﻿376 
  On 
  neio 
  Freshwater 
  Fishes 
  from 
  Portuguese 
  Guinea. 
  

  

  Pectoral 
  spine 
  as 
  long 
  as 
  or 
  slightly 
  longer 
  than 
  head, 
  

   strongly 
  serrated 
  on 
  both 
  sides. 
  Ventral 
  reaching 
  origin 
  of 
  

   anal 
  or 
  a 
  little 
  beyond. 
  Caudal 
  deeply 
  notched, 
  upper 
  lobe 
  

   the 
  longer. 
  Caudal 
  peduncle 
  as 
  long 
  as 
  deep 
  or 
  a 
  little 
  

   deeper 
  than 
  long. 
  Dark 
  brown 
  above 
  and 
  below, 
  head, 
  body, 
  

   and 
  dorsal 
  fins 
  with 
  numerous 
  round 
  black 
  spots. 
  Young 
  

   paler 
  brown, 
  with 
  larger 
  and 
  fewer 
  black 
  spots 
  ; 
  fins 
  whitish, 
  

   with 
  large 
  black 
  spots 
  forming 
  cross-bars 
  on 
  the 
  anal 
  and 
  

   caudal. 
  

  

  Total 
  length 
  235 
  mm. 
  

  

  Numerous 
  specimens 
  from 
  the 
  Geba 
  and 
  Culufi 
  Rivers. 
  

  

  This 
  species, 
  which 
  may 
  be 
  placed 
  near 
  S. 
  nigrita, 
  C. 
  & 
  V., 
  

   and 
  melanopterus, 
  Blgr., 
  is 
  very 
  distinct 
  from 
  any 
  previously 
  

   described. 
  

  

  Tilapia 
  ansorgii. 
  

  

  Depth 
  of 
  body 
  twice 
  in 
  total 
  length, 
  length 
  of 
  head 
  3 
  times. 
  

   Head 
  If 
  times 
  as 
  long 
  as 
  broad, 
  upper 
  profile 
  slightly 
  con- 
  

   cave 
  ; 
  snout 
  as 
  long 
  as 
  broad, 
  If 
  times 
  as 
  long 
  as 
  eye 
  in 
  

   adult, 
  as 
  long 
  as 
  eye 
  in 
  young 
  ; 
  eye 
  3 
  (young) 
  to 
  4 
  times 
  in 
  

   length 
  of 
  head, 
  1 
  to 
  If 
  times 
  in 
  interorbit.al 
  width, 
  equal 
  to 
  

   depth 
  of 
  prseorbital 
  ; 
  mouth 
  extending 
  to 
  between 
  nostril 
  and 
  

   eye, 
  extremity 
  of 
  maxillary 
  exposed 
  ; 
  outer 
  teeth 
  in 
  both 
  jaws 
  

   large, 
  obtusely 
  bilobed, 
  20 
  (young) 
  to 
  38 
  in 
  upper 
  jaw, 
  

   followed 
  after 
  a 
  wide 
  interspace 
  by 
  a 
  few 
  minute 
  tricuspid 
  

   teeth 
  arranged 
  in 
  2 
  or 
  3 
  transverse 
  series 
  ; 
  5 
  or 
  6 
  series 
  of 
  

   scales 
  on 
  the 
  cheek, 
  the 
  vertical 
  diameter 
  of 
  the 
  scaly 
  part 
  

   below 
  the 
  eye 
  equal 
  to 
  diameter 
  of 
  latter. 
  Gill-rakers 
  rather 
  

   short, 
  the 
  larger 
  anvil-shaped, 
  11 
  or 
  12 
  on 
  lower 
  part 
  of 
  

   anterior 
  arch. 
  Dorsal 
  XIV-XV 
  14-15 
  ; 
  spines 
  increasing 
  in 
  

   length 
  to 
  the 
  last, 
  which 
  measures 
  % 
  to 
  § 
  length 
  of 
  head 
  ; 
  

   longest 
  soft 
  ray 
  f 
  to 
  |- 
  length 
  of 
  head. 
  Anal 
  III 
  10-11 
  ; 
  

   third 
  spine 
  longest, 
  stronger 
  but 
  shorter 
  than 
  longest 
  dorsal. 
  

   Pectoral 
  a 
  little 
  shorter 
  than 
  head, 
  not 
  reaching 
  vertical 
  of 
  

   origin 
  of 
  anal. 
  Ventral 
  produced 
  into 
  a 
  long 
  filament, 
  

   reaching 
  origin 
  of 
  anal 
  or 
  beyond. 
  Caudal 
  rounded, 
  scaly 
  all 
  

   over 
  in 
  the 
  adult. 
  Caudal 
  peduncle 
  deeper 
  than 
  long. 
  Scales 
  

   not 
  or 
  but 
  very 
  feebly 
  denticulate, 
  30-32 
  =g| 
  ; 
  lat. 
  I. 
  ~?' 
  

   Grey 
  or 
  brown, 
  with 
  seven 
  or 
  eight 
  broad 
  black 
  vertical 
  bars 
  

   descending 
  to 
  the 
  mid-ventral 
  line, 
  the 
  first 
  passing 
  through 
  

   the 
  eye, 
  the 
  last 
  on 
  the 
  caudal 
  peduncle 
  ; 
  pectoral 
  greyish, 
  

   other 
  fins 
  blackish. 
  

  

  Total 
  length 
  210 
  mm. 
  

  

  Several 
  specimens 
  from 
  the 
  Geba 
  and 
  Culufi 
  Rivers. 
  

  

  