BENEFICIAL INSECTS 



65 



Cochineal, Lac, etc. — Of less value to man than the products 

 of the silkworm and the honeybee are cochineal, lac, tannic acid, 

 and medicines. The coloring matter known as cochineal is made 

 from a scalelike insect that lives on cactus plants in Mexico and 

 Central America. Lac is derived also from scale insects which 



Fig. 41. — A modern beehive. (Photo by Hegner.) 



occur principally in the Orient. It forms the base of many fine 

 polishes and lacquers of India, China, and Japan. Part of the 

 tannic acid used in the manufacture of leather is extracted from 

 the swellings on certain plants, called galls (Fig. 42), which are 

 caused by insects. The black coloring matter in some kinds 



