students of Mollusca.

2. RADIATA.

The eastern seas are profusely stocked with radiated animals, but it is
to be regretted that they have as yet received but little attention from
English naturalists. Recently, however, Dr. Kelaart has devoted himself
to the investigation of some of the Singhalese species, and has
published his discoveries in the Journal of the Ceylon Branch of the
Asiatic Society for 1856-8. Our information respecting the radiata on
the confines of the island is, therefore, very scanty; with the
exception of the genera[1] examined by him. Hence the notice of this
extensive class of animals must be limited to indicating a few of those
which exhibit striking peculiarities, or which admit of the most common
observation.

[Footnote 1: Actinia, 9 sp.; Anthea, 4 sp.; Actinodendron, 3 sp.;
Dioscosoma, 1 sp.; Peechea, 1 sp.; Zoanthura, 1 sp.]

_Star Fish_.--Very large species of _Ophiuridae_ are to be met with at
Trincomalie, crawling busily about, and insinuating their long
serpentine arms into the irregularities and perforations in the rocks.
To these they attach themselves with such a firm grasp, especially when
they perceive that they have attracted attention, that it is almost
impossible to procure unmutilated specimens without previously depriving
them of life, or at least modifying their muscular tenacity. The upper
surface is of a dark purple colour, and coarsely spined; the arms of the
largest specimens are more than a foot in length, and very fragile.

The star fishes, with immovable rays[1], are by no means rare; many
kinds are brought up in the nets, or maybe extracted from the stomachs
of the larger market fish. One very large species[2], figured by
Joinville in the manuscript volume in the library at the India House, is
not uncommon; it has thick arms, from which and the disc numerous large
fleshy cirrhi of a bright crimson colour project downwards, giving the
creature a remarkable aspect. No description of it, so far as I am
aware, has appeared in any systematic work on zoology.

[Footnote 1: _Asterias_, Linn.]

[Footnote 2: _Pentaceros?_]

_Sea Slugs_.--There are a few species of _Holothuria_, of which the
trepang is the best known example. It is largely collected in the Gulf
of Manaar, and dried in the sun to prepare it for export to China. A
good description and figures of its varieties are still desiderata.

_Parasitic Worms_.--Of these entozoa, the _Filaria medinensis_, or