112 BULLETIN 108, UNITED STATES NATIONAL MUSEUM. 



other members of the colony. Holmgren evolved an "exudat- 

 theorie" to show that there is a relationship between the amomit 

 of exudate tissue and the care that a termite receives, as licking 

 and feeding. Instead of the instinct to care for the brood, it is 

 desire for the exudation. Holmgren concludes that he regards the 

 exudate secretion not only (1) as the cause of feeding but (2) as the 

 cause of caste differentiation. The work of Miss Thompson (1917) 

 disproves Holmgren's second conclusion and also the whole subject 

 of "manufacture" of reproductive forms through feeding by the 

 workers. 



According to Wheeler (1918) this attribute of the parental feelings 

 of man to insects is termed "anthropomorphism" by the orthodox 

 behaviorists. In a remarkable paper on ant larvae Wheeler suggests 

 the term "trophallaxis;" that is, exchange of nourishment, for the 

 cooperative relationship between adults and larvae. Wheeler 

 further writes : 



Althovigh considerable evidence thus points to trophallaxis as the source of the social 



habit in wasps, ants, and termites, it must be admitted that the phenomenon has 



not been observed in the social bees. 



* * * * * * 



If we confine our attention largely to the ants, I believe it can be shown that tro- 

 phallaxis, originally developed as a mutual trophic relation between the mother insect 

 and her larval brood, has expanded with the growth of the colony like an ever- widen- 

 ing vortex till it involves, first, all the adults as well as the brood and therefore the 

 entire colony; second, a great number of species of alien insects that have managed 

 to get a foothold in the nest as scavengers, praedators or parasites (symphily); third, 

 alien social insects — i. e., other species of ants (social parasitism) ; fourth, alien insects 

 that live outside the nest and are "milked" by the ants (trophobiosis) ; and, fifth, 

 certain plants which are visited or sometimes partly inhabited by the ants(phytophily). 



In the termite colony the workers and 5"oung nymphs of the repro- 

 ductive forms may be seen carrying away eggs and yomig when the 

 colony is disturbed. They solicit exudation from the anus of the 

 queen, and also assiduously "clean" — that is, lick — over the bodies 

 of other workers or nymphs, brushing them with the maxillary palpi. 



When the colony is broken into, both workers and soldiers evi- 

 dence alarm when near the reproductive forms; that is, indulge in 

 convulsive jerky movements of the body — a method ^of communi- 

 cating news of the danger to other members of the colony ? 



At the time of the emergence of the winged colonizing adults 

 workers and soldiers eongregate near the points of emergence with 

 heads toward the exterior. 



Reproductive forms of termites are often minus an antenna or leg, 

 and nymphs of the reproductive forms sometimes have the wing 

 pads partially bitten off, also the prothorax at the base of the lateral 

 edges, possibly due to eagerness for exudate. 



Most of these actions or facts can be explained as due to " trophal- 

 laxis." In case of the bitten wing pads on the nymphs, this may be 

 merely incipient cannibalism. 



