REVISION OF NEARCTIC TERMITES. 93 



at the extremity of the prothoracic tibiae there is a chitinized area 

 on the dorsal surface. 



Workers of Constridotermes tenuirostris Desneux, 0. cinereus Buck- 

 ley and Reticulitermes Jiavipes Kollar, do not have a marked distinc- 

 tion between the tibiae of the prothoracic and mesothoracic legs, 

 although these termites are also earth-inhabiting. 



All subterranean or earth-inhabiting termites have a worker caste. 

 No termite which does not live in the earth has a worker caste, except 

 Prorhinotermes simplex Hagen. 



These subfossorial tibiae may be explained as "chance variations" 

 that have proven useful and have hence survived. 



On the famous expedition of Webster and Schaupp for Beaver 

 parasites, the late Prof. F. M. Webster found a colony of Constrido- 

 termes cinereus Buckley in a beaver's nest at Devil's River, Texas, on 

 March 23, 1891. In this case, of course, the termites were merely 

 taking advantage of a favorable situation for a nest. 



As Haviland states (1902) of species of " Eutermes" : 



* * * Long legs [longer than abdomen] and long antennae [fig. 54, 3] 

 [also a saddle-shaped pronotum] go with much walking and foraging [species of 

 Constrictotermes and Nasutitermes — the workers and soldiers of which are also pig- 

 mented and wander about above ground. Another peculiarity is that the worker is 

 larger than the soldier or nasutus (Consfn'cioiermes cinereus Buckley).] * * * Sol- 

 diers with short, stout legs belong to species sluggish in theii' movements, and which 

 venture but little from home. 



WOOD-INHABITING SPECIES. 



Our native wood-inhabiting species, which are not subterranean, 

 belong to both of the two families of Nearctic termites — that is, Kalo- 

 termitidae and Termitidae. Of the former, all of the subfamihes 

 and genera are in this group, that is, Termopsinae and Kalotermi- 

 tinae; genera Termopsis Heer, Kalotermes Hagen, Neotermes Holm- 

 gren, and Oryptotermes Banks. In the latter family only one species 

 of the subfamily Rhinotermitinae, namely, Prorhinotermes simplex 

 Hagen, is not subterranean. 



The species of Termopsis live in the moist, decaying wood of logs 

 and stumps, usually inhabiting regions where coniferous trees pre- 

 dominate. They never leave the wood to burrow in the ground and 

 they infest the wood directly through holes, under loose bark and 

 decayed areas. So far as is known they are not particularly injurious 

 species, which is unusual among termites. The pellets of excrement are 

 impressed — that is, slightly grooved or marked by longitudinal lines 

 (pi. 9); they are more moist and usually less regular than the 

 pellets of species in the subfamily Kalotermitinae, and are often 

 either massed together in the burrows or are expelled and fall to the 

 ground. 



Kalotermes, Neotermes, and Ci^yptotermes bore lengthwise through 

 the hard, dry wood, and, instead of following the grain, excavate 



