278 MODERN CLASSIFICATION OF INSECTS. 
scrapings of the wood. The tunnel, except at its top and bottom, 
which are bent, runs ina straight direction, so that the insect hatched 
from the lowermost first deposited egg makes its way, in all proba- 
bility, through the bottom aperture without disturbing its brethren 
overhead. 
We are indebted to Réaumur (Mém. tom. vi. mém. iv.) for the his- 
tory of the carpenter bees, Xylocopa, a genus containing the largest 
species of the family, all of which are exotic, the species described 
by Mr. Kirby in his Monograph having evidently no claim to be re- 
garded as a native species. Their wings are often black, with a fine 
purple or violet gloss, and some of the species are richly coloured. 
The females of X.violacea, the species observed by Réaumur in France, 
appear in the spring, and select posts, palings, espaliers, &c., in gardens, 
in which they construct (fig. 91. 7. mandible of a Chinese species) 
their burrows, from twelve to fifteen inches in length, and rather more 
than half an inch in diameter; the top and bottom of the tunnel is 
curved, having a passage at each end. When completed, they de- 
posit an egg at the bottom, with a proper supply of pollen paste ; the 
whole is then covered with a layer of agglutinated sawdust, formed 
during the construction of the burrow: the layer thus formed serves 
not only as the roof of one cell, but as the floor of another which is 
placed immediately above it. ‘They thus proceed until about a dozen 
cells are formed. When the larve are full grown, they assume the 
pupa state, head downward, so as to allow the lowermost and oldest to 
make its way out of the bottom of the burrow as soon as it becomes 
winged, and which consequently takes place earlier than in those 
which occupy the upper cells. The late Rev. L. Guilding has pub- 
lished an interesting account of the habits of one of the West Indian 
species, Xyl. teredo, in the fourteenth volume of the Linnean Trans- 
actions, illustrated with numerous figures. 
The males of some of the large species (X. latipes, and several 
others undescribed) have the fore legs greatly dilated. 
The fifth and last subfamily of the Apide is the SocraLes of 
Latreille (or ApipEs). Here, dependent upon their social habits, we 
find each species composed of three kinds of individuals; viz. males, 
females, and neuters, or workers.* In addition to their gregarious 
* When we consider that in the community of the hive bee, consisting, for instance, 
of at least 2000 males, 50,000 workers, and 1 queen, a single individual of the female 
