Sir John Dalyell, in his interesting paper entitled Further Illus trations of the Propagation of Scottish Zoophytes' (` Edinburgh New Philosophical Journal,' April-July, 1836), gives the allowing account of the propagation of the halm Speaking of Alcyonium, he says, "We find it consists of a compact gelatinous or fleshy matter, studded sembles a leaf divided into subordinate parts, one of the surfaces being studded with cells, and the other exhibiting elevations or con vexities corresponding to their bottom, and the whole product is of a yellowish colour. Each cell, of a shuttle or slipper shape, level with the surface of the leaf, is inhabited by a vivacious polypus, exercising a percussive faculty both of the tentacula individually and of the whole head. Some of the cells are occupied occasionally by large bright yellow, irregularly globular, solid, ciliated animalcula, subse quently quitting them to swim heavily below. In several days they become motionless like the former, and die also without immediate decomposition. Next, there appears in just about the same spot below, occupied by the motionless animalculum, a yellow nucleus with a lighter diffusing margin. This in its further diffusion assumes a shuttle or slipper form ; it becomes a single cell, which afterwards displays a polypus under the wonted figure and action. The adult Flustra WAS vertical, for the leaf is always erect; but here the new cell is horizontal. By a singular provision of nature, as only one side of the adult is cellular, the original cell is necessarily a root, sole, or foundation to admit subsequent enlargement, which in such zoophytes is always from a single cell. One end of the cell next rises vertically, wherein a second cell, with its polypus, is soon displayed overhanging the first, and at right angles to the plane of its position." (See also Professor Grant's Observations on the Polypes' of this species in the `Edinburgh New Philosophical Journal.') Example, Flustra aricularis. Locality, European seas ; Seaford Bay, Sussex.
This species however should be removed from the genus Flustra altogether, as its affinities are clearly with that of ilugula (Oken). It is the B. (Avicularia) flabellata, J. V. Thompson, Manuscript, Brit. Mus.,' and its avicularia, or 'bird's-head' processes, from their size and transparency, are well adapted for the investigation of the structure of those curious organs.
5. Elzcrina. Animals unknown, contained in sufficiently large oval elongated subhexagonal• bordered cellules, having a membranous tympanum or drum, in which is pierced the sigmoid opening, forming by their quincuncial and circular arrangement the branches of Example, CeEaria Salieornia (Cellularia Salleornia of Pallas/ Tabu/arta fist close of Limneus). Locality, European seas.
membranous, plaut-like, non-articulated, dichotomous, and fixed polyxoarium.
Example, Elzerina Blainrillii. Locality, the seas of Australia.
De Blainville observes that this genus was established by Lamouroux for a polype bronght from the seas of Australia by Picron and Lesueur, which De Blainville examined in Lamouroux's collection, and that he has been satisfied that it is a genus which can hardly be distin guished from the phytdid or plant-like Flustme, —that it differs from them only in the union of the cellules, which form a circular quincunx, as in Ce Salieornia, and are still more soft and membranous.
Riaso records two species of Elzerina in the Mediterranean, E. renusta and E mutabilis ; but De Blainville observes, that if it be true that their cellules are scattered, it is probable that those species do not belong to this genus, the characters of which it must be con fessed are by no means at present well defined.
a. rineu/aria (recent and fossil). Animals unknown, contained in oral subliexagonal regular cellules, having a aubterminal semilunar orifice, and applied and united longitudinally in many rows, so as to form a cretaceous brittle polyxoarintn, in the form of a little wand.
Example, rincm/aria fragilis. Locality of the genus at present known, the Calcairo Tertiaire of Westphalia. A recent species occurs In tho Pacific or Australian seas, and is figured In Cat. Brit. 3Ius.' FL 85, gigantea.
De Blainvillo observes that this genus was established by Defiance, and that it has been adopted by Holdfum under the denomination of (7/qwee1fama, a denomination which De Blainville rejects, remarking that Goldfints regards it as approaching nearly to Cellaria Salicornia, and stating that the rincalaria fragilis which he (De Blainville) examined in Defrance's collection might well be nothing more than a true Fludra, which is found in the same beds with P. frogilis. De adds in support of this opinion that Defiance showed him a specimen which was composed of two rows or series, instead of a single series only.
7. Sa/ieornarta. Cells disposed around an imaginary axis, forming cylindrical branches of a dichotomously divided erect polyxoarium.
a. Species with Hexagonal Cellules, and with a transverse aperture.
(Geniis, Salicornia of Curler.) S. Species with Oval Cellules, and the aperture rounded and tubular.
Example, C. ceroides (Sertuloria eeroides of Gmelin). Locality, Mediterranean and the Indian seas.
De 131ainrille observes that this genus, established by Pallas under the name of Celfularia, has been successfully simplified by Lamarck and by Lamouroux, who has esta blished many genera at its expense. Do Blainville further states that before Delle Chide no author who had described a species of a true Cellaria was known ; but that the Neapolitan observer had filled this gap by informing us in his Memoirs that the polypes of C. cerades bear a perfect resemblance to those of Milltpora (2If yriapora) truneaea. Pallas made a curious observation relative to the rapid , growth of C. 8a/icor-ilia ; for he found individuals an inch and a half long upon the eggs of Squali, which were still far from the time when the young are excluded.