TROPICAL AMERICA.—INSECTS. 85 
may be briefly noticed.—The land crabs are numerous, 
and very curious ; since they live but a part of the year 
in water, and resort, at other times, to the woods and 
forests. They seem to abound more particularly in the 
West India islands ; but whether they are of the same 
species as those found in Western Africa has not, we 
believe, been clearly ascertained. Many of the fresh- 
water crawfish are nearly as big as young lobsters. The 
scorpions are small, and, excepting those of Surinam, 
not much larger than the species found in the south of 
Europe. The venomous centipedes of Africa and Asia 
are strangers to this continent, or, at least, are so rare 
that we never met with one. The bird-catching spider 
Mygale avicularia (fig 35.), as it is improperly called, 
is the largest of this family yet discovered. Madame 
Merian, in her Surinam plates of insects, represents it as 
feeding upon the humming-bird ; but we never found 
it on trees, and suspect this habit is entirely contrary to 
its nature. The silkworm is unknown, either wild or 
cultivated ; but America possesses the cochineal insect, 
of nearly as much importance to commerce ; it has been 
hitherto confined to the republic of Mexico; and, be- 
sides its use in dyeing, furnishes the rich colour called 
carmine, the most beautiful of all the pictorial reds. 
(121.) To enumerate the tribes of winged insects 
peculiar to South America is altogether impossible ; 
yet we cannot pass over this lovely portion of creation 
a 3 
