Am,  Jour.  Pharm. ") 
Ai:g.,  1885.  j 
Gleanings  in  Materia  Medica. 
403 
lected  in  a  tared  platinum  or  porcelain  dish.  Evaporate  the  alcohol 
on  the  water-bath  and  dry  in  the  air-bath  above  100°C.  to  constant 
weight.  After  noting  this,  heat  the  glycerin,  and  burn  it.  The  weight 
of  the  ash  is  deducted  from  the  total  weight ;  the  difPerenc  is  glycerin. 
The  percentage  of  ash  compared  with  the  total  percentage  of  glycerin 
is  by  itself  an  important  factor,  as  glycerin  derived  by  this  mode  of 
treatment  from  pure  butter  gives  5  per  cent,  of  ash,  whereas  the  gly- 
cerin of  oleomargarine  and  other  similar  fats  leaves  only  from  0*3  to 
0*6  per  cent. 
By  this  method  I  have  found,  after  deduction  of  said  ash,  3*75  per 
cent,  glycerin  in  pure  butter ;  7  per  cent,  glycerin  in  oleomargarine. — 
Jour.  Amer.  Chem.  Soc,  May,  1885,  p.  135. 
GLEANINGS  IN  MATERIA  MEDICA. 
By  the  Editor. 
Trehala  which  is  used  as  food  in  Syria,  has  been  investigated  by 
Guibourt  (1858),  Berthelot  and  Han  bury.  It  is  a  cocoon  formed 
upon  a  species  of  Echinops  by  a  beetle  which  has  been  named  Larinus 
niditicans,  Guibourt,  L.  subrugosus,  Chevrolat,  and  L.  maculatus, 
Falderniann.  The  same  substance  has  now  been  further  examined  by 
Dr.  G.  Apping  (Thesis,  Dorpat,  1885).  His  chemical  analysis  yielded 
moisture  10*78,  ash  2*79,  fat  and  chlorophyll  O'lG,  trehalose  23*84, 
tannin  and  citric  acid  traces;  albuminoids  soluble  in  water  8*09, 
soluble  in  soda  1*88,  and  insoluble  in  both  liquids  2*31  ;  cellulose  like 
substance  derived  from  starch  24*90  ;  true  starch  6*72  ;  mucilage  soluble 
in  water  7*60,  and  mucilage  insoluble  in  water  10*93.  The  most  import- 
ant constituents,  trehalose,  starch  and  mucilage,  were  fully  examined,  and 
inquiries  were  made  into  the  origin  of  trehala.  The  cocoon  is  a  product 
of  the  larva,  but  the  material  for  this  structure,  although  of  vegetable 
origin,  cannot  have  been  derived  from  the  plant,  upon  which  it  was  built, 
since  Apping  found  the  pith  and  other  portions  of  the  tissue  of  the 
stems  to  be  entirely  free  from  starch  and  from  trehalose,  while  the 
granules  detected  iii  portions  gnawed  by  the  larva  were  observed  to  be 
outside  of  the  cell  walls;  these  microscopic  observations  were  verified 
by  Professor  Russow. 
Maize  and  oil  of  maize.  Maize  or  Indian  corn  is  a  valuable  article 
of  food,  containing  about  10  per  cent,  of  nitrogenous  principles  and  7 
per  cent.,  or  in  some  varieties  9*5  per  cent,  of  fat.    The  presence  of 
