PTEROMALIDAE OF N.W. EUROPE 463 



Forster (1856 : 64, 69) stated that the genus Metopum [=Psilocera] had 3 anelli 

 (Ringeln) in the antennae. Thomson (1878 : 166, " Anm.") refers to Forster's 

 statement and says that he has not himself seen any species of Metopon with 3 

 anelli. Of the species placed in Psilocera in the present work, one has 3 anelli, 

 whilst two have 2 anelli, in the female antenna. Males of all three species, however, 

 have 2 anelli. In the female Psilocera the segments of the flagellum tend to be 

 very closely compacted so as to be difficult to count, especially the anelli. In spite 

 of the difference in the number of anelli between the females of some species of 

 Psilocera, these species are so similar in other respects that their inclusion in a 

 single genus is justified. 



I am not sure whether any of the species referred to Psilocera by Peck (1963) 

 really belong to it. Metopon deiphon Walker, which he includes in Psilocera, 

 appears to be near Spaniopus or Trichomalus according to the type specimen 

 (Hym. 5. 693) in BM(NH). The original descriptions of the other two species, 

 Metapon californicum Ashmead and M. rufipes Ashmead, fit the characters of 

 Psilocera ; but I am acquainted with another North American genus very near 

 Psilocera, to which they might equally well belong. Ashmead did not mention the 

 characters which would allow one to decide the question. 



Key to European Species 

 (Females) 



1 Antenna (Text-fig. 341) with three anelli and five funicular segments, the 



third flagellar segment being without sensilla, not or hardly half as long as 

 the fourth segment, and quadrate or even very slightly transverse. 



Rather small species, length 2 to 2-7 mm. Basal cell of fore wing having 

 about its distal third pilose. Propodeal costula separated from base of 

 propodeum by hardly one third the total length of the propodeum. Anten- 

 nal scape mainly, sometimes also the pedicellus and anelli, reddish 

 (Metopon Walker). Gaster, Text-fig. 289 . . . atra (Walker) (p. 465) 



- Antennae (Text-figs. 339, 340) with two anelli and six funicular segments, the 



third flagellar segment provided with sensilla, at least about two thirds as 

 long as the fourth segment, and quadrate or longer than broad (Psilocera 

 Walker) ............ 2 



2 (1) Antenna (Text-fig. 340) with flagellum strongly clavate (the clava about 



twice as broad as the first funicular segment) its segments closely compacted ; 

 area of micropilosity on the clava occupying nearly two thirds its length ; 

 first funicular segment i-6 to 1-9 times as long as broad, as long as or a 

 little longer than the pedicellus. Large species, length 2-6 to 4 mm. Basal 

 cell of fore wing often having its distal half or more pilose 



crassispina (Thomson) (p. 466) 

 Antenna (Text-fig. 339) with flagellum only moderately clavate (the clava 

 about 1-5 times as broad as the first funicular segment) its segments sepa- 

 rated by deep constrictions ; area of micropilosity on the clava occupying 

 only half or barely half its length ; first funicular segment varying from 

 quadrate to 1 -5 times as long as broad, at most barely as long as the pedi- 

 cellus. Smaller species, length 2-05 to 2-9 mm. Basal cell of fore wing 

 with only a few hairs in its upper distal corner . obscura Walker (p. 466) 



(Males) 

 1 Antenna (Text-fig. 342) with funicle with only six segments separated by 



