1901.] 265 



ratluM ilifferLMitly formed, and tlio llatteued spiiu's with which it is armed are in the 

 dark form short, about as long as the widtli of the flat surface ; in the hght form 

 elongate, twice as long as wide and dilated apically. 



Xylocopa (Biieipennin, de Geer, should be X. chloroptera, a correction already 

 made by Herr Alfken. 



In remarks on the EumenidcB, op. cit., p. 31, I stated that the measurements 

 were taken fi'om the head to the apex of the first abdominal segment. This is, of 

 course, a mistake, it being usual to measure these insects to the apex of the second 

 segment, as is indicated at the end of the diagnosis of the first species described. 

 The appended table of the Oahuan species of Odynerus enables me to correct 

 several mistakes in this genus, and to indicate two new genera and several new 

 species, which I hope to fully characterize in a subsequent part of the " Fauna 

 Hawaiiensis," together with other genera and species. Three species collected by 

 the Beechy expedition are herewith included, viz., two described by me for the first 

 time, op. cit., p. 74 (O. oblitus and O. relictus), and one described by de Saussure 

 from the same source (O. nautarum), the type of which is lost. With regard to the 

 other species brought back by this expedition, O. obscure-punctatus, Blackb., and O. 

 iiifaustiis, Perk., were pi'obably obtained on Hawaii, and O. sandwichensis, de Sauss., 

 on Maui and Lanai, the latter probably identical with O. rubrit incftts, Sm. ; de 

 Saussure's type in the British Museum not being forthcoming. Lay, the collector 

 for the Beechy expedition, was left on Oahu in ill-health and picked up on the 

 return journey, and this gave him ample time to visit the other islands, but whether 

 he did so I have no information. At any rate, I now feel sure that the above-named 

 species were not obtained on Oahu, but were collected elsewhere by Lay himself or 

 by others for him. 



Of the species included in the following table I may add that, excluding the 

 widely-spread O. nigripennis and O.frater, and possibly O. erro, all are peculiar to 

 Oahu, and it is improbable that any of them will be found on other of the islands. 



SYNOPSIS OF OAHUAN SPECIES OF ODYNERUS. 



1 (10) Thorax or abdomen or both with red markings. 



la {lb) Basal abdominal segment entirely red above, or at most a little infuscate, 

 2nd segment also largely or entirely red, as also the tegulse... 



O.frater, D. T. 

 lb {\a) Basal abdominal segment black with red apical margin. 



2 (7) Second ventral segment of abdomen greatly and abruptly raised behind 



the transverse sulcature. 

 Pi'othorax with red markings. 

 Second venti'al segment extremely strongly raised from sulcature, meso- 



thorax duller and more closely and regularly punctured... 



O. pseudochromus, Perk. 

 Second ventral segment less strongly raised, mesothorax more shining 



and irregularly punctate O. leiodemas. Perk. 



Prothorax and mesopleura without red spots {S unknown)... 



O. 2jaludicoIa, sp. nov. 

 Second ventral segment not strongly and abruptly raised behind the 



sulcature. 



