532 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



9. Thorax short, scutellum separated from mesonotum by a 



deep furrow 10 



Thorax more elongate, scutellum not separated by a deep 

 furrow II 



10. Face with a distinct keel between antennae 



Britrissomerus p. 534 

 Face not keeled Polygnotus p. 535 



11. Lateral ocelli nearer to eye margin than to anterior ocellus 



Platygaster p. 540 

 Lateral ocelli nearer to front ocellus than to eye margin 



Isocybus p. 541 



Isostasius Foerster. 

 °I. musculus Ashmead. 



Black, shining. Antennae piceous or dark brown. Legs 

 brown, coxae black, trochanters, base and apex of femora, tibiae, 

 and all tarsi honey-yellow. Thorax with hardly a trace of fur- 

 rows. Length 1.2 mm. 



Inostemma Haliday. 

 °I. horni Ashmead. 



Black, subopaque, closely finely punctulate; mesonotum shin- 

 ing. Antennae black, the pedicel and first two funicular joints 

 a little pale at tip. Parapsidal furrows complete. Legs black or 

 piceous, tarsi yellowish, and tibiae paler basally. Abdomen in 

 female at base with a horn extending over the thorax to the 

 vertex of the head. Male without horn. Length 1-1.4 mm. 



A parasite of a Cecidomyid forming galls on the iron-weed 

 (Vernonia noveboracensis), 



Amblyaspis* Foerster. 

 Key to Species. 



1. Scutellum produced into an acute spine minutus 



Scutellum triangular or with a tubercle at apex 2 



2. Abdominal petiole, legs, and base of antennae pale yellow 



petiolatus 



Antennae dark brown 3 



Antennae, except club of female, bright yellow flavicomis 



3. Abdomen broadly oval, shorter than thorax breviventris 



Abdomen long-oval, longer than head and thorax together 



antennariae 

 ° A. minutus Ashmead. 



Polished black, impunctate. Antennae and legs yellow or 

 reddish yellow. Scutellum acutely spined, yellow at tip, foveated 



* See note on p. 531. 



