388 Natural History in Foreign Countries. 



as well as their larvae, were very abundant, and more beautiful than usual: 

 {Mem. de la Sociffle de Phys, et de Hist. Nat. de Geneve.) 



Rock Blocks. — M. von Buch has undertaken to show that the rock 

 blocks, which are scattered over the vicinity of Mount Jura and elsewhere, 

 have been dissevered at once by a violent shock, and that they have not 

 been simply rolled upon an inclined plain, nor carried along by avalanches, 

 nor projected by explosions of gas, as M. de Luc supposed. He finds that 

 the higher blocks of the Jura must have required an impetus of 357 feet to 

 traverse in water alone (dans de I'eau pure), the space between the point 

 of Ornex and the Jura. This is an impetus five times less than that of a 

 cannon ball j and if the water (as it must have been) \vere loaded with sludge, 

 the weight of the blocks would be thence much diminished. He refers lor 

 proof of his theory to the bursting of the Lake De Bagne, which being 

 situated 150 feet above the valley, rushed on with an impetus of 53 feet. 

 Chains of mountains have been elevated upon the fissures made across the 

 secondary deposits which have been rent, raised, and changed, while metals, 

 and oxygenated minerals have been introduced by gas into the formations. 

 All the great Alpine valleys have a suite of lateral ravines, of contempora- 

 neous origin with the mountain chains whose elevation produced the dis- 

 persion of the blocks, the waters having risen, and forming a dSbaelcy 

 descended with the debris through the rents made in the secondary chains. 

 M. von Buch answei*s the objection of De Luc, as to the blocks being found 

 behind the mountains, and not in the ravines between them, by making 

 Mount Sionand Sal^ve genuine buttresses, behind which the blocks would 

 iiaturally be carried. {Bulletin des Sciences.) 



* 



SWEDEN. 



Animal GeograpJiy. — M. Gloger has published a very Interesting paper, 

 giving indications of" the heights at which quadrupeds and birds of various 

 species are found in Sweden, of which the following is an abstract : — 



Quadrupeds. Cervus Capreolus is found up to the limits of the Phius pu- 

 milio ; the (7ervus ^'laphus in regions somewhat lower j the iepus timidus, 

 along with the Cervus Capreolus; the J^'us decumanus and M. musculus, 

 in all parts inhabited by man ; the Hypudae'us amphibius, up to the height of 

 4000 feet ; the Sorex of several species, to a height of 4300 ft. ; the MiistVa 

 vulgaris and M. Erminea upon the most elevated mountains. 



Birds. A'quWa fulva is found in low situations ; Corvus Cornix, below 

 4300 ft. ; Nucifraga brachyrhynchus, in low situations; Sylvia Tlthys in 

 higher places ; S. Phoenicurus,' to 3900 ft. ; S. Trochilus, 4400 ft. ; S. Atrica- 

 pilla,-5700; S. Rubecula, 4000; ikTotacilla alba, and M. sulfurea, 4300; 

 Cinclus aquaticus, 3200 : Accentor modularis, 4600; Accentor alpinus, on 

 the most elevated sununits ; ^lauda arvensis, 4400 ; A. arborea, 200 ; 

 i^ringflla coe'lebs, 4000 ; Loxia curvirostris, 4500 ; ikfotacilla troglodytes, 

 Parus ater, P. cristatus, Sylvia iJegulus, Certhia familiaris, and ^Sitta 

 europae'a, at 3800 ft. ; JUidndo urbica, and Cypselus i4 pus, on the highest 

 summits. »" 



RUSSL\. 



Lignite. — M. Lichfeldt has discovered a mass of fossil wood upon one of 

 the gulphs of the Danube, named Yalpoug, in the lower part of Bessarabia 

 called Boudjak, about fifty versts from the fortress of Ismail, and opposite 

 the town of Belgrade, upon the right bank of the gulf between the villages 

 of Kourtchi and Impoiitsit. This fossil wood may become of great import- 

 ance in that part of Russia, now entirely deprived of forests. 'J'he lignite 

 is found in the form of fissile masses, of a greyish colour, but passing in the 

 lower portions into a deep black. In the upper parts are found quantities 

 of the debris of wood, covered with bark, white, thick, and friable; the. 



