tifa 
INTRODUCTION. 
The Hymenoptera may be roughly divided into a stinging or 
aculeate group and a non- stinging or non-aculeate group. The 
first comprises ants, bees and wasps, and here the sting (modi- 
fied egg-laying apparatus or ovipositor) issues from the tip or 
apex of the abdomen, while the trochanters of the legs are gen- 
erally simple; the second division includes leaf wasps, chalcis 
wasps, ichneumon wasps, etc., these having the ovipositor issuing 
(having its external origin) from before the end of the body, 
and the trochanters more often two-jointed. 
Ants practically always live in communities commonly made 
up of males, functional females or queens, and more or less 
sterile females or workers. All these phases have one or two 
node-like joints on the base of the abdomen. Bees as a rule are 
more hairy than wasps, though many of the parasitic groups are 
comparatively naked. At least, some of their hairs are branched. 
They feed their young with flower products, while most wasps 
provide theirs with animal food, usually insects and_ spiders, 
entire, in chunks, or well masticated. 
Social wasps, the “Yellow Jacket” (Vespa), for example, live 
in communities. As in the ants and social bees, the most spe- 
cialized kinds have three forms of individuals to a nest. These 
work for the good of the community. With the solitary wasps 
there are only males and functional females. Each of the latter 
provides solely for her own young, and even when living in dense 
colonies, as in certain sand-nesting forms (Bembex) and mud- 
daubers (Sceliphron), exhibit no cooperation. 
Nests oF WASPS. 
Since in their immature stages wasps are helpless creatures, it 
devolves upon the mother to provide them with food and shelter. 
This brings us to the subject of nests. Properly speaking, 
wasps of the most primitive type make no nests, but sting and 
parasitize their prey where they find them, and as these usually 
live in places well concealed from other enemies, the wasp’s 
brood 1s fairly secure. Thus here the victim’s abode substitutes 
in a way for the wasp’s inability to make a nest. The Bethylidae, 
usually small black wasps, often classed with the parasitic 
Hymenoptera, but more properly associated with the Aculeata, 
illustrate this point. Many prey on lepidopterous larvae, w hich 
they attack either in their retreat—as borings in decayed wood, 
or in rolled- up leaves—or in their cocoons (Sclerodermus, Sierola 
and Holepyris). The Hawaiian Sclerodermus tmmigrans Brid- 

