﻿Report 
  of 
  tee 
  State 
  Geologist. 
  1091 
  

  

  Zellania, 
  Moore. 
  1854. 
  

  

  Shells 
  minute, 
  subtriangular, 
  impunctate. 
  Hinge-line 
  short, 
  

   straight, 
  with 
  cardinal 
  area 
  on 
  each 
  valve. 
  Foramen 
  large, 
  

   encroaching 
  on 
  the 
  brachial 
  valve. 
  Median 
  septum 
  in 
  each 
  

   valve. 
  In 
  the 
  brachial 
  valve 
  is 
  a 
  broad 
  pustulose 
  marginal 
  area, 
  

  

  Figs. 
  639, 
  640. 
  Zellania 
  Davidsoni, 
  Moore. 
  (Davidson.) 
  

  

  the 
  inner 
  edge 
  of 
  which 
  is 
  thickened 
  into 
  a 
  ridge, 
  bilobed 
  by 
  the 
  

   median 
  septum. 
  

  

  Type, 
  Zellania 
  Davidsoni, 
  Moore. 
  

  

  Distribution. 
  Lias. 
  

  

  Gwynia, 
  King. 
  1859. 
  

   Shell 
  thin, 
  minute, 
  biconvex, 
  elongate-oval. 
  HiDge-line 
  short, 
  

   nearly 
  straight. 
  Foramen 
  large, 
  with 
  incomplete 
  deltidial 
  plates. 
  

   Interior 
  without 
  septa 
  or 
  loop. 
  Brachia 
  forming 
  an 
  uninter- 
  

  

  Figs. 
  641, 
  642. 
  Gwynia 
  capsula, 
  Jeffreys 
  (sp.) 
  . 
  (Davidson.) 
  

  

  rupted 
  circlet, 
  the 
  anterior 
  cirri 
  of 
  which 
  are 
  but 
  slightly 
  

   developed. 
  

  

  Type, 
  Gwynia 
  capsula, 
  Jeffreys 
  (sp.). 
  

  

  Distribution. 
  Kecent 
  (Lusitanian 
  Province). 
  

  

  Thecidea, 
  Defrance. 
  1822. 
  

  

  Synonym; 
  Thecidium, 
  Sowerby. 
  1824. 
  

  

  Shells 
  plano-convex, 
  elongate-oval; 
  surface 
  covered 
  with 
  

   radiating 
  rows 
  of 
  granules. 
  Pedicle-valve 
  with 
  elevated 
  beak, 
  

  

  149 
  

  

  