Scarabæi solstitiales', or fern-chafers. The powers of its wing were wonderful, exceeding, if possible, the various

susceptible of delicate impressions, and acted upon by them to the performance of its special functions with equal acuteness and rapidity. The tragus, which exists in man only as a small lobe projecting in front over the auditory opening, becomes in many of the bats a lengthened process, variously shaped, and evidently of considerable importance in the physiology of the organ with which it is connected. It is the tragus to which Gilbert White refers in the text as offering within the ear somewhat of a peculiar structure and as its form, as well the form of the other cutaneous appendages of the bats, is of considerable importance in the distinguishing of these animals from each other; and as, moreover, the distinction of the several kinds of bats is highly desirable, in order to guide us to a more definite knowledge of these imperfectly understood animals, and especially of the habits peculiar to each, it may be well to refer to them as indicating, in most instances, specific characters for the British bats.

It is worthy of remark, however, before commencing this enumeration, that at the time when White first wrote to Pennant on this subject, he knew but two indigenous kinds: the long-eared and that which he regarded as the short-eared: these, in fact, being all that were even known to Linnæus as European. White subsequently became acquainted with another; the great bat of the text. Pennant knew and described a fourth, the horse-shoe bat. Many years subsequently elapsed without the addition of another. The four indigenous species known in 1771 have now been increased to at the least fourteen distinct kinds; so great have been the advances that have of late years been made in England in the search after animals and in the discrimination between them.

The presence or absence of a nose-leaf is generally regarded as of primary importance in the subdivision of the insectivorous bats. Of those that possess such an appendage we have in England only two kinds. These are the horse-shoe bats, forming part of the genus Rhinolophus, and readily distinguishable by their size into the greater (the head and body of which are two and a half inches long,) and the less (which does not measure in total length one inch and a half). Neither of these is very generally distributed throughout the country, although in some situations they are not uncommon: they chiefly frequent old houses and caves.

The remaining British bats are destitute of the nose-leaf, and may be distinguished into genera by characters derived from the expansion of the outer ear. In some of them the two ears meet in the middle of the forehead, and are united at their inner margins. Such is the case with the barbastelle, constituting the genus Barbastellus of Mr. Gray, in which the ears are shorter than the head; and the ears are also united on their inner edge in the long-eared bats, Plecotus, GEOFF. in which the external ear is so largely and disproportionately developed as almost to equal in

[Amphimalla solstitialis, LATR.]

evolutions and quick turns of the swallow genus. But the circumstance that pleased me most was, that I saw

length the entire body and head. The common long-eared bat, Plecotus auritus, GEOFF. is frequent in the vicinity of houses: the expansion of its wings is fully ten inches. A second long-eared bat, which has been suspected to be the young of the former, has been described by the Rev. L. Jenyns as differing from it in many particulars, and especially in the comparative shortness of its fingers, whence he has called it brevimanus: the expansion of its wings is less than seven inches. Of this latter the only individual that has yet occurred was taken from a tree.

All the other bats that have yet been captured in England have their ears distinct from each other, and belong to the genus Vespertilio, which is still an extensive one, notwithstanding the numerous dismemberments to which it has been subjected. Of these some have the ears as long as, or slightly longer than, the head: such are the Vesp. Murinus, DESM. and Vesp. Bechsteinii, LEISL., in which the tragus is about half the length of the auricle, is somewhat expanded on its outer side just above its base, and terminates in a point, the latter species being most readily distinguishable by its exceedingly slender thumb; and the Vesp. Nattereri, KUHL, in which the tragus is linear, and full two-thirds of the length of the auricle. Others, and these the more numerous, have the auricle not so long as the head. In Vesp. mystacinus, LEISL., the tragus is half as long as the auricle, and is lanceolate: in Vesp. emarginatus, GEOFF., the tragus is also half the length of the somewhat lengthened ear, but is subulate: in Vesp. pygmæus, LEACH, the tragus is of the same comparative length as in the two preceding, and is subulate; the species being distinguished (if, indeed, it be a species and not the young of some other, perhaps of the Vesp. Serotinus) by its very diminutive size, the expansion of its wings being scarcely more than five inches: in Vesp. Serotinus, GMEL., the tragus is also subulate, but is not half the length of the ear: in Vesp. discolor, NATT., the tragus is scarcely one-third the length of the ear, and of almost equal breadth throughout: in the pipistrelle, Vesp. Pipistrellus, GMEL., which is the bat of most frequent occurrence in England, (where, on account of its diminutive size as compared with the noctule, it is often called the mouse-bat,) the tragus is half the length of the ear, and is terminated by a rounded head; the expansion of its wings is rather more than eight inches: in the remaining two species, which are nearly of a uniform chestnut colour both above and below, the tragus has almost the same form as in the last, and in the Vesp. Leisleri, KUHL., is scarcely smaller than in the pipistrelle; while in the noctule, Vesp. Noctula, GMEL, it is much reduced in size, being little more than one quarter of the length of the ear, and consists of a rather broad base, becoming expanded towards the tip, especially on the outer side, so widely as to form a head about twice the breadth of the stem that supports it. The noctule is the largest of the English bats, except the rare Vesp. Murinus, its wings extending, when expanded, to the width of fourteen inches: it occurs more frequently than any of the others, with the exception of the pipistrelle (erroneously named Vesp. Murinus by all

it distinctly, more than once, put out its short leg while on the wing, and, by a bend of the head, deliver somewhat into its mouth. If it takes any part of its prey with its foot, as I have now the greatest reason to suppose it does these chafers, I no longer wonder at the use of its middle toe, which is curiously furnished with a serrated claw.

British writers until very recently) and of the long-eared bat. A not unfrequent name for it, indicative of its superiority of size over the pipistrelle, is the rat-bat.

By this enumeration of the indigenous species some idea will have been obtained of the variations in form and developement of the curious structure within the ear referred to by the author, as they occur in the genus Vespertilio, to an extent so great as almost to afford characters for the distinction of every species. In Plecotus the tragus is also developed to an extent proportioned to the exceeding amplitude of the ears themselves. In Barbastellus it also exists in a marked degree. In the horse-shoe bats no such appendage is present; although in many exotic genera the additional leaflet of the ear coexists with that which is superadded to the nose.-E. T. B.

tember the twenty-second, they rendezvoused in a neighbour's walnut tree, where it seemed probable they had taken up their lodging for the night. At the dawn of the day, which was foggy, they rose all together in infinite numbers, occasioning such a rushing from the strokes of their wings against the hazy air, as might be heard to a considerable distance: since that no flock has appeared, only a few stragglers.

Some swifts stayed late, till the twenty-second of August-a rare instance! for they usually withdraw within the first week 2.

On September the twenty-fourth three or four ringousels appeared in my fields for the first time this season: how punctual are these visitors in their autumnal and spring migrations!

DEAR SIR,

LETTER XXXVIII.

TO THE SAME.

SELBORNE, March 15, 1773.

By my journal for last autumn it appears that the house martins bred very late, and stayed very late in these parts; for, on the first of October, I saw young martins in their nest nearly fledged; and again, on the twenty-first of October, we had, at the next house, a nest full of young martins just ready to fly; and the old ones were hawking for insects with great alertness. The next morning the brood forsook their nest, and were flying round the village. From this day I never saw one of the swallow kind till November the third; when twenty, or perhaps thirty, house martins were playing all day long by the side of the hanging wood, and over my fields. Did these small weak birds, some of which were nestlings twelve days ago, shift their

2 See Letter LII. to Mr. Barrington.

quarters at this late season of the year to the other side of the northern tropic? Or rather, is it not more probable that the next church, ruin, chalk cliff, steep covert, or perhaps sandbank, lake or pool (as a more northern naturalist would say), may become their hybernaculum, and afford them a ready and obvious retreat?

We now begin to expect our vernal migration of ring-ousels every week. Persons worthy of credit assure me that ring-ousels were seen at Christmas, 1770, in the forest of Bere, on the southern verge of this county. Hence we may conclude that their migrations are only internal, and not extended to the continent southward, if they do at first come at all from the northern parts of this island only, and not from the north of Europe. Come from whence they will, it is plain, from the fearless disregard that they show for men or guns, that they have been little accustomed to places of much resort. Navigators mention, that, in the Isle of Ascension, and other such desolate districts, birds are so little acquainted with the human form that they settle on men's shoulders; and have no more dread of a sailor than they would have of a goat that was grazing. A young man at Lewes, in Sussex, assured me that about seven years ago ring-ousels abounded so about that town in the autumn, that he killed sixteen himself in one afternoon: he added further, that some had appeared since in every autumn; but he could not find that any had been observed before the season in which he shot so many. I myself have found these birds in little parties in the autumn cantoned all along the Sussex downs, wherever there were shrubs and bushes, from Chichester to Lewes; particularly in the autumn of 1770.

I am, &c.

M