WALSH DESCRIPTIONS OF N. AM. HYMENOPTERA. l6l 



parapsidal grooves almost obsolete, the space behind the wings 

 about as long as that before them. Scutel subquadrate, flattish. 

 Metathorax subcubical, its sides a little convergent behind, the 

 carinate areas generally, except the posterior one, all distinct. 

 Abdomen subpetiolated, elongate-clavate d 1 , clavate 2, d 1 2 with 

 their sides nearly straight to beyond the middle, the tip of joint 5 

 d 1 , joint 6 2, being about the widest part. Joint 1 d 1 2 very long ; 

 joint 2 longer than wide ; 3-6 d 1 nearly square ; 3-7 2 shorter than 

 long and subequal. Venter unusally corneous, flattened, and with 

 a slight longitudinal carina ; anus 2 slit, as it is termed. Ovi- 

 positor about as long as the abdomen ; sheaths moderate, not ta- 

 pered. Legs moderate ; in all 6 legs 2 tarsal joints 3 and 4 very 

 short, and joint 3 acutely bilobate ; in the middle legs 2 tarsal 

 joint 2 likewise short, and the tibiae twisted as in Odontomerus 2 ; 

 in all 6 tarsi d 1 only joint 4 very short, and all the joints simple. 

 Both front and middle tibiae 2 inflated near their tip. Hind coxae 

 d 1 2 long and slender, and about as long and stout as the femora. 

 Spurs normal. Claws simple, moderately long, much longer than 

 the pulvillus. Wings moderate. Stigma and radial area elon- 

 gate. Areolet large, rhomboidal, its anterior angle often more 

 or less truncate. The 1st recurrent vein almost straight ; the 2d 

 recurrent vein biangulated. Bullae 4, B, C, D, and E ; B on the 

 posterior end of its vein, C close to the areolet, D between the 

 two angles of its vein, and E nearer to the tip than to the base of 

 its vein. 



Closely allied to Xorides, Grav., by its face narrowed below, 

 and to Odontomerus by the singularly twisted middle tibiae 2,. 

 which character is here subobsoletehy shown also in the front ti- 

 biae 2. Differs from all the other genera belonging to this group, 

 except certain Echthrus, viz., annu/icomis, n. sp., and ornatipentiis, 

 Cress., by the obsolete parapsidal grooves and the large areolet. 

 From Echthrns it is at once separated by the emarginate eyes, the 

 long clypeus, the singular structure of 2 legs, and the separation 

 of bullae C and D. The abdomen o* is not greatly elongate and 

 almost linear, as in Xorides o" and Xylonomus d 1 , nor has it the 

 tips of its joints emarginate as in Xorides d". Brulle - entirely over- 

 looked some of the most remarkable characters of this genus, e.g. 

 the face narrowed in front, the subcubical head, and the bilobate 

 3d tarsal joint 2, and confounded it with Mesochorus, Grav., 

 which appertains to an entirely different group, and has a trans- 



iii — II [June 9, 1S73.] 



