Dr. J. E. Gray on the “ Glass-Rope” Hyalonema. 295 
ing them as parts of the same animal” (Ann. & Mag. Nat. Hist. 
1859, iv. 441). And the discovery of a second species in Japan, 
and a third on the coast of Portugal, in all of which the bark 
and axis are found together, I think entirely destroys any idea 
that there is the slightest reason for believing the theory 
propounded by Valenciennes, and which has been so readily 
adopted, I may almost say without re-examination, by other 
naturalists, 
This theory has had the effect of confusing the nomenclature 
of the Japanese species, which I first described as under :— 
I. The coral consisting of the bark and azis. 
Hyalonema Sieboldii, Gray, P. Z. 8. 11. 1835, p. 63 ; Brandt, Sym- 
bole, &c. t. 1. f. 1, 10. 
Halinema, Ehrenb. Monatsb. Berlin, 1840, p. 2 & 3 (a misprint ?). 
II. The bark only, without the axis or sponge. 
Polythoa fatua, Max Schultze, Hyaloneme. 
III. The sponge without the rope-like axis or bark. 
Spongia octancyre, Brandt, Symbole, 14, note; Ehrenberg, 
Monatsb. 1860, p. 170. 
Spongia crucigera, Khrenb. Monatsber. 
IV. The sponge and the elongated united axis without the bark and animal. 
Hyalonema Sieboldii, Max Schulize, Die Hyalonemen, 9. 
Hyalonema mirabilis, Gray, Bowerbank, Brit. Spongiade, 49. 
Hyalonema, Valenciennes, Milne-Edwards and Haime. 
This coral, which was first regarded as a plant and then as a 
sponge, has been considered by one of the first microscopists 
an artificial production! Thus Professor Ehrenberg, in an 
elaborate paper in which he gives an abstract of the various 
essays that have been written on the Hyalonema Sieboldii, con- 
cludes thus :— 
“‘Glass-corals must be considered an artificial production, not 
less than those Indian idols produced in the shells of mother-of- 
pearl. The long siliceous threads, widely distributed over the 
Pacific, are with much labour collected in small quantities, pro- 
bably from an unknown large species of Tethya; they are 
formed into bundles, which are forced into or through the tubular 
leather-corals allied to Polythoa, so that the fine end of the 
bundle, which is first pushed through, remains simple, whilst 
the remainder obtains a spiral form through the rotatory mani- 
