PHASMIDjE. 
239 
inserted before the eyes, seldom of great length, 
and the joints elongated. The tegmina are often 
wanting : when they exist they are short and narrow, 
never covering the hinder wings ; the latter are often 
large, and not unfrequcntly ornamented with bright 
colours, a circumstance which generally takes place 
when the wings are not destined to be covered by a 
sheath. The pro thorax is short, the body very long 
and linear. 
These insects live exclusively on vegetable food. 
Their mandibles accordingly are of a different form 
from those of the mantid®, and better adapted for 
gnawing. Like grasshoppers and locusts they lay 
their eggs in the earth, and for this purpose the 
females are provided with a small ensiform ovipositor 
.n the extremity of the abdomen, covered by three 
leaflets when unemployed. The eggs of some of 
the species are of considerable size, certainly among 
the largest to be found in this class of animals. 
Those of Pkasma dilatatum are of a slightly oblong 
shape, flattened on one end. They are of a brown 
colour and marked all over with numerous impressed 
points, and have on one side a mark or double 
waved line so disposed as to represent a kind of 
cross. The flattened end is surrounded by a small 
rim or ledge, and seems to be the part which opens 
for the exclusion of the larva, since it readily separ- 
ates from the rest.* 
If not the most bulky of insects, some of the 
* Linn. Trans, iv. pi. 18. fig. 4, 5. 
