66 



BEES OF GREAT BRITAIN. 



at their apical margins, the nervures pale ferruginous ; the legs 

 have a pale fulvous pubescence ; the apex of the posterior tibiae 

 more or less pale testaceous within. Abdomen ovate-lanceo- 

 late, shining, and thinly clothed with long pale fulvo-ochraceous 

 pubescence, the extreme apex pale testaceous. B.M. 



In the Catalogue of British Hymenoptera, the name " bi- 

 color " of Fabricius was adopted for this species, St. Fargeau and 

 Lucas having done so ; but I feel great pleasure in being able 

 to retain that of Clarkella, particularly as Mr. Kirby named it 

 in honour of Mr. Bracy Clark. Dr. Nylander having seen a 

 typical specimen of the A. bicolor of Fabricius in Sehestedt's 

 Museum, states that it is the insect named A. (Estiva, and which 

 Mr. Kirby had included in M. Gwynana, probably considering it 

 a mere variety. On referring to the first description of A. bicolor 

 in the ' Systema Entomologiae/ we find that Fabricius says, 

 " affinis et succinctce, at abdomen immaculatum ; " in all his 

 subsequent works, the ' Entomologia Systematica ' excepted, he 

 has omitted this observation ; from which it appears that A. 

 Clarkella has no relation to the species described as A. bicolor. 

 But Dr. Nylander has set the matter at rest. 



No bee is known which has a wider geographical range than 

 A. Clarkella ; it is found in all parts of the United Kingdom, 

 apparently preferring elevated situations; it occurs in France, 

 Germany, Lapland, Finland, Denmark and Sweden ; it has also 

 been found in Algeria, and there is a series of specimens in the 

 British Museum from Nova Scotia. 



This bee is usually the first which appears in spring ; as early 

 as the 4th of March in 1849, but the weather that season was 

 unusually mild ; the general time for its appearance is about the 

 third week of March. I have frequently dug both sexes out of 

 the same burrow, and have more than once observed the sexes 

 in coitu, first in 1840. Males are sometimes captured in spring 

 before the snow has quite disappeared. 



The female is subject to vary : the second variety is the colour 

 of most of the specimens from Nova Scotia, and appears to be 

 the common northern form of the species. 



All the specimens received from Scotland belong to this latter 

 variety. 



