498 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



XENOS AURIFERI, new species. 



Host. — Polistes aurifer Saussure, Palo Alto, California. Described 

 from one female collected in February, 1892, by W. G. Johnson, and 

 received from Prof. Henry Comstock. 



Female. — Length of cephalothorax 1.24 mm., breadth at spiracles 

 J..41 mm., breadth at base of head 1.08 mm., distance between mandi- 

 bles 0.29 mm. Cephalothorax dark brown on basal half, light yel- 

 lowish brown on apical portion, the lighter shades run back on the 

 margins in a narrow line almost to the spiracles, and also cause a 

 semicircular emargination of the dark area on the middle of the disk. 

 Cephalothorax broader than long, constricted at base, margin almost 

 perfectly convex, with only two long shallow emarginations in front 

 of the mandibles; spiracles not reaching lateral margin; mandibles 

 quadrate, emarginate at apex. 



Type.— Cat. No. 13699, U.S.N. M. 



Genus BELONOGASTECHTHRUS, new genus.. 



Name derived from Belonogaster (the host genus) + k%dpbc (enemy), 

 meaning a parasite of the genus Belonogaster. 



Type of genus — B. zavattarii, new species. 



The genus is restricted to parasites of Belonogaster and is at present 

 confined to Africa. 



Male unknown. 



Female. — Based on the figure by Zavattari (1909). 



Triungulinid. — Length 0.32 mm. Head large, dark, eye spot 

 dark. Head not half as long as thorax. Coxge large, femora and 

 tibice slender, tarsus a broad one-jointed transverse pulvillus, three 

 times as broad as the tibiae. First eight abdominal segments normal, 

 ninth elongate and emarginate for tenth which bears two long 

 stylets, and the lateral lobes of the ninth bear each a more slender 

 stylet. 



BELONOGASTECHTHRUS ZAVATTARH, new species. 



Host. — Belonogaster elegans Gerstaecker; Butiti, Congo Free State, 

 collected by the expedition of Due d'Abruzzi, and figured by E. 

 Zavattari (1909). Triungulinids were kindly presented the writer 

 by Doctor Zavattari. 



Female. — Cephalothorax about as long as broad; sides convex, 

 margin of head sinuate, apex lobately rounded. 



Genus PSEUDOXENOS Saunders. 



Leionotoxcnos Pierce. 



On account of a decision by Mr. S. A. Rohwer, of the U. S. National 



Museum, to consider Leionotus, Ancistrocerus, etc., as merely species 



groups of Odynerus, as was done by Saussure, it is expedient for the 



present to combine the genus Leionotoxenos with Pseudoxenos, espe- 



