42 



Indiana University Studies 



and their extensions into Lower California. This is another 

 instructive instance of the nature of variation where two 

 different faunal areas meet. 



Andricus ribes, new species 



FEMALE. — Almost wholly black; mesonotum regularly shagreened; 

 parapsides the only thoracic grooves; depression at base of scutellum 

 undivided; abdomen about triagTilate; a brownish cloud in the cubital 

 cell. HEAD: Not as wide as the thorax; eyes protruding beyond the 

 cheeks; black, the mandibles yello^^'ish rufous; finely rugose, rougher on 

 the face, with a few, scattering, short hairs. Antennae brown, the basal 

 four or five segments yellow-rufous, brightest basally; pubescent; with 

 at least 14 seg-ments (material broken), first segment short, second 

 globose, third almost half again as long as the fourth. THOEAX: 

 Mesonotum black; regularly shagreened, almost naked of hairs; parap- 

 sidal grooves deep, continuous, gradually approaching closely at the 

 scutellum, widely divergent only finally at the pronotum; median groove 

 lacking; anterior parallel lines and lateral lines hardly indicated by 

 smoother areas; scutellum black, distinctly longer than wide, moderately 

 roughly rugose, a broad, smoother but not wholly smooth, slightly arcu- 

 ate depression anteriorly not divided into foveas; pronotum laterally 

 finely rugose, irregularly aciculate posteriorly, hairy, usually black, 

 sometimes with a rufo-piceous area; mesopleurae usually black, very 

 irregularly aciculate, hairy, a central area smoother, naked, sometimes 

 colored rufo-piceous. ABDOMEN: Almost wholly black, sometimes 

 tinged with dark piceous, ventral valves light rufo-piceous; almost 

 naked, a few hairs latero-basally, and hairs on the ventral spine; ab- 

 domen about triangulate, slightly produced dorsally, the second seg- 

 ment covering two-thirds of abdomen. LEGS: Yellowish rufous, parts 

 of hind coxse may be piceous black, tarsi brownish apically; pubescent, 

 tarsal claws fine, toothed. WINGS : Clear, ciliate on edge, veins hea\^^ 

 deep bro\\Ti; areolet of moderate size or smaller; cubitus not as hea\w 

 as the other veins, continuous to the basalis; radial cell open, the bound- 

 ing veins not quite reaching the margin; second abscissa of the radius 

 slightly curved, tip somewhat enlarged; first abscissa angulate, the 

 angle about 135", with a distinct infuscation; a limited, light brown 

 cloud in the cubital cell, prolonged into a more or less discontinuous 

 band parallel to the second abscissa of the radius. LENGTH: 2.2- 

 2.8 mm. 



MALE. — Very similar to the female, differing as follows: eyes 

 somewhat larger; antennae wholly brown; abdomen very slender, smaller, 

 rather long-pedicellate. 



GALL. — Spherical, berry-like, very succulent, green and more or 

 less translucent when fresh, bright red when very young; the surface 

 pebbled, with a few, small, projecting points. Shrivelling greatly upon 

 drying, becoming blackened, 4.-6. mm. in diameter; when drying upon 

 the twig, the galls become rather obconical in shape, remaining lighter 

 in color. Monothalamous, the cavity filling the whole gall, the wall of 

 tissue moderately thin, thinnest furthest from the point of attachment. 



