BIOLOGY OF THE TERMITES OF THE EASTERN UNITED STATES. 43 
Freshly molted, immature, pigmentless nymphs of soldiers of 
Termopsis angusticollis , obtained from material collected by B. T. 
Harvey at Ashland, Oreg., August 28, 1913, show the same stages of 
development. In conclusion, therefore, it may be stated that in case 
of Leucotermes spp. and Termopsis angusticollis the differentiation 
occurs during a molt and quiescent stage rather late in the life cycle 
of the insect, the larvae having belonged to all external appearances 
to the undifferentiated group. 
SEASONAL VARIATIONS IN THE COLONY. 
There are wide differences in the composition of colonies of Leuco- 
termes at various seasons of the year. 
EGGS. 
In well-established colonies of flavipes, eggs and newly hatched or 
young larvae have been found by Hubbard, in Florida, in April, May, 
and June; by the writer, in Virginia, in April, May, June, July, August, 
September, and October; in Illinois, in August; and by Odenbach, in 
Ohio, in September. In incipient colonies, the first eggs are laid, in 
Virginia, by the middle of June or July in case of flavipes and in July 
or August in the case of virginicus. In well-established colonies of 
virginicus, in Virginia, eggs have been found in late May and early 
June. In cases of artificial nests or colonies of flavipes, kept under 
observation indoors, and in cases of infested buildings, eggs have 
been found by Odenbach and the writer in January, February, 
March, April, May, July, August , September, November, and De- 
cember. Odenbach's nests were from South Brooklyn, Ohio. 
In case of both flavipes and virginicus, in long-established colonies 
the period of maximum egg production is from the middle of May to 
early September in Virginia; that is, during the warm months. 
NYMPHS OP REPRODUCTIVE PORMS. 
Nymphs of the first form of flavipes with easily discernible wing 
pads were found in the quiescent stage of the molt on August 5, 1913, 
at Veitch, Va. By the middle of September they had well-devel- 
oped wing pads — two and one-half times the segment from which 
they originated — and antennae with from 16 to 17 segments. The 
nymphs were from 5.5 to 6.5 millimeters in length and the compound 
eyes had acquired the primary reddish pigmentation. There is 
apparently an unaccountable annual variation, since in 1913 and 
1914 nymphs were very abundant in colonies in the fall, while in 
1912 they were comparatively scarce. In March, up through the 
time of molting, nymphs of the first form are present in the out- 
lying channels of colonies in great numbers. 
