THE  CICADA  SEPTENDECIM. 
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of  air,  or  carbonic  acid,  is  passed  over  the  liquid  in  the  still ;  the 
distillation  is  continued  until  the  distillate  ceases  to  give  with 
solution  of  caustic  potash  a  darkish  coloration.  To  the  distillate 
twice  its  bulk  of  water  is  added,  while  in  order  to  decompose  the 
acetic  ether,  finely  powdered  hydrate  of  baryta  is  added,  with 
continuous  agitation  of  the  liquid  until  a  decided  alkaline  reac- 
tion sets  in  ;  the  excess  of  baryta  is  removed  by  carbonic  acid. 
The  aldehyd  is  afterwards  separated  from  the  liquid  by  careful 
distillation  on  a  water  bath,  and  purified  by  combining  it  with 
ammonia.  If  the  impure  madder  spirit  is  agitated  with  sodium 
amalgam,  perfectly  pure  alcohol  is  obtained ;  since  the  aldehyd 
is  by  this  means  hydrogenized  to  alcohol,  and  the  acetic  ether  is 
decomposed  into  alcohol,  while  acetate  of  soda  is  formed.  — Lond. 
Chem.  News,  June  26,  1868. 
THE  CICADA  SEPTENDECIM. 
During  this  month,  (August,)  the  Seventeen-year  Locust,  [Ci- 
cada septendecim  of  Linnseus)  has  disappeared,  and  only  a  few 
Harvest-flies,  as  the  two  other  species  we  have  are  called,  raise 
their  shrill  cry  during  the  dog-days.  But  as  this  year  has  been 
marked  by  the  appearance  of  vast  swarms  in  the  Middle  States, 
we  cannot  do  better  than  give  a  brief  summary  of  its  history, 
which  we  condense  from  Dr.  Harris'  work. 
The  Seventeen-year  Locust  ranges  from  South-eastern  and 
Western  Massachusetts  to  Louisiana.  Of  its  distribution  west 
of  the  Mississippi  Valley  we  have  no  accurate  knowledge.  In 
Southern  Massachusetts  they  appear  in  oak  forests  about  the 
middle  of  June.  After  pairing,  the  female,  by  means  of  her 
powerful  ovipositor,  bores  a  hole  obliquely  to  the  pith,  and  lays 
therein  from  ten  to  twenty  slender  white  eggs,  which  are  arranged 
in  pairs,  somewhat  like  the  grains  on  an  ear  of  wheat,  and  im- 
planted in  the  limb.  She  thus  oviposits  several  times  in  a  twig, 
and  passes  from  one  to  another,  until  she  has  laid  four  or  five 
hundred  eggs.  After,  this  she  soon  dies.  The  eggs  hatch  in 
about  two  weeks,  though  some  observers  state  that  they  do  not 
hatch  for  from  forty  to  over  fifty  days  after  being  laid.  The 
active  grubs  are  provided  with  three  pairs  of  legs.    After  leaving 
