Mr. W. S. Kent on a new Vitreous Sponge. 185 
sequence of the increase of zeal in the prosecution of deep-sea 
dredging-expeditions which is now being displayed, we have 
every reason to hope is likely very shortly to be still further 
augmented. 
Order VITREA, Wyv. Thom. 
Genus PHERONEMA, Dr. Leidy. 
Sp. 1. ——, Leidy*. 
Sp. 2. Carpentert, (Holtenia C.) W.'Th. 
Sp. 3. Grayi, W. S. Kent. 
The principal distinctive features of Dr. Leidy's species 
appear to be that the oscular region is produced in a truncate 
as in many of the old Greensand Siphonias, and that 
the fascicles of spicules forming the beard or rootlets of the 
Sponge are shorter than in either of the other species—a cha- 
racter, however, hardly to be regarded as essential. id 
does not particularize the characters of the smaller spicules be- 
longing to the different regions of the sponge—though doubt- 
less, on a closer examination, they would exhibit specific 
peculiarities. 
The specimens of Pheronema Gray obtained were taken in 
a depth of water varying from four to six hundred fathoms. 
The average measurements of these specimens are as follow :— 
; the Zoological Societies. The one given 
above is taken from the ‘Monthly. Microscopical Journal’ for June 1869, 
