'Monsieur Peron has described, in very splendid colour ing, a newly discovered luminous animal, which he calls Pyrosoma Atlanticum; and more recently it has been as certained that the whole of the newly separated genus emits light. By Spallanzani we are informed that four of the genus Pinnatula are phosphorescent; namely, the Grisea, Argentea, Phosphorea, and Grandis; and it has since been remarked, that the whole of this family are en dowed with the saute property. He also mentions five other luminous marine worms, of which he had not as certained the genera ; while, among those that inhabit shells, the Pholades have been observed to exhibit light. In Captain. Tuckey's voyage, we are informed that some species of Ilolothuria, and one of the genus Scyllarus, was found to be luminous, as was a species of Sulpa. In the latter genus, Dr. Macculloch has discovered a new species on the west coast of the Highlands, which he calls Moniliformis, and which is also luminous.
From Captain Tuckey's narrative we also learn, that twelve crabs were found to be possessed of this property ; but neither the species are described, nor the particular divisions in the new arrangement to which they belong. Probably Professor Smith had as little made up his mind on that subject as Dr. Macculloch, who has ascertained nine new and luminous animals of this wide genus on the coasts of Shetland and Orkney.
In the genus Medusa there appear to have been more luminous species described than in any other. It would have shortened the matter to have said, what we believe to be the fact, that every one of them is so; we, at least, have never seen a species that was not. Mr. Macartney, who has bestowed some trouble on this subject, has point ed out the Hemispherica and Scintillans as possessed of this property, but has, we know not why, supposed it to be limited. The Medusa pellescens has been described as luminous by Sir Joseph Banks, the Noctiluca and Dor sa by Forskahl ; and two others, one in the Mediterra nean, and the other at the Cape of Good Hope, of which no specific characters are given, are mentioned by Spal lanzani and Forster. We are surprised that these ob servers should have limited themselves to so scanty an enumeration, as they could neither have failed to sec many more species, nor, if they had inquired, to have found them all luminous. In the same manner have almost all our recent voyagers neglected this subject. Not one lu minous Medusa or other animal is mentioned in any of the Polar expeditions, nor in Kotzebue's long expedition, although provided with two naturalists. On our own shores many species are found, and the whole arc invaria bly phosphorescent; the most abundant, in point of num bers, among these, being the Aunts and the Cruciata.
Very recently Dr. Macculloch has added twenty-one new species to this genus, and has also ascertained that the whole of them were luminous.
We shall terminate this miscellaneous list, by men tioning some other animals, ascertained by the observer last mentioned to be equally phosphorescent, all of them being found on the northern coast of Scotland and the islands. As many of these are new species, and some of them new genera, to which he has not yet given names, we can only make this enumeration in a general manner.
Besides the species of the genus Nereis above mention ed, he found some Scolopendrae which appear to be non descript kinds. In the genus Phalangium there was one, together with some in the genera of Oniscus and lulus. Of the animals of the genus Vibrio, formerly mentioned, taking that genus as it is now constituted, there were nineteen species, of which seventeen appeared to be new. Sixteen of those belonged to that department of luminous animals which do not emit sparks, but produce a pale and diffused light. But he considers the whole as properly divisible into four genera, to one of which he also pro posed to acid three or four more nondescript animals, similar in their leading characters to some which Muller has disposed of, without any regard to their essential dis tinctions.
In the genus Vorticella six or eight new species were found ; and these also were ascertained to be among the animals which cause the general diffused light formerly described. A similar number was found in the genus Volvos, and equally unknown, microscopic, like the for mer, and in the same manner assisting in producing that . kind of general phosphorescence. Two or three new species were also observed in the genus Cercaria. Others, equally minute, might be referred, as Muller has done with some corresponding animals, to other genera in the division of Infusoria ; but being dissatisfied with the construction of these genera, Dr. Macculloch declines to arrange them in that manner. We can only therefore add, in terminating this list, that in this very short course of observations, amounting only to six weeks, 190 lumi nous species were ascertained ; none of them having been observed to be luminous before, and a great number of them being undescribed animals. Those wanting to complete that number, in addition to what has already been enumerated, must be thrown into new genera ; and among them is included one fish, which in itself must form a new genus.