» 196 NATURAL HISTORY OF WASPS. 
appearance, is of great strength and well calculated 
to defend from injury the important connections which 
it maintains. Next to this follow the rmgs—six in the 
female and seven in the male—each representing a 
larval segment, which compose the tegumentary 
skeleton of the abdomen. The remaining larval 
segments, two or three, as the sex determines, are 
absorbed in the composition of the sting, saw, borer, or 
analogous organ with which Hymenopterous insects 
are provided. The larva in this Order has the excep- 
tional number of fourteen segments, but the supernu- 
merary segment, though it may enter into the com- 
position of the supernumerary organ in the perfect 
insect, is not to be regarded as its larval repre- 
sentative. | 
The abdomen is united to the thorax by strong 
ligaments, and besides these, there is a strong fibrous 
cord which, emerging through a notch in the post- 
scutellum of the meta-thorax, is inserted into the 
upper surface of the pedicle. The structure of this 
cord shows it to be, not an elastic ligament like that 
which supports the heavy heads of the Ruminantia on 
their long necks, but the tendon of a muscle contained 
within the thorax, by which the abdomen can be 
raised at the will of the insect. 
Kach of the abdominal rings is made in two pieces, 
a dorsal and a ventral scale. The dorsal overlap the 
ventral scales, and each ring is overlapped by that 
immediately preceding it to a variable extent. The 
apparent size of a wasp depends much on how far the 
abdominal rings are drawn in or out, and to obviate 
any uncertainty from this cause, the measures of its 
length are often calculated no farther than to the 
