Aculeate Hymenoptera. 255 



Fam. APID^. 

 Gen. LiTHUEGus. 

 Lithurgus cognatus. 



Female. Length 7 4 lines. Black, with ferruginous 

 pubescence on the apical segment of the abdomen. 

 Head rather wider than the thorax, closely punctured ; 

 the face covered with white pubescence, that on the 

 cheeks is of the same colour, but longer, and more 

 sparing ; the face with a transverse bituberculate eleva- 

 tion at the base of the clypeus ; an elevated ridge on 

 each side of the central tubercle, curving down to the 

 base of the mandibles ; the mandibles short, stout, and 

 bidentate ; the flagellum of the antennae obscurely ful- 

 vous beneath ; the labrum of a broad lanceolate form, 

 and fringed with ferruginous hair. Thorax : the pubes- 

 cence pale cinereous, that on the femora and tibiae is 

 of the same colour, that on the tarsi dark brown ; on the 

 basal joint of the posterior tarsi within, it is tinged with 

 ferruginous ; the posterior tibiee outside are roughened 

 with a multitude of short stout teeth or spines ; wings 

 hyaline, their nervures black. Abdomen : the apical 

 margins of the segments narrowly fringed with pale 

 ochraceous pubescence ; the apical segment as well as 

 the abdomen beneath clothed with bright ferruginous. 



Male. Similarly coloured to the female ; the tarsi 

 elongate, the posterior coxae and femora incrassate ; the 

 basal joint of the postei'ior tarsi has, in the middle within, 

 a tuberculate blunt flattened process ; the tibiae are very 

 stout, and slightly curved, 



Hab. Champion Bay. 



In the British Museum. 



Although both sexes are considerably larger than 

 Lithurgus rubricatus, described in my Catalogue of Hy- 

 menoptera, from North Australia, I am inclined to believe 

 this may be a finely developed form of the same species ; 

 the tubercle on the face of the female, which is rudimen- 

 tary in L. rubricatus, is the most marked distinctive 

 character. 



