4122 THE DEPTHS OF THE SEA. [CHAP. Ix. 
The genus was first known in Europe by specimens 
brought from Japan by the celebrated naturalist and 
traveller, Von Siebold; and Japanese examples of 
Hlyalonema sieboldi, GRAY, may now be found more 
or less perfect in most of the European museums. 
When the first specimen of //yalonema was brought 
home, the other vitreous sponges which approach it 
so closely in all essential points of structure were 
unknown, and the history of opinion as to its rela- 
tions is curious. 
The being consisted of three very distinct parts: 
first, and greatly the most remarkable. the coil of 
silicious needles; then the sponge,—and for long it 
was supposed that this was the base of the structure, 
from which the glossy brush projected, spreading out 
above it in the water; and thirdly, the apparently 
constant encrusting zoophyte. 
This complicated association suggested many pos- 
sibilities. Was Hyalonema a natural production at 
all? Was it complete? Were all the three parts 
essentially connected together ? And if not, were all 
the three independent, or did two of three parts 
belong to the same thing ? and if so, which two ? 
Hyalonema was first described and named in 
1835 by Dr. John Edward Gray, who has since, 
in one or two notices in the ‘Annals of Natural 
History’ and elsewhere, vigorously defended the 
essential part of his original position. Dr. Gray 
associated the silicious whisp with the zoophyte, 
and regarded the sponge as a separate organism. 
He looked upon the silicious coil as the representa- 
tive of the horny axis of the sea-fans (Gorgonie), 
and the leather-like coat he regarded as its fleshy 
