HYMfiNOPTERA. 247 



pendage. The antennae are filiform in both sexes. The inner side 

 of the mandibles presents, at most, a slight projection *. 



6. We now come to Fossores, in which the labrum is also com- 

 pletely or partially hidden, where the maxillae and labium form no 

 proboscis, where the inner side of the mandibles exhibits no emar- 

 gination, where the head is of an ordinary size, the abdomen is trian- 

 gular or ovoido-conical, and becoming- gradually narrower towards 

 its extremity, and never placed on a long pedicle. The antennae are 

 filiform and their first joint but slightly elongated. They are our 

 Nyssones. 



In some the eyes are entire. 



ASTATA, Lat. DiMORPHA, /zw., 



Where there are three closed cubital cells, all sessile, the second of 

 which receives the two recurrent nervures ; the radial has an appen- 

 dix, the extremity of the mandibles are bifid, and the eyes closely ap- 

 proximated superiorly |. 



Nysson, Lat., Jur., 

 Where the superior wings also have the same number of cubital 

 cells, but where the second is petiolate, and where the radial has no 

 appendix. The mandibles terminate in a simple point and the eyes 

 are distant |. 



OxYBELUs, Lat., Jur., Oliv., 

 Where there is but one closed cubital cell, receiving a single recur- 

 rent nervure. The antennae are short and contorted, and the second 

 joint is much shorter than the third. The mandibles terminate in a 

 simple point. The scutellum offers one or tliree dentiform points. 

 The tibiae are spinous, and the extremity of the tarsi presents a large 

 pellet. The females make their nests in the sand, and provision their 

 larvae with the bodies of Muscides §. 



NiTELA, Lat., 

 Likewise with but one closed cubital cell, but where the antennce are 

 longer, almost straight, and their second and third joints are of equal 

 length. The mandibles terminate in two teeth ; there are neither 

 points on the scutellum nor spines on the tibiae ; the tarsial pellet is 

 very small ||. 



The eyes are emarginated in others, as in 



PisoN, Spin., Lat., 

 Three closed cubital cells in the superior wings, the second very 

 small, petiolate, and receiving the two recurrent nervures, a charac- 

 ter which approximates the subgenus to Nysson ^. 



7. The last division of the Fossores, that of the Crabronites, only 

 differs from the preceding one, inasmuch as these Insects, which 



* Lat., Gen. Crust, et Insect., IV, 72. 

 t Lat., Ibid. 67. 

 X Lat., Ibid. 90. 



§ Lat., Ibid., 77 ; Encyc. Method, article Oxihele. 

 II Lat., Gen. Crust, et Insect., IV, 77. 



"II Lat., Ibid., 75, genus Tachybulus; and_387; genus Fison of Spinola, and not of 

 Jurine. 



