830 M. W. R. de V. GRAHAM 



known what happens to those imagines which emerge in June and July ; possibly 

 they have another host on which further generations develop. 



Note. Scymnophagus latithorax Risbec (1951 : 275-277, fig. 142), described from 

 Senegal, does not belong to that genus ; it is probably near Dinarmus Thomson. 



PACHYNEURON Walker 



Pachyneuron Walker, 1833 : 371, 380. Type-species : P. formosum Walker, by monotypy. 



Pachyneuron Walker ; Forster, 1856 : 52, 54. 



Pachyneuron Walker ; Thomson, 1878 : 18, 27. 



Pachyneuron Walker ; Ashmead, 1904 : 329. 



Pachyneuron Walker ; Schmiedeknecht, 1909 : 371, 372, 373. 



Serimus Brethes, 1913 : 90. Type-species : S. argentinus by monotypy. 



Pachyneuron Walker ; Szelenyi, 1942 : 93-105. 



Pachyneuron Walker ; Nikol'skaya, 1952 : 247. 



Pachyneuron Walker ; Delucchi, 19556 : 122-139. 



Atrichoptilus Delucchi, 19556 : 141. Type-species : Pachyneuron aeneum Masi, 1929, by 



original designation. 

 Pachyneuron Walker ; Peck, 1963 : 612-619. 

 Pachyneuron Walker ; Peck et al., 1964 : 39-40. 

 Pachyneuron Walker ; Boucek, 1965^ : 16-18. 



Serimus Brethes was synonymized with Pachyneuron by de Santis (1957 : 118) 

 after having examined the original material of its type-species. 



Boucek (1965^) placed Atrichoptilus Delucchi in synonymy with Pachyneuron, 

 pointing out that the characters used by Delucchi (1955) for separating the two are 

 too variable to be considered of generic value. This conclusion is accepted here. 



The Palaearctic species of Pachyneuron were revised by Szelenyi (1942) ; but he 

 did not see the types of most of the species and for this reason his revision is 

 unsatisfactory. The European species were revised by Delucchi (19556) who 

 placed their taxonomy on a much sounder basis. Since then, however, some 

 changes in the synonymy and nomenclature have been made. The earlier-described 

 species are now reasonably well understood, but some of those described more 

 recently need further study. In particular the North American species, of which 

 Peck (1963) lists 14, need to be compared with those from Europe ; possibly some 

 of the former will prove to be identical with European species. 



The identity of Ichneumon coccorum Linneaus (1758 : 567) is very doubtful and 

 has been the subject of some controversy ; the available evidence suggests that it 

 was not a Pachyneuron. It was transferred to that genus by Reinhard (1857 •' 77)- 

 The type or types of coccorum are not in the Linnean collection in London, and I 

 could not find any specimens that agreed with the description in the DeGeer collection 

 in Stockholm. The original description, of course, is very brief and conveys little ; 

 but Linnaeus cited a reference to the work by DeGeer, " De Geer ins. 1. t. 35. f. 17 ". 

 Plate 35, fig. 17 of this work represents an adult Hymenopteron which can hardly 

 be anything except a Chalcidoid ; the antennae are shown as having a scape, 

 pedicellus, four funicular segments, and a clava. Although one must not place too 

 much emphasis on a figure drawn at that period, it would seem to rule out any 



