386 



CAROLINE BURLING THOMPSON. 



those of the other Protermitidse here described, is long slender 

 and reniform, and measures 1.2-1.3 mm. in length (Fig. I, c). 



The newly hatched nymphs are 1.4-1.6 mm. long and have 

 nine antennal segments, the third segment entire and bare. 

 These nymphs are externally all alike, but are differentiated 

 internally into the reproductive type with large brain, and large 

 sex organs (Fig. 4, a), and the soldier 1 type with smaller brain 

 and smaller sex organs (Fig. 4, b). 



The peculiar truncated head and the characteristic form of the 

 antennae of this species are recognizable, even in the newly 

 hatched nymphs. 



In nymphs which are about 2.4 mm. long the "small-headed" 

 and "large-headed" types are clearly seen. This termite, like 



FIG. 4. Cryplotermes cavifrons, newly hatched nymphs. A, head of repro- 

 ductive nymph with large brain; b, head of soldier nymph with small brain. Oc. 

 6, obj. 16, reduced one third. 



Calotermes n. sp., increases the antennal segments slowly, for 

 nine segments still occur in this older phase, although the third 

 segment is subdivided. 



Neotermes castaneus Burmeister. The egg of Neotermes, fig. 

 5, c, is large, measuring 1.6 mm. in length. In form it is slender 

 and reniform like the eggs of other Protermitidae. 



The youngest nymphs in my material, which is not very abun- 

 dant, are 2 mm. long and have ten antennal segments. Since the 

 majority of the termites here described have nine antennal seg- 

 ments when hatched and are only from 0.2-0.3 mm. longer than 

 the egg from which they have emerged, I believe that these 

 nymphs are very slightly past the age of hatching. An exami- 

 nation of the antennae gives further basis for this opinion, fig. 



1 The worker caste is lacking in the genus Cryptotermes. 



