690 Insects. 



Mr. Kirby found M. ligniseca burrowing into an old putrescent elm ; 

 and he informs us it had constructed its nest in the heart of the tree, 

 which was beginning to decay : but he makes no mention of the chan- 

 nel being continued further. I have bred various species of these 

 bees, but have not yet met with one which burrows through the sub- 

 stance, in order that the lower bee may escape first. I have invaria- 

 bly found that the males are the first to arrive at maturity, and that 

 they invariably occupy the upper cells. An accurate observer, under 

 the name of Delta, has detailed a contrary mode of development in 

 the instance of Chelostoma maxillosa, in the 1st vol. of the ' Entomo- 

 logical Magazine.' 



The leaf-cutter bees are subject to the intrusion of parasites, be- 

 longing to the genus Ccelioxys. I have frequently observed Coelioxys 

 conica entering the burrows of Megachile circumcincta; and Mr. Wa- 

 terhouse has bred this parasite from the cocoons of that species, as 

 detailed in the ' Entomological Magazine,' iii. 498. In the summer 

 of 1842, being on an entomological excursion in Hampshire, I ob- 

 served a bee enter an old post, bearing a piece of leaf; and immedi- 

 ately afterwards, a Coelioxys settled on the post, within a few inches 

 of the burrow. She at last approached, but on reaching the entrance 

 she stopped short, as if aware of the presence of the owner, and was 

 about to fly off, when I captured her, and it proved a specimen of C. 

 Vectis, figured by Mr. Curtis in his beautiful work on British Ento- 

 mology. I afterwards caught the leaf-cutter, which proved to be the 

 Megachile maritima of Kirby. Both these species are common in 

 the Isle of Wight. 



The females of this genus offer no very striking differences for spe- 

 cific distinction, their resemblance to each other being remarkable ; 

 but the males offer striking differences of form, and are easily distin- 

 guished. I shall be able to add three species to those described by 

 Mr. Kirby, and to describe the males of two others, the females only 

 of which were known to that eminent author. It will be necessary to 

 bear in mind that all my descriptions are drawn up from recently de- 

 veloped specimens ; for in these insects the pubescence soon changes 

 colour, from exposure even to light, the beautiful light brown or yel- 

 low becoming more or less grey or ashy, according to the age of the 

 insect. 



