CLASSIFICATION OF THE SPECIES. 35 
as briefly as may be consistent with practical use. 
And as we are anticipating their regular description, 
it may be necessary here to indicate what parts are 
meant by some of the different terms employed. 
It is scarcely necessary to explain what is meant 
by the rings of the abdomen, the thorax, or the 
antennee. But it is not as generally known, perhaps, 
that the scape of the antenna is the first joint, the 
handle, as it were, of the flail to which antenne of 
this form are familiarly compared. The corona and 
clypeus are parts known only to entomologists by 
these names; the corona is the little yellow spot 
between the roots of the antenne, and the clypeus 
is the broad yellow central patch which constitutes 
so large a portion of a wasp’s face. The large com- 
pound eyes are indented by a deep notch behind the 
antennee, dividing them into two portions which are 
technically called the upper and lower limbs. With 
this explanation, and by reference to the plates, there 
should be no difficulty im followimg the description 
of the several species. | 
Of these there are seven. V. crabro the great 
hornet stands alone. Three are tree-wasps, so-called 
from building by preference in trees or in the open 
air, namely, V. britannica, V. sylvestris, and the rare 
V. arborea. The three remaining species, which, as 
building by preference under ground, are called 
ground-wasps, are V. germanica, V. vulgaris, and 
V. rufa. Let us now proceed to examine each of 
these separately. } 
V. Crabro, Plate I, to commence with the hornet, 
differs from the rest in colour as well as size. The 
D 2 
