WALSH DESCRIPTIONS OF N. AM. HYMENOPTERA. 107 



lated) abdomen and its pectinate claws. Exenterus, Hartig, as 

 described by Brulle, appears identical with Cteniscus, Hal., as 

 described by Westwood, having, as Brulle expressly asserts, 

 "small, simple claws" ; and yet on the very next page Brulle says 

 that Bxyston differs from Exeittei-us in the claws being sim- 

 ple ! ! {Hymen, pp. 320-1.) Wesmael, writing in 1854, seems 

 to be unacquainted with Cteniscus which was published in 1840, 

 for in his Synoptical Table he refers solely to Exenterus, and 

 says that that genus usually has pectinate claws. 



Cteniscus albilineatus, n. sp.— 6*?— Black. Head polished, the face 

 and the base of the clypeus with some minute, sparse punctures. Face 

 except the terminal foveae, a short, narrow orbit scarcely passing beyond 

 the antennae, cheeks, clypeus except its tip which is honey-yellow, man- 

 dibles except their teeth, and palpi, all white Antenna; § as long as the 

 body, brown-black, pale yellowish-brown beneath on their middle \. 

 Thorax polished, with very minute, rather dense punctures. Metathorax 

 subpolished and rugose, the carinate areas all present, save that the basal 

 is confluent with the central area, and the cross-carinae of the lateral 

 areae are absent. Hind angles of the lateral areas prolonged in a short, 

 robust thorn directed outwards and backwards. Tegulae, a spot before 

 them under the humeral suture, a line under the front wing, a transverse 

 spot on the anterior edge of the mesothoracic pleura, the anterior edge of 

 the collare, the presternum, the hind surface of the scutel, and the whole 

 of the metathoracic scutel, all white. Abdomen subopaque, densely and 

 minutely rugoso-punctate, subpolished towards its tip and the tips of the 

 joints. Joint 1 longer by half than wide, \ wider behind than before, its 

 anterior angles laterally prolonged in a short, robust tooth, its sides pa- 

 rallel on the terminal £, thence scarcely concave and slowly converging 

 to the basal tooth ; carinae distinct and acute nearly to the- tip. Joint 2 

 slightly longer than wide, \ shorter than joint 1 ; 3-8 slowly shorter and 

 shorter. Tip of 2-7 with a marginal white line, gradually stouter on 2-6, 

 on 7 very slender. Venter whitish. Four front legs pale rufous, with 

 their coxae and trochanters white. Hind legs black, with the 2d trochan- 

 ter, and the upper face of the coxae, white. Wings hyaline; veins black, 

 radius rufous; stigma black, its basal i whitish. Radial area with a pos- 

 terior angle of 120 . Areolet with its inner side ^ shorter than either of 

 the other two. Length 6*? -25 inch. Front wing o* ? .22 inch. 



One 6" ? ; $ unknown. It is possible that the compression of 

 the tip of the abdomen may be due to an accident, but it has not 

 that appearance. 



[This is very closely allied to C. annulipes, Cress., Trans. Am. Ent. 

 Soc. ii. p. 112. — Cresson.] 



