th life,
the attractions are so numerous, that he is scarcely able to walk
at all.

The few observations which I was enabled to make were almost
exclusively confined to the invertebrate animals. The existence of
a division of the genus Planaria, which inhabits the dry land,
interested me much. These animals are of so simple a structure,
that Cuvier has arranged them with the intestinal worms, though
never found within the bodies of other animals. Numerous species
inhabit both salt and fresh water; but those to which I allude were
found, even in the drier parts of the forest, beneath logs of
rotten wood, on which I believe they feed. In general form they
resemble little slugs, but are very much narrower in proportion,
and several of the species are beautifully coloured with
longitudinal stripes. Their structure is very simple: near the
middle of the under or crawling surface there are two small
transverse slits, from the anterior one of which a funnel-shaped
and highly irritable mouth can be protruded. For some time after
the rest of the animal was completely dead from the effects of salt
water or any other cause, this organ still retained its vitality.

I found no less than twelve different species of terrestrial
Planariae in different parts of the southern hemisphere. (2/3. I
have described and named these species in the "Annals of Natural
History" volume 14 page 241.) Some specimens which I obtained at
Van Dieman's Land, I kept alive for nearly two months, feeding them
on rotten wood. Having cut one of them transversely into two nearly
equal parts, in the course of a fortnight both had the shape of
perfect animals. I had, however, so divided the body, that one of
the halves contained both the inferior orifices, and the other, in
consequence, none. In the course of twenty-five days from the
operation, the more perfect half could not have been distinguished
from any other specimen. The other had increased much in size; and
towards its posterior end, a clear space was formed in the
parenchymatous mass, in which a rudimentary cup-shaped mouth could
clearly be distinguished; on the under surface, however, no
corresponding slit was yet open. If the increased heat of the
weather, as we approached the equator, had not destroyed all the
individuals, there can be no doubt that this last step would have
completed its structure. Although so well known an experiment, it
was interesting to watch the gradual production of every