﻿360 
  Forty-seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  tubercled 
  organ 
  in 
  Coccosteus 
  (Brachydirus) 
  of 
  somewhat 
  similar 
  

   aspect 
  to 
  that 
  represented 
  as 
  a 
  mandible 
  by 
  Lydekker 
  but 
  

   regarded 
  as 
  a 
  steering 
  organ 
  or 
  the 
  spine 
  of 
  a 
  pectoral 
  fin. 
  New- 
  

   berry 
  makes 
  a 
  statement 
  in 
  regard 
  to 
  the 
  mandible 
  of 
  Coccosteus 
  

   which 
  is 
  more 
  to 
  the 
  point. 
  He 
  says 
  : 
  * 
  "It 
  has 
  been 
  supposed 
  

   that 
  the 
  dentition 
  of 
  Coccosteus 
  and 
  that 
  of 
  Dinicthys 
  were 
  

   radically 
  different, 
  .but 
  I 
  have 
  learned 
  that 
  they 
  were 
  very 
  much 
  

   alike. 
  The 
  mandibles 
  of 
  Coccosteus 
  that 
  have 
  been 
  figured 
  are 
  

   all 
  imperfect, 
  the 
  anterior 
  ends 
  being 
  crushed, 
  distorted 
  or 
  

   wanting 
  ; 
  yet, 
  as 
  I 
  have 
  mentioned 
  elsewhere, 
  I 
  recently 
  found 
  

   in 
  the 
  South 
  Kensington 
  museum 
  a 
  mandible 
  of 
  Coccosteus 
  which 
  

   was 
  a 
  perfect 
  miuiature 
  of 
  that 
  of 
  Dinicthys, 
  being 
  spatulate 
  

   posteriorly 
  and 
  having 
  the 
  anterior 
  end 
  turned 
  up 
  to 
  form 
  a 
  

   conspicuous 
  denticle." 
  This 
  passage 
  omits 
  to 
  state 
  to 
  which 
  of 
  

   the 
  two 
  types 
  of 
  Dinicthys 
  mandible 
  the 
  specimen 
  referred 
  to 
  

   conforms. 
  Hugh 
  Miller, 
  in 
  the 
  fourth 
  edition 
  of 
  " 
  The 
  Old 
  Eed 
  

   Sandstone," 
  after 
  demonstrating 
  in 
  description 
  and 
  figure 
  that 
  

   the 
  mandible 
  of 
  Coccosteus 
  is 
  denticulated, 
  further 
  showed 
  (foot- 
  

   note 
  to 
  page 
  52) 
  that 
  there 
  is 
  also 
  a 
  row 
  of 
  three 
  to 
  five 
  teeth 
  on 
  

   each 
  ramus 
  along 
  the 
  vertical 
  anterior 
  median 
  symphysis, 
  and 
  in 
  

   later 
  editions 
  of 
  this 
  work 
  a 
  sketch 
  was 
  inserted 
  illustrating 
  this 
  

   structure. 
  The 
  writer 
  also 
  had 
  the 
  opportunity 
  some 
  eleven 
  years 
  

   ago, 
  while 
  visiting 
  the 
  Hugh 
  Miller 
  collection 
  in 
  the 
  Edinburgh 
  

   Museum 
  of 
  Science 
  and 
  Art, 
  of 
  examining 
  and 
  making 
  a 
  draw- 
  

   ing 
  of 
  a 
  mandible 
  labeled 
  Coccosteus, 
  in 
  which 
  the 
  symphysial 
  

   teeth 
  are 
  distinctly 
  exhibited. 
  I 
  presume 
  this 
  is 
  that 
  figured 
  by 
  

   H. 
  Miller. 
  Claypole 
  has 
  also 
  shown 
  their 
  existence 
  in 
  his 
  

   species 
  C. 
  Cuyahogce.\ 
  

  

  In 
  the 
  Livonia 
  specimens 
  there 
  is 
  no 
  evidence 
  of 
  this 
  structure 
  

   which 
  appears 
  to 
  be 
  normal 
  to 
  Coccosteus. 
  The 
  three 
  stout 
  

   terminal 
  teeth 
  are 
  large 
  and 
  distinctly 
  above 
  the 
  symphysis, 
  as 
  is 
  

   very 
  clearly 
  shown 
  in 
  man. 
  2. 
  

  

  The 
  resemblance 
  to 
  Dinicthys 
  is 
  in 
  the 
  form 
  of 
  the 
  ramus 
  and 
  

   the 
  presence 
  of 
  the 
  row 
  of 
  conical 
  denticles, 
  to 
  D. 
  Herzeri 
  and 
  

   D. 
  intermedius, 
  Newberry, 
  rather 
  than 
  to 
  D. 
  Terrelli, 
  Newberry 
  

   and 
  D. 
  Newberryi, 
  Clarke, 
  in 
  which 
  there 
  are 
  no 
  denticles, 
  but 
  a 
  

   long 
  cutting 
  edge. 
  

  

  ♦Palaeozoic 
  Fishes 
  of 
  North 
  America, 
  p. 
  143. 
  t 
  American 
  Geologist, 
  March, 
  1893, 
  p. 
  169. 
  

  

  