As?ptJe0mUberPhitoom-}       Investigation  of  the  Tannins,  431 
Lloyd,  of  Forest  Grove,  Ore.,  sent  a  sample  of  the  bark  of  Q. 
garryana.  A  sample  of  the  bark  of  Q.  macrocarpa  was  collected 
near  Springfield,  O.,  by  W.  E.  Ridenour,  and  a  sample  of  the 
bark  of  Q.  virens  was  obtained  through  Dr.  Mohr,  of  Alabama.  The 
following  results  were  obtained  : 
Species. 
Moisture. 
Ash  in 
Absolutely- 
Dry  Bark. 
Tannin  in 
Absolutely 
Dry  Bark. 
Q. 
777 
20-65 
5-88 
Q. 
8-97 
I9'i7 
8'39 
Q. 
icrio. 
8'53 
13*65 
Q- 
garryana  
4-91 
11-65 
6-i6 
Q. 
9-96 
6-58 
3'55 
The  tannins  of  all  of  the  barks  gave  qualitative  reactions  like 
those  of  the  members  of  the  oak  bark  group  already  reported  by 
Professor  Trimble.  The  tannin  of  Quercus  garryana  showed  5966 
per  cent,  of  carbon,  and  5-55  per  cent,  of  hydrogen,  establishing 
its  relationship  to  the  members  of  the  oak  bark  group  of  tannins. 
The  ash  of  Q.  garryana  consisted  almost  exclusively  of  calcium 
phosphate. 
Acorns  of  Quercus  Reticulata. — A  sample  of  the  acorns  of  this 
species  of  oak  was  supplied  by  Professor  Tourney,  of  the  Agricultural 
Experiment  Station  at  Tucson,  Ariz.  The  pericarp  was  removed 
from  the  kernel,  and  each  part  estimated  separately  with  the  fol- 
lowing results  : 
Pericarp.  Kernels. 
Moisture  5-81  6'8o 
Ash  in  absolutely  dry  2  60  4*04 
Tannin  in  absolutely  dry  .  .  ,  3*08  4*20 
The  ash  of  both  parts  contained  aluminum,  calcium,  magnesium, 
potassium,  iron  and  manganese,  combined  with  phosphoric,  hydro- 
chloric and  sulphuric  acids;  that  of  the  pericarp  contained  silicic 
acid  in  addition  to  the  foregoing. 
