KEVISION OF NEARCTIC TERMITES. 113 



The termite Anoplotermes fumosus Hagen of Mexico and Texas is 

 usually found in the colonies of other termites, or at least closely 

 associated with other termites in the same colony; the other termites 

 are species of Amitermes. This may be termed "social parasitism," 

 or another form of trophallaxis. 



At any rate, these biological facts of behavior are just as inter- 

 esting, even if due to trophallaxis, as they were when explained 

 psychologically under the fantastical theories of the o'lder writers, 

 which can now be exploded and decried. 



Sometimes, as abnormalities, fertile soldiers with wing pads occur 

 in colonies. Heath (1903) records such soldiers in the species 

 Termopsis angusticollis capable of laying fertile eggs, which later 

 hatched, and the nymphs developed into the normal castes. 



In the genus Kalotermes soldiers with wing pads have been found 

 to occur in colonies of a number of our Nearctic species. They are 

 not rare. It is not known whether they are normally fertile or not, 

 but probably not. 



In the genus Reticulitermes a rare abnormality has been found in 

 the species tibialis Banks. This might be termed a half-worker, half- 

 soldier, and was found in a colony near Missoula, Montana. The 

 head has the characteristic pigmentation of the soldier caste and is 

 slightly longer than the head of the worker. The mandibles are 

 tjqjically workerlike, but are extended. The labrum is worker-like. 

 This individual can not be regarded as anything more than a worker 

 of abnormal development. (Thompson and Snyder, 1919.) 



Among species in the various genera of termites there apparently 

 is a variation in the proportion of the soldier caste to the worker caste, 

 or, where no workers occur, to the nymphs of the reproductive forms. 

 In incipient colonies there are usually one or two soldiers to to 12 

 workers or nymphs, so the proportionate numbers probably also 

 vary with the age of the colony. Of course, the proportionate number 

 of the nymphs of the reproductive forms and young would not only 

 vary with the season of the year, but also with their incidental posi- 

 tion (depending on the weather) when the colony was broken into. 

 Also under the heading ''workers" may be included young of the 

 worker-soldier type; that is, either potential soldiers or workers. 

 Under the heading "nymphs" in the family Kalotermitidae this is 

 also the case, except in the genera Termopsis and Neotermes, where 

 the worker-like forms without wing pads are either potential soldiers 

 or wingless third form reproductive individuals. 



In the accompanying table, except in a few cases, only a fraction 

 of the entire colony is represented. 



