Isoptera 277 



tial hazard to the termite colony. A large colony will keep the fungi 

 eaten down, but a small colony is often unable to do so and the termites 

 themselves are attacked by the fungi. Precautions which may be taken 

 to prevent this are: (1) choice of wood for food which does not contain 

 excessive amounts of fungus mycelium, (2) frequent changes of the 

 food when an artificial diet is used, (3) avoidance of excessive moisture 

 in the food and of temperatures much above 20 C, (4) constant watch 

 for excessive fungous growth, and (5) prompt removal of diseased 

 termites. 



Colonies of damp-wood termites, as found in nature, are composed of 

 nymphs and adults. The adults are of two distinct castes, soldiers and 

 reproductives. There are two types of reproductives: primary repro- 

 ductives and supplementary reproductives. In some colonies a pair 

 of primary reproductives, founders of the colony, may still be present. 

 They may be distinguished by their brown bodies. In colonies from 

 which the primary pair has disappeared, and in groups of nymphs which 

 have become separated from the parent colony, some of the nymphs 

 develop into supplementary reproductives. The latter are caramel 

 colored. 



Either type of reproductive, if included in a laboratory colony, will 

 provide for the increase of the colony. Reproduction is carried on much 

 more rapidly, however, by the supplementary reproductives. In a 

 laboratory colony set up with nymphs alone, supplementary repro- 

 ductives will develop and become functional within 4 to 7 weeks after 

 the establishing of the colony. 



Primary reproductives, before they swarm, have wings. When these 

 alate forms develop in a laboratory colony, they are either removed 

 from the colony or allowed to swarm. If it is desired to start colonies 

 with primary pairs, the alates, as soon as they become fully pigmented, 

 are allowed to swarm in the laboratory. The covers are removed from 

 the containers, and the alates, which are positively phototropic, fly 

 toward a window or other source of light. After a few minutes they drop 

 to the floor and shed their wings. They are then picked up and males 

 mated with females for the founding of primary colonies. Males may be 

 distinguished from females by the smaller size of the posterior three or 

 four sternites. The growth of primary colonies, however, is very slow. 

 So for most purposes it is preferable to use nymphs alone or nymphs 

 and supplementary reproductives for establishing laboratory colonies. 



So far as I know, no one has succeeded in rearing termites from eggs 

 without the presence of adult termites or older nymphs to care for the 

 eggs and to groom and feed the young nymphs. I have found nymphs of 

 the 4th instar satisfactory for experiments such as those on nutritional 

 requirements. At that stage in development they are able to care for 



