quite
distinct from the European species, and scarcely less beautiful. It is
occasionally washed ashore in considerable numbers on the islands in
Bass' Strait. The beautiful _Janthina fragilis_ has been washed ashore
with its inhabitant on the east coast.

Although many forms are almost purely Australian, there are,
nevertheless, a great number of European types, such as species of
_Mytilus, Venus, Pecten, Ostrea, Patella_, &c.

The only kind of shell-fish commonly consumed as an article of food and
brought to market is a species of oyster. With the aborigines, however,
shell-fish formed a very considerable and important article of diet. La
Billardiere[274] describes their diving for _Haliotis_ at Recherche Bay;
and abundant remains of their feasts still exist all along the coasts,
and, in some places, many miles inland, the shell-fish having been
carried in baskets by the women, to situations where fresh water was to
be found. The sites of these aboriginal feasts are usually easily to be
distinguished from raised beaches, or those accumulations of shells
caused by change in the relative levels of sea and land. They may be
known by their isolated character and position; by their forming, in
many instances, round mound-like heaps, or tumuli; by the shells being
injured by fire, often broken into small pieces, intermixed with
fragments of charcoal; and from the fact of no small species of shell,
not likely to form an article of food, being found intermixed.[275] The
species of shell-fish consumed by the aborigines were numerous, and
varied according to the locality in which each shell abounded. Those
commonly used were the two species of _Haliotis_, _Mussels_, a _Turbo_,
and _Oyster_: several of the smaller _bivalves_ and _univalves_ were,
however, occasionally used, but it does not appear that the _aborigines_
of Tasmania ever eat the _Unio_, so far as can now be traced; in this
instance exhibiting a remarkable difference from those of New Holland,
with whom the _Unio_ forms an important article of diet.

The land shells are inconsiderable in number, not amounting to more than
about six species. The freshwater kinds, including those inhabiting
ditches, ponds, &c., are more numerous; but, except the _unio_, all are
small and insignificant. Some species occur abundantly in situations
which are perfectly dry for at least six months of the year, and seem,
like many snails, to have the power of sustaining life for a long p