BEES OF GREAT BRITAIN. 65 



The female of this species is the most beautiful in the genus,, 

 and is a most abundant insect ; usually appearing with the apple 

 blossoms, to which it delights to resort ; it is particularly abun- 

 dant on Hampstead Heath, where in 1840 I captured several 

 pairs in coitu ; since which time I have on more than one occa- 

 sion detected them in company. The male is so unlike the 

 female, that nothing short of such an observation, except find- 

 ing them in their burrows, could lead any one to suppose that 

 they belonged to the same species. The best time for making 

 such observations appears to be between nine and eleven on fine 

 quiet sunny mornings. The beautiful colouring of "fulva " soon 

 fades by exposure to the sun ; it is therefore necessary to watch 

 for their first appearance : the female fades to a pale yellow, and 

 is subject to have the pubescence rubbed off ; whilst the male 

 becomes entirely of a hoary grey. No examples of this species 

 have been received from Scotland, but it will probably be found 

 there, as it is met with both in Denmark and Sweden. 



17. Andrena Clarkella. 

 ^4.atra, hirsuta; thorace pedibusque posticis fulvis. 



Melitta Clarkella, Kirly, Mon. Ap. Angl. iL 130. 69 ? . 



Andrena dispar, Zett. Ins. Lapp. 460. 2. 



Andrena bicolor, St. Farg. Hym. ii. 243. 12 (nee Fabr.). 



Lucas, Explo. Sc. Alger. iii. 180. 82 ? 

 Andrena Clarkella, Smith, Zool v. 1747. 36 $ ? . 



Nyland. Ap. Boreal p. 212. 7 ? . 



Female. Length 5-6^ lines. Black ; the pubescence black, 

 excepting that on the disk of the thorax, posterior tibise and 

 tarsi, and a little at the base of the abdomen, which is fulvous ; 

 the wings subhyaline, their apical margins slightly clouded, 

 the nervures ferruginous ; the posterior tibiae and tarsi fulvo- 

 piceous; the intermediate tarsi fulvous beneath. Abdomen 

 ovate, entirely black. B.M. 



Var. a. The two basal segments fringed with fulvous pubes- 

 cence. 



Var. /3. All the abdominal segments fringed with fulvous pubes- 

 cence. 



Male. Length 4^-5 lines. Black ; the pubescence on the 

 clypeus pale fulvous, above which, as well as along the sides of 

 the face, it is black ; the disk of the thorax clothed with fulvo- 

 ochraceous pubescence ; on the metathorax and beneath it is 

 pale fulvous ; the wings hyaline, iridescent and faintly clouded 



