way; others
were a little wilder.

The man who caught them asserted that very many are invariably
found blind. A specimen which I preserved in spirits was in this
state; Mr. Reid considers it to be the effect of inflammation in
the nictitating membrane. When the animal was alive I placed my
finger within half an inch of its head, and not the slightest
notice was taken: it made its way, however, about the room nearly
as well as the others. Considering the strictly subterranean habits
of the tucu-tuco, the blindness, though so common, cannot be a very
serious evil; yet it appears strange that any animal should possess
an organ frequently subject to be injured. Lamarck would have been
delighted with this fact, had he known it, when speculating
(probably with more truth than usual with him) on the
gradually-ACQUIRED blindness of the Aspalax, a Gnawer living under
ground, and of the Proteus, a reptile living in dark caverns filled
with water; in both of which animals the eye is in an almost
rudimentary state, and is covered by a tendinous membrane and skin.
(3/7. "Philosoph. Zoolog." tome 1 page 242.) In the common mole the
eye is extraordinarily small but perfect, though many anatomists
doubt whether it is connected with the true optic nerve; its vision
must certainly be imperfect, though probably useful to the animal
when it leaves its burrow. In the tucu-tuco, which I believe never
comes to the surface of the ground, the eye is rather larger, but
often rendered blind and useless, though without apparently causing
any inconvenience to the animal; no doubt Lamarck would have said
that the tucu-tuco is now passing into the state of the Aspalax and
Proteus.

Birds of many kinds are extremely abundant on the undulating grassy
plains around Maldonado. There are several species of a family
allied in structure and manners to our Starling: one of these
(Molothrus niger) is remarkable from its habits. Several may often
be seen standing together on the back of a cow or horse; and while
perched on a hedge, pluming themselves in the sun, they sometimes
attempt to sing, or rather to hiss; the noise being very peculiar,
resembling that of bubbles of air passing rapidly from a small
orifice under water, so as to produce an acute sound. According to
Azara, this bird, like the cuckoo, deposits its eggs in other
birds' nests. I was several times told by the country people that
there certainly is some bird having this habit; and my assis