CANCER. CRAB. 
Generic Character. 
Pedes octo (rarins sex aut 
decern) insuper manus 
dute chelatae. 
Oculi duo, distantes, pleris- 
que pedunculati, elon- 
gati, mobiles. 
Cauda articulata, inermis. 
Xhe* genus Cancer is distinguished not more 
by the singularly curious shape and appearance of 
the animals it contains, than by the vast variety 
of species into which it is divided ^ the number of 
which is so great that it is found necessary to sub- 
divide them into sections, according to their dif- 
ferent shape or general habit, in order that they 
may be the more readily investigated. Some are 
of a short, thick, and nearly orbicular form, and 
sometimes the transverse diameter of the body 
considerably exceeds the longitudinal : others are 
of a thin and long form: some are strongly muri- 
* This Introduction to the genus Cancer is, in great measure, 
repeated from what I have before written on the same subject in 
tlie Naturalist’s Miscellany. 
Legs eight, (sometimes six 
or ten) besides two chel- 
ated arms. 
Eyes two, distant, generally 
footstalked, elongated, 
moveable. 
Taf/ jointed, unarmed. 
