HYMESrOPTERA OP THE HAWAIIAN ISLANDS. 211 



20, Odynerus dromedarius , sp. nov. 



? . RobustuS;, subnitidus, subtiliter pubescens, puuetatus, 

 niger ; fronte rubro-maculato ; alis Isete cseruleis ; 

 clypeo leviter emarginato ; abdominis segmento primo 

 fortiter transverso, antice verticali, segmento secundo 

 fortiter tuberculato-elevato ; metathorace baud ru- 

 goso. 



Long. 15 millim. 



The head is rather closely and coarsely^ but not deeply, 

 punctured; the prothorax, mesothorax, and scutellum have 

 two systems of punctuation^ — one very fiae and close, the 

 other larger and sparing, — the larger punctures being 

 almost non-existent on the scutellum and postscutellum. 

 The metathorax is finely alutaceous, and bears a few 

 rather large, but not deep, punctures. The hind body is 

 finely and sparingly punctured to near the apex of the 

 second segment, where the punctuation becomes (and it 

 continues over the next three segments) coarse and rather 

 close. The wings are of a very beautiful bright blue 

 colour. The elevation of the second segment of the hind 

 body gives the insect a most remarkable appearance, the 

 summit of the '' hump" into which the segment is gathered 

 up appearing (when viewed from the side) to be abruptly 

 raised above the first segment by about a third the total 

 height of the segment. The pubescence (of a whitish 

 colour) is very fine and is dense enough to prevent the 

 surface from being very shining. 



A single specimen of this most distinctive insect occurred 

 in February on Mauna Loa, Hawaii, at an elevation of 

 about 4000 feet, near the crater Kilauea, flying in the 

 forest. Another (much dilapidated) specimen taken at the 

 same time and place, is probably coaspecific, but if so has 

 lost the beautiful colour from the wings. It is devoid of 



p2 



