PROC. ENT. SOC. WASH., VOL. 22, NO. 6, JUNE, 1920 127 



Virginia and Massachusetts. 1 Nymphs of the first, second and 

 third forms at the proper season of the year pass through quies- 

 cent stages of comparatively short duration, during the final molt, 

 to their adult type. 



Prior to this final molt a series of molts have occurred, the 

 number varying with the caste; in case of Nearctic termites, 

 however, the definite number of molts necessary from hatching 

 to maturity is unknown. Nevertheless, it is known that nymphs 

 of the adults of the first form require a greater number of molts 

 before attaining maturity than do the workers or soldiers. 



In the case of the nymphs of the first and second reproductive 

 forms of species of Reticulitermes, there is an elongation of wing- 

 pads during development; in all castes the segments of the an- 

 tennae increase in number. During the final molt of all three re- 

 productive forms which occurs normally in the spring or summer 

 in the case of eastern species, the anal appendices are lost in the 

 female sex. Shortly after the molt, mature pigmentation is at- 

 tained. This quiescent stage apparently serves the same pur- 

 pose as the pupal stage of insects with a complete metamorphosis 

 or development, since the most marked changes, both external and 

 internal, take place during this molt. 



The whole period intervening between the fully developed 

 nymph of the first form and the maturely pigmented winged 

 adult is about one day and one-half to two days for individuals, 

 and about one week to ten days for the colonies, in case of species 

 of Reticulitermes in southeastern United States. 



A more detailed illustrated description of the quiescent stage 

 and final molt of nymphs of the first and second forms has already 

 been given in a previous paper, (Snyder, 1915). The manner in 

 which the skin is shed, the attaining of pigmentation, the influ- 

 ence of moisture, and peculiar abnormalities are all discussed. 



Comparison of the Development of Termite Nymphs with that of Nymphs of 



Aphids and Zorotypus. 



It is rather interesting to note that in the nymphal develop- 

 ment of aphids, unlike termites, the "intermediate" female repro- 

 ductive form, with short wing-pads, originates from a nymphal 

 form with long wing-pads, (Turner and Baker, 1915). From the 

 normal nymph ("pupa") with the usual type of wing pads there 

 develop a large series of different "intermediate" reproductive 

 forms; in some cases there being a loss of eyes and wing-pads or 

 the length of the wing-pads is reduced a reversion. 



In the case of Zorotypus hubbardi Caudell, as in termites, the 



1 Mature young third form reproductive adults were found in a colony of 

 R. flavipes at Chain Bridge, Va., May 6, 1920, (before the swarm) along with 

 mature young second form reproductive adults and mature winged sexual adults . 



