76 THE ENTOMOLOGIST. 



A. fiavipcs, though A . deniiculata and nigriceps were found (accord- 

 ing to the above-mentioned list), and tridentata also occurs. In 

 his Norfolk list Bridgman states that the Nomada is generally 

 rare in the Norwich district, but was common one season. A. 

 nigriceps he found commonly, and tridentata rarely on flowers 

 of Senecio, which on the whole appears to be the favourite 

 plant of the parasite. Andrenaflavipes he records on a single 

 specimen given to him by a friend ! Hallett, who has collected 

 assiduously and widely in Glamorgan, informs me that he has 

 not yet obtained A. flaripes in the county, but has found the 

 No7nada on Knantia in comr>SLny vfith A. marginata, A. dcntieu- 

 lata occurring in the same locality at the same time. F. Smith 

 himself records N. flavopicta in numbers near Deal, and A. 

 nigriceps and similUma from the same locality at the same time, 

 but he makes no mention of A. fiavipcs. Again, in the ' Ento- 

 mologist's Annual" for 1870 and 1871, he gives the results of 

 about two months" collecting in the neighbourhood of Ilfracombe, 

 N. Devon, and lists the species observed by him. N. fiavopicta 

 was taken and also A. denticidata and ??if/n"c^;5S, the former being 

 common on the ragwort. N. fiavipcs was not found at all. The 

 Nomada was also taken on Lundy Island, and he suggests that 

 it was parasitic on Halictiis rubicundus ! Tlie only species of 

 Avdrena found was pubescens {fuscipo^) — wrongly listed by him 

 under Halictns — but either denticidata or nigriceps may easily 

 have been overlooked on his two brief excursions to the 

 island. Asfiavipes usually forms very strong colonies where it 

 occurs on the Devonshire coasts, its absence from the above lists 

 is very significant. As A.fiiscipes also belongs to the group of 

 nigricejjs, it is not impossible that N. flavopicta sometimes 

 attacks it, especially in view of the fact that I have positive 

 proof that N. rufipes (i^olidaginis), its common parasite, also 

 infests A. denticidata. 



The evidence is strongly in favour of A. denticidata as the 

 host of N. flavopicta, but that other members of the group of 

 nigriceps are also attacked seems fairly certain. 



Paignton, March 1st, 1919. 



NOTE ON SOME GENEEA OF NYSSONID^. 



By R. C. L. Pkbkins, M.A., D.Sc, F.E.S., etc. 



In his synopsis' of "British Heterogyna and Fossorial 

 Hymenoptera " (' Tr. Ent. Soc.,' 1880, p. 265, etc.). E. Saunders 

 kept the three genera Gorytes, Latr., Hoplims, Lep., and 

 Arpactus, Jur., distinct, considering the differences in neuration 

 a sufficient reason. In his ' Hymenoptera Aculeata of the 

 British Islands ' he follows Handlirsch in uniting all under one 



