it had been killed some days, and the eyes were sunk, I could make no good observation on the colour of the pupils and the irides'.

The most unusual birds I ever observed in these parts were a pair of hoopoes (Upupa), which came

several years ago in the summer, and frequented an ornamented piece of ground, which joins to my garden, for some weeks. They used to march about in a stately manner, feeding in the walks, many times in the day; and seemed disposed to breed in my outlet; but were frighted and persecuted by idle boys, who would never let them be at rest 2.

The irides of all the British species of true falcons are brown.W. Y.

2 But few instances have been recorded of the breeding in England of

Three gros-beaks (Loxia Coccothraustes) appeared some years ago in my fields, in the winter; one of which I shot: since that, now and then, one is occasionally seen in the same dead season.

A cross-bill (Loxia curvirostra) was killed last year in this neighbourhood *.

that rare and occasional visitant, the hoopoe. The one mentioned in the text is the earliest promise of an attempt at breeding here that I am aware of. It is referred to by both Pennant and Montagu.-E. T. B. 3 [Coccothraustes vulgaris, FLEM.]

The most curious account of the cross-bill was published by Dr. Townson, who kept them tame. See his Tracts on Natural History, p. 116.-MITFORD.

My friend Mr. Yarrell has published, in the fourth volume of the Zoological Journal, an excellent and detailed anatomy of the muscles by which the singular beak and tongue of the cross-bill are made to serve the peculiar purposes for which they are designed. The most powerful muscles are those which are devoted to the laterally separating from each other of the points of the crossed jaws; an apparent deformity in the structure of the bird, but in reality a modification of the usual adjustment of the organs essential to the special wants of the cross-bill. "The great pine forests," says Mr. Townson, "such as the Hartz in Germany, are the natural places of residence of the cross-beaks, and the seed of the cones of those trees their food; and it is to pull out the seeds from between the squamæ, or scales, of the cones, that this structure is given them. Their mode of operation is thus: they first fix themselves across the cone, then bring the points of the maxillæ from their crossed or lateral position to be immediately over each other. In this reduced compass, they insinuate their beaks between the scales; and then opening them, not in the usual manner, but by drawing the inferior maxilla sideways, force open the scales or squamæ."

"At this stage of the proceeding," continues Mr. Yarrell, "the aid of the tongue becomes necessary, and this organ is no less admirably adapted for the service required. The bone of the tongue has articulated to its anterior extremity an additional portion, formed partly of bone with a horny covering; narrow in shape, about three-eighths of an inch in length, extending downwards and forwards, with its sides curved upwards, and its distant extremity shaped like a scoop, somewhat pointed, and thin on the edges." Mr. Yarrell describes with greater detail this superadded and distinct portion of the tongue, and the muscles by which it is moved, and their action; and then proceeds: "While, therefore, the points of the beak press the shell from the body of the cone, the tongue, brought forward by its own muscle (the genio-hyoideus), is enabled by the additional muscles described, to direct and insert its cutting scoop underneath the seed, and the food thus dislodged is conveyed to the mouth and it will be seen by a reference to the first figure, that when the mandibles are separated laterally in this operation, the bird has an

Our streams, which are small, and rise only at the end of the village, yield nothing but the bull's head or miller's thumb (Gobius fluviatilis capitatus 5), the trout (Trutta fluviatilis), the eel (Anguilla), the lampern

uninterrupted view of the seed in the cavity, with the eye on that side to which the under mandible is curved."

The lateral power of the beak of the cross-bill has called forth expressions of astonishment from all who have witnessed its effects. Mr. Townson gives some curious instances of them; and a marked evidence of the muscular strength connected with that organ was afforded by a bird kept by Mr. Morgan, which Mr. Yarrell states to have broken off the point of its beak by repeated efforts to draw a flat-headed nail that confined some strong network: it persevered nevertheless, and was eventually successful. A principal occupation with Mr. Morgan's birds was the twisting out of the ends of the wires of their prison, which they accomplished with equal ease and dexterity: but their repeated success in this operation occasioned the destruction of so many cages that sentence of banishment was at length necessarily passed on those mischievous little beings, whose unceasing delight it seemed to be to disunite all joined substances that were placed within the reach of their bills.-E. T. B.

This and the succeeding names of fishes are derived from Ray's Synopsis Avium et Piscium. The use of Ray's names in this department of zoology, rather than of those of Linnæus, would lead to the suspicion that the author was acquainted with the works of the Swedish master of natural history, through the medium only of the productions of Pennant. At the date of this Letter, the first, or folio, edition of the British Zoology had alone made its appearance; the first two volumes of the second edition, in quarto and octavo, were in preparation: but these extended no farther than the mammals and birds of Britain. The third volume of the second edition of the British Zoology, in which the fishes were for the first time enumerated, was not published till 1769. The information in the text was no doubt communicated in answer to queries having for their object the improvement of Pennant's forthcoming work.

The fish here alluded to is the Cottus Gobio, LINN.-E. T. B. 6 [Salmo Fario, LINN.]

7 In the absence of some definite character the fish here alluded to cannot be safely referred to any of those species of eels, which a more correct acquaintance with them has rendered it necessary for modern ichthyologists to distinguish in the British rivers. It is to the acuteness of Mr. Yarrell that we are originally indebted for most of our information on this subject, which has been partly communicated through the medium of the Zoological Society, and partly in other detached notices; and more recently, in a defined and systematic form, in the Rev. L. Jenyns's Manual of British Vertebrated Animals. Before this volume is published figures and descriptions of them, by Mr. Yarrell himself, will have appeared in his excellent work on British Fishes.

E

(Lampetra parva et fluviatilis), and the stickle-back (Pisciculus aculeatus).

To enable the reader to distinguish between them, their specific differences may be thus noted.

In the sharp-nosed eel, Anguilla acutirostris, YARR., the snout is acute, and compressed at the sides; the gape does not extend farther back than the middle of the eye; and about one-third of the entire length of the fish is situated in front of the commencement of the dorsal fin, and between one-eighth and one-ninth before the pectorals. This species is common throughout the country, and attains a considerable size; measuring two, three, or four feet in length, and sometimes more.

In the broad-nosed eel, Ang. latirostris, YARR., the snout is broad and rounded; the gape extends as far backwards as the hinder edge of the orbit; and more than one-third of the entire length of the fish is in front of the dorsal, and one-seventh in front of the pectoral fins. It rarely exceeds two feet in length; and appears to be almost equally common with the preceding.

In the snig eel, Ang. mediorostris, YARR., the snout is rather long and moderately broad; the gape does not extend quite so far back as the posterior edge of the orbit; there is rather less than one-third of the entire length of the fish before the dorsal, and between one-seventh and one-eighth before the pectoral fins.

Mr. Yarrell's specimens of the last were obtained from the river Avon. It appears not to acquire so large a size as either of the others; seldom exceeding half a pound in weight: while the broad-nosed eel has been known to weigh five pounds, and the sharp-nosed has even acquired the enormous weight of twenty-eight pounds.

The more extensively these characters are tested in different localities, the more assured will be our knowledge of the species of eels, of their distribution, and of their habits: all subjects of considerable interest.— E. T. B.

8 [Ammocætes branchialis, DUM.]

9 On the stickle-back of the text a remark must be made, similar to that which was elicited by the eel. Where, in the days of Gilbert White, only one species was believed to exist, it is now known that there are several. Cuvier clearly distinguished three, and indicated others, that had previously been confounded under the common name of Gasterosteus aculeatus; and Mr. Yarrell subsequently made known the fact that these several kinds were found in England also. In his History of British Fishes he has given figures and descriptions of four different kinds of three-spined stickle-backs, as well as of a four-spined species. The latter was obtained from the neighbourhood of Edinburgh, and is regarded as altogether new; it is the Gast. spinulosus of Messrs. Yarrell and Jenyns.

It is easy to distinguish between the several kinds of three-spined stickle-backs, if attention be paid to the manner in which their sides are covered. If the bony plates which spread away from the lateral line

We are twenty miles from the sea, and almost as many from a great river, and therefore see but little of seabirds. As to wild fowls, we have a few teams of ducks bred in the moors where the snipes breed; and multitudes of widgeons and teals in hard weather frequent our lakes in the forest.

Having some acquaintance with a tame brown owl, I find that it casts up the fur of mice, and the feathers of birds, in pellets, after the manner of hawks: when full, like a dog, it hides what it cannot eat.

The young of the barn-owl are not easily raised, as they want a constant supply of fresh mice: whereas the young of the brown owl will eat indiscriminately all that is brought; snails, rats, kittens, puppies, magpies, and any kind of carrion or offal.

The house-martins have eggs still, and squab-young. The last swift I observed was about the twenty-first of August; it was a straggler.

Red-starts, fly-catchers, white-throats, and Reguli non cristati, still appear; but I have seen no blackcaps lately.

I forgot to mention that I once saw, in Christ Church college quadrangle in Oxford, on a very sunny warm morning, a house-martin flying about, and settling on the parapets, so late as the twentieth of November.

both above and below it, for the protection of the otherwise naked sides of the fish, are extended along the whole of the side as far as the caudal fin, it is the rough-tailed stickle-back, Gast. trachurus, Cuv. and VAL.: if these bony plates do not extend farther backwards than the line of the vent, it is the half-armed stickle-back, Gast. semiarmatus, Cuv. and VAL.: if the lateral plates reach no farther backwards than the end of the pectoral fin, it is either the smooth-tailed stickle-back, Gast. leiurus, Cuv. and VAL., with the dorsal spines or stickles about one-sixth of the height of the body; or the short-spined stickle-back, Gast. brachycentrus, Cuv. and VAL., with the dorsal spines not more than one-twelfth of the height of the body. The latter is the largest of the stickle-backs found in the United Kingdom: it occurs in the north of Ireland.

Including the ten-spined species, six distinct kinds of stickle-backs are now known to inhabit the fresh waters of these islands; and there are few situations in which four of them, or at the least three, may not be caught in the ponds and rivers.-E. T. B.