﻿10l4 
  Forty-seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  Amphiclina, 
  Laube. 
  1885. 
  

   Shell 
  concavo-convex, 
  subtrigonal, 
  with 
  straight 
  hinge-line, 
  

   well- 
  developed 
  cardinal 
  and 
  deltidial 
  plates. 
  Spirals 
  duplicate, 
  

   the 
  two 
  pairs 
  being 
  coextensive. 
  

  

  Figs. 
  404-406. 
  Amphiclina 
  dubia, 
  Miinster 
  (sp.). 
  

   (Fig. 
  405, 
  Bittner; 
  Figs. 
  404, 
  406, 
  Beecher.) 
  

  

  Type, 
  Amphiclina 
  dubia, 
  Munster 
  (sp.). 
  

   Distribution. 
  Triassic. 
  

  

  Koninckella, 
  Munier-Chalmas. 
  1880. 
  

   Shell 
  concavo-convex, 
  smooth. 
  Hinge-line 
  straight, 
  cardinal 
  

   area, 
  deltidial 
  plates 
  and 
  cardinal 
  process 
  well 
  developed. 
  

   Spirals 
  duplicate, 
  jugum 
  probably 
  as 
  in 
  Koninckina. 
  The 
  

  

  Figs. 
  407-409. 
  

  

  Koninckella 
  triadica, 
  Bittner. 
  

   (Bittner.) 
  

  

  volutions 
  of 
  the 
  spiral 
  cones 
  are 
  few, 
  and 
  the 
  ribbon 
  of 
  the 
  

   primary 
  coils 
  bear 
  long 
  marginal 
  spinules. 
  

  

  Type, 
  Koninckella 
  Hasina, 
  Bouchard- 
  Chantereaux 
  (sp.). 
  

  

  Distribution. 
  Lias. 
  

  

  Koninckodonta, 
  Bittner. 
  1893. 
  

   Shell 
  as 
  in 
  Koninckina 
  but 
  with 
  well-developed 
  cardinal 
  area 
  

   and 
  deltaria. 
  On 
  the 
  interior 
  of 
  the 
  pedicle- 
  valve 
  is 
  a 
  submarginal 
  

   row 
  of 
  thickened 
  tubercles 
  which 
  interlock 
  with 
  similar 
  callosities 
  

  

  72 
  

  

  