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Show 278 DR. J. S. BOWERBANK ON [^Pr- °> ton of the Farrea. The other groups consisted of two small densely compacted masses of very minute cylindro-stellate spicula with acutely conical radii: one of these groups just filled a skeleton-area; the other, of a similar size, was not entangled in the skeleton-structure, but adherent to it externally ; and within the little mass were a few spiculated biternate spicula, like those found in Farrea occa, figured in vol. i. plate ix. fig. 199, 'Monograph of British Spon-giadse.' A few minute anchorate spicula of different forms were also observed among the skeleton-fibres. These occurrences would seem to indicate that the locality whence this sponge was obtained would be a very prolific ground for scientific dredging. I received this sponge from m y late friend Mr. H . Deane, with the specimens of Farrea gassioti and pocillum ; and I therefore presume it is from a West-Indian locality. FARREA LCEVIS, Bowerbank. Sponge-mass unknown. Dermis furnished with a quadrilateral siliceo-fibrous network. Rete armed at the angles oppositely externally and internally with smooth elongate-conical attenuated spicular defences. Fibre smooth and spineless ; central canals large and very distinct, confluent at the angles, frequently two, rarely three, in each fibre. Dermal membrame thin, aspiculous. Sarcode amber-brown. Colour, in the dried state, brown ? Hab. West-Indian seas ? Examined in the dried state. I am indebted to m y friend Mr. Henry Lee for m y knowledge of this species. He found it on some sand dredged up by Mr. Marshall Hall during his voyage in the ' Noma.' The sand was preserved by Mr. W . Saville Kent, and was presented by him to my friend. Mr. Lee sent m e the specimen for examination. It is a fragment of a very fragile tubular sponge, which consists of only one layer of siliceo-fibrous tissue. It is five lines in length, and does not exceed three lines in diameter. The form of the fibres and their mode of arrangement very closely resemble those of the dermal tissue of Farrea occa; but they differ from those of that species in being smooth and quite destitute of spines, and also in being furnished abundantly with central canals. The conical spicular external defences at the angles of the rete differ also from those of F. occa, as, instead of being imbricated as in that species, they are quite smooth and each is furnished with a well-developed central canal. The canals in the fibres of tbe rete form a very prominent feature in this sponge; they are large and well developed, and are confluent at the angles of the network. There are frequently two in each fibre, one appearing to emanate at each end ; when they meet they do not unite, but run parallel to each other to their opposite angles. The dermal membrane is preserved in a few of the areas of the network. It is thin and transparent, and is well coated with sarcode, but I could not detect a single spiculum in any part of it. The |