BIOLOGY OF THE TERMITES OF THE EASTERN UNITED STATES. 35 
The antennae increase in the number of segments by the subequal 
division of the third segment a independent of the molts in L. luci- 
fugus Rossi. 
In the metamorphosis of the soldier, as has been shown by Grassi a 
{Calotermes flavicollis Fabricius and Leucotermes lucifugus Rossi), 
Knower b (Eutermes sp.), and Heath 6 (Termopsis angusticollis Wal- 
ker), there is a radical change from a large -headed larva to the 
soldier caste. This change takes place during c a quiescent stage. 
The worker, like the soldier, also develops from a large-headed larva ; 
that is, in the colony there are two types of larvae, the large-headed 
and small-headed, the former normally developing to workers and 
soldiers, while the latter become the reproductive forms. According 
to Grassi there are four molts in the development of the asexual forms 
of Leucotermes lucifugus, whereas the sexed forms pass through five 
molts. Holmgren states d that in Leucotermes the soldiers are 
polymorphic and originate e from at least five different larval stages, 
while the polymorphic workers originate from three different larval 
forms. The undifferentiated larvae present possibilities of develop- 
ment in all directions, but the development of Leucotermes shows 
that the breeding possibilities, while great, are by no means so great as 
in Calotermes. This would indicate progressive development toward 
stability, as is also indicated by the absence or rarity of neotenes and 
ergatoids in the more highly developed termites (Termes and Euter- 
a Grassi, B., and Sandias, A. Op. cit., p. 270. 
1* Op. cit. 
c Snyder, T. E. Loc. cit. 
^ Holmgren, N. Termitenstudien 3. Systematik der Termiten — Die Familie 
Metatermitidae. K. Svenska Vetensk. Akad. Handl., Bd. 48, No. 4, pp. 166, 4 pis., 
Uppsala and Stockholm, 1912. Blick auf dem mutmasslichen, stammesgeschicht- 
lichen Entwicklungsverlauf der Termiten, p. 129-153. 
« The recent discovery by McClung, Stevens, and Wilson (Wilson, E. B., Heredity 
and miscroscopical research: Science n. s., v. 37, No. 961, p. 814-826, May 30, 1913) 
of the association of an odd number of chromosomes, in the divisions of the spermato- 
cytes — that is, cells formed by the division of the "spermospore," the male germinal 
cell — with the determination of sex may also be applicable to caste differentiation in 
termites. Wheeler (Wheeler, W. M., The polymorphism of ants, with an account 
of some singular abnormalities due to parasitism: Bui. Amer. Mus. Nat. Hist., v. 23, 
p. 1-93, pis. 6, Jan., 1907), however, states, with reference to ants, that nourish- 
ment, temperature, and other environmental factors merely furnish the conditions 
for the attainment of characters predetermined by heredity, that is, with Weismann 
he believes that the characters that enable us to differentiate the castes must be repre- 
sented in the egg, but with Emery he believes the adult characters to be represented 
in the germ as dynamic potencies or tensions rather than morphological or chemical 
determinants. Holmgren states (op. cit., p. 140) that in termites, as the result of 
the method of feeding, three potential germ plasms are released in at least three direc- 
tions * * * and that there must be a germ plasm correlation which finds its 
expression in the caste correlation. 
