BIOLOGY OF THE TERMITES OF THE EASTERN UNITED STATES. 33 
being repeated coition. Termites are sometimes polygamous, at 
least in incipient colonies. The young queens care for the young and 
earry the newly hatched larve in their mouths to safer places in the 
nest when the colonies are disturbed. (Nymphs of the first form also 
have been seen performing this duty in old colonies.) The workers 
attend the larve in old colonies. 
In the life cycle of termites, however, there is so much variation in 
the development of the castes that it leads to a rather complex life 
history. Young are kept in a retarded, undifferentiated state and can 
speedily be turned into substitute reproductive forms of both sexes. 
These neoteinic royal individuals are used (1) as substitutes for the 
true royalty that have swarmed and (2) in splitting up the old colony 
into new and independent colonies. Fully developed nymphs of the 
second form are to be found in colonies in the spring. They never 
complete their normal development, which consists of the acquisition 
of wings and the mature pigmentation, but assume the characteristic 
pale straw color after the final molt. The sexual organs are developed 
after the acquisition of pigmentation. They become neoteinic repro- 
ductive forms, but always (?) remain in the parent colony. 
Each caste has a distinct function, there being a well-defined 
division of labor, which, however, is not strictly adhered to. Ter- 
mites properly represent the phenomenon of polymorphism, i. e., 
‘species in which one or both of the sexes appear under two or fier 
distinet forms,?” both sexes being equally polymorphic. 
THE LIFE CYCLE. 
THE METAMORPHOSIS—CASTE DIFFERENTIATION. 
The metamorphosis of termites, while formerly considered to be a 
contrastingly simple type of insect development, is in reality very 
complex; indeed, there may be said to be different types of develop- 
ment for the castes. In the development of the worker, as in the 
order Thysanura, there is no external change or metamorphosis, the 
freshly hatched worker larva being active and of the same form as 
the adult worker. In the development of the soldier, however, 
marked changes in form occur, the mature soldier, with pigm pated 
head and saberlike mandibles, eine developed fo a large-headed, 
white, workerlike larva (Pl. [X). The winged, pigmented, sexed 
adult is developed from. a small-headed, white larva, there being a 
still more radical change. However, what may popularly be termed 
the “antlike” form can be distinguished in all stages in the devel- 
opment of all the castes, hence termites can hardly be classed with 
insects with “complete metamorphosis’ as the true ants, where there 
@ Wheeler, W. M. Concerning the polymorphism of ants. Bul. Amer. Mus. Nat. 
Hist., v. 23, p. 50-93, 6 pls., January, 1907. See p. 50. 
