248 BRITISH BEES. 



is very long, and the quantity of pollen required for the 

 nurture of the larva is evidently small, from its having 

 been observed that the store upon which the egg is de- 

 posited is semiliquid, thus preponderating in the admix- 

 ture of honey. 



That it has not been caught laden with pollen upon 

 its legs has no weight against the fact of its non-para- 

 sitism, for it is not always that the excursions of bees 

 are made for the purpose of collecting pollen. Honey 

 is as necessary to their economy and in this case per- 

 haps more so as pollen, and the only way to determine 

 the fact of its carrying pollen, corroboratively, would 

 be when knowing that one of these bees has visited a 

 bramble stick its presumptive nidus, to watch the 

 stick very patiently for the insect's return from every 

 journey until it came back laden; the presence of 

 pollen upon its legs would surely be indicated by the 

 difference of its colour from the ordinary dark hue of 

 the little labourer. 



We have already noticed bees with metallic hues 

 among the Halicti, and there are slight indications of it 

 in some of the Andrenas, for instance, in the A. cinerea 

 and the A. nigro-tenea, etc., but in none hitherto so 

 absolutely is it exhibited as in this genus. The preva- 

 lent colour of the bees, that is to say, the ground colour 

 of the integument, and not the fleeting one of the pu- 

 bescence, is black or brown, but here we have a positive 

 metallic tinge, which we shall again come across in 

 many shades and hues in the genus Osmia. 



A second species of the genus was brought from 

 Devonshire by Dr. Leach, and is in the collection of the 

 British Museum, but no other specimens of the same 

 species have since been found. 



