﻿232 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  as 
  do 
  their 
  larvae, 
  commonly 
  known 
  as 
  '' 
  skippers," 
  from 
  their 
  habit 
  of 
  

   bringing 
  the 
  two 
  ends 
  of 
  the 
  body 
  together 
  and 
  by 
  sudden 
  straightening 
  

   with 
  a 
  quick 
  muscular 
  action 
  throwing 
  themselves 
  to 
  a 
  distance 
  of 
  four 
  

   or 
  five 
  inches 
  or 
  more. 
  The 
  larva 
  or 
  skipper 
  'Ms 
  cylindrical, 
  tapering 
  

   gradually 
  toward 
  the 
  anterior 
  end, 
  truncate 
  posteriorly, 
  and 
  furnished 
  at 
  

   this 
  extremity 
  with 
  two 
  horny 
  projecting 
  stigmata 
  and 
  a 
  pair 
  of 
  fleshy 
  

   filaments 
  (see 
  a 
  in 
  the 
  figure). 
  The 
  egg 
  is 
  pearly 
  white, 
  slender 
  oblong, 
  

   slightly 
  curved, 
  i 
  mm. 
  m 
  length, 
  with 
  a 
  diameter 
  of 
  about 
  one-fourth 
  the 
  

   length 
  " 
  (Murtfeldt). 
  

  

  Life-History. 
  

  

  For 
  our 
  knowledge 
  of 
  the 
  life-history 
  of 
  the 
  insect, 
  we 
  are 
  mainly 
  

   indebted 
  to 
  the 
  careful 
  observations 
  of 
  Miss 
  Murtfeldt. 
  

  

  The 
  eggs 
  are 
  deposited 
  in 
  more 
  or 
  less 
  compact 
  clusters 
  of 
  five 
  to 
  

   fifteen 
  in 
  the 
  cracks 
  and 
  checks 
  of 
  cheese, 
  upon 
  the 
  surface 
  of 
  cured 
  or 
  

   partially 
  cured 
  meats, 
  and, 
  in 
  the 
  case 
  of 
  canvassed 
  meats, 
  on 
  the 
  cover- 
  

   ing 
  or 
  in 
  its 
  folds; 
  sometimes 
  they 
  are 
  scattered 
  singly. 
  The 
  number 
  of 
  

   eggs 
  deposited 
  averaged 
  about 
  thirty 
  in 
  the 
  breeding 
  cage^s, 
  though 
  the 
  

   conditions 
  were 
  not 
  normal 
  and 
  the 
  number 
  may 
  have 
  been 
  diminished 
  

   in 
  consequence. 
  A 
  popular 
  article 
  in 
  Harpefs 
  New 
  Monthly 
  Magazine 
  

   {loc. 
  cit.) 
  credits 
  this 
  insect 
  with 
  depositing 
  nearly 
  three 
  hundred 
  eggs, 
  

   which 
  is 
  probably 
  a 
  gross 
  over-estimate. 
  

  

  The 
  eggs 
  hatch 
  within 
  thirty-six 
  hours, 
  and 
  the 
  tiny 
  white 
  maggots 
  attack 
  

   at 
  once 
  their 
  food 
  — 
  in 
  meat, 
  the 
  fatty 
  portions. 
  They 
  complete 
  their 
  

   growth 
  in 
  seven 
  to 
  eight 
  days 
  and 
  are 
  then 
  seven 
  to 
  nine 
  millimeters 
  

   (about 
  one-third 
  of 
  an 
  inch) 
  in 
  length. 
  The 
  transformation 
  from 
  the 
  

   fuU-grownlarva 
  to 
  the 
  perfect 
  fly 
  occupies 
  ten 
  days. 
  In 
  the 
  breeding 
  

   cage, 
  adult 
  flies 
  on 
  an 
  average 
  did 
  not 
  live 
  longer 
  than 
  a 
  week. 
  They 
  

   would 
  sip 
  a 
  little 
  at 
  sweets 
  but 
  were 
  not 
  greatly 
  attracted 
  to 
  them, 
  while 
  

   the 
  odor 
  of 
  smoked 
  meats 
  speedily 
  drew 
  them. 
  The 
  flies 
  were 
  not 
  

   active 
  at 
  night, 
  although 
  they 
  could 
  perform 
  their 
  functions 
  in 
  partially 
  

   darkened 
  places. 
  No 
  definite 
  succession 
  of 
  generations 
  could 
  be 
  noted, 
  

   but 
  the 
  insect 
  in 
  all 
  stages 
  was 
  present 
  from 
  May 
  until 
  into 
  October 
  or 
  

   November. 
  Severe 
  and 
  protracted 
  cold 
  proved 
  fatal 
  to 
  the 
  insect 
  in 
  all 
  

   its 
  stages. 
  The 
  above 
  is 
  the 
  result 
  of 
  Miss 
  Murtfeldt's 
  observations 
  on 
  

   the 
  insect 
  in 
  the 
  month 
  of 
  August 
  and 
  later. 
  

  

  In 
  February 
  of 
  the 
  same 
  year. 
  Prof. 
  Kellogg, 
  then 
  of 
  the 
  Kansas 
  State 
  

   University, 
  studied 
  the 
  development 
  of 
  this 
  insect. 
  According 
  to 
  his 
  

   observations, 
  the 
  egg 
  stage 
  lasted 
  four 
  days; 
  the 
  larvae 
  required 
  two 
  

   weeks 
  to 
  complete 
  their 
  growth, 
  and 
  they 
  remained 
  in 
  the 
  pupa 
  state 
  one 
  

   week. 
  Dr. 
  H. 
  F. 
  Kessler, 
  as 
  quoted 
  by 
  Dr. 
  Howard, 
  has 
  carefully 
  studied 
  

   the 
  life-history 
  of 
  this 
  fly 
  in 
  Europe. 
  He 
  found 
  that 
  the 
  average 
  time 
  

  

  