsal 
  

   with 
  two 
  broad 
  but 
  faint 
  dark 
  bars 
  parallel 
  to 
  its 
  free 
  edge. 
  Length 
  

   averages 
  2^ 
  inches. 
  

  

  11. 
  AGOSIA 
  OSCULA 
  Girard. 
  

  

  About 
  thirty 
  specimens 
  were 
  obtained 
  at 
  Chino. 
  This 
  species 
  is 
  at 
  

   once 
  distinguished 
  from 
  the 
  other 
  sjiecies 
  of 
  A(/osio 
  in 
  the 
  Colorado 
  

   Basin 
  by 
  its 
  very 
  small 
  scales 
  and 
  its 
  definite 
  lateral 
  band. 
  We 
  give 
  

   here 
  a 
  description 
  based 
  on 
  our 
  specimens, 
  as 
  there 
  is 
  no 
  good 
  current 
  

   description. 
  

  

  Head 
  4 
  in 
  length; 
  depth 
  4 
  to 
  4^; 
  eye 
  4; 
  snout 
  3J; 
  scales 
  17 
  to 
  19-80 
  

   to 
  80-15 
  to 
  17; 
  D. 
  8; 
  A. 
  7; 
  least 
  depth 
  of 
  caudal 
  peduncle 
  2^ 
  in 
  head; 
  

   teeth 
  1, 
  4-4, 
  1, 
  hooked 
  and 
  with 
  grinding 
  surface. 
  Body 
  terete 
  and 
  

   rather 
  elongate, 
  the 
  caudal 
  peduncle 
  not 
  much 
  compressed. 
  The 
  head 
  

   ta])ers 
  to 
  an 
  elongate 
  but 
  obtuse 
  snout. 
  The 
  mouth 
  is 
  slightly 
  ob- 
  

   lique; 
  the 
  lii)S 
  not 
  fleshy; 
  maxillary 
  with 
  a 
  small 
  barbel 
  at 
  its 
  tip. 
  

   Free 
  margin 
  of 
  dorsal 
  and 
  anal 
  straight. 
  The 
  front 
  of 
  the 
  dorsal 
  is 
  

   slightly 
  behind 
  the 
  origin 
  of 
  the 
  ventrals 
  and 
  midway 
  between 
  the 
  

   center 
  of 
  the 
  orbit 
  and 
  the 
  base 
  of 
  the 
  middle 
  caudal 
  rays. 
  Length 
  

   of 
  dorsal 
  2 
  in 
  head; 
  its 
  longest 
  ray 
  1^ 
  in 
  head. 
  The 
  pectorals 
  are 
  

   short, 
  reaching 
  two-thirds 
  distance 
  to 
  ventrals. 
  The 
  veutrals 
  do 
  not 
  

   (juite 
  reach 
  the 
  front 
  of 
  the 
  anal. 
  J3usky 
  olive 
  above, 
  silvery 
  below; 
  a 
  

   definite 
  dark 
  lateral 
  band 
  about 
  width 
  of 
  eye, 
  expanding 
  at 
  the 
  base 
  of 
  

   the 
  caudal 
  and 
  narrowing 
  abruptly 
  to 
  a 
  faint 
  caudal 
  spot. 
  In 
  some 
  

   specimens 
  the 
  sides 
  are 
  slightly 
  mottled 
  with 
  darker. 
  Our 
  specimens 
  

   are 
  about 
  2 
  inches 
  in 
  length. 
  

  

  