﻿572 
  

  

  and 
  October 
  being 
  the 
  worst. 
  Reproduction 
  appears 
  to 
  be 
  almost 
  

   exclusively 
  parthenogenetic, 
  as 
  males 
  only 
  occur 
  very 
  rarely. 
  In 
  

   order 
  to 
  ascertain 
  the 
  number 
  of 
  larvae 
  carried 
  by 
  the 
  wind 
  in 
  

   a 
  given 
  time, 
  over 
  a 
  given 
  distance, 
  glass 
  slabs 
  covered 
  with 
  bird- 
  

   lime 
  were 
  used. 
  Beeches 
  are 
  infested 
  at 
  all 
  periods 
  of 
  their 
  

   existence, 
  and 
  the 
  universal 
  occurrence 
  of 
  the 
  pest 
  makes 
  the 
  

   treatment 
  of 
  single 
  trees 
  useless. 
  Experiments, 
  still 
  in 
  progress, 
  

   show 
  that 
  a 
  female 
  lays 
  at 
  least 
  15 
  eggs, 
  which 
  should 
  give 
  rise 
  to 
  

   50,625 
  females 
  in 
  4 
  years. 
  In 
  spite 
  of 
  this 
  only 
  a 
  shght 
  increase 
  is 
  

   usually 
  visible 
  after 
  6 
  years, 
  and 
  investigation 
  shows 
  that 
  this 
  is 
  due 
  

   to 
  the 
  fact 
  that 
  they 
  seldom 
  survive 
  when 
  the 
  host 
  tree 
  is 
  in 
  normal 
  

   health. 
  The 
  scales 
  avoid 
  very 
  soft, 
  tender 
  and 
  ''corky" 
  bark, 
  and 
  

   also 
  trees 
  which 
  Limax 
  arhorum 
  has 
  cleared 
  of 
  their 
  covering 
  of 
  hchen 
  

   and 
  Protococcus 
  pluvialis. 
  Scrubbing 
  is 
  therefore 
  a 
  measure 
  of 
  some 
  

   value. 
  An 
  outbreak 
  is 
  only 
  an 
  increase 
  of 
  existing 
  scale 
  infesta- 
  

   tion 
  due 
  to 
  the 
  trees 
  suffering 
  injury 
  from 
  other 
  causes, 
  as 
  

   shown 
  by 
  the 
  fact 
  that 
  a 
  healthy 
  tree 
  will 
  remain 
  uninfested, 
  though 
  

   growing 
  close 
  to 
  a 
  severely 
  infested 
  one. 
  The 
  observations 
  of 
  many 
  

   years 
  prove 
  that 
  the 
  trees 
  are 
  not 
  killed 
  by 
  scale 
  infestation 
  alone, 
  and 
  

   on 
  trees 
  which 
  have 
  died 
  subsequently 
  to 
  such 
  infestation 
  brown 
  or 
  

   brown-black 
  spots 
  occur 
  on 
  the 
  trunks, 
  which 
  exude 
  a 
  fluid. 
  These 
  

   are 
  probably 
  not 
  caused 
  by 
  Cryptococcus 
  fagi, 
  and 
  the 
  author 
  thinks 
  

   that 
  they 
  are 
  due 
  to 
  a 
  hitherto 
  unknown 
  fungus. 
  Leptis 
  and 
  other 
  

   flies 
  suck 
  the 
  fluid 
  from 
  these 
  spots 
  and 
  possibly 
  act 
  as 
  carriers. 
  The 
  

   death 
  of 
  the 
  trees 
  is 
  hastened 
  by 
  various 
  pests, 
  first 
  Xylotecus 
  

   domesticus, 
  then 
  Lymexylon 
  dermestoides. 
  Nectria 
  ditissima 
  and 
  other 
  

   fungi 
  follow. 
  The 
  author 
  considers 
  the 
  chief 
  enemies 
  concerned 
  in 
  

   the 
  destruction 
  of 
  the 
  beech 
  to 
  be 
  the 
  agent 
  causing 
  the 
  spots 
  and 
  

   Nectria 
  ditissima. 
  Neither 
  of 
  these 
  is 
  at 
  present 
  controllable, 
  but 
  

   Cryptococcus 
  fagi, 
  which 
  undoubtedly 
  injures 
  the 
  tree, 
  should 
  not 
  be 
  

   neglected. 
  When 
  attacks 
  of 
  the 
  three 
  pests 
  occur 
  in 
  less 
  than 
  10 
  per 
  

   cent, 
  of 
  the 
  trees 
  the 
  axe 
  is 
  perhaps 
  the 
  best 
  remedy. 
  In 
  more 
  severe 
  

   infestations 
  the 
  scales 
  may 
  be 
  energetically 
  brushed 
  off 
  the 
  bark, 
  

   and 
  if 
  over 
  20 
  per 
  cent, 
  of 
  the 
  trees 
  are 
  attacked 
  they 
  should 
  be 
  

   sprayed 
  with 
  Schacht's 
  Fruit-tree 
  Carbolineum, 
  1 
  part 
  in 
  4 
  parts 
  of 
  

   water, 
  or 
  painted 
  with 
  a 
  solution 
  made 
  up 
  of 
  1 
  part 
  and 
  5 
  parts 
  

   water, 
  at 
  an 
  estimated 
  cost 
  of 
  about 
  225. 
  per 
  acre. 
  

  

  Mote 
  (D. 
  C). 
  The 
  Cheese 
  Skipper 
  (Piophila 
  casei, 
  L.). 
  — 
  Ohio 
  Nat, 
  

   Columbus, 
  xiv, 
  no. 
  7, 
  May 
  1914, 
  pp. 
  309-316, 
  1 
  pi. 
  

  

  The 
  cheese 
  skipper 
  (Piophila 
  casei, 
  L.), 
  so 
  called 
  on 
  account 
  of 
  the 
  

   pecuhar 
  leaping 
  habits 
  of 
  the 
  larva, 
  is 
  of 
  considerable 
  economic 
  

   importance 
  to 
  man 
  on 
  account 
  of 
  its 
  attacks 
  on 
  cheese, 
  smoked 
  meats, 
  

   etc., 
  and 
  its 
  possible 
  relation 
  to 
  mjnasis. 
  The 
  fly 
  deposits 
  its 
  eggs 
  

   upon 
  bacon, 
  cheeses, 
  smoked 
  ham, 
  slightly 
  putrid 
  meat, 
  etc. 
  The 
  

   duration 
  of 
  the 
  egg 
  stage 
  is 
  23-54 
  hours, 
  and 
  of 
  the 
  larval 
  period 
  

   14 
  days. 
  Pupation 
  occurs 
  in 
  drier 
  places 
  than 
  those 
  in 
  which 
  the 
  

   larvae 
  feed 
  and 
  occupies 
  12 
  days. 
  The 
  flies, 
  in 
  an 
  experiment, 
  seemed 
  

   to 
  prefer 
  beef-steak 
  with 
  a 
  slightly 
  putrid 
  odour 
  for 
  purposes 
  of 
  ovi- 
  

   position. 
  The 
  adult 
  flies 
  lived 
  longer 
  and 
  the 
  larvae 
  fed 
  and 
  matured 
  

   more 
  readily 
  on 
  this 
  than 
  on 
  other 
  foods. 
  The 
  anatomy 
  of 
  the 
  larva 
  

   and 
  adult 
  fly 
  is 
  described. 
  

  

  