Dr. J. E. Gray on Hyalonema Schultzei. 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 j may be only a 

 bundle of the spicules which it has in common with other 

 species of the genus Euplectella. 



The consideration of these questions is important, not only 

 as regards the use of the peculiar barbed spicules of the genus 

 EupUctellaj but also in comparing them with the spicules of 

 Hyalonema^ and particularly as regards the relation that H. 

 Schultzei has to the sponge Euplectella 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 Euplectella 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 Euplectella^ d,^ 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 Schultzei 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 

 particulars are utterly at variance with all the characters that 

 I have given to the true Glass-rope or Hyalonema^ and so 

 much more similar to those that belong to Euplectella that I 

 am induced to propose for the present that it be regarded 

 as a new genus of sponges of the family Euplectellad^, 

 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. 



