GENERA OP ANDRENIDJE. l63 



America and Europe; but it is in the former that its 

 most eccentric species occur. The approximate genus 

 JVomia, which is also found throughout the world, ap- 

 pears to represent Hatictus in India, where possibly it 

 is of similar extent, if we may judge analogically from 

 the diversities of form that occur in the species we 

 have seen. This genus is distinguished by the usually 

 very enormously enlarged and curiously spined posterior 

 femora and tibise, and elongated tarsi of the males, and 

 the frequently very large tegulse of both sexes. A re- 

 markable species of this genus we are acquainted with 

 from the Cape, which has the anterior tarsi dilated like 

 the first section of Megachile. In this division we will 

 only further allude to the extremely elegant Dasypoda, 

 which derives its name from its densely hairy posterior 

 tibiae and tarsi, and which are furnished with an in- 

 creased facility for retaining the large masses of pollen 

 they enable the insect to convey, by each hair giving 

 off' on each side, throughout its whole length, other in- 

 numerable very short and slender hairs.* The re- 

 markable genus Macropis Klug (the Meg ilia labiata of 

 Fabricius) has recently been added to the British fauna ; 

 and we owe the possession of this unique insect to the 

 liberality of the captor, Mr. Walton, who took it in the 

 New Forest ; but we introduce the notice of it here, only 

 to observe that it distinctly points in many peculiarities 

 to the fourth division of the solitary bees (the Scopuli- 

 pedes). The typical genus Andrena is perhaps of still 

 greater extent than Halictus; but its range, both struc- 

 tural and geographical, is more confined, indeed, it rarely 

 presents abnormal species. It was upon one of this 

 genus (A. nigrocenea) that Mr. Kirby made the inter- 

 esting discovery of the very singular parasite Stylops, 



* Various kinds of this peculiar structure occur in different genera, and 

 none of which have before been noticed : it has also modifications which 

 accomplish the same purpose; thus, in Panurgus, instead of the hairs being 

 pilose, they are crenulated towards their extremity. That it only accom- 

 panies certain peculiarities of economy is proved by many of the very hairy- 

 legged divisions of the bees (the Scopulipedes) having these hairs entirely 

 simple. I am preparing a paper on the subject, in which all these peculi- 

 arities will be shown. W. E. Sh. 



M 2 



