not fond of going near the water, but feed on earth-worms, that are common on sheep-walks and downs. They breed on fallows and lay-fields abounding with gray mossy flints, which much resemble their young in colour; among which they skulk and conceal themselves. They make no nest, but lay their eggs on the bare ground, producing in common but two at a time. There is reason to think their young run soon after they are hatched; and that the old ones do not feed them, but only lead them about at the

time of feeding, which, for the most part, is in the night." Thus far my friend.

In the manners of this bird you see there is something very analogous to the bustard, whom it also somewhat resembles in aspect and make, and in the structure of its feet.

tion is to presume that a portion of the migratory party, in their southern flight in the autumn, hold a northern limit just reaching the Land's End and the Lizard lands (the most southern in the British isles), the corresponding northern migration in the spring just taking the whole number above the southern latitudes of the extreme western counties -ED.

For a long time I have desired my relation to look out for these birds in Andalusia; and now he writes me word that, for the first time, he saw one dead in the market on the 3rd of September.'

When the Edicnemus flies it stretches out its legs straight behind, like a heron.

LETTER XXXIV.

TO THOMAS PENNANT, ESQUIRE.

SELBORNE, March 30, 1771.

HERE is an insect with us, especially on chalky districts, which is very troublesome and teasing all the latter end of the summer, getting into people's skins, especially those of women and children, and raising tumours which itch intolerably. This animal (which we call a harvest bug) is very minute, scarce discernible to the naked eye, of a bright scarlet colour, and of the genus of Acarus. They are to be met with in gardens on kidney beans, or any legumens, but prevail only in the hot months of summer. Warreners, as some have assured me, are much infested by them on chalky downs; where these insects swarm sometimes to so infinite a degree as to discolour their nets, and to give them a reddish cast, while the men are so bitten as to be thrown into fevers.

There is a small long shining fly in these parts very troublesome to the housewife by getting into the chimneys and laying its eggs in the bacon while it is drying. These eggs produce maggots called jumpers, which, harbouring in the gammons and best parts of the hogs, eat down to the

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1 Mr. Howard Saunders, in his "List of the Birds of Southern Spain" (Ibis, 1871, p. 386), includes the stone curlew as common and resident, frequenting dry watercourses, and the most arid plains, where it deposits its eggs."-ED.

bone and make great waste. This fly I suspect to be a variety of the Musca putris of Linnæus. It is to be seen in the summer in farm-kitchens on the bacon-racks, and about the mantlepieces and on the ceilings.

The insect that infests turnips and many crops in the garden (destroying often whole fields while in their seedling leaves) is an animal that wants to be better known. The country people here call it the turnip-fly and black dolphin, but I know it to be one of the Coleoptera; the "Chrysomela oleracea, saltatoria, femoribus posticis crassissimis." very hot summers they abound to an amazing degree, and as you walk in a field or in a garden, make a pattering like rain by jumping on the leaves of the turnips or cabbages.'

In

There is an Estrus, known in these parts to every ploughboy; which, because it is omitted by Linnæus, is also passed over by late writers, and that is the curvicauda of old Mouffet, mentioned by Derham in his " Physico-Theology," p. 250, an insect worthy of remark for depositing its eggs as it flies in so dexterous a manner on the single hairs of the legs and flanks of grass horses. But then Derham is

2

1 On the subject of the Turnip-fly the reader may be referred to the "Letters of Rusticus," pp. 91-108, and to an excellent account published by Mr. Edward Newman in the "Field" of Nov. 20, 1869.

Against the attacks of the black caterpillar, or "black dolphin," as White terms it, no preventive has yet been suggested. The most effectual means of keeping it under is by freely sprinkling the infested fields with lime, and renewing the sprinkling as often as the fine powder may happen to be carried away by the wind. The same process appears also to have been the most successful that has yet been resorted to against the attacks of the ordinary turnip-fly. It is strongly recommended in a report which was published in 1834 by the Doncaster Agricultural Society, as the result of a very extensive correspondence, instituted with the especial view of collecting, from all parts of England, information on a subject of so much importance to the agriculturist.— ED.

2 Gilbert White was mistaken in supposing that Linnæus had overlooked this insect. He described it both in the "Fauna Suecica" and in his "Systema," under the name of Estrus bovis, but the habitats which he assigned to it, namely, the stomach of the horse and the back of kine, show that he confounded together two distinct insects, the maggots of which infest the several situations referred to by him. The maggots of the one, known by the names of wormals or warbles, and

mistaken when he advances that this Estrus is the parent of that wonderful star-tailed maggot which he mentions afterwards; for more modern entomologists have discovered

sometimes by that of bots, are found beneath the skin of cattle: these are the larvæ of the true Estrus bovis, the perfect fly of which was probably unknown to the great Swedish naturalist. The maggots of the other, known, in common with those of some other species, by the name of bots, are found with the larvæ of those other bot-flies in the stomachs of horses. The one whose habits are described by White, may be called the spotted-winged bot-fly.

Mr. Bracy Clark, who has well described the habits of these insects in his "Observations on the Genus Estrus," published in the third volume of the "Linnean Society's Transactions," and subsequently in an "Essay on the Bots of Horses," says: "The female bot-fly approaching a horse on the wing, holds her body nearly upright in the air, and her tail, which is lengthened for the purpose, curved inwards and upwards: in this way she approaches the part where she designs to deposit the egg; and suspending herself for a few seconds before it, suddenly darts upon it, and leaves the egg adhering to the hair: she hardly appears to settle, but merely touches the hair with the egg held out on the projected point of the abdomen. The egg is made to adhere by means of a glutinous liquor secreted with it. She then leaves the horse at a small distance, and prepares a second egg, and, poising herself before the part, deposits it in the same way. The liquor dries, and the egg becomes firmly glued to the hair: this is repeated by various flies, till four or five hundred eggs are sometimes placed on one horse.

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mane.

The inside of the knee is the part on which these flies are most fond of depositing their eggs, and next to this on the side and back part of the shoulder, and less frequently on the extreme ends of the hairs of the But it is a fact worthy of attention, that the fly does not place them promiscuously about the body, but constantly on those parts which are most liable to be licked with the tongue; and the ova therefore are always scrupulously placed within its reach. Whether this be an act of reason or of instinct, it is certainly a very remarkable one." Mr. Bracy Clark suspects, with Dr. Darwin, it cannot be the latter, as that ought to direct the performance of any act in one way only.

The eggs thus deposited are not, in Mr. Bracy Clark's opinion, removed from the hairs by the moisture of the horse's tongue, aided by its roughness, in the act of licking, and thus conveyed to the stomach: but remain, he conceives, attached to the hairs for four or five days until they have become "ripe, after which time the slightest application of warmth and moisture is sufficient to bring forth in an instant the latent larva. At this time, if the tongue of the horse touches the egg, its operculum is thrown open, and a small active worm is produced, which readily adheres to the moist surface of the tongue, and is from thence conveyed into the stomach." For the manner in which the larva affixes

that singular production to be derived from the cgg of the Musca chamæleon: see Geoffroy, t. 17, f. 4.

A full history of noxious insects hurtful in the field, garden, and house, suggesting all the known and likely means of destroying them, would be allowed by the public to be a most useful and important work. What knowledge there is of this sort lies scattered, and wants to be collected; great improvements would soon follow of course. A knowledge of the properties, economy, propagation, and in short, of the life and conversation of these animals, is a necessary step to lead us to some method of preventing their depredations.

As far as I am a judge, nothing would recommend entomology more than some neat plates that should well express the generic distinctions of insects according to Linnæus;

itself in the stomach by means of the two hooks with which it is furnished at its smaller extremity; its mode of growth; its detachment, when fully grown, from the stomach; its passage through the intestines to remain, during its pupa state, in some convenient spot of dung or earth; some anatomical particulars respecting it; and many other facts relating to the fly in its various stages, as well as to other species; the reader is referred to the paper in the "Linnean Society's Transactions," from which the above extracts are taken. Interesting as they are, the explanation of them would extend this note to too great a length, and would carry it altogether away from the point to which it is chiefly directed, the admirable provision adverted to in the text for securing for the bots the only habitation in which they could exist.-ED.

The singular larva of the Stratiomys chamæleon, DE GEER, has been repeatedly figured and described; and the use of the star-like circle of feathered hairs appended to its tail, as a means of suspending that part and the orifice of the respiratory tube in their centre, has been often explained: it is among the most beautiful as well as the most curious contrivances resorted to for such a purpose by ever-varying Nature. The eggs from which these larvæ are produced are affixed by the parent fly to plants living in the water in which the development of the maggot is to take place: those seen by Messrs. Kirby and Spence were "arranged like tiles on a roof, one laid partly over another, on the under side of the leaves of the water-plantain."-ED.

2 Since this observation was penned, the labours of Messrs. Kirby and Spence, Curtis, Newman, and others have gone far to supply the want alluded to, and have placed in the hands of students a store of most valuable and interesting facts on the subject of entomology.-ED.