68 SYNERGUS TRISTIS. 



8. Stneegus NERV0SUS. 

 PL XII, fig. 4. 



Synerg%t,s nervosus, Htg., Germs. Zeits., ii, 197 ; Mayr, Verh. 

 z.-b. Ges. Wien, xxii, 713, 16 ; Thomson, 

 Opusc, 795, 5. 



— tibialis, Htg., Germs. Zeits., ii, 197. 



— nigricomis, Htg., 1. c, iii, 347 (?). 



Black ; the antennae fuscous, or fuscous with a testaceous tinge ; the 

 basal joints darker ; legs rufo-testaceous ; the coxa3, the anterior femora 

 at the base, the greater part of the posterior, and the hinder tibia? 

 fuscous or fuscous-black ; wings with the nervures pale fuscous. Front 

 coriaceous ; mesonotum finely transversely coriaceous, the keels 

 distinct. Second joint of the antenna? longer somewhat than broad. 



The $ similar in coloration, the second antennal joint broader than 

 long, the third joint curved in the middle and thickened at the apex. 



Length T5 — 2 mm., 2 — 2*5 mm. 



Differs from S. vulgaris and tristis in having the 

 antennae and hinder tibiae infuscated, and the radial 

 cellule is more sharply pointed at the apex. 



I have it from the galls of Andricus autumnalis and 

 A. callidoma, and Mayr reared it from the galls of A. 

 collaris. 



Sweden, Germany, Austria. 



9. Synergus tristis. 



Synergus tristis, Mayr, Yerh. z.-b. Ges. Wien, xxii, 715, 17. 



Black ; the legs testaceous, the front femora broadly fusco-brownish 

 at the base, the posterior for the greater part blackish ; the tibia? more 

 or less fuscous, the hinder darker than the anterior, which have usually 

 a testaceous tinge; antenna? fuscous, the 2 — 3 joints and the apical 

 (especially beneath) testaceous ; wings hyaline, with fuscous nervures ; 

 the radial cellule somewhat two and a half times longer than broad at 

 the widest part. Front and mesonotum coriaceous, the apex of the 

 mesonotum finely transversely striolate. Frontal lamina? moderately 

 distinct. Second antennal joint longer than broad. 



The $ has the antenna? lighter coloured than in the $ , the third 

 joint thickened, about one-fourth longer than the fourth. 



Length 1-5— 1-8, ? 1-5—2-5 mm. 



It is not easy to hit upon any very satisfactory 

 characters whereby to separate this species from 

 8. Tschehi ; generally the latter may be known by the 

 antennae being rufo-testaceous, and the tibiae not in- 



