102 



THE EDINBURGH JOURNAL OF NATURAL HISTORY, 



unnecessary to speak at present, as the species in the plate, which represent three of 

 these sections, have been referred to the singh^ genus Hirundo. These birds are 

 extensively distributed, some species occurring in all the warm and temperate parts 

 of the globe, or, during the summer, extending their migrations to the confines of 

 the frozen regions. Those represented in the plate are all natives of America. 



Fig. 1. The Barn S\vai.lo\\ (Hirundo rufa.) Male.— This species so closely 

 resembles the JI. rustica of Europe, that some ornithologists have considered it 

 absolutely the same. It is about seven inches in length, with long pointed wings, 

 and a very deeply forked tail; the forehead and throat reddish-brown, a dusky bar 

 across the fore neck, the upper parts glossy bluish black, and the tail-feathers with a 

 ■white spot on the inner web. It visits all parts of the United States in the end of 

 spring, nestles in the same manner as our Chimney Swallow, lays five white eggs 

 spotted with reddish-brown, and generally rears two broods in the season. 



Fig. 2. The Barn Swallow. Female. — The female has the tail less elon- 

 gated, the upper parts tinged with green, the rufous colour on the throat and fore- 

 head paler. 



Fig. 3. The Bank Swallow (H. riparia.) — This species, which is much 

 smaller than the last, and of a greyish-brown colour on the upper parts, is common 

 to both continents, its habits in America being precisely similar to those which it 

 exhibits with us. It receives its specific name from its burrowing in sandy banks. 



Fig. 4. The White-bellied Swallow (H. hicolor.) — The upper parts are of 

 a glossy greenish-blue, the lower white. It has been ascertained by Mr Audubon to 

 winter in Louisiana, and in summer to extend over all parts of the United States. 



Fig. 5. The Cuff Swallow (if. /M^ra.) — This species, which is named from 

 its habit of building on the face of rocks, is more variegated in its colours than 

 the preceding, and has the tail abrupt or truncate. It inhabits the southern and 

 western parts of the United States, from whence it returns southward in August. 



Fig. 6. The White-collared Swallow (11. albicollls,) — Of this species little 

 seems to be known. It is of a uniform blackish colour, with a band of white across 

 the hind part of the neck, and a patch of the same colour on, the fore neck ; and is said 

 to inhabit Brazil. 



Ravages of Field Mice. — The following interesting account of the destructive 

 effects of Field Mice is extracted from Mr Jesse's Gleanings : — " An extraordinary 

 instance of the rapid increase of Mice, and of the injury they sometimes do, occurred 

 a few years ago in the new plantations made by order of the crown in Dean Forest, 

 Glocestershire, and in the New Forest, Hampshire. Soon after the formation of 

 these plantations, a sudden and rapid increase of Mice took place in them, which 

 threatened destruction to the whole of the young plants. Vast numbers of these were 

 killed ; the Mice having eaten through the roots of five-year-old oaks and chestnuts, gene- 

 rally just below the surface of the ground. Hollies also, which wore five or six feet 

 high, were barked round the bottom ; and in some instances the Mice had crawled 

 up the tree, and were seen feeding on the bark of the upper branches. In the re- 

 port made to government on the subject, it appeared that the roots had been eaten 

 through wherever they obstructed the runs of the Mice. Various plans were de- 

 vised for their destruction; traps were set, poison laid, and cats turned out; but 

 nothing appeared to lessen their number. It was at last suggested, that if holes 

 were dug, into which the Mice might be enticed to fall, their destruction might be 

 effected. Holes, therefore, were made, about twenty yards asunder, in some of the 

 Dean Forest plantations, being about twelve in each acre of ground. These holes were 

 from eighteen to twenty inches in depth, and two feet one way by one and a half the 

 other ; and they were much wider at the bottom than at tVie top, being excavated or 

 hollowed under, so that the animals when once in could not easily get out attain. 

 In these holes at least thirty thousand were caught in the course of three or 

 four months, that number having been counted out and paid for by the proper 

 officers of the forest. It was, however, calculated that a much greater number 

 than these were taken out of the holes, after being caught, by Stoats, Weasels, 

 Kites, Hawks, and Owls ; and also by Crows, Magpies, Jays, &c. The Cats, also, 

 which had been turned out, resorted to these to feed upon the Mice ; and, in one 

 instance, a Dog was seen greedily eating them. In addition to the quantity above 

 mentioned, a great many Mice were destroyed in traps, by poison, and by animals 

 and birds of prey ; so that in Dean Forest alone, the number of those which were 

 killed in various ways could not be calculated at much less than one hundred thou- 

 sand. In the New Forest, from the weekly reports of the deputy-surveyor of the 

 forest, about the same number were destroyed, allowing the same calculation for 

 those eaten by vermin, &c. ; in addition to which, it should be mentioned, that these 

 Mice were found to eat each other when their food fell short in winter. Putting 

 these circumstances together, the total destruction of Mice in the two forests in 

 question would probably amount to more than two hundred thousand." 



Matrimonial Union between a Blackbird and a Thrush. — We are in- 

 debted to Mr Weir of Boghead for the following notice : — That birds in a state of 

 confinement should be induced, by the solicitations of love, to form matrimonial alli- 

 ances with other species of the same genus, or such as resemble them most closely in 

 size and habits, when they ha^e not an opportunity of making a choice, is not wonder- 

 tul ; but that they should do so when left at liberty, is of very rare occurrence. Mr 

 Russell of Blosside, my next neighbouring proprietor, and his brother, informed me, 

 that they were surprised at the attention which a male Blackbird paid to a female 

 Thrush about the end of the winter of 1836. They were always in company, and 

 fed together. As the spring approached, their attachment appeared more decided, 

 and they carried on a course of regular flirtation, which ended in matrimony. After 

 a good deal of consultation, they at length determined to build their nest in a bush 

 of heath which hung over what is here called a " farret brae." They had four 

 young ones before the nest was discovered, so cunningly had they concealed it. 



When they were about half fledged, they were unfortunately carried off by some 

 boys, notwithstanding all the care that had been taken to preserve them. 



Snowy Owl shot in England. — On the 13th of February last, a fine male 



Snowy Owl was shot three miles below Selby-on^the-Mupr, where it liad been ob- 



served by the miller at a mill adjoining, for a day or two previous. The moor is well I 

 stocked with Rabbits, and the Owl was most probably preying upon them. It ap- 

 peared very shy, and when pinioned by the shot was extremely fierce. It was ulti- 

 mately got into a sac and killed by pressure, when it came into the possession of A. 

 Clapham, Esq. of Potternewton, near Leeds. — H. Denny ^ in the Magazine of Zoo- _ 

 logy and Botany. HI 



Attachment of the Lark to its Young.. — Some mowers shaved off the upper ■ 

 part of the nest of a Sky Lark without injuring the female, which was sitting on its 

 young ; still she did not fly away, and the mowers levelled the grass all round with- 

 out her taking further notice of their proceedings. A young friend of mine, son of 

 the owner of the crop, witnessed all this, and about an hour afterwards went to see 

 if she was safe, when, to his great surprise, he found that she had actually construct- 

 ed a dome of dry grass over the nest during the interval, leaving an aperture on one 

 side for ingress and egress. My friend immediately hastened to inform me of the 

 circumstance, and I was about to follow him to the spot, but, on his return, he 

 found that some ruffian had, in the meantime, torn open the nest, and made off 

 with the young ones. How disheartening it is for the Naturalist to be so continual- 

 ly annoyed by these callous bird-nesters! I was in hopes, when the brood had left 

 the nest, to have preserved the latter as a most interesting specimen ; but, alas ! all 

 is, as usual, frustrated. I should add, that the intention of the parents was, ob- 

 viously, to have preserved their young from the scorching heat of the sun. — Mr 

 Blytkj in The Naturalist. 



BOTANY. 



GENERAL REVIEW OF THE VEGETABLE KINGDOM NO. V 



Vegetation, in ascending above the level of the sea, undergoes modifications ana- 

 logous to those which attend its progress from the line to either pole, with this dis- 

 tinction, that in the last case the phenomena succeed by almost imperceptible grada- 

 tions, while they crowd upon and follow each other in rapid succession on the ascent 

 of mountains. The height of 4000 or 5000 yards in the hottest parts of the globe 

 produces changes as distinct as the 2000 leagues, or more, which lie between the 

 Equator and the polar regions. The three causes of the influence of which we have 

 just spoken, all reappear within this space, viz. a diminution of heat ; dryness of air ; 

 and protracted duration of light. To these we must add two others, a decrease of 

 depth in the volume of the air, and a scarcity of those substances which abound in 

 carbon, and are produced by the decomposition of organic bodies. 



The higher we ascend, the shallower the upper stratum of air becomes ; whence the 

 excessive cold at great heights ; for it is the action of the atmosphere upon the rays 

 of light which extracts the caloric from them, and we know that the extraction of 

 caloric diminishes in proportion as the mass of air traversed by the rays is shallower ; 

 but, on the other hand, the light is purer and more active, just as if caloric was really 

 a simple transmutation of light, as some naturalists have conceived it to be. 



The weight of the atmosphere, which at the level of the sea supports a column of 

 mercury 28 inches high, diminishes as we ascend; so that at the elevation of 6000 

 yards it will only support a column of 13 inches and some lines high. A consequence 

 of this fact is, that the vaporisation of fluids takes place on high mountains at a very 

 low degree of heat. Notwithstanding this, however, the decrease of heat is so great, 

 that the ambient air is very slightly impregnated with moisture. 



It is true that heights have not the long days of the polar regions; but they re- 

 ceive the rays of the sun earher than the plains, and are quitted later by them, so that 

 their nights are shorter than in levels. 



In fine, substances containing carbon, the wrecks of organised bodies, are rare on 

 mountains, the rains as well as the waters of the springs dissolving them, and carry- 

 ing them away as they run off into the valleys. 



It cannot be doubted, but these causes united must act powerfully upon vegetation. 

 The slightest degree of heat will cause the plants on mountains to transpire copious- 

 ly ; the severity of the cold, the dryness of the atmosphere, the shortness of the 

 nights, the scarcity of carbon, will impede the enlargement of their leaves, and the 

 growth of their stems ; the strength of the light, and the protracted duration of the 

 day, will accelerate the induration of all the parts of their frame. 



The course of vegetation on mountains had not escaped the penetration of Tourne- 

 fort. At the foot of Mount Ararat he had observed the plants which grow in Arme- 

 nia ; a little higher, those of Italy and France ; above, those of Sweden ; and upon 

 the summits, those of Lapland. Observations of the same kind had been subsequent- 

 ly made on Mount Caucasus, the Alps, the Pyrenees, and other mountains of the old 

 Continent. Every botanist had learned that many of the Alpine plants, that is to 

 say, plants which grow on the various high lands of Europe and Asia, are likewise 

 met with at Spitsbergen, in Nova Zembla, Lapland, and Kamschatka. Swartz had 

 discovered on the mountains of Jamaica, under a still hotter sky, if not plants exactly 

 of the same species with those of our Alpine Phcenogaraous ones, at least some that 

 were analogous to them ; and a great many of the Cryptogamous species precisely 

 the same as our own : For example, Fiuiaria hygrometrica, Bryum serpylUfoliunt 

 and cespititium. Sphagnum palustre, Dicranum glaucum, &c. Linnaeus, in his 

 own way, hsd summed up these facts in an axiom. ** The different kinds of plants,' 

 says he, '* show by their stations the perpendicular height of the earth. Yet it 

 was not till lately that any exact survey had been taken of this interesting department 

 of botanical geography. 



The first connected series of researches made with the direct intention of ascer- 

 taining the progressive succession of plants on mountains, was instituted by JI. Ra- 

 mond. That celebrated individual devoted ten years to the investigation of the 

 entire chain of the Pyrenean mountains ; and studied it not only as a geometrician, 

 natural philosopher, and mineralogist, but also as one of the most skilful of botanists ; 

 he discovered, with the sagacity that distinguishes him, the stations to which the 

 different species of vegetables belong, and the special circumstances which sometimes 

 cause a derangement in the natural order of their succession. We shall here shortly 

 point out some of the results of his observations. 



The Common Oak (^Quercus Rohuf). grows in the plains, on a level with the sea; 



I 



