BEES OF GREAT BRITAIN. 209 



females of different species of Bombi ; and in May, when the 

 horse-chestnut blooms, from the break to the close of day the 

 hum of these industrious bees is unceasing. 



Great difficulty has hitherto attended the discrimination of 

 the species ; no examination of specimens, or comparisons, could 

 ever produce a correct division of these insects ; in the pages 

 open to all, in the woods, in the fields, and on the hills alone, 

 could this be attained. During my entomological rambles for 

 twenty years, no opportunity has been lost of acquiring a correct 

 knowledge of these bees ; and by an examination of an immense 

 number of nests, and collecting the varieties into which the 

 sexes run in many species, I hope to clear away many difficulties. 

 The greatest tendency to vary in colouring will be found to ob- 

 tain in the males, and no other method of correctly bringing 

 together the extraordinary varieties which occur in this sex in 

 some species has been discovered, than an examination of the 

 organs of generation ; in all the species they differ in form, 

 but are constant in each individual species. The numerous 

 varieties in the male sex of Bombus muscorwn can be correctly 

 and easily ascertained by the method which I have suggested ; 

 whilst in those species in which the other sexes differ in their 

 colouring, the correctness of the descriptions may be relied upon : 

 nearly all have been made from individuals either captured in or 

 bred from the nests. 



The economy of the Bombi has been very fully detailed by 

 numerous authors. M. P. Huber has paid great attention to the 

 economy of these bees, and his observations on their habits are 

 generally in accordance with my own. I never found any females 

 hybernating in the old nests ; at the end of autumn these are 

 always entirely deserted. During the winter months torpid 

 females may be found hybernating, always singly, in decayed 

 trunks of tree, under turf stacks, or in other sheltered and dry 

 situations. The females of these bees, having passed the winter 

 in a torpid state, are roused from their slumber by the warmth 

 of returning spring, and each becomes the foundress of a sepa- 

 rate colony. The nests formed in the first instance are of small 

 dimensions, just sufficient to contain a few cells, in which to rear 

 workers to assist her in the extensive works necessary to the 

 wants of a large colony. When the larvae of the bees are full- 

 grown they spin a tough oval cocoon of silk, in which they 

 assume the nymph state, and w r hen sufficiently advanced towards 

 maturity to require food, they commence gnawing off the top of 

 the cocoon, in which they are greatly assisted by the workers. 

 On first emerging from their confinement they are by no means 

 matured, the pubescence with which they are covered is almost 

 of one uniform pale colour, and it requires several days before 



