PTEROMALIDAE OF N.W. EUROPE 765 



slightly longer malar space and rather smaller eyes ; the median area of the propodeum is 

 rather less transverse, its median carina usually strong, rarely weak, and the plicae rather 

 sharper throughout ; the legs are on the average darker. 



o*. Differs from the $ as follows : 



Body green, blue-green or bronze-green ; antennae, and legs, not counting coxae, testaceous, 

 the pedicellus and flagellum sometimes brown, the femora occasionally brownish proximally. 

 Length 1-3-1-9 mm. Eyes slightly larger, separated by only 1-1-1-25 times their length ; 

 malar space 0-4-0-47 the length of an eye. Antennal scape slightly shorter than an eye, reach- 

 ing about to the level of the middle of the median ocellus ; combined length of pedicellus and 

 flagellum slightly less than breadth of head. Gaster subcircular ; shorter, but a little broader, 

 than the thorax. 



The male differs from that of exiguus in its straighter temples, slightly larger eyes 

 and shorter malar space, relatively larger first funicular segment, and rather greater 

 average size. It differs from that of hemipterus in its straighter temples, slightly 

 larger eyes and in being macropterous. 



Holotype $. England : Kent, Romney Marsh, reared iii.1920 " from nest of 

 Brown-tail Moth " [Euproctis phaeorrhoea (Don.) (= chrysorrhoea auctt. nee L.)], 

 {F. W. Theobald), in BM(NH). 



Paratypes. Same data as holotype 9, 2 <$, 3 $ ; Cambridgeshire, Cambridge, 

 2 (J, 2 $, from "hibernating nest of Euproctis chrysorrhoea" , presented by Agricultural 

 Research Council ; U.S.S.R., Voronezh, 1 <$, 1 $, 29. iv. 1927, from " Euproctis 

 chrysorrhoea " (also determined as nidulans), the foregoing paratypes in BM(NH). 



Germany : unlocalized, 1 <$, 1 <j>, from Forster coll., and determined by him as 

 " nidulans Foerst.", in Hope Department, University Museum, Oxford. 



The species mentioned in the North American literature under the names egregius, 

 nidulans, and hemipterus, and which was introduced into the U.S.A. from Europe 

 in 1905 to aid in the control of the brown-tail moth, Euproctis phaeorrhoea (Don.) 

 [= chrysorrhoea (L.)], appears to be the present one. It was identified as egregius 

 Forster on the basis of a specimen named by that author in Sichel's collection in 

 Paris (see Howard and Fiske, 191 1 : 69), but this was a misidentification. Later it 

 was misidentified as nidulans (Thomson) by Gahan (1914) and as hemipterus (Walker) 

 by Burks (in Krombein et al., 1958). It has been cited several times under one or 

 other of these three names ; for a comprehensive list of references see Peck (1963). 

 I have not seen any of the material mentioned in these references, but in view of the 

 fact that this was originally reared from the brown-tail moth, and that Proper's 

 figure (1931, fig. 1) of the female agrees very well with my European specimens of 

 peregrinus sp. n., I have no doubt that all are the same species. 



Europe, widely distributed ; Canada, U.S.A. (introduced). 



Biology. Most of the type-specimens of peregrinus sp. n. were reared from webs 

 formed by the hibernating larvae of the brown-tail moth, Euproctis chrysorrhoea (L.), 

 but more precise data is not available. Much information, however, has been 

 published on the Eupteromalus parasite of this moth introduced into North America, 

 which I have concluded above to be the same as peregrinus. Proper (1931) gave a 

 summary to that date of the history of its introduction and the known facts regarding 



