Dr. J. E. Gray on Hyalonema Schultze. 375 
tached to Euplectella cucumer in the plate above referred to, as a 
mooring to keep them in their place at the bottom of the sea 
—that the collectors artificially bend up, for the purpose of 
packing, the barbed anchor-bearing spicules round the body 
of the sponge—and that what Dr. Semper considers the stem, 
which he compares to the coil of Hyalonema, may be only a 
bundle of the spicules which it has in common with other 
species of the genus Huplectella. 
The consideration of these questions is important, not only 
as regards the use of the peculiar barbed spicules of the genus 
Euplectella, but also in comparing them with the spicules of 
Hyalonema, and particularly as regards the relation that 1. 
Schultzei has to the sponge Luplectella or the coral Hyalo- 
nema, to which it has been referred. It is important to settle 
this question before we use this animal as an argument to de- 
termine the situation of the genus Hyalonema in the general 
system of nature. 
Dr. Semper objects to my remark, at page 275, that ‘“ the 
coil had lost its bark and animals,” like the specimens that are 
sent from Japan and dredged up in Portugal—observing that 
“it never had any animals,” which is quite consistent with 
the theory of its being a sponge nearer to Huplectella than to 
Hyalonema, and proves, if my theory is correct, that it cannot 
belong to the latter genus. 
Of all modes of introducing ambiguity and confusion into 
science, none is half so effectual as the use of ambiguous names. 
One name for one animal is the first principle of natural science. 
Dr. Semper states that it cannot be a Huplectella, as the body 
of that sponge is reticulated, the longitudinal spicules being 
crossed in the bundle by horizontal and oblique ones, while 
the body of H. Schultzec is only formed of longitudinal spi- 
cules without any transverse ones, and only kept in their place, 
so as to form an elongate oval cup, by the sarcode. All these 
ee are utterly at variance with all the characters that 
have given to the true Glass-rope or Hyalonema, and so 
much more similar to those that belong to Huplectella that I 
am induced to propose for the present that it be regarded 
as a new genus of sponges of the family Euplectellade, 
for which I would propose the name of Semperella. It may 
appear precipitate to propose a generic name for a sponge that 
I have not seen; but it is absolutely necessary ; for already 
so many things have been called Hyalonema that it requires 
the greatest attention, when one sees the name mentioned, to 
know what part of the Glass-rope the writer is speaking of, 
or if he is speaking of a sponge not having the slightest affi- 
nity to the Glass-rope. 
