484 



MISCELLANEOUS. 



Note on Hyalonema boreale, Loven. 

 By Dr. J. E. Gray, E.R.S. &c. 



Dr. Loven, in the 'Ofversigt' of the Swedish Academy for 1868, 

 p. 105, describes and figures in detail a small sponge under the 

 name of Hyalonema boreale. 1 hope shortly to receive a translation 

 of this paper from the author, for insertion in the * Annals ;' and I 

 have no doubt it vsdU contain many interesting observations. 



Believing that facts were accumulating that would prove the 

 Hyalonema to be a coral, as I first described it, I was rather dismayed 

 when I heard from my friend that he was describing a northern 

 species of the genus that would prove it to be a sponge. On seeing 

 the paper, my difiiculty was to understand why so accurate and 

 philosophical a zoologist as Dr. Loven could have referred it to my 

 genus Hyalonema. 



HyaloneiTui boreale, Loven, is a typical siliceous sponge belonging 

 to my family Halichondriadae, of a pear-shape, with a single sub- 

 central terminal oscule, with a long cyhndrical pedicel, and fibrous 

 roots. In general form and structure and in form of spicules it 

 agrees so well with Halichondria Jtcus of Johnston, which is the 

 type of my genus Ficulina (see Proc. Zool. Soc. 1867, p. 523), that 

 I am inclined to refer it to that genus. But perhaps it may be 

 necessary to form it into a separate genus, characterized by the 

 length and structure of the pedicel and the absence of the pin- 

 shaped spicule ; but at present I should call it Ficulina borealis. I 

 cannot find that it presents a single character of the genus Hyalo- 

 nema. In that genus the elongated spicules that form the coil, 

 which induced me to call the genus Hyalonema (that is, glass rope), 

 arise out of the centre of a sponge with a flat expanded base, by 

 which it is attached to some marine bodies ; and the sponge is 

 furnished with numerous superficial oscules. In H. boreale, on the 

 contrary, the sponge is clavate, with a pear-shaped body on a long 

 slender cylindrical pedicel having a fibrous root. This pedicel is a 

 true part of the sponge, and cannot in any way be compared with 

 the coil of siliceous fibres that arises out of the upper part of the 

 sponge in Hyalonema. 



■ Dr. Loven observes : — " You will see that, if I am not very wrong, 

 all who have treated of the Hyalonema have inverted it, turned it 

 upside down, and that the twisted rope, instead of rising out of 

 the sponge, in reality is nothing but the remaining part of the 

 stalk." 



I fear Dr. Loven has only had very imperfect specimens of the 

 Japan Hyalonema to examine, or he could not have adopted such a 

 theory. 



Dr. WyvOle Thompson has informed me that he dredged a speci- 

 men of Dr. Loven's Hyalonema boreale a couple of years ago, in 

 Oban Bay. 



