2. (Zo["o]l.) Any species of {Erethizon} and related genera,
native of America. They are related to the true
porcupines, but have shorter spines, and are arboreal in
their habits. The Canada porcupine ({Erethizon dorsatus})
is a well known species.
{Porcupine ant-eater} (Zo["o]l.), the echidna.
{Porcupine crab} (Zo["o]l.), a large spiny Japanese crab
({Acantholithodes hystrix}).
{Porcupine disease} (Med.). See {Ichthyosis}.
{Porcupine fish} (Zo["o]l.), any plectognath fish having the
body covered with spines which become erect when the body
is inflated. See {Diodon}, and {Globefish}.
{Porcupine grass} (Bot.), a grass ({Stipa spartea}) with
grains bearing a stout twisted awn, which, by coiling and
uncoiling through changes in moisture, propels the
sharp-pointed and barbellate grain into the wool and flesh
of sheep. It is found from Illinois westward. See
Illustration in Appendix.
{Porcupine wood} (Bot.), the hard outer wood of the cocoa
palm; -- so called because, when cut horizontally, the
markings of the wood resemble the quills of a porcupine.