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Show 462 DR. J. s. B O W E R B A N K O N [June 5, spinous, very long and slender, and often flexuous, intermingled with single spicula of the same form and size irregularly dispersed. Interstitial spicula varying from cruciform to rectangulated sexradiate, radii cylindrical, incipiently spinous, numerous. Retentive spicula minute' sexradiate stellate, radii bi- or trifurcate, attenuated, immersed in the sarcode, very numerous. Colour, in the dried state, very pale grey. Hab. Cebu (Dr. A. B. Meyer). Examined in the dried state. Type in the Dresden Museum. If one adopts the rule that I have followed in all m y previous descriptions of sponges, that the structure and mode of arrangement of the materials composing the skeletons of the Spongiadae are the legitimate source of their generic characters, this sponge is decidedly a Hyalonema, but without the so-called glass rope. This organ in Hyalonema is not really a portion of the essential skeleton, but is rather an appendage thereto, and is apparently of the nature of a cloacal organ. Entertaining these views, I have, in accordance with them, referred the sponge in course of description to the genus Hyalonema; and from its discrepant structure I have given to it the specific name of H. anomalum. The interstitial spicula of both species also agree in being cruciform, with spinous cylindrical radii; and in each their forms are more or less variable in the number of the radii, and in both they are numerously dispersed amid the interstitial structures. This sponge is 3\ inches in height and 2 inches in width at its distal extremity. In its present state it is somewhat compressed. It has no part of its basal attachment remaining; and it was in this condition apparently when taken from the sea; and from the very small remains of sarcode amid the skeleton-structures it was most probably at that time a dead specimen. What remains of the sarcode of the interstitial membranes is nearly translucent, and occurs in detached masses, each of which is crowded with the minute sexradiate stellate retentive spicula. The dermal system is furnished with numerous large expando-quaternate connecting spicula, the radial shaft being attenuated. Their mode of arrangement is similar in design to those of Alcyon-cellum speciosum and Rossella philippensis; but their disposition does not appear to be so regular as in either of those species. The dermal membrane has been nearly all destroyed. A few small portions, in a tolerably good state of preservation, were found on parts of the margin of the cup; and these were spiculous. I found also a small piece of the external dermal membrane in situ in a tolerably good state of preservation ; and on this there were a few large simple porous orifices irregularly dispersed. This portion of the membrane appeared to be rather abundantly supplied with very minute attenuato-acuate defensive spicula ; and intermixed with them a few sexradiate stellate retentive ones were dispersed. The membrane is very thin and delicate in its structure, and it was coated |