PTEROMALIDAE OF N.W. EUROPE 289 



third of the total length, the following tergites are very strongly transverse ; tips of ovipositor 

 sheaths not or hardly projecting beyond the last tergite ; ventrally, the hypopygium is not 

 clearly visible owing to overlapping of the tergites, but its tip appears to be situated somewhat 

 beyond the middle of the gaster. 



<J. Differs from the female as follows : 



Fore and mid femora infuscate over their basal half ; hind femora mainly fuscous. 



Antennae with scape as long as an eye, 4-5 to 4-8 times as long as broad, not broadened in its 

 upper half ; combined length of pedicellus and flagellum 1-35 to 1-4 times the breadth of the 

 head ; funicle nearly cylindrical, slender, proximally not or hardly stouter than the pedicellus, 

 its first segment 1-25 to 1-4 times as long as the pedicellus and i-8 to 2 times as long as broad ; 

 the following segments progressively a little shorter, but all, except sometimes the sixth, slightly 

 longer than broad ; clava not broader than the funicle, barely as long as the two preceding 

 funicular segments together, about 2-3 times as long as broad ; funicle clothed with hairs which 

 stand out at an angle of 45 to 6o°, the length of these hairs about equal to the breadth of the 

 segments which bear them ; sensilla sparse. 



Gaster very strongly compressed, almost knife-like, about as long as the thorax. 



The $ of alectus closely resembles that of fuscicornis Walker, which differs as follows : 



Clypeus more transverse, 3-1-3-3 times as broad as long, its anterior margin not denticulate, 

 or with at most a weak median tubercle. Antennae with combined length of pedicellus and 

 flagellum hardly equal to the breadth of the head ; funicular segments, except the first, quad- 

 rate or even very slightly transverse, the first slightly shorter than the pedicellus. Fore wing 

 with speculum open below, extending as a bare strip below the marginal vein as far as the 

 stigmal vein ; the space between the base of the postmarginal vein and the stigmal vein more 

 or less bare, at least on the upper surface of the wing ; marginal vein slightly longer, costal 

 cell with a row of only 4-5 hairs on its upper surface. Legs with coxae dark ; femora infuscate 

 at least over their basal half ; hind tibiae sometimes more or less infuscate. 



The <$ of alectus differs from that of fuscicornis Walker in the structure of its antennae (see 

 key to species) as well as in the characters mentioned above for the female. 



Type material. None found. From the description, however, I am certain that 

 alectus must be the species redescribed above. Walker described what he supposed 

 to be the male, but I am sure that he must have had the female before him ; the 

 latter has a short obtuse gaster and might easily be mistaken for a male. 



Britain : [the following are new records]. 



England : Buckinghamshire, Hell Coppice, near Oakley, 1 $, 1 $, 2.viii.i953 ; 

 Berkshire, Bagley Wood, 1 <$, 29.viii.1954 {Graham) ; Kent, " July, Birchwood " 

 (Walker MS.). Scotland : Mid Perth, Killin, 1 $, 24.vii.1954 {Graham). 



Biology. Unknown. 



Gastrancistrus dispar sp. n. 



(Text-fig. 209) 



$. Differs from that of alectus as follows : 



All coxae black with a slight metallic tinge ; femora fuscous, the fore and mid ones broadly, 

 the hind ones narrowly, pale at the apex. 



Inner angles of axillae neither smoother nor more weakly sculptured than the rest. 



The female differs from that of fuscicornis in having the space between the postmarginal and 

 stigmal veins hairy, the speculum not extended as a bare strip below the marginal vein, and in 

 having the axillae uniformly sculptured, their inner angles not smoother than the rest. 



