some of these are deserving of more than a passing notice, it may not be out of place to record their occurrence. Among the raptorial birds, the most distinguished visitors (for they no longer breed there) are the golden and white-tailed eagles. These are chiefly seen in autumn, and are supposed to be attracted to the place by their chances of subsisting upon the entrails of rabbits, which are at that season killed by the tacksman, and disembowelled previous to being sent on shore. The peregrine falcon, which is not uncommon, still breeds there, and from his great powers of flight regales himself and young with prey not obtainable on the rock, though the supply is ample. The kestrel, the white owl, and short-eared owl are also natives of the rock. The raven and carrion crow, though systematically shot at, maintain their ground, and bring up their families upon the eggs and callow young of the sea-fowl, long after they have quitted the nest. The corn-crake is occasionally seen with its brood, and the thrush and blackbird both build their nests in the old castle ruins, and among the rocks, at an elevation of 500 or 600 fect. The wheatear is a familiar tenant, and the snipe and woodcock are both common at certain seasons.

Of the gulls there are found breeding on the grass-covered summit five or six species-the kittiwake being, perhaps, the most numerous. The greater and lesser black-backed gulls are also abundant, as well as the common gull (Larus canus), and the herring gull, all of which keep within their own territories, the sanctity of which, however, is occasionally outraged by their piratical visitors the skuas. The Iceland gull is the rarest of the family; it is, however, seen in small numbers every summer, and is well known to the keeper. On warm summer evenings I have observed this bird feeding after dusk; and during the day, indeed, it is constantly dozing upon rocks at the foot of the craig, near the water. The ringed guillemot (Uria lachrymans) is not uncommon. I have never had any difficulty in obtaining this species from the keeper, who goes in search of it when wanted, and selects his bird, cleverly snaring it with a hair-noose on the end of a pole. The little auk (Mergulus alle) has been seen in summer, and the storm petrel breeds under the loose stones at the base of the cliffs. On dull days I have seen the bird issuing from these retreats at mid-day, following our boat two or three miles towards the mainland,

NOTES ON THE NATURAL HISTORY OF THE
NATTERJACK.

BY JONATHAN COUCH, F.L.S., ETC.

THE Natterjack is a kind of toad, the existence of which was not known in the British islands until it was made known by Pennant, and to him the information was communicated by Sir Joseph Banks. But there was scarcely anything given of its history or manners. Pennant says that it frequents dry and sandy places, but it is known to the writer only as it is found in places much the opposite of this; although the difference may arise only as its residence and habits are affected by the change of seasons; or by the influence arising from the impulse to deposit its spawn in a congenial situation, which within our observation has only been in pools of rocks so close to the open sea as to appear to be every instant exposed to be broken in upon by salt water. At the most a foot or two of the bare rock is all that lies between the favoured situation and the open sea, so that a little roughness of the waves appears to be at any time sufficient to throw the sea into the place; and in some instances it was noticed that there were pools tenanted by the rockgoby, a fish which must have entered them from the sea, which lay on the same level with those which were occupied by the natterjack. But it was a subject of surprise that the latter could have been able to enter the pool, in consequence of the almost inaccessible situation of the place to such a creature from the land. On closer examination, however, it is constantly to be observed that these selected pools are in a damp place, where a draining of fresh water from the more elevated cliff is constantly dribbling into them; so that the water in which the spawn is deposited is but little, if at all brackish. Natterjacks make their appearance in these situations about the end of March, or at the early part of April; and it appears that in habitually selected spots they come all at once, and without loss of time they begin to perform the functions which have brought them together. This early proceeding is the more immediately necessary as there is scarcely any shelter in the place by which to conceal themselves or their actions; for the water is too fresh for the growth of seaweeds, and too bare to permit plants which might grow in fresh water to establish their roots. In consequence of the exposed situation of these places of resort it sometimes happens that these unprotected animals are destroyed by ignorant persons, who have thought their slaughter a meritorious act.

The shedding of the spawn is probably accomplished in the night, and seems to be effected with considerable labour, and

also to occupy a considerable length of time in the performance. From some circumstances also which attend the proceeding there is reason to believe that it is performed in a different manner from that by which this function is executed in the common frog; and if so, it seems to follow that the fertilization is accomplished while the ova are yet in the body of the parent. Thus in one instance a couple of females without a male were in occupation of a pool in the rock, in which fortunately for them some roots of a flag remained from a former growth, and which, although adhering to the bottom, remained otherwise exposed. To these the long strings of spawn were attached. The arrangement of the grains being alternate in two rows enclosed within a lengthened case or band of mucus; and as these strings were in some parts much entangled together, I was at some pains to disentangle and measure them. I judged one of these strings to measure nearly, if not quite one hundred feet, and the other was but little less; and assuredly our wonder must be excited in contemplating so great a length, excluded from the body of so small an animal. This indeed can only be explained by the consideration that a great increase of size is caused by the absorption of fluid as the string of mucus is dragged from the parent; and that the expression dragged is not inappropriate is again rendered probable by the fact that in the first place no male was found in or near the pool, although in one of them that was killed the full amount of spawn had not been excluded. And again, a portion of the chain or string was twisted round a stalk of the dead plant, and it had even been passed through a narrow opening between two portions of the stalk, through which the parent must have with difficulty drawn itself; but through which it appeared impossible that the male when attached to the female could also have passed. I have found a few sprigs of furze that had accidentally fallen into a pool, which had been used for the same purpose of forming a fixed point, and by which the string might have been drawn from the body of the female. In one instance, where there were only two females of this species, the separate strings of spawn measured each about twenty feet; and on opening one of them which had been killed there were found about half a dozen black grains still remaining in the ovary, together with a large quantity of minute grains of a similar kind but pale white, as if they constituted a new formation of spawn.

The grains of ripe spawn, when first shed, appear of a deep black colour, but closer observation discovers within each of them a pale cicatricula; the size of the grain being nearly that of a radish seed. But before I proceed to describe the order of their development, I would remark that, on one

occasion, a large number of these creatures had formed themselves into a mass, as is sometimes the case with the common frog; and again a considerable number were collected in a small pool of fresh water high on the cliff, with spawn near them. This last was the only instance I know of the kind, but there was no pool in the rocks bordering the sea, within a great distance of the place to which they could have resorted. Among the particular actions which further characterize this species of toad, it is to be noticed that all the motions of a company appear to be carried on simultaneously; as if there existed an understood agreement between them, or that one pervading impulse was acting on the whole. Thus they are usually, if not invariably known to appear all together, and when they go away, it is in the same manner; and a curious instance of this occurred to a man of the coast-guard, who has often exerted himself in supplying me with examples of various sorts in Natural History; and who took three individuals of this species from a pool, out of a larger number that were in it, and placed them in a room in a bucket of water, that they might be at hand in the morning; but they made their escape in the night in a way that could not be explained; and, on going to the pool again, not one was to be found. This disappearance is the more remarkable, as no example of the Natterjack has been met with at any other than the breeding season through the extent of our coast. That the several stages of the progress of evolution in the ova might be better observed, some of these tadpoles were removed in a glass vessel to my dwelling; but, in the course of repeated visits to the pool, it was noticed that those which had been left to remain in their original situation had made greater progress towards maturity than such as had been removed, although even there I found much difference in the extent of development; so that it seemed probable that, even at the time of their being produced, some of the grains had been more advanced than others; or, perhaps, although the string was continuous, the length of time that had been required to bring the whole to light had been so considerable as to allow of a preponderating advance in the earliest over that which followed.

It might be thought, tedious to enter minutely into all the changes which the grains of ova were observed to undergo in their progress to the condition of a perfect animal, but their general appearance is, to some extent, marked in the sketches which accompany this paper. I first noticed the size and appearance of the young which had just become separated from the chain or cord of mucus-an advance which was accomplished in the space of five days from my earliest

observation; but the next following changes went on rapidly, and voluntary motion had begun at the end of twelve days from the exclusion. The eye was well formed at an early stage; but, although the spawn was first seen near the end of March, the middle of July had passed when the legs made their appearance; and this they did with some difference, for in some instances the feet of the hindmost legs were first protruded, and in others those of the first pair were first seen. At this time some were in possession of four limbs, with scarcely the vestige of a tail; and this is the period when the colour changes from black to bronze, which last-mentioned appearance is a sign that the creature is about to leave the water for the land. As the tail becomes less the body diminishes in size, so that, when the tail has disappeared, the body has become less than half as large as when in the tadpole state; the greatest breadth being a little behind the eyes. At this time, that is, a few days after the middle of July, being desirous of knowing what effect the presence of sea-water would have on these little creatures, I removed from their native pool three specimens which had obtained their fore-legs, but still possessed a small remnant of tail, together with one which was furnished with only two legs and a tail at its full length. To the water in which they were placed there was added a fourth part of sea-water, with which mixture in a few minutes they were greatly affected, and after a quarter of an hour those with the legs appeared to be dead. One of them lay with its mouth wide open, and the legs of the others were stiffly stretched out, and they were thrust about unconsciously, sometimes on their backs with the motion of the water; while that one which still retained its tail appeared to be little affected, so that in its movements it thrust about its companions at pleasure. They remained in this condition for half an hour, after which this water was removed, and fresh water from a brook supplied to them; in which for another half hour the apparently dead tadpoles remained in the same condition; but, having set the vessel aside for two or three hours, when next examined they all were as lively as at first. It appears, therefore, that a mixture of sea-water is fatal to them at a later stage of growth, but that at first it does them little or no harm.

On the following morning the tadpole with the tail had acquired its fore-leg on the left side, and by the evening its companion leg had appeared; both of them perfect in form, but bent on themselves, and enclosed in a membranous sheath. The growth of these legs in stoutness is rapid, and presently after their appearance the body behind the aperture of the gills contracts in its dimensions. The margin of the fin on the border of the tail becomes waved before the hindmost legs