﻿On 
  a 
  Variety 
  0/ 
  Porcelllo 
  scaber, 
  Latr. 
  71 
  

  

  IX. 
  — 
  On 
  an 
  interefitinq 
  Variety 
  0/ 
  Porcellio 
  scaber, 
  Latr. 
  

   i^Y 
  Walter 
  E. 
  Collinge," 
  M.Sc, 
  F.L.S., 
  F.E.IS. 
  

  

  Well-marked 
  variations 
  among-st 
  the 
  British 
  Terrestrial 
  

   Isopoda, 
  apart 
  from 
  colour-variations, 
  are 
  by 
  no 
  means 
  

   common. 
  To 
  some 
  extent 
  this 
  is 
  probably 
  due 
  to 
  the 
  fact 
  

   that 
  the 
  different 
  species 
  have 
  not 
  received 
  the 
  same 
  attention 
  

   as 
  have 
  those 
  of 
  other 
  groups. 
  

  

  I 
  have 
  recently 
  received 
  from 
  Mr. 
  P. 
  A. 
  Aubin, 
  of 
  

   St. 
  Helier, 
  Jersey, 
  Channel 
  Isle^, 
  who 
  has 
  given 
  me 
  most 
  

   valuable 
  assistance 
  in 
  my 
  studies 
  of 
  the 
  Channel 
  Island 
  

   species, 
  a 
  very 
  interesting 
  variation, 
  which 
  I 
  think 
  is 
  worthy 
  

   of 
  recording;. 
  

  

  PorcelUo 
  scaher^ 
  Latr., 
  var. 
  aubini, 
  nov. 
  

  

  Colour 
  a 
  creamy 
  white, 
  with 
  a 
  few 
  small 
  sepia 
  or 
  slaty- 
  

   coloured 
  dashes. 
  First 
  segment 
  of 
  the 
  mesosome 
  strongly 
  

   convex, 
  giving 
  the 
  bead 
  a 
  somewhat 
  tucked-in 
  appearance, 
  

   Tiie 
  backward 
  curve 
  of 
  the 
  lateral 
  plates 
  less 
  acute. 
  Tubercles 
  

   fewer, 
  less 
  prominent, 
  and 
  more 
  irregular 
  in 
  arrangement. 
  

   Distinct 
  transverse 
  ridge 
  on 
  the 
  tergum 
  of 
  the 
  last 
  thoracic 
  

   segment. 
  Lateral 
  lobes 
  of 
  cephalon 
  smaller 
  and 
  of 
  a 
  different 
  

   contour 
  to 
  type 
  ; 
  frontal 
  lobe 
  less 
  prominent. 
  Basal 
  joint 
  of 
  

   antennse 
  smaller. 
  Uropoda 
  : 
  exopodite 
  more 
  contracted 
  proxi- 
  

   mally, 
  giving 
  the 
  appendage 
  a 
  more 
  conical 
  shape. 
  

  

  Hub. 
  From 
  wet 
  moss 
  growing 
  on 
  face 
  of 
  a 
  road 
  cutting 
  

   through 
  shale; 
  St. 
  Helier, 
  Jersey, 
  Channel 
  Isles. 
  

  

  I 
  have 
  pleasure 
  in 
  associating 
  with 
  this 
  interesting 
  variety 
  

   the 
  name 
  of 
  Mr. 
  Aubin. 
  

  

  I 
  may 
  mention 
  that 
  I 
  have 
  taken 
  a 
  very 
  similar 
  colour- 
  

   variety, 
  icithout 
  ike 
  above 
  structural 
  differences^ 
  in 
  Cheshire, 
  

   Warwickshire, 
  Worcestershire, 
  and 
  Staffordshire 
  ; 
  but, 
  

   holding 
  the 
  view 
  that 
  colour-variations, 
  especially 
  in 
  the 
  

   Isopoda, 
  are 
  of 
  very 
  little 
  importance 
  unless 
  associated 
  with 
  

   structural 
  differences, 
  I 
  have 
  not 
  previously 
  recorded 
  them. 
  

  

  