326 M. W. R. de V. GRAHAM 



long as or slightly longer than the pedicellus, second and following segments quadrate, or the 

 fourth to the sixth sometimes very slightly transverse ; clava two-segmented, subconical, 

 about 2-3 times as long as broad, hardly longer than the combined length of the two preceding 

 funicular segments ; the flagellum is clothed with quite strongly outstanding bristly hairs 

 whose length about equals the breadth of the segments which bear them ; the hairs are arranged 

 in two or three irregular rows on each segment. 



Propodeum longer, medially more than one quarter the length of the scutellum, and about 

 as long as the frenum. 



Gaster strongly compressed, about as long as but much narrower than the thorax. 



This is a rather isolated species, though in some respects it seems to be near 

 puncticollis (Thomson). It may easily be recognized by the combination of the 

 polished mesopleuron which lacks a mesepimeron ; the thickly hairy propodeal 

 callus, dorsal surface of the hind coxae, and mid lobe of the mesoscutum ; polished 

 propodeum which lacks a median carina and plicae ; and the relatively long flagellum 

 and funicular segments. 



Holotype $. Scotland : West Inverness, Isle of Rhum, Kinloch, 29.viii.1961, 

 beaten from foliage of Betula sp. (Graham), in Hope Department, University Museum, 

 Oxford. 



Paratypes. Same data as holotype, <JcJ, $$ ; Wester Ross, Badachro, 4 <$, 2 $, 

 20.viii.1953, taken when beating foliage of Quercus and Betula (Graham), in BM(NH), 

 Universitetets Zoologiska Institutionen, Lund and in Graham collections. 



Biology. Unknown. 



Gastrancistrus walkeri sp. n. 



$. Resembles indivisus sp. n., but differs especially in having shorter antennae and propo- 

 deum, more sparsely pilose propodeal callus and hind coxae. POL slightly greater relative to 

 OOL. The differences are given in more detail, as follows : 



Mid and hind tibiae, except their bases and tips, fuscous to black ; fore tibiae, and fore tarsi 

 dorsally, often more or less infuscate. Smaller species 1-35 to 1-7 mm. POL about twice 

 OOL. Eyes slightly smaller, separated by slightly less than 1 -5 times their own length. Genae 

 slightly curved. Vertex rather more glossy. Antennal scape slightly shorter than an eye ; 

 combined length of pedicellus and flagellum slightly less than breadth of head ; pedicellus 

 slightly longer than anellus plus first funicular segment ; all funicular segments slightly trans- 

 verse, the first slightly shorter than the others ; clava as long as the three preceding funicular 

 segments together. Propodeum medially at most slightly more than one seventh as long as 

 scutellum, with a median carina more or less indicated ; callus with two to four bristles only. 

 Metapleuron alutaceous ; mesopleuron with traces of alutaceous sculpture. Hind coxae hardly 

 twice as long as broad, with rather more distinct alutaceous sculpture than in indivisus, their 

 dorsal surface with a few hairs in the basal half only. Fore wing with costal cell rather nar- 

 rower ; speculum open, or partly closed below by a line of hairs. 



o*. Differs from that of indivisus as follows : 



Tibiae tending to be darker (asin$). Size less (1-2 to i^mm.). Antennae with first funicular 

 segment distinctly shorter than the pedicellus, usually slightly transverse though sometimes 

 quadrate, remaining funicular segments slightly transverse ; clava slightly longer than the 

 two preceding funicular segments together. Median carina of propodeum more or less indicated. 

 With regard to the ratio POL : OOL, size of eyes, curvature of genae, pilosity of propodeal 

 callus and of hind coxa, sculpture of meta- and mesopleuron, it resembles the female, and differs 

 from the male of indivisus in these respects. 



