We owe to an English naturalist, Newport, the knowledge of another curious fact relating to the laying of humble bees, which is the expedient the females and the males have recourse to for hastening the hatching of the eggs. They place themselves, like fowls sitting on their eggs, over the cocoons containing the pupæ almost hatched. By breathing quickly, these industrious insects raise the temperature of their bodies, and consequently that of the air in the cells. Thanks to this supplementary heat, the metamorphosis of the pupæ is much hastened. Newport, by slipping miniature thermometers between the cocoons of the nymphs and the sitting humble bees, ascertained that the temperature of the latter was about 34° C., whilst the temperature of the cocoons left to themselves was only 27° C.; that of the air in the rest of the nest being only from 21° to 24° C. After many hours of incubation, at the same time natural and artificial, in which Art and Nature are so closely allied, after the sitting insects have many times relieved one another, the young humble bees come out of their cells. They are at first soft, greyish, moist, and very susceptible to cold. But after a few hours they become stronger, and the yellow and black bands with which their abdomens are surrounded begin to be marked out. The spring laying produces exclusively workers. The greatest abundance of eggs are laid in August and September. The laying of the female eggs begins in July; that of the males follows soon after. Until autumn the humble bees are incessantly enlarging their nests, and multiplying their little pots of honey. Without accumulating a great stock of provisions, for which they have no occasion, they always keep in reserve a quantity of pollen and honey for their daily wants. The cells in which the honey is stored differ very much in shape. Some species of humble bees give them long and narrow necks; others, less _recherché_ in their style of construction, simply make cylindrical vases. There are among the humble bees races of artists and races of simple builders; the one construct with taste, the other only seek the useful. During the day the humble bees cull honey from the flowers. At night they enter their home; but a certain number take the liberty of sleeping out. Surprised by the arrival of night in the bottom of the calyx of a sweetly-scented flower, they philosophically determine to sleep in the open air, lying on this perfumed bed, with the heaven as their canopy.