DIDINEIS LUN1CORSIS. Ill 



first joint long, the three following short, the apical one longer, 

 armed at the apex with a bifid claw ; the intermediate and pos- 

 terior tibiae armed with two spines at their apex ; the posterior 

 femora with a small dentiform process beneath at their apex. 

 The abdomen ovate, acuminate at the apex in the female, trun- 

 cated in the male, with a small spine at the angles of the 

 truncation. 



I have followed M. Wesmael in separating the species from the 

 genus Ali/son, in which the neuration of the wings is different, 

 and the intermediate tibiae only armed with one calcar or spur at 

 their apex. 



1. Didineis lunicornis. 

 D. niger ; abdominis segmentis duobus primis rufis, tibiis tar- 



sisque quatuor posticis fusco-rufis, alarum superiorum fascia 



transversali fusca. Fcem. 



D. antenuarum articulo ultimo lunato. Mas. 



Pompilus lunicornis, Fabr. Ent. Syst. Suppl. 249. 21 ; Syst. Piez. 



194. 32. 

 Alyson lunicornis, Latr. Gen. Crust, el Itis. iv. 86. 



Van d. Lind. Obs. ii. 88. 1. 



Shuck. Foss. Hym. 207. 1. 



Dahlb. Hym. Europ. i. 142. 75 & 474. 



St. Farg. Hym. iii. 86. 1. 

 Alyson Kennedii, Curtis, Brit. Eat. xiii. t. 584 ? . 

 Didineis lunicornis, Wesm. Hym. Foss. Belg. 97. I. 



Female. Length 3| lines. — Black and shining; the head deli- 

 cately punctured ; the scape rufescent in frout, the flagellum 

 fulvous beneath ; the clypeus rufescent in front ; the mandibles 

 yellow, with their apex piceous. Thorax delicately punctured ; 

 the metathorax with an elongated triangular space at its base, 

 which is enclosed by an elevated ridge, within which it is 

 rugose; the sides obliquely striated; the wings slightly coloured, 

 with a transverse fascia crossing at the marginal cell and 

 extending halfway across the third discoidal cell ; the nervures 

 and tegulae rufo-testaceous ; the legs simple, with the knees of 

 the anterior femora, and the inside of the tibiae, as well as the 

 tarsi, of a testaceous yellow ; the intermediate and posterior 

 tibiae and tarsi rufo-piceous, the posterior tibiae rufescent 

 towards their base, their tarsi piceous, and the articulations of 

 the coxa? and trochanters fulvous. Abdomen : the two basal 

 segments, and sometimes the base of the third, red, with a tri- 

 angular sericeous spot on each side towards their margin, most 

 conspicuous on the second segment, but frequently obliterated. 



