﻿OLD 
  AND 
  NEW 
  WORLD 
  MELANIANS 
  — 
  ^MORRISON 
  381 
  

  

  Genus 
  Sulcospira 
  Troschel, 
  1857 
  

  

  Genotype: 
  (Melania 
  sulcospira 
  Mousson=) 
  Sulcospira 
  sulcospira 
  

   (Mousson). 
  

  

  Recorded 
  as 
  "also 
  viviparous," 
  this 
  group 
  must 
  be 
  studied 
  further 
  

   before 
  its 
  true 
  relationships 
  to 
  the 
  other 
  genera 
  from 
  the 
  Malayan 
  

   region 
  can 
  be 
  proved. 
  Troschel 
  (1857, 
  p. 
  114) 
  has 
  recorded 
  the 
  

   radular 
  characters; 
  the 
  shell 
  appears 
  similar 
  to 
  certain 
  species 
  of 
  

   Brotia, 
  to 
  Tylomelania, 
  or 
  to 
  immature 
  individuals 
  of 
  Balanocochlis. 
  

   Until 
  the 
  animal 
  characters 
  are 
  reexamined, 
  Sulcospira 
  may 
  be 
  left 
  

   tentatively 
  in 
  the 
  "Melanoides 
  complex." 
  

  

  Genus 
  Balanocochlis 
  Fischer, 
  1885 
  

  

  Genotype: 
  (Melania 
  glans 
  von 
  dem 
  Busch=) 
  Balanocochlis 
  glans 
  

   (von 
  dem 
  Busch) 
  1842. 
  

  

  Philippine 
  animals 
  of 
  this 
  species, 
  collected 
  by 
  R. 
  T. 
  Abbott 
  at 
  San 
  

   Ramon, 
  Mindanao 
  (USNM 
  543951), 
  have 
  recently 
  been 
  examined. 
  

   These 
  animals 
  prove 
  the 
  genus 
  to 
  be 
  thiarid. 
  There 
  is 
  a 
  minute 
  

   brood-pouch 
  pore 
  bordered 
  with 
  "flaps," 
  similar 
  to 
  that 
  figured 
  for 
  

   Melanoides 
  turriculus 
  (pi. 
  11, 
  fig. 
  14), 
  low 
  on 
  the 
  right 
  side 
  and 
  close 
  

   to 
  the 
  fringed 
  mantle 
  edge. 
  Apparently 
  there 
  are 
  many 
  hundreds 
  of 
  

   minute 
  eggs 
  in 
  the 
  brood 
  pouch. 
  Either 
  they 
  develop 
  as 
  numerous, 
  

   small, 
  equal-sized 
  young 
  shells 
  as 
  in 
  certain 
  Melanoides 
  species, 
  or 
  

   they 
  may 
  be 
  released 
  in 
  the 
  veliger 
  stage 
  for 
  a 
  free-swimming 
  larval 
  

   period, 
  as 
  is 
  known 
  for 
  the 
  genus 
  Stenomelania. 
  The 
  material 
  ex- 
  

   amined, 
  which 
  contained 
  only 
  the 
  eggs, 
  is 
  not 
  conclusive 
  on 
  this 
  point. 
  

   In 
  any 
  case, 
  the 
  shell 
  and 
  opercular 
  characters 
  are 
  distinct 
  enough 
  

   from 
  any 
  other 
  thiarids 
  known 
  to 
  maintain 
  the 
  full 
  generic 
  separation 
  

   of 
  Balanocochlis. 
  The 
  earlier 
  name 
  Melania 
  inermis 
  Lesson 
  1830 
  was 
  

   preoccupied 
  by 
  Gray 
  in 
  1825; 
  the 
  later 
  name 
  M. 
  siccata 
  von 
  dem 
  

   Busch 
  1843 
  probably 
  represents 
  young 
  of 
  the 
  species 
  Balanocochlis 
  

   glans. 
  

  

  Genus 
  Tylomelania 
  P. 
  and 
  F. 
  Sarasin, 
  1898 
  

  

  Genotype: 
  Tylomelania 
  neritiformis 
  P. 
  and 
  F. 
  Sarasin. 
  

  

  This 
  subpaludomiform 
  group 
  of 
  shells 
  only 
  appears 
  as 
  a 
  separate 
  

   development 
  of 
  shell 
  outline 
  and 
  proportions 
  ; 
  they 
  have 
  the 
  same 
  type 
  

   of 
  "paleomelanian" 
  operculum 
  and 
  the 
  same 
  general 
  radular 
  char- 
  

   acters 
  as 
  do 
  Antimelania 
  and 
  Brotia. 
  The 
  animals 
  of 
  all 
  the 
  groups 
  

   must 
  be 
  completely 
  and 
  carefully 
  reexamined 
  before 
  the 
  genera 
  (and 
  

   the 
  distinctions 
  of 
  the 
  genera) 
  of 
  the 
  "Melanoides 
  complex" 
  of 
  the 
  

   Thiaridae 
  can 
  be 
  properly 
  organized 
  or 
  understood. 
  Shell, 
  radular, 
  

   and 
  opercular 
  characters 
  of 
  this 
  group 
  were 
  carefully 
  recorded 
  by 
  the 
  

   Sarasins 
  (1898, 
  p. 
  52, 
  pi. 
  4, 
  figs. 
  56, 
  57; 
  pi. 
  8, 
  figs. 
  110, 
  111; 
  pi. 
  9, 
  fig. 
  

   115), 
  but 
  they 
  did 
  not 
  examine 
  the 
  details 
  of 
  the 
  reproduction 
  of 
  

   Tylomelania. 
  

  

  