GALL A. GALLS. 83 



KAMALA. 



Kamala consists of the glands and hairs that cover the 

 fruit of Mallotus Philippinensis, a small tree of India and 

 neighboring countries. The tree produces capsular fruits 

 the size of a pea. These are completely covered by a red 

 powder, which is simply shaken off. 



Examined under the microscope, kamala will be seen to 

 consist of glands and hairs. The former are smaller than 

 lupulinum glands, possess a depressed, globular shape, are 

 filled with a red resin, and contain a number of club- 

 shaped secreting cells radiating from a common centre. 

 The hairs are thick- walled, curved, and are usually 

 arranged in small groups. 



Chemistry. — The resin of kamala has been separated 

 into six different principles: rottlerin, isorottlerin, two 

 resins, wax, and a yellow pigment. 



GALLA. GALLS. 



An excrescence on Quercus liisitanica and other species 

 of oak, caused by the puncture and ova of Cyntps gallcs 

 tinctoria. 



These are produced by the female insect, who deposits 

 her egg or eggs in a rapidly growing part of the plant, 

 where, by the irritation produced, the tissues of the plant 

 take on an abnormal and rapid growth, providing for the 

 larvai a place of refuge against foreign enemies and also 

 providing for them a store of food (the deposit of tannin 

 seeming to be an added means of protection to the insect*). 



After the larva has matured, it bores its way out of the 

 gall and goes on to complete its development outside. 

 (Unbored galls are preferred.) Up to the time of the 

 escape of the insect the gall is usually greenish; after 

 that it is apt to turn brown. 



♦ Adler: Deutsche entomolog. Zcitsch., 1887, 305, 352. 



