Aug' 1885''^™'}         Gleanings  in  Materia  Medica.  405 
Tannin  gave  a  turbidity  only  with  barbaloin,  probably  due  to  a 
decomposition  product. 
For  the  detection  of  aloin  the  feces  were  digested  with  water  acidu- 
lated with  sulphuric  acid,  then  macerated  for  12  hours  with  three 
volumes  of  strong  alcohol,  the  filtrate  concentrated,  and  the  residue 
successively  agitated  with  petroleum  benzin  and  amylic  alcohol ;  on 
evaporating  the  latter  aloin  was  left.  The  treatment  of  blood  and 
urine  was  similar.  From  his  results  the  author  concludes  that  on 
taking  aloes  or  aloin,  the  greater  portion  is  excreted  with  the  faeces ;  a 
small  portion  only  is  absorbed  and  passes  mostly  through  the  kidneys 
while  the  remainder  enters  the  liver  and  with  the  bile  is  conveyed  back 
into  the  intestines. 
Froduets  of  Xanthorrhcea.  Baron  Ferd.  von  Mueller  (Zeitschr. 
Oesterr.  Apoth.  Yer.  1885,  293)  gives  an  account  of  the  geographical 
distribution  in  Australia  and  Tasmania  of  the  different  species  of  this 
genus  and  of  their  resinous  products,  which  of  late  years  have  been 
extensively  exported  by  Messrs.  William  Somerville  and  Henry  Wilks 
who  prefer  the  resin  of  X.  hastilis,  X.  quadrangulata  and  X.  Tateana 
for  various  reasons ;  X.  Preissii  yields  one  of  the  best  resins,  and  is 
widely  distributed  in  Western  Australia.  The  resin  of  X.  hastilis  is 
known  as  gum  acroides,  is  yellow  and  lighter  colored  than  the  other  kinds, 
usually  more  sticky,  and  less  inclined  to  become  pulverulent ;  it  is  rather 
fragrant,  but  less  so  than  the  resin  of  X.  quadrangulata.  A  comestible 
gum  somewhat  resembling  tragacanth  is  sometimes  deposited  in  the 
trunk  in  vertical  concentric  layers.  300  tons  of  the  resins  of  X.  hastilis 
have  been  exported  in  one  year,  and  at  one  time  the  price  rose  to  £65 
per  ton  for  the  best  quality,  but  for  ordinary  quality  is  from  £7-10. 
One  trunk  yields  on  an  average  5  pounds  of  resin  which  exudes  from 
the  persistent  rudiments  of  the  leaf  bases,  the  exudation  being  some- 
times increased  by  bush  fires. 
The  resin  of  X.  Tateana  is  dark  reddish-brown,  like  the  resin  of 
X.  australis,  but  dryer ;  a  trunk  yields  about  20  pounds,  and  during 
the  collection  of  the  resin  is  destroyed  ;  the  value  is  about  £25  per  ton. 
The  author  has  sometimes  seen  masses  of  resin  weighing  50  pounds 
at  the  base  of  the  trunk  of  X.  australis,  most  probably  the  produce  of 
several  years  melted  together  by  repeated  fires.  X.  semiplana  is  stem- 
less  and  produces  little  resin.  X.  minor  is  matted,  the  tufts  of  leaves 
being  approximate  and  radical.  In  wet  soil  X.  Preissii  remains 
stemless. 
