118 BEES OF GREAT BRITAIN. 



found when the colony was first discovered : the cells of Eucera 

 were found at about the depth of eight inches in a stiff clayey 

 soil ; of these a considerable number were obtained : on exami- 

 nation, many of the bees were found to be in the pupa state, 

 some far advanced towards their perfect condition, others still 

 larva? ; on opening one cell, it was found to contain two speci- 

 mens of Nomada sexfasciata. Since the former visit I have on 

 several occasions obtained the cells of Eucera, and have endea- 

 voured to find the larva of Nomada, but in vain ; perfect indi- 

 viduals of N. sexfasciata have been found in the cells of Eucera 

 on several occasions, usually two in each cell, and once a pair of 

 N. alternata. 



Another circumstance connected with these parasites remains 

 to be noticed. Certain species appear to be constant in their 

 attacks on particular species of Andrena, others as constantly on 

 those of Halictus ; the species Nomada varia appears to confine 

 its attacks to the nests of Halictus abdominalis and H. rubi- 

 cundus ; N. solidaainis to that of H . leucozonius : A T . furva 

 enters the burrows of H. morio ; but I would by no means be 

 understood as stating these combinations to be undeviating ; it 

 will no doubt be found that many species attach themselves to 

 any bee which supplies a suitable provision for its larva. 



1. Nomada rnficornis. 



N. ferruginea ; thorace lineis tribus longitudinalibus atris ; ab- 

 denrine maculis fasciisque flavis. 



Apis ruficornis, Linn. Faun. Suec. 1707 ; Syst. Nat. i. 958. 34, ty* 

 Cab. Mus. Linn. Soc. ? . 



Kirby, Mon. Ap. Angl. ii. 210. 27. 



Nomada ruficornis, Fair. Syst. Ent. p. 389. 3 ; Ent. Syst. ii. 347. 7 ; 

 Syst. Piez. p. 509. 2. 



Rossi, Faun. Etrus. ii. 112. 933. 



Panz. Faun. Germ. 55. 18. 



Latr. Hist. Nat. xiv. 50. 1. 



Schaff. Germ. Zeits. i. 279. 9. 



St. Farg. Encycl. Meth. viii. 366. 7 $ ? ; Hym. ii. 498. 29. 



Blanch. Hist. Nat. Ins. iii. 411. 



Smith, Zool. ii. 596. 9. 



Nyland. Ap. Boreal, p. 180. 10. 

 Nomada flava, Panz. Faun. Germ. 55. 21 ^ . 



Fabr. Syst. Piez. p. 391.4. 



Lucas, Explor. Sc. Alger. iii. 221. 165. 



Nyland. Ap. Boreal p. 179. 8. 

 Apis flava, Kirby, Mon. Ap. Angl. ii. 186. 8 $ . 



