WINGLESS REPRODUCTIVE TYPE OF TERMITES 595 
the parents are first-form adults the nymphs of all five castes 
may be found. 
R. flavipes is one of the smaller termites, the smallest adults, 
the workers, measuring only 5.5 mm. in length, the soldiers 
from 6 to 7 mm., and the winged first-forms, not including the 
wings, 6mm. After mating has occurred, the abdomens of the 
reproductive forms undergo the postadult growth, characteristic 
of all termites, and which is particularly marked in this genus, 
although less so than in many tropical genera. The first-form 
adults (queens) increase from a body length of 6 mm. at the time 
of maturity up to 14.5 mm., the second forms from 6 mm. to 
12 mm., the third forms from 6mm.to9mm. The size increase, 
although marked, is considerably less in males. Some loss of 
activity in the queens accompanies the increase in bulk. 
Development. The eggs are 0.6 to 0.7 mm. long, the newly 
hatched nymphs are 1.1 mm. in length, and although externally 
all alike, they are differentiated internally into two types: a) with 
large brain and large sex organs, giving rise to the reproductive 
castes, and, 6) with small brain and small sex organs, giving rise 
to the worker and the soldier. More exact data than we possess 
at present upon the molting and the later phases of development 
of this and other species are greatly needed. 
The first form of R. flavipes 
The first form has three well-defined phases of development: 
a) the nymphs of the first form, with long wing pads, creamy 
white body, and light brown or pinkish eyes; 6) the winged adults 
of the first form, with long wings, dark brown body, and black 
eyes, body length 6 mm., length to tip of wings 9 to 10 mm.; 
c) the older males and females of the first form, with enlarged 
abdomen, and the scales of the shed wings, length 6 to 14.5 mm. 
The nymph of the first form. Very soon after hatching (body 
length, 1.3 to 1.4 mm.) it may be seen that among the repro- 
ductive nymphs with large brain and large sex organs, there are 
’ For data concerning colonies in which the parents are second-form or third- 
form adults see Thompson and Snyder, 719. 
