﻿ACADEMY 
  OE 
  SCIENCES. 
  371 
  

  

  and 
  black 
  poiuts 
  as 
  in 
  twelve. 
  Stigmata 
  white, 
  edged 
  anteriorly 
  with 
  black. 
  

   Below 
  the 
  stigmata, 
  and 
  parallel 
  with 
  them, 
  is 
  a 
  row 
  of 
  very 
  minute 
  black 
  dots, 
  

   edged 
  with 
  greenish-white. 
  Feet, 
  yellowish-green, 
  with 
  the 
  tips 
  purplish-black. 
  

   Abdominal 
  legs, 
  greenish-yellow, 
  with 
  the 
  edges 
  purplish-black. 
  Viewed 
  from 
  

   behind, 
  the 
  anal 
  segment 
  is 
  yellowish-green. 
  

  

  Length, 
  3.30 
  inch. 
  

  

  Width, 
  ^nter. 
  0.60 
  inch 
  ; 
  post. 
  0.40 
  inch. 
  

  

  Food 
  plants, 
  Ceonotliis 
  ihyrsiflorus, 
  Esch. 
  ;• 
  Frangula 
  Californica, 
  Gray 
  ; 
  

   Rhamnus 
  croceus, 
  Nutt; 
  Alnui 
  viridis, 
  D. 
  0. 
  

  

  When 
  about 
  to 
  undergo 
  its 
  change, 
  the 
  caterpillar 
  attaches 
  itself 
  usually 
  to 
  

   the 
  under 
  side 
  of 
  a 
  twig, 
  and 
  spins 
  a 
  rather 
  coarse 
  and 
  very 
  compact 
  outer 
  case, 
  

   with 
  which 
  no 
  leaves 
  or 
  other 
  extraneous 
  substances 
  are 
  incorporated, 
  and 
  with- 
  

   in 
  this 
  a 
  reddish-brown 
  cocoon, 
  the 
  filaments 
  of 
  which 
  are 
  strong, 
  rather 
  coarse, 
  

   but 
  glossy. 
  The 
  cocoon 
  and 
  its 
  outer 
  case 
  are 
  oval, 
  produced 
  into 
  a 
  cone 
  at 
  the 
  

   end, 
  by 
  which 
  the 
  insect 
  escapes. 
  

  

  Chrysalis. 
  Pitchy, 
  almost 
  black, 
  very 
  short, 
  rounded 
  in 
  front, 
  and 
  much 
  

   swollen 
  about 
  the 
  abdominal 
  region. 
  Segments 
  rough, 
  and 
  transversely 
  

   wrinkled. 
  

  

  Length, 
  1.15 
  inch. 
  

  

  The 
  caterpillar 
  changes 
  to 
  a 
  chrysalis 
  in 
  September, 
  and 
  the 
  imago 
  appears 
  

   in 
  the 
  following 
  May 
  or 
  June. 
  This 
  beautiful 
  insect 
  was 
  once 
  remarkably 
  com- 
  

   mon 
  around 
  the 
  Bay 
  of 
  San 
  Francisco, 
  but 
  the 
  march 
  of 
  improvement 
  has 
  de- 
  

   stroyed 
  most 
  of 
  its 
  haunts, 
  and 
  it 
  must 
  now 
  be 
  regarded 
  as 
  one 
  of 
  our 
  really 
  

   rare 
  species. 
  

  

  Gastropacha. 
  sp. 
  

  

  In 
  August, 
  1873, 
  I 
  found, 
  in 
  Vancouver 
  Island, 
  a 
  cocoon 
  which 
  I 
  did 
  not 
  

   recognize, 
  and 
  was 
  surprised 
  at 
  finding 
  that 
  it 
  produced, 
  in 
  April 
  last, 
  a 
  beauti- 
  

   ful 
  insect 
  of 
  this 
  genus. 
  Mr. 
  Stretch 
  believes 
  the 
  species 
  to 
  be 
  identical 
  with 
  

   the 
  European 
  G. 
  betulifoUa 
  ; 
  but 
  as 
  I 
  am 
  not 
  familiar 
  with 
  the 
  transformations 
  

   of 
  that 
  species, 
  I 
  append 
  the 
  following 
  : 
  

  

  • 
  Chrijmlis. 
  Black, 
  covered 
  with 
  a 
  dense 
  woolly 
  substance, 
  powdered 
  with 
  a 
  

   fine 
  dust, 
  and 
  enclosed 
  in 
  a 
  very 
  soft, 
  woolly 
  cocoon, 
  formed, 
  apparently, 
  of 
  very 
  

   fine 
  silk, 
  with 
  which 
  a 
  few 
  yellowish-brown 
  hairs 
  are 
  intermingled. 
  The 
  cocoon 
  

   is 
  placed 
  in 
  the 
  angle 
  of 
  a 
  frond 
  of 
  Pteris, 
  the 
  frondlets 
  being 
  drawn 
  together 
  

   at 
  the 
  edges 
  as 
  a 
  covering. 
  

  

  Larva. 
  Some 
  days 
  after 
  the 
  finding 
  of 
  the 
  above-mentioned 
  chrysalis, 
  I 
  dis- 
  

   covered 
  a 
  larva 
  at 
  the 
  base 
  of 
  an 
  oak 
  tree, 
  which 
  spun 
  a 
  cocoon 
  precisely 
  similar 
  

   to 
  that 
  previously 
  described, 
  and 
  I 
  therefore 
  believe 
  it 
  to 
  be 
  the 
  same 
  species 
  ; 
  

   but 
  as 
  the 
  perfect 
  insect 
  has 
  not 
  yet 
  made 
  its 
  appearance, 
  I 
  give 
  a 
  description 
  of 
  

   the 
  caterpillar, 
  without 
  further 
  reference 
  to 
  its 
  identity 
  : 
  

  

  Black, 
  very 
  minutely 
  spotted 
  with 
  white, 
  each 
  segment 
  with 
  a 
  broad, 
  white, 
  

   transverse 
  band, 
  slightly 
  triangular 
  dorsally, 
  with 
  the 
  apex 
  of 
  the 
  angle 
  directed 
  

   anteriorly. 
  The 
  four 
  anterior 
  segments 
  have 
  a 
  number 
  of 
  chestnut-colored 
  

  

  Proc. 
  Cal. 
  Acad. 
  Sci., 
  Vol. 
  V.~24. 
  December, 
  1874. 
  

  

  