170 



Dldyophorodelpliax. Dr. R. C. L. Perkins revised the 

 family in his interesting Introdnction to the Fanna Hawa- 

 iiensis in 1913. Noteson captnres and life histories have 

 appeared in the Proceedings of this Society at varions times 

 (1905 to date). These references, along with this present 

 paper, constitnte the whole of the literature of the autochtho- 

 nous genera of the Hawaiian Delphacidae. 



In dividing the species into genera Kirkaldy used charac- 

 ters already in use in continental areas and gave them the 

 same values. An examination of the male genitalia discloses 

 the fact that this system brings together heterogenous forms 

 and separates several allied forms. By using the size of the 

 first joint of the antennae, instead of the condition of the 

 frontal carinae, for primary divisions these forms are brought 

 together. Lelalolia and Nesodryas have the first joint of an- 

 tennae very short and wide, and are composed of very closely 

 allied forms, whereas the rest of the Alohini have the first 

 joint longer than wide and form a larger group of allied 

 forms containing several well-defined smaller groups, the exact 

 relationship of which it is difficult to decide. In the table 

 of genera Proterosydne is included, as it is the only foreign 

 genus of the tribe, with one American and one Australian 

 species. For specific characters the ultimate appeal is made 

 to the external male genitalia. Owing to the variability of 

 color in many species and the tendency of the females to im- 

 maculacy, the females of many species are difficult to sepa- 

 rate. For this reason I have refrained from erecting new spe- 

 cies on females, although there are several in the collections 

 that are undescribed. One specimen collected by Swezey at 

 ISTahiku, INIaui, has a single frontal carina, but otherwise it 

 is identical with Nesorestias; thus it constitutes another genus. 



Kirkaldy's sub-genus Leialoha I have separated, as a 

 genus, from Aloha, leaving the latter with ipomoeae and myo- 

 poricola and placing with them Nesopleias artemisiae, N. dii- 

 hautiae and several new species. Nesopleias nimbata I have 

 placed under Nesoi-edias, as they only differ in the greater 

 reticulation of tcgmina, a character I do not consider as of 

 generic value. The difference between Nesodryas and Neso- 

 thoe is, at most, only of sub-generic value; the type of the 

 former (N. freycinetiae) is not typical of the other species, 

 but is an extreme form, either divergent or convergent. 



While working on material from the Hawaiian Islands 



