Vol. IV. January, 1903. No. 2. 



BIOLOGICAL BULLETIN. 



THE HABITS OF CALIFORNIA TERMITES. 



HAROLD HEATH. 



Situation of A T cst. - - Of the six species of termites inhabiting 

 the western part of the United States, three, Tcnnopsis angnsti- 

 collis Walk., Calotermes castancus Burmeist. and Termes lucifugits 

 Rossi, occur within one hundred miles of San Francisco. The 

 first named is by far the largest and is seemingly the most 

 abundant. At various points, for example the pine woods not 

 far distant from the Hopkins Seaside Laboratory at Pacific Grove, 

 colonies may be found in almost every stump and decaying log 

 and even dead branches on otherwise healthy trees are frequently 

 infested. As in the case of several other termites their excava- 

 tions follow more or less closely the grain of the wood and are 

 confined to its deeper portions, leaving an outer protective hull, 

 perforated at various points by tunnels leading from the interior 

 to extensive spaces beneath the bark where the eggs and young 

 are housed during the warmer hours of the day. No galleries 

 lead from the nest into the earth nor into adjacent regions as is 

 the case with Tcnncs and if for any reason a portion of a log con- 

 taining the royal pair be separated even by a few inches from the 

 remainder no intercommunication ever takes place and the latter 

 in due time produces substitute royal forms which maintain the 

 community. 



Calotermes castancns, scarcely more than half as long as the 

 above-described species, appears to be comparatively rare in the 

 central portions of the state. I have taken but two nests, one at 

 Pacific Grove and another on the Stanford University campus, 

 the first in a pine log also inhabited by Tennopsis though the 

 tunnels of the two did not communicate, the second in a eucalyp- 

 tus stump. Judging from these two colonies their habits are 



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