252 TRANSFORMATIONS OF INSECTS. 
are parasites of species of Osmza, and others of Azzthophora ; and 
these different insects have great resemblances to the kinds they 
rob. But there are certain peculiarities of structure which dis- 
tinguish all the parasites, for they invariably have simple hind 
legs and no masses of hair which enable them to collect pollen 
readily, for they are not destined to work, and therefore they 
are not supplied with the necessary implements. Their jaws and 
lip are very short, and they have no necessity to gorge themselves 
with honey, for they will never have to supply their young with 
it. The true Momadine are slender-shaped Hymenoptera, are 
almost smooth, and resemble little wasps on account of their 
black and brown colours variegated with yellow. One species 
(Prosopis signata) introduces its eggs into the nests of other solitary 
bees; and the Welectide, which are called Cuckoo Bees, and which 
have a large body not unlike that of the Azthophora, are the 
parasites of these last-mentioned insects. 
Everybody knows the Humble Bees, the large velvety Hy- 
menoptera, that hum about the garden and-make so much noise 
when they are caught ina room. They form colonies or societies, 
which commence, enlarge, and end like those of the wasps. A 
fertile female takes upon herself the duties of a worker early in 
the spring, after having passed a long hybernation, and lays the 
foundation of the future swarm. She soon finds herself sur- 
rounded by workers, which enlarge the nest. Thus one humble 
bee (Lombus muscorum) builds nests which are not very easily 
found, for the female establishes them in little cavities in the 
middle of fields, and takes care that they are in the immediate 
neighbourhood of plenty of flowering herbs. Mowers often cut 
into these nests, and if they are examined they will be found to 
be composed of a vaulted roof formed of pieces of moss cleverly 
entangled and fastened together. The opening of the nest, 
however, is from below. If the covering of moss be removed, a 
second will be noticed, but it is formed of a thick layer of greyish- 
yellow wax. The moss, although collected in considerable 
quantities, would permit water to enter into the nest during 
heavy rains, but the lower roof of wax keeps. everything beneath 
it water-tight. After having removed the waxy covering, the 
interior of the nest comes into view, and a mass of little round 
