GALLA. GALLS. 



8s 



with a few sieve-tube-like 

 cells. Numerous crystals 

 of calcium oxalate of both 

 rhomboid and agglomer- 

 ated types are found and 

 the cell walls are nearly all 

 thickened by rich deposits 

 of tannin. The outermost 

 cells are smaller and have 

 thickened walls. 



Chemistry. — Tannic acid 

 up to 70 per cent, of the 

 best galls ; sugar, 3 per cent. 



Chinese and Japanese 

 Galls. — These are produced 

 on the young twigs of a 

 species of Sumac, Rhus 

 semialata, indigenous to 

 northern and northwestern 

 India and the Himalaya 

 chain, and also in related 

 species. The insects de- 

 posit large numbers of eggs 

 and would hatch a large 

 brood. In collecting, the 

 eggs or larvae are killed, 

 generally by the applica- 

 tion of steam. 



In general the galls may 

 be said to be very irregu- 

 larly egg-shaped, but all 

 sorts of shapes are to be 

 met with, the galls being 

 bladdery with irregular 

 projections and knobs, and 

 twistings and contortions. 



Fig. 12. — Galla. 

 Cross-section of an Aleppo 

 gall: A, Outer portion of gall; /, 

 mner portion; g, tannic acid and 

 masses; kd, crystal sacs; kf, iso- 

 lated crystals; st, stone-cells; />, 

 parenchyma; gk, starch (Mocller). 



In general they run in size 



