Now, let us see if we can make anything out of these front legs.
The coxa is small and close to the body.
The trochanter, II, is very large and long.
Yes, Charlie, it increases the size and strength of the leg very greatly, by being thus enlarged.
The femur, III, is large and strong, too, and it has a row of sharp, spiny teeth down the inside.
The tibia, IV, is also well supplied with cruel teeth, and at the end of it is the tarsus, as you see.
You know how the mantis uses these legs. The joint between the tibia and femur is a strong hinge joint. If can shut the tibia close to the femur, the spiny teeth of the one locking into the spiny teeth of the other, and forming a terrible trap for the insects that are so unfortunate as to get caught in its merciless grip.
Altogether, you see, it is quite a terrible leg, though it has no more segments than a common leg.
The segments are changed in shape and size from the regular leg segments.
When any part is changed from the regular shape or size, we say it is modified.