12 [January, 



NOMADA BUCEPHALAE n.n. FOE N. LATERALIS Sm. (nbc Panz.), 



AND NOTES ON N. CONJUNGENS H.-Sch. 



BY R. C. L. PERKINS, M.A., D.Sc. 



After a careful study of Panzer's figures, I am satisfied that his 

 N. lateralis is quite distinct from the species called by the same name 

 in F. Smith's works, and in all probability it was the well-known 

 parasite of Andrena praecojc, which Kirby had previously described 

 as N. xanthosticta, and Smith subsequently as N. hridgmaniana. 

 N. lateralis Sm., which is a distinct species and not a variety of 

 N. rvficornis as E. Saunders supposed, may be called N. hucephalae 

 after its special host Andrena bucejjhala. 



Recently, through the kindness of Prof. E. B. Poulton, I have 

 been able to examine some of the more difficult species of British bees 

 in the Hope department of the Oxford Museum. In sorting out the 

 various forms mixed up under the names of N. ruficornis L., jiavo- 

 guttata K., and other species, I found a series of about a dozen 

 examples of N. conjungens, the females mostly placed under flavo- 

 guttata, but the three males under other names. I had previously 

 discovered this species amongst some unmounted insects in Devon- 

 shire, taken at the beginning of June, 1916, but not by myself. It is 

 probable, therefore, that this Nomada will be found in most localities 

 where Andrena proxiyna occurs regularly. 



I have also since examined the single male example in the British 

 Museum collection referred to by Mr. Morice (Ent. Mo. Mag., LII, 

 p. 227) which entirely agrees in all important points with the British 

 specimens at Oxford, these latter being from the Chitty collection. 



Mr. Morice has (I.e.) given the characters, which have been used 

 to distinguish the $ conjungens from that of Jlavoguttata. The 

 smaller average size of the latter is evident, when a series is compared, 

 but the form of the body seems to me to be the same in both species, 

 provided that the segments of the abdomen are in the same state of 

 extension or i-etraction. The real, and, so far as I can see, probably 

 the only certain difference between the females of the two species is 

 found in the clothing of the propodeum. In well preserved examples 

 of jlavoguttata the hairs form two dense and conspicuous snow-white 

 patches, an adornment readily visible to the naked eye, but in conjun- 

 gens the propodeum is sometimes nearly glabrous, even in fresh 

 examples ; or, if it bears numerous hairs, these are longer and less 

 conspicuous than in the common and allied species. As a rule the 



