396 CAROLINE BURLING THOMPSON. 



In my Fig. 10, the profile view of a recently hatched worker- 

 soldier nymph of E. pilifrons, the resemblance is very striking 

 to Bugnion's figure 12 (1912), the profile view of the form which 

 Bugnion has described as a newly hatched soldier nymph of 

 E. lacustris. The long labrum, la, might have been taken for 

 the "corne frontale," the dark stippled mass, br, which repre- 

 sents the brain as seen through the transparent skin of the head, 

 might easily be mistaken for the frontal gland that is shown in 

 Bugnion's figure in about the same position. The duct of the 

 frontal gland figured by Bugnion might prove to be the esophagus, 

 which passes forward as a slender tube beneath the brain. 

 Furthermore, the frontal gland as figured by Bugnion in the 

 newly hatched soldier (nasutus) of E. lacustris is much larger 

 and more highly developed than in the older nymphs of -E. 

 pilifrons 2 mm. long, and is also larger and more developed than 

 I have found it in any newly hatched termite nymphs that I have 

 studied. As a rule this gland is not distinguishable at the time 

 of hatching except in sections, and even then is extremely small 

 and difficult to determine. 



Fourth, Professor Bugnion's figure was drawn from an un- 

 stained specimen, mounted, as he states, in either water or weak 

 formol, and studied as a transparent object. If after staining 

 and sectioning the same results are obtained in the newly hatched 

 nymphs of E. lacustris we should then have positive proof that 

 development varies in the different species of a termite genus 

 and that some castes may be fully differentiated at the time of 

 hatching. But, until this proof is established, the writer is inclined 

 to believe that development is a constant process among the dif- 

 ferent species of termites, and that it takes place as in the termites 

 here described. 



SUMMARY. 



The termites described in this paper are : 

 PROTERMITID^ 



Termopsis angusticollis. 

 Calotermes n. sp. 

 Cryptotermes cavifrons. 

 Neotermes castaneus. 



