122 BULLETIN 108, UNITED STATES NATIONAL MUSEUM. 



TERMOPSIS ANGUSTICOLLIS Hagen and T. NRVADENSIS Hagen. 



For taxonomy, see pp. 11-15. 



Termopsis angusticollis Hagen and the nearly related nevadensis 

 Hkgen reach the farthest north of any North American termites and 

 also occur at great altitudes in the mountains of the Pacific Coast 

 region. These two species are very closely related and have prac- 

 tically the same distribution and habits; they were not distinguished 

 by the early writers, although, as early as 1874, Hagen separated 

 nevadensis as a variet}^ consisting of the small, dark forms from 

 Nevada. 



Baron Osten-Sacken (1877) noted the occurrence of termites in 

 California, stating: 



Termopsis angusticollis (or nevadensis Hagen) was frequently observed by me in 

 dead trunks and branches of Quercus agrifolia, near Santa Barbara, in February. 

 The specimens * * * were taken from a small trunk or root, completely riddled 

 by them. 



Heath (1903 and 1907) has described in detail the habits of Ter- 

 mopsis angusticollis in California. 



The colonies of these termites are to be found in the decaying wood 

 of logs and stmnps and are often of large size. In the forests they 

 cause the rapid disintegration of such wood into humus. 



During the final molt the females of fertile nymphs normally lose 

 the genital appendices. In egg-laying queens of the third form of 

 Termopsis nevadensis (with no indication of wing pads) genital 

 appendices were noted as present, though they are absent in the 

 winged queens of the first form. The castes of Termopsis, as do all 

 termites, pass through similar quiescent stages noted (Sm'der, 1915) 

 in the metamorphosis of species of Reticiditermes. 



On May 7 to 14, 1913, observations were made of the molting of 

 nymphs of the first form of nevadensis. It was found that the skin 

 is shed in 15 minutes; the skin breaks along the median dorsal line 

 of the thorax. Two and one-half to three and one-half hours were 

 required for the wings to expand. At the end of 12 hours the cas- 

 taneous pigmentation was attained, but the mature pigmentation 

 is not acquired for several da3^s. The insects are not ready for fhght 

 for some time (a week or 10 days) after the wings have been expanded 

 and the mature pigmentation attained. The specimens on which 

 these notes were made were reared in cages at Falls Church, Virginia, 

 but the colony was collected by George Hofer, on April 18, 1913, 

 in an old pine stump at Rogue River, Oregon. 



SWARMING. 



Termopsis angusticollis and nevadensis are nocturnal swarming 

 species; the winged adults are attracted to lights. Apparently these 

 strong flying species swarm over long periods, either in the late 

 spring or fall. Osten-Sacken (1877) writes: 



