﻿NO. 
  1131. 
  FlSHKS 
  FROM 
  COLORADO 
  BASIN— 
  GILBERT 
  AND 
  SCOFIELD. 
  407 
  

  

  as 
  head, 
  curved 
  and 
  slightly 
  longer 
  than 
  the 
  second 
  spine, 
  which 
  is 
  

   received 
  into 
  a 
  longitudinal 
  groove 
  in 
  the 
  first; 
  back 
  of 
  these 
  the 
  rays 
  

   are 
  thickened 
  and 
  ossified 
  for 
  a 
  little 
  over 
  half 
  their 
  length, 
  their 
  tips 
  

   articulated 
  and 
  issuing 
  from 
  the 
  tips 
  of 
  the 
  spines; 
  length 
  of 
  anal 
  

   1.] 
  ill 
  head, 
  with 
  one 
  rudimentary 
  and 
  ten 
  developed 
  rays; 
  pectoral 
  

   reaching 
  ventrals, 
  their 
  rays 
  slightly 
  ossified 
  at 
  base; 
  veiitrals 
  reach- 
  

   ing 
  vent, 
  the 
  first 
  ray 
  thickened 
  and 
  ossified 
  for 
  half 
  its 
  length, 
  the 
  

   remaining 
  rays 
  developed 
  as 
  six 
  shar}) 
  fiat 
  spines 
  which 
  fokl 
  together 
  

   like 
  a 
  fan 
  when 
  the 
  fin 
  is 
  closed. 
  From 
  the 
  posterior 
  side 
  of 
  each 
  si)ine 
  

   and 
  from 
  just 
  below 
  its 
  tip 
  an 
  articulated 
  ray 
  issues, 
  the 
  first 
  extend- 
  

   ing 
  beyond 
  its 
  spine 
  for 
  one-fourth 
  length 
  of 
  latter, 
  the 
  others 
  success- 
  

   ively 
  shorter; 
  the 
  last 
  scarcelj^ 
  projecting; 
  osseous 
  portion 
  of 
  last 
  ray 
  

   joiiu 
  d 
  for 
  its 
  whole 
  length 
  by 
  a 
  membrane 
  to 
  the 
  abdomen; 
  caudal 
  

   forked 
  for 
  half 
  its 
  length. 
  

  

  .ALouth 
  moderate, 
  horizontal, 
  lower 
  jaw 
  included; 
  maxillary 
  extend- 
  

   ing 
  to 
  front 
  of 
  orbit, 
  with 
  a 
  small 
  barbel 
  at 
  its 
  tip; 
  length 
  of 
  mandible 
  

   equal 
  to 
  distance 
  from 
  tip 
  of 
  snout 
  to 
  center 
  of 
  orbit, 
  the 
  space 
  

   between 
  them 
  papillose 
  and 
  spongy. 
  Nasals 
  elevated, 
  the 
  muzzle 
  

   slightly 
  depressed. 
  Lateral 
  line 
  deflected 
  opposite 
  the 
  dorsal, 
  not 
  quite 
  

   complete, 
  about 
  thirty-five 
  pores 
  to 
  opposite 
  front 
  of 
  anal; 
  rudiments 
  

   of 
  scales 
  can 
  be 
  seen 
  above 
  lateral 
  line, 
  more 
  numerous 
  in 
  front 
  of 
  

   dorsal 
  Color 
  pure 
  silvery, 
  yellowish 
  beneath; 
  dorsal 
  region 
  very 
  

   finely 
  punctulate; 
  peritoneum 
  and 
  gill 
  cavity 
  light 
  silvery. 
  

  

  15. 
  MEDA 
  FULGIDA 
  Girard. 
  

  

  This 
  species 
  was 
  found 
  extremely 
  abundant 
  in 
  the 
  upper 
  course 
  of 
  

   the 
  Rio 
  Verde, 
  near 
  Chino, 
  Arizona, 
  and 
  was 
  taken 
  also 
  in 
  the 
  Salt 
  

   River 
  at 
  Tempe. 
  It 
  had 
  previously 
  been 
  taken 
  only 
  in 
  the 
  Rio 
  San 
  

   Pedro. 
  Following 
  is 
  a 
  description 
  of 
  our 
  specimens: 
  

  

  Head 
  4 
  in 
  lengtli 
  ; 
  depth 
  oi; 
  eye 
  3i 
  in 
  head, 
  e(jual 
  to 
  snout 
  and 
  to 
  

   interorbital 
  width. 
  Least 
  dei)th 
  of 
  caudal 
  peduncle 
  3^ 
  in 
  head, 
  equal- 
  

   ing 
  diameter 
  of 
  eye. 
  D. 
  II, 
  C, 
  counting 
  last 
  divided 
  ray 
  as 
  one; 
  A. 
  8, 
  

   9, 
  or 
  10, 
  usually 
  9. 
  Front 
  of 
  dorsal 
  behind 
  origin 
  of 
  ventral 
  consider- 
  

   ably 
  nearer 
  base 
  of 
  caudal 
  than 
  tip 
  of 
  snout. 
  Tlie 
  character 
  of 
  dorsal 
  

   rays 
  is 
  the 
  same 
  as 
  iu 
  PliKjopterus 
  (oy/entisshnii,s, 
  the 
  first 
  spine 
  curved 
  

   nearer 
  its 
  tip 
  than 
  in 
  the 
  latter, 
  the 
  second 
  spine 
  shorter 
  than 
  the 
  

   first; 
  first 
  spine 
  IJ 
  m 
  head, 
  longer 
  than 
  base 
  of 
  fin, 
  which 
  is 
  contained 
  

   twice 
  in 
  head; 
  anal 
  l-f 
  in 
  head; 
  pectorals 
  reach 
  two 
  thirds 
  distance 
  

   to 
  vent; 
  the 
  rays 
  osseous 
  at 
  base; 
  ventrals 
  reaching 
  almost 
  to 
  vent, 
  

   and 
  structurally 
  the 
  same 
  as 
  in 
  /*. 
  ar<ienUssi 
  mus 
  ; 
  caudal 
  forked 
  for 
  a 
  

   little 
  less 
  than 
  half 
  its 
  length, 
  the 
  lobes 
  rounded. 
  Mouth 
  moderate, 
  

   terminal, 
  slightly 
  oblique, 
  the 
  lower 
  jaw 
  included; 
  mandible 
  reaching 
  

   vertical 
  from 
  center 
  of 
  pupil; 
  maxillary 
  reaching 
  front 
  of 
  pupil, 
  with- 
  

   out 
  barbel. 
  The 
  teeth 
  were 
  examined 
  in 
  ten 
  specimens, 
  eight 
  having 
  

   them 
  1, 
  4-4, 
  1; 
  one 
  1*, 
  4-4, 
  1, 
  and 
  one 
  1, 
  4-5, 
  1. 
  Lateral 
  line 
  gradually 
  

   descending 
  backward 
  to 
  beneath 
  the 
  dorsal, 
  where 
  it 
  bends 
  rather 
  

   Proc. 
  N. 
  M. 
  vol 
  XX 
  32 
  

  

  