﻿988 
  Forty- 
  seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  and 
  terminates 
  at 
  the 
  junction 
  of 
  the 
  lateral 
  branches 
  in 
  a 
  short, 
  

   horizontal 
  process. 
  

  

  External 
  surface 
  of 
  the 
  valves 
  covered 
  with 
  numerous 
  radiat- 
  

   ing 
  plications; 
  occasionally 
  smooth. 
  Shell-substance 
  fibrous, 
  

   impunctate. 
  

  

  Type, 
  Uncites 
  gryphus, 
  Schlotheim 
  (sp.). 
  Stringocephalus 
  

   limestone 
  (Middle 
  Devonian). 
  

  

  Uncinella, 
  Waagen. 
  1883. 
  

   (Plate 
  37, 
  figs. 
  23-25.) 
  

  

  Shells 
  with 
  a 
  general 
  external 
  resemblance 
  to 
  Ketzia. 
  The 
  

   valves 
  are 
  more 
  or 
  less 
  finely 
  plicated 
  ; 
  no 
  sinus 
  or 
  median 
  fold 
  

   developed 
  ; 
  the 
  hinge-line 
  is 
  curved 
  ; 
  the 
  beak 
  full 
  and 
  strongly 
  

   incurved, 
  provided 
  with 
  a 
  distant 
  deltarium 
  ; 
  apex 
  truncated 
  by 
  

   a 
  large 
  oval 
  foramen. 
  

  

  The 
  shell 
  bears 
  spirals 
  of 
  the 
  same 
  general 
  disposition 
  as 
  in 
  

   B-etzia 
  or 
  Uncites, 
  but 
  neither 
  the 
  jugum 
  nor 
  the 
  mode 
  of 
  junc- 
  

   tion 
  of 
  the 
  primary 
  lamellae 
  with 
  the 
  crura 
  is 
  known. 
  In 
  the 
  

   pedicle- 
  valve 
  below 
  the 
  apex 
  of 
  the 
  beak, 
  there 
  is 
  an 
  excavated, 
  

   small 
  but 
  very 
  distinct 
  deltarium; 
  its 
  composition 
  of 
  two 
  pieces 
  

  

  Fig. 
  362. 
  Fig. 
  363. 
  

  

  Interior 
  cardinal 
  region 
  of 
  pedicle- 
  and 
  brachial 
  valves 
  of 
  Uncinella 
  indica, 
  Waagen. 
  (Waagen 
  ) 
  

  

  has 
  not, 
  however, 
  been 
  made 
  out. 
  It 
  does 
  not 
  reach 
  to 
  the 
  hinge 
  

   line, 
  but 
  is 
  cut 
  out 
  below 
  for 
  the 
  reception 
  of 
  the 
  apex 
  of 
  the 
  

   small 
  valve. 
  Hinge-teeth 
  long 
  and 
  not 
  supported 
  by 
  dental 
  plates. 
  

  

  In 
  the 
  brachial 
  valve 
  the 
  apex 
  is 
  flattened, 
  and 
  no 
  cardinal 
  

   process 
  is 
  present. 
  At 
  the 
  apex 
  two 
  sharp 
  ridges 
  take 
  their 
  

   origin, 
  limiting 
  the 
  dental 
  sockets 
  on 
  the 
  other 
  side. 
  These 
  latter 
  

   are 
  elongated, 
  deep, 
  triangular. 
  There 
  is 
  no 
  hinge-plate, 
  but 
  the 
  

   crura 
  take 
  their 
  origin 
  immediately 
  at 
  the 
  apex, 
  sloping 
  strongly 
  

   toward 
  the 
  middle 
  line, 
  and 
  very 
  nearly 
  reaching 
  the 
  bottom 
  of 
  

   the 
  valve. 
  

  

  Type, 
  Uncinella 
  indica, 
  Waagen. 
  

  

  Distribution. 
  Carboniferous. 
  

  

  46 
  

  

  