288 Dr.J.E. Gray on the “Glass-Rope” Hyalonema. 
in the Museum of the Academy of Sciences of Philadelphia 
which has a corona of twisted siliceous spicula, about 2 mches 
long, which mainly differ from those of Hyalonema in size (Proc. 
Acad. Nat. Sci. Philad. 1860, p. 85). It is said to have come 
from Santa Cruz. May this not be a young Hyalonema in the 
sponge? The two specimens of the genus Hyalonema which 
Dr. Leidy examined appear to have been without the sponges at 
the base; and as the genus is found on the coast of Portugal as 
well as Japan, there is no reason one may not be found at Santa 
Cruz. 
Before proceeding to make some observations on the extra- 
ordinary theories that some zoologists, and some even of high 
repute, have entertained respecting this genus, I wish to correct 
an error into which I have fallen. 
Misled by the dry and imperfect state of the bark of the 
specimen which I first described, and also perhaps by a pre- 
conceived opinion that then existed that a bark-coral must be 
an Alcyonaria with pinnate tentacles, in the Synopsis of the 
British Museum (1840), and in a paper, on the arrangement 
of Corals, in the ‘Annals and Magazine of Natural History’ 
for 1859, I arranged the genus with the Barked Aleyonaria, 
and formed an order for its reception, under the name of Spongi- 
cole or Hyalophyta (Aun. & Mag. Nat. Hist. ser. 3. iv. p. 441). 
Professor Brandt in his work has shown that they are Zoan- 
tharia allied to Corticaria, or Polyzoa having many simple conical 
tentacles in two rows; and Professor Bocage has also shown this 
to be the case in the species found on the coast of Portugal. 
The Japanese species have twenty, and the Portuguese forty 
tentacles. 
Professor Schultze also figured the conical tentacles of the 
Japanese species, and shows that they are, like other Zoantharia, 
furnished with stinging darts (t.5.f. 4&5). This latter author 
goes so far as to describe the animal as a species of Polythoa, 
under the name of P. fatua; but of this more hereafter. 
I admit that I ought not to have made this mistake; for a 
closer inspection of the contracted cell of the polypes ought to 
have shown me that probably they had more than eight tenta- 
cles; and now my attention is called to the fact, I am asto- 
nished how it could have escaped my observation before. 
The specimens which I first described from Japan had the 
thinner tapering lower end of the coral inserted in a sponge of 
the genus Halichondra, the lower end of the axis forming a 
pencil of spicula at the base of the sponge. 
Professor Max Schultze figured three specimens similarly at- 
tached to a sponge, the outer surface of the sponge being in a 
much more perfect condition, showing the oscula, than in the one 
