Am.  Jour.  Pharm.  \ 
May,  1901.  J 
Animal  Parasites  in  Man. 
231 
Given  a  specimen  collected  in  this  manner,  add  to  it  a  quantity  of 
water,  stir  gently  with  a  glass  rod,  after  which  it  will  be  seen 
that  the  worm  falls  to  the  bottom  of  the  vessel,  when  decant 
one-half,  or  more,  of  the  liquid,  which  is  replaced  by  clean  water. 
This  washing  is  repeated  until  the  worm  is  cleansed.  The  worm, 
with  the  water  surrounding  it,  is  now  transferred  to  a  clear  glass 
dish  10  x  12x3  inches,  which  is  placed  on  a  white  surface  (towel) 
and  all  large  segments  are  removed  by  a  glass  rod,  drawing  them 
over  the  edge  of  the  dish,  when  they  are  allowed  to  fall  into  a  sec- 
ond dish  containing  water;  care  being  taken  not  to  break  the 
parasite. 
After  all  large  segments  are  removed,  the  head  is  usually  readily 
detected,  by  the  naked  eye,  floating  amongst  the  remaining  thread- 
like portions  of  the  parasite.  In  searching  for  certain  small  para- 
sites a  hand-glass  may  be  found  of  service.  The  head  is  transferred 
to  50  per  cent,  glycerine  and  preserved  for  further  study.  In  mount- 
ing parasite  heads,  a  slide  provided  with  a  concavity  of  sufficient 
depth  to  accommodate  their  thickest  portion,  is  most  satisfactory. 
They  are  well  preserved  when  mounted  in  Farrant's  medium,  cast 
medium,  glycerine  and  glycerine  jelly  {Fig.  2). 
lcenia  Echinococcus  (Dog  Tape  Worm). — Here  the  problem  is 
somewhat  different,  as  man  is  the  intermediary  host,  and  in  him 
develops  the  head,  or  scolex  of  the  parasite  only.  Each  head  is 
provided  with  a  crown  of  hooklets,  and  many  free  hooks  are  often 
seen  in  connection  with  shreds  of  finely  granular,  yellowish  mem. 
brane  (Fig.  j).  Hooklets,  scolices  and  membrane  from  the  cysts  of 
the  echinococcus  are  occasionally  found  in  sputum,  pus  from 
abscesses,  the  fluid  of  cysts,  feces  and  urine.  Hooklets  are 
best  studied  under  a  y§  lens,  while  the  heads  may  be  detected 
under  a  much  lower  power.  It  is  these  findings  which  enables  one 
to  recognize  the  parasite,  and  the  hooks  may  be  the  only  evidence 
present.  In  the  study  of  this  parasite  a  low  power  of  illumination 
is  necessary,  and  the  skilful  manipulation  of  both  Abbe  condenser 
and  iris  diaphragm  afford  great  assistance.  Products  of  the  echino- 
coccus may  be  mounted  in  any  of  the  above  mounting  mediums. 
Trichina  Spiralis. — The  larvae  of  this  parasite  appear  in  the  mus- 
cular tissue  of  man  after  the  ingestion  of  uncooked,  infected  pork. 
They  make  their  appearance  early  in  the  diaphragm,  frontal,  and 
muscles  of  the  leg.    The  material  to  be  studied  is  collected  by  the 
