e largest and most
interesting of the kind ever brought to this country.

When it is stated that seventy-eight of the species are new or
undescribed, the number will appear extraordinarily great, but when the
comparatively neglected state of exotic Zoophytology is considered the
wonder will be much diminished, and still further, as it may safely be
assumed, that many of the species here given as new have been previously
noticed, though so insufficiently described, as in the absence of figures
not to admit of correct identification.

Making, however, a considerable deduction on this account, the remainder
will still stamp the present collection with extreme value. As an
instance, may be cited the genus Catenicella, of which this collection
affords about fifteen species, and of which certainly not more than three
have been previously noticed in any way, and of these no sufficient
descriptions or figures are extant by which even that small number could
be identified. The explanation of this is perhaps to be sought in the
circumstance that the species of Catenicella are deepsea forms, and only
to be obtained by dredging in deep water--very few being apparently found
on the shores.

Though the number of new or supposed new species is so great, the number
of new genera is comparatively small, not amounting to more than four. It
has, however, been found necessary considerably to modify the characters
of several other established genera, so as to include new species.

With respect to the geographical distribution of the species, my means of
comparison have been pretty extensive. They have been derived from the
examination of Mr. Darwin's and Dr. Hooker's collections, placed at my
disposal by the kind liberality of Mr. Darwin--a considerable collection
of South African species mainly procured from Mr. Bowerbank--and from the
Collection of British and exotic Zoophytes in the British Museum, for the
freest opportunities of examining which I have to thank Mr. Gray. From
these various sources, and others of less account, I have been able to
examine species from a very considerable extent of the earth's
surface--more especially in the Southern hemisphere, and to arrive
perhaps at as fair a view of the geographical distribution of species as
the present imperfect state of Zoophytology will allow.

...

POLYZOA.

The number of species of Polyzoa is about fifty-four--belonging to
twenty-four genera. Of these genera it is belie