﻿458 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  io3 
  

  

  Genus 
  Echininus 
  Clench 
  and 
  Abbott, 
  1942 
  

  

  Echininus, 
  sensu 
  stricto, 
  is 
  limited 
  to 
  the 
  Indo-Pacific. 
  It 
  differs 
  

   from 
  the 
  subgenus 
  Tectininus 
  Clench 
  and 
  Abbott 
  in 
  having 
  an 
  um- 
  

   bilicus 
  and 
  in 
  having 
  a 
  more 
  spinulose 
  sculpturing. 
  It 
  was 
  formerly 
  

   known 
  as 
  Nina 
  Gray, 
  1850 
  (non 
  Horsfield 
  1829, 
  non 
  Nina 
  Gray 
  1855). 
  

   Echinella 
  of 
  Kesteven, 
  1903, 
  and 
  some 
  other 
  authors 
  is 
  this 
  genus, 
  

   but 
  Echinella 
  Swainson 
  is 
  a 
  synonym 
  of 
  Tectarius 
  Valenciennes. 
  

   Genotype, 
  by 
  original 
  designation, 
  is 
  Trochus 
  cumingi 
  Philippi. 
  

  

  Subgenus 
  Tectininus 
  Clench 
  and 
  Abbott, 
  1942 
  

  

  Many 
  of 
  the 
  subgeneric 
  characters 
  listed 
  here 
  may 
  well 
  be 
  those 
  

   of 
  the 
  genus 
  as 
  a 
  whole, 
  but 
  we 
  have 
  not 
  had 
  an 
  opportunity, 
  as 
  yet, 
  

   to 
  examine 
  the 
  genotype 
  of 
  Echininus, 
  sensu 
  stricto, 
  in 
  detail. 
  The 
  

   genotype, 
  by 
  original 
  designation, 
  is 
  Echininus 
  nodulosus 
  Pfeiffer. 
  

  

  The 
  general 
  anatomy, 
  both 
  internal 
  and 
  external, 
  is 
  typically 
  lit- 
  

   torinid. 
  Operculum 
  loosely 
  multispiral 
  with 
  about 
  6 
  whorls 
  (trochid 
  

   opercula 
  of 
  the 
  same 
  diameter, 
  such 
  as 
  in 
  Calliostoma 
  and 
  Margarites, 
  

   have 
  11 
  to 
  13 
  whorls). 
  Shell 
  whorls 
  roughly 
  bicarinate, 
  with 
  the 
  

   upper 
  carina 
  bearing 
  about 
  one-third 
  fewer 
  nodules 
  than 
  the 
  lower 
  

   carina. 
  Columella 
  short, 
  and 
  not 
  shelved 
  or 
  protruding 
  downward 
  

   beyond 
  the 
  base 
  of 
  the 
  outer 
  lip 
  as 
  in 
  Nodilittorina. 
  Radula 
  ribbon 
  

   with 
  about 
  800 
  to 
  1,250 
  transverse 
  rows 
  of 
  teeth. 
  Unused 
  ribbon 
  

   coiled 
  in 
  about 
  16 
  close 
  turns 
  and 
  located 
  in 
  the 
  dorsal 
  region 
  behind 
  

   the 
  head. 
  Central 
  tooth 
  extremely 
  small 
  and 
  slender. 
  Lateral 
  teeth 
  

   very 
  large, 
  strong, 
  and 
  with 
  a 
  strong, 
  hooked, 
  single 
  cusp. 
  Inner 
  

   marginal 
  tooth 
  with 
  a 
  single, 
  large 
  cusp. 
  Outer 
  marginal 
  tooth 
  half 
  

   the 
  length 
  of 
  the 
  lateral 
  one, 
  and 
  tri-denticulate. 
  Foot 
  weakly 
  di- 
  

   taxic, 
  with 
  retrograde 
  waves. 
  Penis 
  large 
  and 
  located 
  on 
  the 
  right 
  

   side 
  of 
  the 
  head 
  just 
  below 
  and 
  slightly 
  posterior 
  to 
  the 
  base 
  of 
  the 
  

   right 
  tentacle. 
  Penis 
  tri-lobed 
  and 
  with 
  a 
  seminal 
  groove 
  running 
  

   along 
  the 
  posterior 
  edge. 
  In 
  the 
  area 
  where 
  the 
  accessory 
  prong 
  arises 
  

   there 
  are 
  numerous, 
  small 
  papillae 
  on 
  the 
  penis. 
  In 
  the 
  female, 
  the 
  

   ovaries 
  are 
  widespread 
  through 
  the 
  digestive 
  gland 
  and 
  are 
  grass- 
  

   green 
  in 
  color. 
  The 
  area 
  of 
  the 
  prostate 
  gland 
  in 
  the 
  males 
  is 
  bright 
  

   Prussian 
  blue. 
  

  

  Echininus 
  nodulosus 
  Pfeiflfer 
  

  

  Turbo 
  tuberculatus 
  Wood 
  (iion 
  Pennant, 
  1777), 
  Index 
  testaceologicus, 
  suppl., 
  

   p. 
  19, 
  pi. 
  6, 
  fig. 
  30, 
  1828. 
  

  

  Litorina 
  nodulosa 
  Pfeiffer, 
  Arch. 
  Naturg., 
  vol. 
  1, 
  p. 
  367 
  (exclusive 
  of 
  synonymy), 
  

   1839. 
  (Cuba.) 
  

  

  Litorina 
  scabra 
  Anton, 
  Verzeichniss 
  der 
  Conchylien 
  . 
  . 
  . 
  , 
  p. 
  53, 
  1839. 
  

  

  Litorina 
  antoni 
  Philippi 
  (new 
  name 
  for 
  Littorina 
  scabra 
  Anton, 
  non 
  L. 
  scabra 
  

   Linn6, 
  1758, 
  of 
  authors), 
  Abbildungen 
  und 
  Beschreibungen 
  . 
  . 
  . 
  Con- 
  

   chylien 
  . 
  . 
  . 
  , 
  vol. 
  2, 
  p. 
  145, 
  pi. 
  2, 
  fig. 
  18, 
  1847. 
  

  

  