Genus SPONGIA.

S. pulchella, Sow.

Carrickfergus, Mr. Templeton.

S. limbata, Mont.

Specimens from Bangor, 1835, Dalkey Sound, 1836, Dr. Ball, Springvale, Down, have been so named by Dr. Johnston.

Grows about roots of tangle, as well as stones, &c.

G. compressa, Fabr.

Genus GRANTIA.

Strangford, W. T.

On the stems of various species of Algae, Corallina officinalis, and Zoophytes, on Antrim and Down coasts, and generally distributed.

G. lacunosa, Bean.

Strangford Lough, near Portaferry, July, 1838, W. T.

Dredged from a depth of 8 to 10 fathoms at Donaghadee, May, 1843, Dr. Drummond.

G. ciliata, Fabr.

This very beautiful species I have commonly found on marine plants on the North-East coast, and occasionally of large size. Specimens attached to a small Mytilus from Belfast Bay, December, 1844. On various Algae and Zoophytes, Down and Antrim coasts, Killery Bay, 1840, W. T. Two small specimens (4 inch in height) of this sponge were found attached to the carapace of a living spider crab (Stenorhyncus phalangium) dredged in Belfast Bay. This species is generally distributed on the Irish coasts.

G. botryoides, Ellis and Solander.

On various Algae and Zoophytes on Down and Antrim coasts; Strangford Lough, W. T. See remark on this, G. compressa, and G. ciliata, under Hal. incrustans; but they are found in rather deep water, as well as between tide-marks. Killery Bay, 1840, W. T.

G. fistulosa, Johnst.

Portaferry, W. T.

G. nivea, Grant.

West of Ireland, Mr. M'Calla.

G. coriacea, Mont.,

Was found on an Anomia attached to an oyster dredged at Killough, Downshire, March, 1835, W. T.

D. fragilis, Mont.,

Genus DYSIDEA.

Belfast Bay, Mr. Templeton. On tangle-root, Bangor, 1835, W. T. Dredged in Belfast Bay, August, 1840, Mr. Hyndman. Lough, from 20 fathoms, June, 1846, G. C. H. and W. T.

Strangford

APPENDIX.

I. SYNONYMS OF MOLLUSCA.

IN consequence of the great change that has taken place in the nomenclature of this class, the names used by Mr. Thompson are, in many cases, different from those of Forbes and Hanley, the latest authorities on the subject. It has therefore been considered desirable to enumerate all such species, giving in one column the name employed by Mr. Thompson, and opposite to it in another column, the corresponding term of Forbes and Hanley.

LAMELLIBRANCHIATA.