228 
SYSTEMATIC ARRANGEMENT. 
for enabling them to secure their victims. One of 
the distinguishing marks of the present family is the 
great length and thickness of the forelegs, which, 
owing to the length of the thorax, usually appear 
remote from the other pairs, and placed near the 
head. They thus admit of being extended forwards 
considerable way from the body, and their struc- 
ture admirably adapts them for seizing small objects. 
The thigh, which is the thickest portion, is grooved 
on its inner edge, and beset with a double row of 
strong spines ; the tibia is so formed as to close 
upon it as the blade of a pocket-knife does upon its 
handle, and being likewise spinous on its interior 
edge, effectually secures any object that may be 
within, in a manner somewhat similar to what is 
practised by that carnivorous vegetable the Dionea 
muscipida. The efficiency of this implement is 
shewn not only in seizing small insects, which be- 
come an easy prey, but in the combats which the 
Mantidse carry on with each other, for a dexterous 
application of it decapitates an opponent as expe- 
ditiously as could be done by a guillotine. In a leg 
so constructed, the tarsus becomes a verj' subordin- 
ate appendage, being short and weak, and apparently 
unequal to support the body, resembling that part 
in certain Coleopterous genera (such as Phanceus , 
Geotrupes , &c.) where it shews a tendency to be- 
come obsolete, as its functions are performed by the 
extremity of the tibiae. These raptorial legs are 
often equal to the entire length of the body, and in 
some instances even surpass these dimensions. 
