1 18 DR. J. i:. (;kay on hyalonema lusitanicum. [Jan. 2-1, 



iiie that the coral from Japan and that from Portugal should be 

 separated from each other as genera, having a different number of 

 tentacles, and that they must live under very different circumstances. 

 The differences have been pointed out by Professor Bocage in his 

 papers on the Portuguese Coral in the Society's ' Proceedings.' 

 The genera may be thus defined : — 



1. Hyalonema, Gray, and Brandt? 

 Hyalochceta, Brandt. 



Polypes with twenty tentacles in two series. The axis bare at 

 the base, living sunk in the centre of a sponge, and separated from 

 the sponge by a hard condensed coat. The bark strengthened ex- 

 ternally with siliceous granules or sand. 



All the perfect specimens which I have seen of this coral were 

 attached to sponges ; they are about twelve in number ; and there 

 are three figured by Brandt, and one by Schultze ; so there can be 

 no doubt tliat it is the natural habit of the coral. This seems to be 

 the case with all the specimens that have been collected by natu- 

 ralists. 



The Japanese seem to destroy the bark, and separate the corals 

 from the sponges, as they appear to consider the bundle of spicula 

 tlie most interesting part of the coral ; so that most of the specimens 

 that are brought to this country either have only a small part of the 

 bark attached to them, just enough to keep the spicula together, or 

 are entirely stripped of it. 



Hyalonema sikboldii. 



Hyalonema sieboldii, Gray, P. Z. S. ii. (IS35) p. 6.5 ; 1857, p. 279; 

 Institute, 1835, p. 426 ; Ann. & Mag. N. H. 1850, vi. p. 306 ; 1866, 

 xviii. p. 295 ; Perty, Allg. Naturg. iii. 1841, p. 796 ; Brandt, Bull. 

 Scien. Acad. Sci. St. Pe'tersb. n. s. xvi. 1857 ; Me'lang. Biol. ii. 606 ; 

 Symbolce, 14, t. I. f. i-10; Milne-Edwards, Coralliaires, i. 1857, 

 p. 324 ; Max Schultze, Die Hyalonemen, 1860, t. 1. 2 ; Bowerbauk, 

 Brit. Sponges, i. 196. 



Hyalonema mirabilis. Gray, P. Z. S. 1857, p. 279. 



Var. ? Hyalonema apinis, Brandt, Symbols?, 16, t. 2. f. 2 «, 2 b, 

 3 & 4. 



Hab. Jajian. 



Professor Brandt has divided the Hyalonema from the Japanese 

 seas into two genera, viz. Hyalonema and Hyalochceta, according to 

 the prominence and clustering of the polypes. I have not seen any 

 specimens which agree with Professor Brandt's Hyalochceta possieti. 

 Bull. Sci. x-Vcad. St. Petersb. xvi. 1857; Melan. Biolog. ii. 606; 

 Symbolse, 1 7, t. 2. f. 6-10. 



In the British Museum there is a sj)ecimen, which was brought 

 from Japan by Dr. W. Lockhart, that has some of the polypes 

 clustered and more })roduced than the others. It is almost inter- 

 mediate in form between the common state of Hyalonema sieholdii 

 and the figure of Hyalochceta possieti given by Professor Brandt. 



