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Show 536 DR. J. S. BOWERBANK O N [June 20, tain to whom I am indebted for the specimens. It is probable that I received them among other specimens of siliceo-fibrous sponges from my late friend, Mr. Henry Deane ; and if so, its locality may be the same as that of D.virgultosa; and I have a strong suspicion that the remains of the sponge in course of description should be referred to that species. The skeleton-structure is identical with that from the solid stem of D. virgultosa, which may very probably have been the stem of a perfect specimen of D. favoides, presuming that sponge to have been cup-shaped and elevated on a pedestal. I have three fragments of D. favoides, apparently from the same individual, neither of which exceeds three lines in diameter; and they exhibit very faint traces of curvature ; so that if they have been portions of a cup-shaped sponge, it must have been of considerable size-and are probably portions of its distal margin, as the pieces all agree in their general character, and no indications of approximation to the base of the cup is apparent in either of them. In the specimen of D. virgultosa the fibres of the rete of the stalklike specimen are rather stouter than those in D. favoides; but in other respects there is a remarkably close similarity. If the former should hereafter prove to have been the stalk or pedestal of a cup of the latter species, this slight difference might naturally be expected to occur. Another strong indication of the close alliance of the two species exists in the peculiarities of their sarcode, which in both is extremely dark and opaque. In D. favoides it is very abundant; but a very small portion remains attached to the small fragment of D. virgultosa in m y possession. Under ail the circumstances of the case I have thought it advisable to designate them as separate species, until further information enables us to decide the question. FARREA INERMIS, Bowerbank. (Plate LVI. figs. 3, 4.) Sponge cup-shaped ? Dermal surfaces furnished with a quadrilateral, smooth, or rarely incipiently spinous siliceo-fibrous network, rarely armed at its angles externally with short, stout, imbricated, conical, spicular defences. Areas square or slightly oblong, regular ; sides of the areas very rarely armed with long and slender acutely conical spines. Fibres of the dermal rete cylindrical, nearly equable in diameter, canaliculated irregularly. Dermal membrane thin and pellucid, aspiculous. Internal skeleton-rete indistinct and very irregular ; fibres slender, occasionally slightly furnished with minute conical spines ; gemmules spherical, smooth, membranous, aspiculous, dense and opaque. Colour, in the dried state, dark amber. Hab. West Indies? (Captain Hunter). Examined in the dried state. I received the only specimen of this sponge that 1 have seen, from my late friend Mr. Henry Deane, among several other species of siliceo-fibrous sponges, without any special account of its locality |