REVISIOISr OF NEARCTIC TERMITES. 121 



The argentine ant (Iridomyrmex Jiumilis) is a great enemy of ter- 

 mites in New Orleans, Louisiana, according to Father A. Biever. 



At the time of the annual swarm, ants kill and carry away many 

 winged termites, 



Beebe (1918) states that termites are immune to attack by the 

 army ants of the Tropics. 



BIOLOGICAL NOTES ON THE DIFFERENT SPECIES. 



Family KALOTERMITIDAE Banks. 

 Subfamily Termopsinae Holmgren. 



Genus TERMOPSIS Heer. 



The genus Termopsis Heer includes species among the most primitive 

 and the largest of our North American termites. But although large, 

 they are among the least destructive of our native species. There are 

 but few records that these termites have injured either the woodwork 

 of buildings, healthy living trees and other growing vegetation. 



M. W. Gorman, Curator of the Forestry Building, Portland, Oregon, 

 wrote on April 11, 1918, that termites had damaged the beams in that 

 building. The insects were not active after the winter till the first 

 week in April; they swarm in July or early August in great numbers. 

 The termite was T. angvsticollis. 



None of the species are subterranean in habit, living in the (usually 

 decaying) wood of logs, stumps, and dead portions of living trees, 

 usually in conifers, since these predominate in the regions where most 

 species of Termopsis occur, but the wood of deciduous trees is also 

 infested. The burrows usually follow the grain, except in badly 

 disintegrated wood and the wood is "honeycombed." (PI. 16, fig. 2.) 

 The pellets of excrement are more or less regularly impressed (pi. 9), 

 and are often found in moist matted lumps in old burrows or they are 

 expelled from the nests and fall to the ground. 



Old, long-established colonies contam several thousand individuals. 

 Species of Reticuliterme's sometimes inhabit the same tree or log as 

 Termopsis. Moisture is necessary for both these genera of termites. 



All of our native species of Termopsis swarm at night and are strong 

 fliers. 



The castes in the genus Termopsis are soldier, a worker-like repro- 

 ductive nymph with greyish-brown pigmentation, and the reproduc- 

 tive individuals of the three forms. There is no true worker caste, 

 but the duties of the workers are often performed by the nymphs of 

 the fertile third-form adults — large, worker-like, greyish-brown 

 forms, with no wing pads. 



The soldiers are large-mandibled and of a very formidable appear- 

 ance. They vary greatly in size in the colony. 

 110162— 20— Bull. 108 ^9 



