ON  SANTONATE  PROTOXIDE  OF  MERCURY. 
159 
mind  the  appearance  of  the  crystalline  lens  with  its  concentric 
layers  and  radiating  fibres. 
The  ovary  vesicated.  The  result  also  was  obtained  from  the 
isolated  eggs,  crushed  and  mingled  with  cerate.  A  large  pyri- 
form  sac  attached  to  the  generative  apparatus  of  the  female, 
contains  a  yellow  sebaceous-like  matter,  together  with  a  mass 
of  hard  opaque  white  substance.  The  former  material  appears 
to  consist  of  spermatic  matter,  epithelial  cells,  and  an  albumin- 
ous substance  ;  and  it  is  inert  as  a  vesicant.  The  mass  of  hard 
white  substance  is  composed  of  the  same  fat-like  spherules  above 
described  as  existing  in  accessory  glands  of  the  male  generative 
apparatus.  I  have  occasionally  observed  it  to  be  absent,  and 
suspect  that  together  with  the  other  contents  of  the  pyriform 
sac  it  is  derived  from  the  male.  Mingled  with  cerate,  I  found 
it  also  to  be  a  vesicant.  My  friend,  Dr.  Darrach,  also  applied 
portions  of  the  two  different  substances,  from  the  pyriform  sac 
of  the  female  generative  apparatus,  to  his  forearm.  The  fatty- 
like spherules  alone  vesicated. 
Thus,  as  a  result  of  the  experiments  above  briefly  detailed, 
the  vesicating  principle  of  Lytta  vittata  appears  to  belong  to 
the  blood,  the  peculiar  fatty  substance  of  certain  accessory 
glands  of  the  generative  apparatus,  and  to  the  eggs. — Am. 
Journ.  Med.  jSci.  Jan.  1860. 
ON  SANTONATE  OF  PROTOXIDE  OF  MERCURY,  AN  EXCELLENT 
VERMIFUGE. 
The  solutions  of  equal  parts  of  protonitrate  of  mercury  and 
santonate  of  soda,  in  distilled  water,  are  mixed ;  after  24  hours, 
the  precipitate  is  separated  by  a  filter,  well  washed  with  distilled 
water,  dried  at  a  moderate  heat,  and  preserved  in  bottles  ex- 
cluded from  the  light. 
The  protosantonate  of  mercury  is  a  whitish  powder,  some- 
what crystalline  under  a  magnifier,  inodorous,  and  of  a  slight 
metallic  taste,  which  is  afterwards  bitterish  and  very  persistent. 
It  is  insoluble  in  water  and  alcohol,  unaltered  at  212°,  charred 
at  a  high  temperature  and  decomposed  into  mercury  and  red 
oxide  of  mercury;  lime  water  decomposes  it  into  soluble  santon- 
ate of  lime  and  black  oxide  of  mercury. 
