276 BOTANICAL GAZETTE [octoper 
and have been treated with copper acetate, reddish-brown, amor- 
phous, or somewhat crystalline masses are found adhering to the walls 
of the cells. These masses when amorphous are made up entirely of 
tannin and when somewhat crystalline contain an admixture of tannin 
and gallic acid. 
III. When the winged insect has developed, (1) only a few layers 
of the cells of the central zone remain, and these contain a number of 
tannin vacuoles. Surrounding the latter are several (as many as 12) 
rows of prominent lignified cells. (2) The cells of the middle layer 
in specimens which are of this age and have been treated with coppét 
acetate, contain numerous brownish-red tannin masses to which may 
be adhering some yellowish-brown crystals of gallic acid. But the 
tannin is in by far the greatest quantity in the cells of this layer and 
at this age of the galls. (3) The cells of the external layer also contain 
tannin masses. 
Conclusion.—(a) It is well known that gallic acid occurs naturally in 
the nut galls (the product of Cynips gallae tinctoriae Olivier on Quercus 
Lusitanica Lamck.) ; the leaves of Arctostaphylos Uva-urst (L.) Spreng. 
Thea Chinensis Sims, and of various species of Riws; the fruit of Laiaas 
nalia chebula Retzius(Myrobalans), and Caesalpinia coriaria Willd. (Divi- 
Divi); the acorn cups of Quercus A¢gilops L. (Valonia); and may be 
obtained by extraction with water in the form of silky needles and 
asymmetric prisms. With the alkalies, alkaline earths, lead and 
copper salts, it forms crystalline compounds. (4) Tannic acid, on the 
other hand, is an amorphous substance and does not produce cry" 
line compounds with the salts mentioned. (¢) Therefore, the cys 
line compound found in the galls examined by the author is 12 
probability gallic acid. This appears to be formed at the mee 
of the starch during the chrysalis stage of the insect. Mage 
maturing of the winged insect this is changed to tannic acid. ; 
transformation of gallic acid into tannin appears to be one of pee 
condensation of two molecules of the former with the loss 4 
molecule of water, as follows: 2C,H,O, (gallic acid) =“ pe 
(tannic acid) + H,O.— Henry Kraemer, Philadelphia College of 
Macy. . : 
