menon be solved by attributing it to the presence of the male glowworm? A friend of mine some years ago related to me the astonishment he once felt, in riding across a moor in Somersetshire, in seeing a light flitting about his horse's bridle, and advancing as he advanced for a considerable distance. About a month ago, one of my domestics observed a soft and beautiful light (flame as he conceived) flitting in a field adjoining my residence. I have no doubt it proceeded from a male glowworm, and I have this year traced the Lampyris noctiluca, both male and female, through all its stages. In the larva state, both male and female emit their light from two points near the extremity of the end of the body; in the nymph state the light is also, although more feebly, displayed. On emerging to its perfect state, the female emitted light from eleven points, but most brilliantly from two, and the male from two only. Within the last six weeks there has scarcely been an evening when my study windows have been open, in which a male glowworm (and sometimes three or four in the course of the evening) has not flown in; all of them exhibiting their light, either voluntarily or on being excited by meddling with them. I had two or three female glowworms on a turf under a receiver in one corner of the room, and it is not improbable that sexual instinct was the occasion of my being so numerously visited. The male glowworm I have observed to live from two to four days after introduction to the female; and the latter to survive ten days or a fortnight, having laid a vast number of eggs. - Albert. July 12. 1832.

Of Winds. (Vol. II. p. 175.) — Mr. Main, speaking of the trade winds blowing constantly from east to west, says: "This is caused by the cooler air of evening pressing westward upon the heated air of midday; in other words, the lower temperature of the air in the place to the eastward of the sun causes it to press westward upon the rarefied air of the place over which he is vertical." It may be sufficient here to observe, that, if this were granted, it might produce an easterly wind in the evening; but it would also produce one from the west in the morning. In fact, however, the temperature of the surface of the sea, in the places Mr. Main mentions, is not sufficiently affected by the midday sun to produce any such consequences: it is, indeed, scarcely perceptibly raised. The generally received and probably correct explanation is, that the currents of cold air from the poles, spoken of by Mr. Main in his concluding paragraph, reach the equatorial regions without having entirely acquired the equatorial whirling motion. A Subscriber. Vale of Alford, Sept. 28. 1832.

ART. II. Queries and Answers.

IN twin-born Calves, both are sometimes fertile.-Sir, In answer to the query of U. of Cambridge (p. 396, 397.), " In twin-born calves, is one of the two invariably sterile? And, if the two be male and female, is the sterile one invariably the female?" I beg to state that the female is not invariably sterile, although such an idea is very prevalent. Joseph Holroyd, Esq., of Withers, near Leeds, told me, in July, 1826, when we were conversing upon this subject, that he had a cow which calved twins, a bull calf and a cow calf. As popular opinion was against the cow calf breeding, it being considered a free martin, as described by John Hunter, Mr. Holroyd was determined to make an experiment of them, and reared them together. They copulated, and in due time the heifer brought forth a bull calf, and she regularly had calves for six or seven years afterwards.

I would refer your correspondent to John Hunter's Observations on certain Parts of the Animal Economy, 4to, 2d edition, p. 55., where he will find his paper on the free martin, originally published, I believe, in the Philosophical Transactions; and at p. 60. of the same paper, J. Hunter candidly states:-"Although what I have advanced with respect to the production of free martins be in general true, yet, by the assistance of Benj. Wray, Esq., of Denham, near Uxbridge, who knew my anxiety to ascertain this point, I was lately furnished with an instance which proves that it does not invariably hold good." He then goes on to state the case, and the dissection of the animal:-" I have heard of other twin cows breeding; but as I cannot call to mind the names of the individuals who communicated the circumstances to me, I have only mentioned one of undoubted authority. Yours, &c. Richard Moulson, M.D. Halifax, Yorkshire, May 30. 1832.

Moles do swim of choice. (p. 78. 296.) — J. D., at p. 78. 296., asks if moles swim of choice? I answer, yes. Last summer and autumn I visited a river at the bottom of the Botanic Garden, several times very early in the morning and late in the evening, for the purpose of procuring a specimen to preserve of the kingfisher (Alcedo I'spida L.), which is frequently to be met with here. One morning as I sat very quietly, I observed a mole come out of an osier holt, and run across a grass path and take to the water; when it was about half across the river, I ran to the edge of the water, and the mole then made a perceptible attempt to dive, but merely immersed his nose in the water for half a minute, and rapidly gained the shore, and soon disappeared in a hole of the bank.

A few mornings after, I saw it again take to the water, as before; but as I remained perfectly still, I observed its unrestrained actions. It was nearly four minutes in swimming six yards, and appeared as if it rather enjoyed its morning's bathing. I mentioned this to an old molecatcher, as I thought it rather singular, who replied, "I've seen 'em swim across rivers of a devil and all of a width." Yours, &c. - H. Turner. Bury St. Edmunds, May 9. 1832.

Reply to T. K's Queries (p. 397.) on the Windpipe, Plumage, and Weight of the Dun Diver. - Sir, In reply to the queries of T. K., p. 397., I send the following remarks, accompanied by drawings of the tracheas of our three British species of Mérgus. Fig. 126. represents the trachea, with

126

128

127

its bronchial tubes, of Mérgus Merganser L. (the goosander), the female and young of which is the common dun diver: the sex may easily be distinguished, as, like the duck tribe, it is the male only that has any enlargement of the trachea, or any labyrinth at the end of it. The young male may in general be distinguished at sight from the female by its larger head and neck; the female is also always of the

same colour, with precisely the same markings; whereas the young male, though sometimes exactly coloured and marked like the female, has very frequently wandering white feathers, clearly indicating an approach to a change of plumage. I have had repeated opportunities of examining the tracheas of the young males, and have always found them to correspond exactly with the mature bird, and resembling fig. 126. The weight of this bird, according to Montagu, is four pounds. Fig. 128. represents the trachea of Mérgus serràtor L. (the red-breasted goosander), the females and young males are also dun divers, but of a smaller size, weighing only about two pounds; but though only about half the size of Mergus Merganser, its trachea is nearly as large, and has but one enlargement, whilst the labyrinth has two enlargements, instead of one, as in Mérgus Merganser. The female and young are of a duller and heavier colour than Mérgus Merganser, the wing spot is divided by a band, and the neck and head are proportionally much smaller. This, I have no doubt, is the bird of T. K., which he describes, and requests the name of, in p. 397. Fig. 127. represents the trachea of Mérgus albéllus L. (the smew). Rennie, in his edition of Montagu, says, "This is by far the most plentiful species that frequents our coasts, and fresh waters, &c., in the winter." I have myself obtained more of the Mérgus Merganser than of this species. I have never seen a young male of this species marked exactly like the female: but I have had them very nearly alike, and so near as fully to convince me that the young males of all the three species undergo the same change of plumage, from that of the female to the adult male; and that we have, in fact, only three species. The figures are all much reduced. Thomas Allis. York, 27th of the 6th month (June), 1832.

An English Work descriptive of the Genera and Species of British Insects. (p. 686.) — In answer to Tyro (p. 686.), I can only say there is no such work at present published. There is a slight chance (very slight, I hope) of such a work; but no man of honourable feelings will think of buying it, should it be allowed to appear. Professor Rennie has, as most of your readers know, pirated the whole of Mr. Stephens's Haustellata, as far as published, and appended thereto a bungling translation of the last parts of the Lepidoptera Britannica; but, alas! the sale of his Conspectus (a name chosen by the professor from his dislike of using Latin words) has been stopped by an injunction from the Court of Chancery; and the professor's books will, I trust, rot on the bookseller's shelves.-E. Doubleday. Epping, Sept. 29. 1832.