184 Mr. W. S. Kent on a new Vitreous Sponge. 
the second type (Wyv.' Thomson), simple, stylate, slightly 
ith delicate ad- 
( 
fusiform spicules having the shaft covered wi 
pressed spines, appear also to be much more abundant in this 
species than in Holtenia Carpenter. 
In conclusion, a word of explanation is necessary for the 
generic title I have adopted here for this species, in place of 
that of Holtenia. 
inches long, surmounted at one extremity with a corona of 
twisted cords of siliceous spicula [equivalent to the fascicles 
forming the beard in H. Carpenteri] about two inches in 
length. These spicula are very similar in structure to those of 
the Hyalonema, merely differing in size.” 
Subsequently, and previously to Prof. W.'Thomson's creation 
and description o the genus Holtenia, Dr. Leidy recognized 
the necessity of forming a new genus for the reception of the 
very remarkable sponge just referred to, and bestowed upon it 
the title of Pheronema, adding the following essential charac- 
teristics :— 
“The body of the sponge is oblong-ovoidal, with the narrower 
end upwards. The upper extremity is conical, with a truncate 
apex, | vidio! a large circular orifice, and which forms the 
exit of the canal which descends into the axis of the sponge 
for almost half its depth, and which then appears to divide 
into several branches. Its surface exhibits an intricate inter- 
lacement of stellate siliceous spicula inclosing a tissue of finer 
Pan a of the same character, the whole associated by the 
ed remains of the softer sponge-tissues. 
^ F'rom the lower end of the sponge there projects a number 
a 
Rides cea cn MEI 
