OF WASHINGTON. 29 



Head smooth, not tridentate, without distinct antennal furrows; 

 antennae inserted close to the mouth, in 9 IO ' in rT i2-jointed, 



Spalangia Latr. 



ISOCRATUS Forster, Hym. Stud., ii, p. 53 (1856). 



Syn. Asaphes Walk., Ent. Mag., ii, p. 151 (1834). 



(Type A. vulgaris Walk.) 



Head transverse, wider than the thorax, with the frons impressed ; 

 viewed from in front it is subtriangular. Eyes moderate, broadly oval, 

 bare. Ocelli on the vertex, triangularly arranged. Mandibles curved, 

 bidentate, the teeth rather long, acute. Maxillary and labial palpi 2- 

 jointed. 



Antennae clavate, i2-jointed in both sexes, inserted slightly below the 

 middle of the face, all the funiclar joints transverse. Thorax sub- 

 ovoid, the pronotum large, nearly quadrate ; the mesonotum with two dis 

 tinct furrows, the parapsides subconvex, the metanotum small, rugulose. 



Wings hyaline, the margins delicately fringed, the marginal vein shorter 

 than the stigmal vein, the former slightly thickened towards apex. Legs 

 slender, the tibial spurs i, i, i, the last pair weak; tarsi 5-jointed. 



Abdomen ovate, depressed above, distinctly petiolated, terminating in a 

 small compressed process, the second segment about i^ times as long as 

 the third, the following segments short, subequal. 



Only a single species, having several synonyms, is known, as 

 follows : 



I. vulgaris Walker. 



Asaphes vulgaris Walk., Ent Mag., ii, p. 152. 



Ann. and Mag. Nat. Hist., x, p. 114. 

 List. Brit. Mus. Chalc. 1846, p. 23. 



Eurytoma aenca Nees, Hym. Ich. Aff. Monog, ii, p. 42. 

 Colax aphidii Curt., Jour. Roy. Agric. Soc. , iii. 

 Pteromalus petiolatus (?) Zett, Ins. Lapp., xiv, p. 332. 

 Chrysolatnpus suspensus Nees, Monog., ii, p. 127. 



altiventris Nees, 1. c. 

 Isocratus vulgaris Thorns., Skand. Hym., iv, 208. 



Riley, U. S. Agric. Rep. 1889, P- 35> P 1 - vi > f - 2 - 



$ 9- Length, 1.6 to 2.3 mm. Aeneous black and most frequently with 

 a decided metallic tinge on the thorax, pleura and coxae ; antennae usually 

 black, but the flagellum varies from brownish-yellow to brown and black, 

 legs, except coxae, brownish-yellow with sometimes the femora and tibiae 

 obfuscated; coxae aeneous black or submetallic; wings hyaline, the 

 venation pale brownish-yellow, the marginal vein shorterthan the stigmal 

 vein, a little thickened at apex. 



The whole surface, except the middle mesothoracic lobe anteriorly 

 and the metathorax, is smooth, shining; middle mesothoracic lobe 



