﻿131 
  

  

  circumstances 
  as 
  well 
  as 
  the 
  ease 
  with 
  which 
  they 
  are 
  collected, 
  

   when 
  considered 
  in 
  connection 
  with 
  the 
  sparseness 
  of 
  individ- 
  

   uals, 
  rendered 
  it 
  almost 
  certain 
  that 
  they 
  would 
  be 
  subject 
  to 
  

   the 
  attacks 
  of 
  parasites. 
  It 
  was 
  also 
  certain 
  that 
  these 
  para- 
  

   sites 
  when 
  discovered 
  would 
  be 
  of 
  small 
  size 
  and 
  that 
  a 
  mod- 
  

   erate 
  sized 
  Ichneumonid 
  or 
  Braconid 
  was 
  not 
  to 
  be 
  looked 
  for, 
  

   since 
  none 
  such 
  (other 
  than 
  can 
  be 
  otherwise 
  accounted 
  for) 
  

   are 
  to 
  be 
  found 
  in 
  the 
  haunts 
  of 
  Rhyncogo7ius 
  throughout 
  the 
  

   islands. 
  Through 
  Mr. 
  Giffard's 
  perseverance, 
  we 
  are 
  now 
  able 
  

   to 
  say 
  that 
  one 
  check, 
  and 
  no 
  doubt 
  a 
  very 
  important 
  one, 
  to 
  the 
  

   multiplication 
  of 
  Rhyncogonus 
  hlackhwmi 
  is 
  an 
  egg-parasite 
  of 
  

   the 
  genus 
  Eupehnus, 
  the 
  species 
  being 
  previously 
  undescribed. 
  

   From 
  the 
  specimens 
  of 
  egg-masses 
  of 
  the 
  beetle 
  submitted 
  to 
  

   me 
  by 
  Mr. 
  Giffard, 
  from 
  which 
  two 
  of 
  the 
  parasites 
  had 
  

   emerged, 
  I 
  suspect 
  that 
  one 
  egg 
  affords 
  sufficient 
  food 
  for 
  one 
  

   parasite, 
  though 
  the 
  latter 
  is 
  of 
  large 
  size 
  for 
  the 
  amount 
  of 
  

   nutriment 
  that 
  it 
  would 
  thence 
  obtain. 
  When 
  I 
  exposed 
  these 
  

   egg 
  masses 
  by 
  separating 
  the 
  koa 
  leaves, 
  which 
  were 
  very 
  firmly 
  

   glued 
  together 
  and 
  concealed 
  them, 
  in 
  both 
  cases 
  I 
  found 
  the 
  

   remaining 
  eggs, 
  together 
  with 
  some 
  dead 
  larvae 
  of 
  the 
  beetle, 
  

   to 
  be 
  covered 
  with 
  a 
  mass 
  of 
  minute 
  Acari, 
  which 
  had 
  partially 
  

   devoured 
  them, 
  as 
  also 
  several 
  still 
  immature 
  pupae 
  of 
  the 
  

   Eupelmus. 
  The 
  attacks 
  of 
  Acarids 
  are 
  frequently 
  a 
  cause 
  of 
  

   great 
  trouble 
  in 
  rearing 
  insects 
  in 
  captivity 
  in 
  these 
  islands, 
  

   but 
  seem 
  to 
  be 
  of 
  conparatively 
  small 
  account 
  under 
  natural 
  

   conditions. 
  The 
  two 
  parasites, 
  that 
  had 
  emerged 
  from 
  one 
  of 
  

   the 
  egg-masses 
  had 
  escaped 
  by 
  the 
  same 
  round 
  hole 
  gnawed 
  

   through 
  the 
  Acacia 
  leaf. 
  The 
  other 
  eggs-mass 
  had 
  also 
  been 
  

   parasitized, 
  but 
  the 
  contents 
  all 
  destroyed 
  by 
  the 
  Acarids. 
  

   Probably 
  the 
  Eupelmus, 
  like 
  some 
  other 
  egg-parasites, 
  will 
  only 
  

   attack 
  the 
  eggs 
  when 
  comparatively 
  freshly 
  laid, 
  and 
  the 
  ex- 
  

   tremely 
  wet 
  weather 
  would 
  sufficiently 
  account 
  for 
  the 
  fact 
  

   that 
  not 
  more 
  of 
  the 
  egg-masses, 
  exposed 
  to 
  parasitic 
  attack 
  by 
  

   Mr. 
  Giffard, 
  were 
  parasitized. 
  I^o 
  doubt, 
  in 
  many 
  of 
  the 
  

   eggs 
  experimented 
  with, 
  embryonic 
  development 
  had 
  already 
  

   advanced 
  too 
  far 
  before 
  their 
  exposure 
  to 
  parasites. 
  It 
  is 
  note- 
  

   worthy 
  that 
  the 
  one 
  egg-mass 
  found 
  under 
  natural 
  conditions 
  

   yielded 
  parasites 
  only. 
  

  

  The 
  Hawaiian 
  species 
  of 
  Eupelmus 
  are 
  numerous, 
  and 
  the 
  

   parasite 
  of 
  Rhyncogonus 
  is 
  one 
  of 
  the 
  smallest 
  of 
  these. 
  The 
  

   genus 
  as 
  represented 
  in 
  the 
  islands 
  is 
  very 
  remarkable 
  for 
  the 
  

   diversity 
  in 
  habits 
  of 
  the 
  different 
  species. 
  One 
  is 
  known 
  to 
  

   be 
  parasitic 
  on 
  Coleopterous 
  larvae 
  (xinobiidae), 
  one 
  has 
  been 
  

  

  