48 
SYSTEM OF NATURE. 
the ant-eater and Echidna; it has .the same slenderness ; 
the same extraordinary extensibility; the same viscid co¬ 
vering ; and is always employed for the same purpose. 
Again, the wryneck (Yunx Torquilla) “ is a feathered ant- 
eater, and is organized by its Creator to entrap its prey 
by the very same means as the quadruped ones. Like 
them, it can protrude its tongue to a very great lengthy 
which is not owing to the structure of this organ itself, but 
to a peculiar ligamentous sheath in which it usually is 
contained. Its salivary glands are above an inch long, 
and shaped somewhat like a tea-spoon. The saliva they 
secrete is so very viscid as to be capable of being drawn 
into threads finer than a hairy and several feet in length ; 
so that, when the tongue is besmeared with it, no insect 
that touches it can escape. Like its analogues, it darts 
its tongue into an ant-hill, or lays it on an ant-track, and 
draws it back into its mouth laden with prey The 
woodpeckers are, therefore, ant-eaters among birds : they 
are preeminently creeping birds. 
Gthly. Tlte Ambulantia. The llama, the camel, the 
giraffe, the horse, the ox, are the largest of their kind: 
they are strong and stout, and are remarkable for length 
of leg: while the cats and moles, and rats and mice go 
with their bellies touching the ground, these huge crea¬ 
tures walk as it were on stilts: they feed exclusively on 
vegetables, sometimes on the seed, sometimes on the 
wood, but mostly on the leaf or herbage. The mouse 
and the sparrow are the unwelcome and furtive attend¬ 
ants on man : these are his welcome and cherished 
dependants. Among birds, those tribes whence spring 
* Kirby’s Bridgw. Treat, ii. 464. 
