DEVELOPMENT OF CASTES OF TERMITES. 



395 



seated causes, I am inclined to believe, for several reasons which 

 follow, that Bugnion's account of the newly hatched soldier 

 (nasutus) nymph of .E. lacustris may be capable of a different 

 interpretation. 



First, the conditions among the newly hatched and the younger 

 developing phases of the nine termite genera here described are 

 practically similar, showing that throughout the entire order of 

 termites the early development is remarkably constant. 



Second, I have examined the newly hatched and the developing 

 nymphs of three species of Reticulitermes R. flavipes, R. virginicus 

 and R. n. sp. -and also of three species of Eutermes E. pilifrons, 

 E. morio and E. sanchezi and in each case the development of 

 the three species is similar throughout the early phases and as 

 far as I have followed it. It seems probable, therefore, that 

 E. lacustris would follow the plan of development that is common 

 not only to three other species of its genus and to three species of 

 Riticiditermes, but to seven other genera. 



FIG. 10. Eutermes pilifrons, newly hatched nymph, profile view, la, labrum; 

 Ib, labium; br, brain. Oc. 6, obj. 16, reduced one half. 



Third, in all the newly hatched nymphs of Eutermes, whether 

 pilifrons, morio or sanchezi, the labrum, as stated above, is long 

 slender and conspicuous. In nymphs seen in profile the side 

 view of this labrum is surprisingly like the frontal process or 

 "corne frontale" of a nasutus. In studying the younger Euter- 

 mes nymphs in alcohol I remarked again and again the length 

 of the labrum and its resemblance, especially in profile view, to 

 the frontal process of a nasutus. This is also true of the other 

 two genera of the Metatermitidae here described, Anoplotermes 

 and Amitermes. 



