264 Dr. J. E. Gray on Hyalonema Sieboldi. 
Mr. Gregory sent with this coral a very interesting speci- 
men of Hyalonema Sieboldii. It is attached to a sponge 
which shows on the surface the numerous circular and oblong 
(this form being perhaps produced by compressing the open 
mouths) oscula, surrounded by a slightly raised edge, which are 
figured in Professor Schultze’s plate. The presence of these 
oscules shows that the prominences in the bark cannot be “ the 
oscule” as Dr. Bowerbank supposes. 
The coil is very short, very thick, and formed of a large 
number of short spicules. These spicules, though short, are 
complete ; for they taper at the tip, and exhibit the usual ap- 
pearance of perfect spicules; otherwise it might have been 
supposed that this was only the base of a longer coil. The 
coil is a full inch in circumference at the base, and spread out 
towards the end. It has unfortunately been entirely deprived 
of its bark, except just where it emerges from the sponge, 
where there is a narrow imperfect ring of the bark, with 
small-sized circular prominences, being the contracted po- 
lypes, which are raised considerably above the surface, and 
have a small central impression. The coil is about 8 inches 
long; but one or two of the spicules are nearly one inch 
longer. 
Every specimen that I see of this production more and more 
confirms my first idea that the coil and bark constitute a coral 
which is connected with a parasitic sponge. 
XXXII.— On a new Free Form of Hyalonema Sieboldii, and 
its manner of growth, By Dr. J. HE. Gray, F.R.S., 
WEEE Zi. oA Lisp: 
Mr. W. Currer has most kindly sent to me for examina- 
tion a series of seventeen specimens of Hyalonema Sieboldii, 
which he had just received from Japan. They are all in good 
condition, better than most specimens when they arrive. The 
bark in all but one is decidedly in its natural state; this, on 
the other hand, certainly has been entirely stripped of its 
bark, and fresh bark recently stripped from some other speci- 
men has been artificially put on to it; it would almost appear 
as if the coil of two specimens had been twisted together into 
one. 
The series shows two very distinct varieties—one the kind 
hitherto known, which is found affixed to a sponge, and the 
other a free form of the coral, which is covered with bark 
to the very base of the coil. Of the sixteen specimens in their 
natural state, nine belong to the first, and six to the latter or 
free variety. 
