﻿On 
  a 
  new 
  Species 
  of 
  Polytoreutus. 
  507 
  

  

  LIX. 
  — 
  Description 
  of 
  a 
  new 
  Species 
  of 
  the 
  Genus 
  Polytoreutus. 
  

   By 
  Dr. 
  Luigi 
  Cognetti 
  de 
  Mabtiis, 
  R. 
  MuseoZoologico, 
  

   Lormo. 
  

  

  Peof. 
  F. 
  J. 
  Bell, 
  of 
  the 
  British 
  Museum, 
  has 
  recently 
  sent 
  

   me 
  an 
  East-African 
  earthworm 
  which 
  I 
  have 
  been 
  able 
  to 
  

   recognize 
  as 
  the 
  type 
  of 
  a 
  new 
  species. 
  I 
  wish 
  to 
  express 
  

   my 
  thanks 
  to 
  him 
  for 
  his 
  kindness 
  in 
  sending 
  me 
  many 
  earth- 
  

   worms 
  which 
  from 
  time 
  to 
  time 
  have 
  come 
  into 
  his 
  hands 
  

   for 
  identification. 
  

  

  Polytoreutus 
  baralypton 
  *. 
  

  

  External 
  characters. 
  — 
  Length 
  225 
  mm., 
  thickness 
  4-5 
  mm. 
  ; 
  

   number 
  of 
  segments 
  310. 
  

  

  Colour 
  white 
  yellowish. 
  

  

  Ventral 
  setae 
  much 
  wider 
  apart 
  than 
  the 
  external 
  setse. 
  At 
  

   the 
  x. 
  segment 
  aa=-2\ 
  ah, 
  ab 
  = 
  \bc, 
  ad 
  equal 
  to 
  half 
  of 
  

   the 
  whole 
  circumference. 
  At 
  the 
  middle 
  region 
  of 
  the 
  body 
  

   aa 
  = 
  2 
  ab 
  = 
  bc, 
  ad 
  always 
  = 
  i 
  circumference. 
  Nephridial 
  

   pores 
  in 
  the 
  lines 
  of 
  the 
  lateral 
  bundles 
  of 
  setse. 
  

  

  Clitellum 
  developed 
  all 
  round 
  the 
  body 
  and 
  occupying 
  

   segments 
  xiii. 
  to 
  xviii. 
  

  

  A 
  single 
  male 
  pore 
  on 
  intersegmental 
  furrow 
  xvii.-xviii., 
  

   in 
  the 
  middle 
  ventral 
  line 
  ; 
  a 
  small 
  depressed 
  oval 
  area 
  

   surrounds 
  this 
  pore. 
  

  

  Female 
  pores 
  are 
  not 
  recognizable. 
  They 
  lie 
  in 
  the 
  inter- 
  

   segmental 
  furrow 
  xiv.-xv., 
  and 
  are, 
  ventrally, 
  near 
  to 
  the 
  

   lines 
  of 
  nephridial 
  pores. 
  

  

  A 
  single 
  spermathecal 
  pore 
  behind 
  the 
  male 
  pore 
  upon 
  

   intersegmental 
  furrow 
  xviii.-xix. 
  It 
  is 
  surrounded 
  by 
  a 
  

   whitish 
  ring. 
  

  

  Internal 
  anatomy. 
  — 
  Septa 
  v.-vi. 
  to 
  xi.-xii. 
  a 
  little 
  thick- 
  

   ened. 
  

  

  A 
  strong 
  gizzard 
  lies 
  in 
  the 
  v. 
  segment. 
  

  

  Unpaired 
  oesophageal 
  glands 
  or 
  ventral 
  pouches 
  (" 
  Chylus- 
  

   taschen 
  ") 
  in 
  segments 
  ix., 
  x., 
  and 
  xi. 
  ; 
  a 
  pair 
  of 
  calci- 
  

   ferous 
  glands 
  in 
  the 
  xiii. 
  segment, 
  developed 
  around 
  the 
  

   oesophagus, 
  but 
  interrupted 
  in 
  the 
  dorsal 
  and 
  ventral 
  middle 
  

   lines. 
  

  

  Dorsal 
  vessel 
  single 
  ; 
  large 
  hearts 
  in 
  the 
  x. 
  and 
  xi. 
  segments. 
  

  

  A 
  pair 
  of 
  testes 
  (?free) 
  depends 
  in 
  the 
  xi. 
  segment 
  from 
  

  

  * 
  Philosophical 
  term. 
  

  

  