HYMENOPTERA 187 



smooth and shining, except the petiole which is almost as long as 

 segments 3 and 3 united, and longitudinally striate or aciculate. 



Type. — Cat. No. 55S3, U. S. Nat. Museum. From Sitka, June 

 16; St. Paul Island (Fur Seal Commission). 



Genus Thestis Forster. 



THESTIS TRICINCTA sp. nov. 



Female. — Length 3.5 mm. ; ovipositor about half the length of the 

 abdomen. Polished black, except the petiole and second segment of 

 the abdomen which are opaque and coriaceous ; the abdominal seg- 

 ments 2 and 3 at apex are yellow, while the extreme apex of the fourth 

 segment has a testaceous tinge ; clypeus, mandibles, palpi, tegulae and 

 the anterior and middle coxae and trochanters are yellowish-white ; 

 rest of legs, except the front pair and the hind pair in part, ferru- 

 ginous, the front legs yellowish, the hind coxae and femora black, 

 their tarsi fuscous ; flagellum brown, yellowish beneath near base. 

 Eyes very large, convergent below and leaving no malar space. 

 Thorax with the parapsidal furrows distinct, converging and uniting a 

 little beyond the middle of the mesonotum. Metathorax constricted at 

 base, completely and strongly areolated. Wings hyaline, the stigma 

 and veins light brown. 



Type. — Cat. No. 5598, U. S. Nat. Museum. From Popof Island, 

 July 8; Unga, July 7. 



This is one of the genera placed by Forster in this group ; I think 

 it should be removed to the tribe Plectiscini. It seems to fall in 

 naturally between Symphylus and Eusterinx. 



Genus Aclastus Forster. 



ACLASTUS RUFIPES sp. nov. 



Fe?nale. — Length 3.2 mm. ; ovipositor shorter than the petiole. 

 Polished black : palpi fuscous ; legs, except hind coxa, ferruginous, 

 the tibial spurs and tarsi paler, the hind coxse black. Antennje 21- 

 jointed, brown-black, the pedicel yellowish, the first joint of the 

 flagellum more than thrice longer than thick, longer than the second. 

 Metathorax short, wrinkled and completely areolated, the areola hexag- 

 onal, wider than long, the petiolar area very long. Abdomen broadly 

 oval, smooth and polished, except the petiole which is longitudinally 

 striate. 



Type. — Cat. No. 5999, U. S. Nat. Museum. From St. Paul Island, 

 August 16 (Fur Seal Commission). 



