﻿SEMIONOTID^. 
  161 
  

  

  P. 
  1594. 
  A 
  small 
  fish 
  wanting 
  the 
  candal 
  region, 
  showing 
  the 
  

   position 
  of 
  the 
  pelvic 
  fins 
  ; 
  Dumbleton. 
  Egerton 
  Coll. 
  

  

  P. 
  3624. 
  Two 
  specimens 
  of 
  the 
  abdominal 
  region, 
  one 
  also 
  ex- 
  

   hibiting 
  the 
  opercular 
  apparatus 
  and 
  pectoral 
  fin 
  ; 
  Dum- 
  

   bleton. 
  EnnisTcillen 
  Coll. 
  

  

  P. 
  7039. 
  Fragment 
  of 
  abdominal 
  squamation 
  ; 
  Dumbleton. 
  

  

  Purchased, 
  1894. 
  

  

  Tetragonolepis 
  oldhami, 
  Egerton. 
  

  

  1878. 
  Tetragonolepis 
  oldhami, 
  Sir 
  P. 
  Egerton, 
  Palseont. 
  Indica, 
  [4] 
  

   vol. 
  i. 
  pt. 
  ii. 
  p. 
  3, 
  pi. 
  ii. 
  fig. 
  1. 
  

  

  Type. 
  Fish 
  wanting 
  head 
  and 
  caudal 
  region; 
  Indian 
  Museum. 
  

   Calcutta. 
  

  

  A 
  species 
  attaining 
  a 
  length 
  of 
  about 
  0*15, 
  with 
  trunk 
  apparently- 
  

   less 
  deepened 
  than 
  in 
  the 
  type 
  ; 
  the 
  greatest 
  depth 
  of 
  that 
  portion 
  

   of 
  the 
  trunk 
  below 
  the 
  vertebral 
  axis 
  equalling 
  about 
  twice 
  that 
  of 
  

   the 
  portion 
  above 
  the 
  axis. 
  Cranial 
  roof 
  closely 
  tuberculated, 
  facial 
  

   and 
  opercular 
  bones 
  apparently 
  smooth. 
  Ventral 
  ridge-scales 
  

   tuberculated 
  and 
  sharply 
  serrated. 
  

  

  Form. 
  Sf 
  Log. 
  Lower 
  Jurassic 
  (Kota 
  Group) 
  : 
  Deccan, 
  India. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Tetragonolepis 
  drosera, 
  Egerton. 
  

  

  1852. 
  Pleurolepis, 
  sp., 
  F. 
  A. 
  Quenstedt, 
  Handb. 
  Petrefakt. 
  p. 
  215. 
  

  

  1853. 
  Tetragonolepis 
  droserus, 
  Sir 
  P. 
  Egerton, 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  

   vol. 
  ix. 
  p. 
  278, 
  pi. 
  xi. 
  fig. 
  4. 
  

  

  1858. 
  Tetragonolepis 
  cinctus, 
  F. 
  A. 
  Quenstedt, 
  Der 
  Jura, 
  p. 
  230, 
  

   pi. 
  xxix. 
  figs. 
  6, 
  7. 
  [Nearly 
  complete 
  fish 
  ; 
  Tubingen 
  University 
  

   Museum.] 
  

  

  1860. 
  Homceolepis 
  drosera, 
  A. 
  Wagner, 
  Gelehrte 
  Anzeig. 
  k. 
  bay. 
  Akad, 
  

   Wiss. 
  vol. 
  1. 
  p. 
  97. 
  

  

  Type. 
  Imperfect 
  fish 
  ; 
  British 
  Museum. 
  

  

  A 
  large 
  species, 
  attaining 
  a 
  length 
  of 
  about 
  0*3, 
  and 
  somewhat 
  

   more 
  elongated 
  than 
  the 
  type. 
  Head 
  with 
  opercular 
  apparatus 
  

   occupying 
  about 
  one-quarter 
  of 
  the 
  total 
  length; 
  the 
  external 
  

   bones 
  closely 
  granulated. 
  Scales 
  ornamented 
  with 
  numerous 
  gra- 
  

   nulations, 
  rarely 
  fused 
  into 
  short 
  rugae; 
  the 
  hinder 
  border 
  not 
  

   serrated. 
  

  

  This 
  species 
  is 
  regarded 
  by 
  Wagner 
  as 
  the 
  type 
  of 
  a 
  distinct 
  

   genus, 
  Homceolepis, 
  said 
  to 
  be 
  separated 
  from 
  Tetragonolepis 
  by 
  the 
  

   much 
  less 
  protuberant 
  character 
  of 
  the 
  ventral 
  region, 
  the 
  relatively 
  

   past 
  in. 
  m 
  

  

  