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Page:Popular Science Monthly Volume 3.djvu/553

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THE GLASS-SPONGES.
537

rugose, having almost imbricating rings. Beheld for the first time under the microscope, its sight recalled the appearance of the hairs of a hat. I have convinced myself that this is the functional intention of the frayed end of the fascicle, by a careful examination of a suite of specimens obtained for me at Enosima, Japan, by Prof. Griffis, of the Imperial College at Yeddo.

But the deep-sea dredging described in Dr. Thompson's book sheds much light on the Hyalonema. Says the writer: "When we trace its development, the coil loses its mystery. In two or three hauls we got them in every subsequent stage—beautiful little pear-shaped things, a centimetre long, with a single osculum at the top, and the whisp like a small brush. At this stage the Palythoa is usually absent, but, when the body of the sponge has attained 15 mm. or so in length, very generally a little pink tubercle may be detected at the point of junction between the sponge-body and the coil, the germ of the first polyp."

Fig. 4.

Pheronema Annæ. Half the natural size. A glass-sponge, obtained at Santa Cruz, W. I.

Allusion has been made to the ingenious manipulation of these glass-sponges by the Japanese. Says Dr. Hadlow, then in Japan: "We sometimes meet with portions of the glass coil most ingeniously attached to and grouped with corals, shells, and other ma-