666 M. W. R. de V. GRAHAM 



genae, smaller and anelliform third flagellar segment, rather longer and more 

 strongly sculptured median area of propodeum, and stronger and coarser sculpture 

 of the mesoscutum. It also differs from jucundus in having the anterior margin of 

 the clypeus shallowly, instead of deeply, emarginate. 



A male specimen swept from Salix purpurea in the type-locality on 1g.vi.1961, 

 very probably belongs to this species, but I prefer to await confirmatory evidence. 

 It is a very handsome insect, resembling fasciiventris in general facies and having 

 the maxillary palpi modified as in that species ; but it differs in having the mid 

 tibiae simple ; the antennal scape longer than an eye ; broadest below the middle 

 and narrowing upwards ; the flagellum strongly clavate but proximally very slender, 

 much less stout than the pedicellus ; only the first flagellar segment small and 

 transverse, the second segment being slightly longer than broad and only slightly 

 shorter than the third, thus the funicle is almost 7-segmented ; the last segment 

 of the funicle, and the clava, are marked with blue-black. 



Mesopolobus fasciiventris Westwood 

 (Text-fig. 537) 



Mesopolobus fasciiventris Westwood, 1833a : 443,0*. 

 Eutelus fulvicornis Walker, 1834 : 363, $. 

 Eutelus flavipes Walker, 1834 : 364, $. 

 Ptevomalus fasciculatus Forster, 1841 : 11, <$. 

 Pteromalus Saxesenii Ratzeburg, 1844a : 203, $. 



Mesopolobus fasciiventris Westwood 

 Mesopolobus fasciiventris Westwood 

 Mesopolobus fasciiventris Westwood 

 Mesopolobus fasciiventris Westwood 



Graham, 19570" : 220-221. 

 v. Rosen, 1958 : 208-210, o* ?• 

 v. Rosen, i960 : 1-7, <$ $. 

 v. Rosen, 1960a : 24-25, o* ?■ 



Type material. For most of the above synonymy, and designation of lectotypes, 

 see Graham (1957a* : 220-221). In the above paper (p. 221) I cited Eutelus flavipes 

 Walker as a possible synonym of Mesopolobus jucundus (Walker) but mentioned 

 that none of the specimens in Walker's collection agreed with the description of 

 flavipes. Later von Rosen (1959a : 150) found a Walker female in the collections 

 of the Museum Nationale d'Histoire Naturelle, Paris, and designated it as type of 

 flavipes. 



Pteromalus saxesenii Ratzeburg. Original material presumed lost. Placed in 

 synonymy with fasciiventris, and a neotype designated, by von Rosen (1960a : 48). 

 Ratzeburg's species was wrongly interpreted by Thomson (1878 : 126) ; see note 

 below, under Eumacepolus grahami. The neotype of saxesenii is a female in the 

 Saxesen collection, Forstzoologischer Institute, Hannover, Miinden, Germany. 



Widely distributed (probably the whole of Europe). 



Biology. Reared from many different Cynipid galls, see references in von Rosen, 

 1958 : 212 ; also Askew, 19616 : 163-165 for host-list and detailed biological 

 observations. The species attacks either the larvae or pupae of Cynipids, or those 

 of other Chalcidoidea occurring in their galls ; according to Askew (1961& : 172) it 

 shows a preference for small leaf-galls. Bivoltine ; adults (in Britain) April-Nov. 



