make large cavities in the pollen mass. When they have attained their full size, they spin a silken wall about them, which is strengthened by the old bees covering it with a thin layer of wax, which soon becomes hard and tough, thus forming a cell (Fig. 15, 1, cell containing a larva, on top of which (2) is a pollen mass containing three eggs). The larvæ now gradually attain the pupa stage, and remain inactive until their full development. They then cut their way out, and are ready to assume their duties as workers, small females, males or queens.

"It is apparent that the irregular disposition of the cells is due to their being constructed so peculiarly by the larvæ. After the first brood, composed of workers, has come forth, the queen bee devotes her time principally to her duties at home, the workers supplying the colony with honey and pollen. As the queen continues prolific, more workers are added, and the nest is rapidly enlarged.

"About the middle of summer, eggs are deposited, which produce both small females and males." ... "All eggs laid after the last of July produce the large females, or queens, and, the males being still in the nest, it is presumed that the queens are impregnated at this time, as on the approach of cold weather all except the queens, of which there are several in each nest, die."

16. Meloë.

While the Humble bee in some respects shows much less instinct than the solitary bees mentioned below, it stands higher in the series, however, from having workers, as well as males and females, who provide food for the young. The labors of the Mason bees, and their allies, terminate after the cell is once constructed and filled with pollen. The eggs are then left to hatch, and the young care for themselves, though the adult bee shows greater skill in architecture than the Humble bee. It is thus throughout nature. Many forms, comparatively low in the scale of life, astonish us with certain characters or traits, reminding us of beings much superior, physically and intellectually. The lower forms constantly reach up and in some way ally themselves with creatures far more highly organized. Thus the fish-like seal reminds us strikingly of the dog, both in the form of the head, in its docility and great intelligence when tamed, and even in its bark and the movements of the head.

The parasites of the Humble bee are numerous. Such are the species of Apathus, which so closely resembles the Humble bee itself, that it requires long study to distinguish it readily. Its habits are not known, other than that it is found in the nests of its host. It differs from the Humble bee in having no pollen-basket, showing that its larvæ must feed on the food stored up by their host, as it does not itself collect it. The mandibles also are not, like those of Bombus, trowel-shaped for architectural purposes, but acutely triangular, and are probably not used in building.

The caterpillars of various moths consume the honey and waxen cells; the two-winged flies, Volucella and Conops, and the larvæ of what is either an Anthomyia or Tachina-like fly, and several species of another genus of flies, Anthrax, together with several beetles, such as the Meloë (Fig. 16), Stylops (Fig. 17, male; 18b, female; a, position in the body of its host), and Antherophagus prey upon them.

17. Male Stylops.

The power of boring the most symmetrical tunnels in solid wood reaches its perfection in the large Virginian Carpenter bee (Xylocopa Virginica, Fig. 19). This bee is as large as, and some allied exotic species are often considerably larger than, the Humble bee, but not clothed with such dense hairs. We have received from Mr. James Angus, of West Farms, N. Y., a piece of trellis from a grape vine, made of pine wood, containing the cells and young in various stages of growth, together with the larvæ and chrysalids of Anthrax sinuosa (Fig. 20), a species of fly parasitic on the larva. The maggot buries its head in the soft body of the young bee and feeds on its juices.