Am.  Jour.  Pharm.  ) 
December,  1910.  | 
Insects  Destructive  to  Books. 
559 
subject  to  attacks  of  species  of  Thysanura  and  Collembola,  which  are 
naturally  attracted  by  heat ;  and,  as  heat  rises,  the  books  on  the  top 
shelves  will  be  found  to  be  the  ones  damaged  by  these  insects.  They 
are  seldom  found  where  it  is  damp. 
The  spring-tails,  Lcpidocyrtus  americanus,  and  the  silver-fish, 
Lepisma  saccharina,  come  under  this  group. 
Gases;  Poisonous,  etc.,  Combined. — The  tree,  from  which  is 
made  the  wood  pulp  used  in  the  manufacture  of  paper,  has  its  roots 
shooting  down  into  the  bowels  of  the  earth,  and  its  branches  and 
leaves  reaching  up  into  the  heavens.  The  roots  are  fed  by  a 
varied  combination  of  elements,  mineral,  gaseous,  and  vegetable, 
and  these  elements,  taken  in  by  the  roots,  are  by  a  wonderful  system 
of  arteries  carried  into  every  portion  of  the  tree,  and  insects  are 
thus  able  to  get  all  elements  that  are  necessary  for.  them  to  sustain 
life.  The  pores  of  the  skin  are  the  health  holes  of  the  body,  and  in 
a  sore,  unless  it  is  sterilized,  life  is  bound  to  start,  and  that  first  life 
again  is  worm  life,  no  matter  how  carefully  the  wound  is  protected 
on  the  outside.  If  a  microscope  was  used,  the  body  would  be  found 
to  be  covered  with  animated  matter.  The  insects,  preying  upon  ani- 
mal life,  are  after  the  poisons  exuded  by  the  blood  and  skin. 
Omnivorous. — Among  the  insects  which  can  find  food  in  all 
portions  of  the  books  may  be  mentioned  the  beetles,  Sitodrepa  pani- 
cea  and  Tribolium  confusum. 
Carnivorous. — The  following  are  some  of  the  forms  of  life 
found  preying  upon  insects  found  in  libraries,  the  centipede,  Scu- 
tigera  forceps,  pseudoscorpions,  Bryobia  prcctensis  and  Tryoglyphus 
longior.  I  believe  that  investigation  will  show  that  the  two  last 
species  are  injurious  to  books. 
Researches. — Some  of  the  statements  here  made  seem  radical, 
but  when  it  is  considered  how  little  is  known  of  the  life  habits  of  the 
lower  forms  of  life.,  on  the  one  hand,  and  the  facts  given  by  the 
few  life  histories  that  are  known,  on  the  other,  it  does  not  appear 
to  me  unreasonable  to  place  this  theory  before  the  public.  Especially 
so,  as  my  own  experiments  are  showing  results  entirely  different 
from  anything  hitherto  published. 
It  is  known  that  the  eggs  of  the  insects  under  adverse  conditions 
will  stay  fertile  for  long  periods  of  time ;  that  the  eggs  will  also 
stand  a  very  high  or  low  temperature ;  and,  on  account  of  the  tough- 
ness of  their  skin  or  shell,  are  also  able  to  stand  a  great  deal  of 
handling  and  pressure  without  being  crushed  or  broken.    At  an 
