46 NATURAL HISTORY OF WASPS. 
an alternation of light and shade; the black polished 
band which underlies the preceding segment bemg 
followed by a lighter coloured band before the dis- 
tinctive marking begins. A central point and two 
lateral square cusps distinguish this species; the 
point shrinking, and the squares separating from the 
black band, in the succeeding rings. 
There is no difficulty, as has already been said, 
in distinguishing the queens of V. vulgaris and V. ger- 
manica from each other, but the males and workers 
are not always readily to be referred to their respec- 
tive species. The first segment of the abdomen in 
the worker of V. vulgaris displays only a very narrow 
black band on its dorsal aspect, and the central 
marking is diamond-shaped, with the lateral angles 
much elongated. In some workers of the two species 
the markings of this rmg are absolutely the same. 
The saddle-shaped marking, which begins in the 
second ring of the queen of V. vulgaris does not 
begin till the third rmg of the worker; and that 
which this worker usually bears in her second ring 
is very like the marking of the worker of V. germanica. 
The male would be still more difficult to distinguish 
did not the form of the sexual* organs supply an 
unerring differential character under the microscope. 
When V. vulgaris has her typical saddle-shaped mark 
on the third ring, and that on the second ring of 
V. germanica does not deviate far from the figure of 
a dome, there is no difficulty; but when the black 
central mark shrinks in the first- and spreads in the 
last-named species, and the lateral marks of V. vulgaris 
* Smith. ‘ Catalogue of British Hymenoptera,’ 1858. Vespide, 
Plate V, figs. 20, 21. 
