HYMENOPTERA 75 



Two species described by the Rev. T. Blackburn, O. haivaiiensis and O. halea- 

 kalae, I have not been able to identify with any certainty, not having seen the 

 original specimens. Mr Blackburn very kindly sent me an example under the former 

 name, but it was quite clearly not the subject of his description. This example 

 belongs to the species I have called O. pterocheiloides, and is excessively closely 

 allied to O. congrtms. Smith. There is no trace of tuberculation on the second 

 segment of the abdomen, and this alone is sufficient to distinguish it from O. hazaaii- 

 ensis as described, but it is certain from the remarks made at the end of the de- 

 scription of O. hawaiiensis, that several species were included under that name. As 

 regards O. haleakalae I cannot refer it for certain to any particular one of the species 

 found on Maui. There is no doubt, however, that both these species will prove 

 referable to two of the species which I have described under new names. Possibly 

 O. hawaiiensis, Blk. is the same as my O. erythrognathus, and O. haleakalae, Blk. 

 as O. ecostahis. 



ANTHOPHILA. 



Obtusilingues. 



Nesoprosopis, gen. nov. 



Under this generic name I propose to separate certain bees which have hitherto 

 been referred to the genus Prosopis, although at present it is necessary to rely on ^ 

 characters for the separation. In all the species examined (and these comprise most 

 of the 52 species known to me) the 8th ventral segment is highly peculiar, and although 

 exhibiting great variety in detail, yet always maintains the same general form. Its 

 apex is always produced into an extremely long process, which on the ventral side 

 rises erect or suberect from the body of the segment. In its simplest form the 

 process is a delicate curved rod, expanded at the apex, or more usually bifurcated, 

 the bifurcations being more or less recurved. On its apical portion at least it is 

 clothed with long hairs. In many of the species the process is greatly expanded 

 dorso-ventrally, so that in extreme cases it may be nearly as wide as long, and the 

 apical bifurcations are also sometimes greatly expanded. All intermediate conditions 

 between this and the simple form may be seen in the various species known from 

 the islands. 



The extreme apex of the process is always exposed in life, showing beyond 

 the sixth segment, which is more or less compressed or carinate, and emarginate at 



10 — 2 



