ROOM XIII.] NATURAL HISTORY. 77 
and long tongues, which they have the power of darting 
forward, like the Woodpeckers, with great force. They 
prey chiefly on insects, and one genus (the Spider-Eaters), 
almost exclusively on spiders. 
The Fissirostral Birds, or those which feed chiefly on 
the wing, have generally very short weak feet, and large 
gaping mouths; they live principally on insects, though a 
few of the larger kinds catch fish. Some have very short 
beaks, as the family of Swallows (Cases 33 and 34), with a 
close plumage, and extremely long wings, which enable them 
to fly with great rapidity; they are generally birds of 
passage, and often live in flocks, as the Swifts, which have 
all the toes in front; some have the end of the tail feather 
rigid like the Woodpeckers ; the Esculent Swallow forms a 
nest of sea-weed, which is used as food in China, and forms 
no unimportant article in the commerce of that country. 
The family of Goat-suckers (same Cases) are nocturnal 
birds, and have the soft downy plumage, and dingy colours 
of that tribe. They are generally solitary, living on moths, 
and laying their eggs on the ground without any nest. 
The Leona Goat-sucker, a species from Africa, is peculiar 
for having a very long feather arising from the middle of 
each of its wings. The New Holland and South Ame¬ 
rican Podargi, are much larger than any of the individuals 
belonging to the family of the true Goat-suckers. 
The family of Bee Eaters (same Cases), which are ge¬ 
nerally of a green colour, have long, slightly arched beaks, 
and long pointed wings; they associate in flocks, and fly like 
swallows, pursuing bees and wasps, which they prey on 
with impunity. They are only found in the Old world and 
Australia. The King-fishers (same Cases) are generally 
of a brilliant blue, or green colour : they live on fish, 
which they catch by diving. 
Cases 35—44 contain the Zygodactylous, or Climb¬ 
ing Birds. The Parrots (Cases 35—37) are known to 
every one by their domestic habits; they are characterised 
by their short, hard beak, which is surrounded at the base 
by a naked skin, like the Falcon’s; and they have a short 
tongue, which is usually fleshy, but in a few, as the Black 
Cockatoo, it is hard and tubular. They are a very numerous 
group, and have been divided into many genera; they live 
chiefly on fruit. 
