﻿196 
  I'UOCUKDINOS 
  OK 
  TIIK 
  M 
  ALACOI.OOICAI- 
  SOCIETY. 
  

  

  Genus 
  PLEUEOTOMELLA. 
  VcrriU, 
  1873. 
  

   Usually 
  considered 
  to 
  bo 
  a 
  section 
  of 
  Daphnella, 
  but 
  I 
  think 
  it 
  may 
  

   be 
  raised 
  to 
  {>:eneric 
  rank. 
  Tiie 
  species 
  possess 
  a 
  common 
  " 
  facies" 
  

   wlierever 
  they 
  arc 
  found. 
  The 
  sliell 
  is 
  as 
  a 
  rule 
  more 
  or 
  less 
  turreted 
  

   or 
  gradate. 
  ' 
  

  

  175. 
  rr.KUR0T0MKr,LA 
  ALCESTIS 
  (]\[elv.). 
  

  

  Laphiella 
  {Pleurotomella) 
  alcestis, 
  Melvill, 
  Proc. 
  Malac. 
  Soc. 
  Loud., 
  

   vol. 
  vii, 
  1906, 
  p. 
  78, 
  pi. 
  viii, 
  f. 
  23. 
  

  

  r.G. 
  Gulf 
  of 
  Ouian, 
  hit. 
  24° 
  58' 
  N., 
  long. 
  56° 
  54' 
  E., 
  156 
  fathoms. 
  

  

  Allied 
  to 
  PL 
  amphthlestrum, 
  Melv., 
  and 
  culinicnes, 
  Melv., 
  but 
  more 
  

   fusiform 
  in 
  contour, 
  with 
  regular 
  quadrate 
  decussating 
  sculpture, 
  

   mouth 
  oblong, 
  canal 
  sliglilly 
  produced. 
  Colour 
  pure 
  Avhite. 
  

  

  176. 
  rLHUUOTOMIOr.L.l 
  AMlMIIIiLKSTRUM 
  (Melv.j. 
  

  

  Clathirella 
  nmphihledrmn, 
  ^Melvill, 
  Proc. 
  Malac. 
  Soc. 
  Lond., 
  vol. 
  vi, 
  

   1904, 
  p. 
  18, 
  pi. 
  V, 
  f. 
  7. 
  

  

  P.G. 
  Gulf 
  of 
  Ouum, 
  hit. 
  24° 
  58' 
  N., 
  long. 
  56° 
  54' 
  E., 
  156 
  fathoms. 
  

  

  It 
  is 
  often 
  difficult 
  to 
  draw 
  a 
  hard 
  and 
  Hrst 
  line 
  between 
  the 
  

   Clathurinoc 
  and 
  certain 
  outlying 
  Daphnelloid 
  species, 
  and 
  tliis 
  is 
  a 
  case 
  

   in 
  point. 
  iV. 
  amphiblestnim 
  is 
  a 
  somewhat 
  coarsely 
  cancellate 
  species, 
  

   the 
  nuclear 
  whorls 
  ochreous, 
  very 
  finely 
  and 
  beautifully 
  decussate. 
  

   The 
  anal 
  sinus 
  is 
  very 
  distinct, 
  coming 
  just 
  below 
  the 
  suture. 
  

   It 
  seems 
  comparable 
  with 
  Daphnella 
  hrazieri, 
  Angas,' 
  an 
  Australian 
  

   species, 
  well 
  figured 
  by 
  Hedley,' 
  but 
  this 
  species 
  is 
  inclined 
  to 
  be 
  

   slightly 
  shouldered 
  at 
  the 
  upper 
  part 
  of 
  the 
  whorls. 
  

  

  177. 
  Pleuuoxomklla 
  AMrnrnuTKs 
  (M. 
  & 
  St.). 
  

   Diiphnclla 
  {Pleurotomella) 
  amphitn'ies, 
  Melvill 
  & 
  Standen, 
  Ann. 
  Mag. 
  

  

  Nut. 
  Hist., 
  ser. 
  vir, 
  vol. 
  xii, 
  1903, 
  p. 
  316, 
  pi. 
  xxiii, 
  f, 
  3. 
  

  

  P.G. 
  Gulf 
  of 
  Oman, 
  hit. 
  24° 
  58' 
  N., 
  long. 
  56° 
  54' 
  E., 
  156 
  fathoms. 
  

  

  Found 
  with 
  PL 
  nerehium 
  (M. 
  & 
  St.), 
  which 
  differs 
  from 
  it 
  in 
  

   greater 
  angularity 
  of 
  whorl 
  and 
  less 
  obesity 
  of 
  contour. 
  Both 
  are 
  

   pure 
  white, 
  delicately 
  chased 
  shells, 
  of 
  considerable 
  beauty. 
  

  

  178. 
  Plkuuotomki.la 
  kcpiioua 
  (Melv.). 
  

   Mangilia 
  ecphom, 
  ^Eelvill, 
  Proc. 
  Malac. 
  Soc. 
  Lond., 
  vol. 
  vi, 
  1904, 
  

   p. 
  58, 
  pi. 
  v, 
  f. 
  5. 
  

   P.G. 
  Gulf 
  of 
  Oman, 
  lat. 
  21° 
  58' 
  N., 
  long. 
  56° 
  54' 
  E., 
  156 
  fathoms. 
  

   The 
  projecting 
  spiral 
  ridge 
  encircling 
  the 
  body 
  -whorl 
  amply 
  

   characterizes 
  this 
  peculiar 
  little 
  species. 
  The 
  nuclear 
  whorls 
  are 
  

   beautifully 
  caucellate 
  ; 
  sinus 
  but 
  lightly 
  expressed. 
  

  

  179. 
  Plkurotomklla. 
  edlimenes 
  (Melv.). 
  

   Daphnella 
  eulmenes, 
  Melvill, 
  Journ. 
  of 
  Mulac, 
  vol. 
  xi, 
  1904, 
  p. 
  84, 
  

   pi. 
  viii, 
  f. 
  15. 
  

   P.G. 
  Gulf 
  of 
  Oman, 
  lat. 
  24° 
  08' 
  N., 
  long. 
  56° 
  54' 
  E.; 
  156 
  fatlioms. 
  

   A 
  graceful 
  species, 
  of 
  rare 
  occurrence 
  at 
  tlie 
  above 
  veiy 
  prolific 
  

  

  ' 
  Proc. 
  Zool. 
  Soc. 
  Lond., 
  1871, 
  p. 
  18, 
  pi. 
  i, 
  f. 
  22. 
  

   2 
  Mem. 
  Austral. 
  Mus., 
  iv, 
  pt. 
  6, 
  190:5, 
  p. 
  392, 
  f. 
  107. 
  

  

  