﻿68 
  Boyer: 
  Rare 
  species 
  of 
  

  

  Glyphodesmis 
  tumida 
  sp. 
  nov. 
  

  

  Valves 
  linear, 
  tumid 
  in 
  the 
  middle, 
  with 
  subcuneate 
  ends. 
  

   Central 
  and 
  terminal 
  nodules 
  distinct. 
  Pseudoraphe 
  distinct, 
  

   widened 
  in 
  the 
  middle. 
  Striae 
  slightly 
  radiating 
  at 
  the 
  ends, 
  

   moniliform, 
  nine 
  in 
  lo 
  ju. 
  Length 
  of 
  valve 
  95 
  ju. 
  [Fig. 
  2.] 
  

  

  : 
  Campeche 
  Bay, 
  Mexico 
  

   marine 
  : 
  known 
  from 
  the 
  1 
  

  

  Resemble 
  

  

  ; 
  Dimero 
  gramma 
  marinum 
  (Greg.) 
  Ralfs 
  in 
  outline 
  

   but 
  differs 
  in 
  possessing 
  a 
  central 
  nodule 
  and 
  finer 
  strlation. 
  It 
  

   differs 
  from 
  Glyphodesmis 
  Williamsonii 
  (Greg.) 
  Gnin. 
  in 
  outline 
  

  

  ■ 
  L 
  

  

  and 
  somewhat 
  resembles 
  Plagiogramma 
  Loczyi 
  Pant., 
  considered 
  

   by 
  Brun 
  a 
  form 
  of 
  G. 
  Williamsonii. 
  

  

  Glyphodesmis 
  campechiana 
  sp. 
  nov. 
  

  

  Valves 
  llnear-lanceolate, 
  tumid 
  In 
  the 
  middle 
  and 
  tapering 
  to 
  

   the 
  subacute 
  ends. 
  Central 
  pseudonodule 
  distinct 
  ; 
  terminal 
  

   spaces 
  ovate. 
  Striae 
  marginal, 
  twelve 
  in 
  10 
  ju, 
  leaving 
  a 
  broad, 
  

   lanceolate, 
  hyaline 
  area 
  about 
  half 
  the 
  width 
  of 
  the 
  valve. 
  Length 
  

   of 
  valve 
  30 
  ju. 
  [Fig. 
  10.] 
  

  

  Type 
  locality: 
  Campeche 
  Bay, 
  Mexico. 
  

  

  Distribution: 
  marine: 
  known 
  from 
  the 
  tvnp 
  TnrAHtv 
  nnlv. 
  

  

  Synedra 
  anguinea 
  sp. 
  nov. 
  

  

  gmold 
  

  

  'gmoid 
  at 
  the 
  ends. 
  Valves 
  linear, 
  

  

  narrow, 
  somewhat 
  indefinite. 
  Striae 
  nine 
  or 
  ten 
  in 
  10 
  /i, 
  radiate 
  

   at 
  the 
  ends, 
  punctate, 
  Interrupted 
  by 
  a 
  marginal 
  line 
  on 
  each 
  side. 
  

   Length 
  of 
  valve 
  315 
  /x. 
  [Fig. 
  i.] 
  

  

  : 
  Colon, 
  Panama, 
  

   marine: 
  known 
  from 
  

  

  Rare. 
  

  

  mcisa 
  

  

  F 
  

  

  I 
  

  

  Valves 
  linear-lanceolate, 
  with 
  subcapitate 
  ends. 
  One 
  or 
  both 
  

   sides 
  more 
  or 
  less 
  deeply 
  incised. 
  Pseudoraphe 
  scarcely 
  evident. 
  

   Striae 
  about 
  eighteen 
  in 
  lo 
  ju. 
  Length 
  of 
  valve 
  25-50 
  n. 
  [FiG. 
  8.] 
  

  

  LOCALITY 
  

  

  Distribution: 
  fresh 
  water; 
  known 
  from 
  the 
  type 
  locality 
  only, 
  

   where 
  it 
  is 
  abundant. 
  

  

  Closely 
  resembles 
  Synedra 
  affinis 
  Baileyana 
  H. 
  H. 
  Chase 
  

   (in 
  Walker 
  & 
  Chase, 
  Some 
  New 
  and 
  Rare 
  Diatoms 
  4. 
  pi 
  2, 
  f. 
  i) 
  

  

  