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Alder, whose name is well known as an able and enthusiastic naturalist, informed Dr. Johnston that the species of sea-mouse previously mentioned, the porcupine sea-mouse (Aphrodita hystrix), “are very inconvenient neighbours in a bottle, as their sharp spines stick into everything, and in examining the contents of a dredge where they are,” he adds, "they pierce the fingers, breaking in, and becoming very painful.” These Ascension boatmen may be aware of something of the same nature, and no doubt the numerous setæ with which the feet of this worm are clothed are powerful weapons of offence and defence against those animals which prey upon them, and may at times, in like manner as those of the porcupine sea-mouse mentioned by Mr. Alder, prick the fingers of those who incautiously handle them when alive. A similar-looking species was taken by M. Bory St. Vincent, amongst the rocks and lava off the coast of Metava in the Morea. The colours of this species were almost as bright as the one just mentioned, and it is rather remarkable that both are natives of the vicinity of volcanic islands. It is curious that worms of this brilliant character should be found buried in the ocean where no mortal eye can observe them. Doubtless, these resplendent colours are of some use to the animal so highly adorned, though we may not exactly understand it; but we are strongly reminded of the beautiful words of the poet :
“Full many a gem of purest ray serene,
The dark unfathomed caves of ocean bear.
And waste its sweetness on the desert air."
One or two species of an allied genus, named Euphrosyne, are natives of our seas. One of them, Euphrosyne foliacia, has been taken on the coast of Ireland and at Weymouth. In this species the crest is erect and linear; but the branchiæ are rather small, being no longer than the setæ of the feet. The colour of this Annelide when alive is said to be of a fine cinnabar red, very bright upon the branchiæ, and mixed with yellow and green on the back. The cirri are yellow with a red line running along the centre. The crest is of a brighter red than the back; the belly is of vinus colour, and a bright red line runs down the middle. Mr. Gosse, who has observed it when alive in Weymouth Bay, says that the colours of his specimen were less vivid. “I should designate the hue," he says, “to be of a bright cinnamon red, rather than cinnabar; and the median line of the ventral surface is purplish.” In length it is three-quarters of an inch.
Family EUNICEÆ.—The worms belonging to this group are peculiarly formed with regard to their masticatory organs. Their proboscis is short, but has, articulated on its base, from seven to nine solid jaws, placed one above the other, and approximated beneath so as to rest on a kind of inferior lip of a similar or even more solid structure. The species are generally of a linear, elongated, almost cylindrical form, and the body is composed of numerous segments. They have no scales or elytra on the body, and may or may not possess branchiæ or gills on their feet. These latter organs consist of only one branch, but are furnished with one or more fascicles of bristles. In the genus Eunice the spines are provided with branchiæ which are very distinctly and well developed. They are fixed immediately above the upper or dorsal cirrus, and are more or less pectinate or comb-like in their structure. Standing erect as minute combs at the dorsal base of each foot of the body, to use the words of Mr. Williams, these branchiæ impart to all the species a graceful and characteristic appearance. The Eunices, even on coasts, are of considerable size; but some of the exotic individuals measure more than four feet in length, and possess more than four hundred segments in the body. The jaws are remarkable bodies; as represented in Plate II., Fig. 5, they are three pairs, and are powerful organs. The two uppermost are large, simple, and curved at the point (bb); the two inferior are shorter, but thicker and more massive than the superior, and are toothed in the inner margin (cc). The third pair are called denticles by Quatrefages, are small and armed with teeth on their fore margins (d d). On the inferior part of the proboscis we see the inferior or sternal lip (Fig. 5, a), upon which these jaws, as it were, rest. This consists of two flattened bodies united strongly to each other in the centre, and free from teeth on the margin. The jaws are all solid horny bodies, but the lip itself is almost calcareous in structure. The species from which the figure of these jaws is taken, Eunice (Marphysa) sanguinea, the Sanguine Eunice, is the finest of all our European species. It was first described by the celebrated naturalist and historian of the lower animals of our coasts, Colonel Montagu, who discovered it on the southern shores of England.
In size it far surpasses all our other British species, being from fifteen to twenty-four inches in length, and as thick as a man's finger, the body consisting of three hundred segments. Most of the species of the genus Eunice are furnished with two tentacular cirri on the second segment of the body; but the Sanguine Eanice differs from all our others in the absence of these
want of tentacular cirri has caused it to be raised to the rank of a separate genus, called Marphysa. The colour of the body when it is alive, is generally of a deep green, with intensely red branchiæ. But these colours vary very much according to the situation in which these animals occur. When they are found, as they often are, in the clefts of rocks, sheltered there, and living in a sort of gallery, which they construct for themselves, they are richer in their tints, and are adorned with metallic and iridescent hues. If taken amongst sea weeds and Zosteræ in a muddy bottom, they partake somewhat of the dull colours of their residence, become less brilliant, and of a darker hue.
Amongst the other genera belonging to this group of Euniceans, there are one or two which inhabit tubes. Such is the Sao (Northia tubicola of Johnston, the Nereis tubicola of Müller), and the Onuphis conchilega of Sars. The former of these worms, the Sao, lives in a tube which it constructs for itself, and which presents the exact appearance of a quill pen. It is of a horny substance, about four inches long, smooth and transparent, and somewhat flexible. Living in soft mud, the animal immerses in it one end of this tube, and protrudes the other end to some distance. The habits of this worm have been described with great accuracy by Dr. Johnston, whose words we quote:
“ One unceasing object of its life,” he says, “is the capture of prey. For this end, it must protrude the anterior portion of the body beyond its tube, and raise itself above the surface of the mud, and remain in this position on watch. To enable the worm to do this with ease, is, I conjecture, the office of the forceps-like bristles of the feet (Plate I., Fig. 7); with their ends, it may hook itself to the rim of the tube, and thus obtain a support without the waste of muscular power. A long watch is thus rendered less irksome, while at the same time the capacity to seize upon a passing prey is increased. The prey caught, analogy leads us to conclude that the worm will instantly retreat and sink within its tube, where it can feed without disturbance or fear. But as the entry and passage are narrow and unyielding, it seems to follow that the prey should be held by the mouth alone, when in the act of being dragged within the tube, and hence surely the reason that the mouth has been furnished with the hard tubercles to the lips; for, when pulled together and put in contact, they must give a firmer gripe and hold than could otherwise be taken. The use of the tube is to protect the body from the pressure of the soft mud in which it stands immersed. When the tube is overset or cast out by the waves or
accident, the worm leaves it, and becomes in its turn exposed to enemies. To protect itself from these, while a new tube is being secreted, nature has amply furnished the Sao with a series of bristling lances on each side. These arms are of exquisite make, very fine and very sharp; and those of the upper bundle have their points bent and inclined towards those of the lower bundle, which are likewise bent to meet them. Arms like these will inflict wounds on the tiny assailants of the Sao, sufficiently painful to repulse them, and a lethal wound is unnecessary.”
The Eunicean worms mentioned above are all provided with gills or branchiæ on their feet; but, as we stated at the commencement of the group, there are others which do not possess these organs. Such is the fine long worm found on our coasts, the Various-coloured Lumbrineris (Lumbrineris tricolor). The head is oval, entire, and without eyes, antennæ, or palpi. The jaws resemble those mentioned above in the genus Eunice, but are more in number, being four pairs, placed opposite each other, and supported on a short stalk composed of two pieces. The Various-coloured Lumbrineris is a native of our more southern coasts, and is about ten inches long. It is narrow, being only about a fourth of an inch in breadth, and is smooth and iridescent, with brilliant blue reflections in the sutures of the body. M. Quatrefages informs us that these worms are very lively animals, twisting and turning their long bodies with surprising rapidity. The greater number of species, he says, secrete, shortly after their capture, a very large quantity of mucus, which soon becomes of a very tenacious character, and transparent as glass. The quantity exceeds in volume the size of the animal which exudes it. The species of Lumbrineris live in subterranean galleries, like earth worms, which they in reality considerably resemble in appearance.
(To be continued.)
PHILLIPS ON VESUVIUS.*
PROFESSOR PHILLIPS has produced a classical work on the most interesting of European volcanoes. In it he has collected together a mass of matter of the highest scientific import, while his clear descriptions and graceful style will secure for his labours a wider circulation amongst the class of general readers than is often attained by an exact and learned book. The work is illustrated by eleven plates, and thirty-five “diagrams,” some of which are justly so designated, while others are artistic sketches made by the author, and evincing no ordinary amount of technical skill.
The early history of Vesuvius as a volcano is unknown. Previous to the great eruption of A.D. 79, the mountain had experienced a long period of repose. Seneca, who lived a little earlier than the outburst of 79, noticed the eruptive character of the adjacent rocks, and Strabo, about 30 B.C., "remarking the cindery aspect and cavernous rocks, as if eaten by fire, conjectured that in ancient times the country was all in a state of burning, being full of fiery cavities, though now extinct for want of fuel ;” and he adds, “ Perhaps this is the cause of its fertility.” Vitruvius is also cited by Professor Phillips as having preserved a tradition that at some period, which had become antique by the time of Augustus, Vesuvius had vomited fire amongst the fields; and Tacitus is quoted to show that, in his mention of the eruption in the reign of Titus, he speaks of that incident as a repetition of what had occurred “long ages before.” Diodorus Siculus (B.c. 45) likewise states that “the whole region was named Phlegræan, from the culminating point now called Ovecovios, bearing many indications of having emitted fire in ancient time."
The fertility of the soil and the long continuance of rest had encouraged the growth of a numerous population within a few miles of the mountain, and their first alarm seems to have been excited by earthquakes, one of which shattered the cities of Pompeii and Herculaneum at the time when Nero made his appearance on the stage at Naples. The earth-shakings continued for sixteen years, till on the 24th August, A.D. 79, they made the "whole country reel and totter," and then came the eruption, in which the elder Pliny lost his life, and which destroyed the two cities, and covered a large tract of country with suffocating ashes. If the elder Pliny
* “Vesuvius," by John Phillips, M.A., Hon. Fellow of Magdalen College, Oxford, D.C.L. Oxford, LL.D. Cambridge, LL.D. Dublin, F.R.S., F.G.S., Professor of Geology in the University of Oxford. Oxford, at the Clarendon Press.