Ixxviii FAUNA HAWAIIENSIS 



On the other hand we find that the genus Eupebmis, which can adapt itself to 

 very varied hosts, attacking eggs, larvae, and pupae of other insects, and various 

 orders, e.g. Coleoptera, Hymenoptera, Diptera, Orthoptera and Neuroptera, in the 

 small limits of the islands, has produced an exuberance of species. 



But we must also make allowance for the minute size and hidden life of most 

 of the Parasitica, as compared with the comparatively obtrusive presence of the 

 Aculeata, rendering the latter so easy to collect. And still further, while the bees 

 and wasps are comparatively of large size, presenting obvious characters for specific 

 separation in sculpture and general appearance, as well as others afforded by the 

 genitalia, mouth parts etc., which are easily examined in larger insects, the minute 

 forms, included in the Parasitica, are much more difficult to discriminate. The closely 

 related species of Odynerns, inhabiting different islands, if reduced to the size of 

 Mymarids, and subject to post-mortem distortion, like these and the smaller Chalcidoids, 

 might in many cases prove impossible to separate. 



Of the 52 genera, that contain presumably endemic species, 17 are, so far as our 

 present knowledge goes, themselves endemic. While 10 of the 13 aculeate genera 

 are considered endemic, only seven of the 39 parasitic genera are so. This, however, 

 is not of any great significance, but merely indicates that in the larger Aculeata it 

 is possible and convenient to distinguish groups of Hawaiian species from one another 

 or from allied genera in other countries. 



Prosopidae. — All the Hawaiian species belong to a single genus NesopTOSopis, 

 which I made for these island forms, not knowing at the time that similar characters 

 existed in foreign Prosopis. Subsequently by a curious coincidence, when collectino- 

 in England, I discovered a bee, new to the English fauna, having the essential 

 characters of Nesoprosopis. This species is the Prosopis kricchbaiimeri of the 

 European lists. Although 1 have examined the structures in numerous European, 

 Australian and American' Prosopis, I have not yet found any other species allied 

 to this European form, nor, consequently, to the Hawaiian ones. It is greatly to 

 be regretted that the terminal segments, which exhibit such fine characters for specific 

 and generic separation, are generally entirely neglected by describers of Prosopidae, 

 so that for American and Australian species I have had to rely entirely on my own 

 observations. Possibly it will be found that the European P. kriechbauiueri, or others 

 allied to it, extend their range, like other insects, across Asia, and this would point to 

 an Asiatic' origin for the Hawaiian A^esoprosopis. There is no doubt that had 

 P. kriechbauiueri been handed to me amongst a collection of Hawaiian species, as 

 coming from the islands, I should not have hesitated to consider it as an endemic 



^ An excellent paper on these has been published by Mr C. W. Metz (Tr. Am. Ent. Soc. x.xxvii, p. 85) 

 since this paragraph was written. 



^ A species has now been discovered in China by Mr J. C. Kershaw. 



