Natural'Historical Collection* J. 453 



isolated manner, from the bottom of the sea. All the volcanoes in the globe may 

 bjB divided into two classes — central volcanoes, and volcanoes in line ; and these 

 tyQ classes do not differ from one another in composition, or in products. The 

 former always constitute the central point of a great quantity of mouths of effu- 

 sion, almost equally scattered in every direction. If we consider chains of moun- 

 tains as masses which have been elevated upon large clefts by the action of mela- 

 [^ires (black or augitic porphyries,) we shall understand to a certain degree the 

 situation of volcanic mouths. Effused islands with craters of effusion often lay 

 the foundation of the tirst class ; this is probably often the case in the South 

 Seas. 



; Of volcanoes in lines Sir. Elie Beaumont mentions the suite of islands in the 

 Grecian Archipelago from the isthmus of Corinth to the island of Santorin. Such, 

 also, are the volcanoes of the Archipelago of Java, the Straits of Sunda, and the 

 Cordillera of the Andes. 



. In speaking of volcanoes we are always led to speak of trachytes and basalts. 

 Volcanic products, trachytes, and basalts are three neighbouring groups, but 

 distinct, if non-stratified rocks. Some lavas, as those of the island of Lancerota, 

 might be taken for basalts. Basalts are sometimes as intimately connected with 

 qonglomerate as trap rocks with the tufas, which are inserted in their masses. 



Basalts, like trap rocks, appear to have been raised to the surface of the earth 

 by irregular openings, or by clefts in the solid crust, accompanied by considerable 

 quantities of incoherent fragments, which have remained interjected, under the 

 form of conglomerates, between the different masses, when these are stretched over 

 the pre-existing soil. 



Basalts of a more recent origin have often been cast up through the mineral 

 crust of the globe, in points previously marked out, in the disposition of the ele- 

 ments of our globe, to present craters of effusion, in the midst of which cones of 

 true volcanoes of eruption would show themselves. 



Trachytic masses, accompanied by their conglomerates, in producing them- 

 selves under the form of cones, of domes, or of rounded masses, more or less irre- 

 gular, appear to have prepared the plan for volcanic centres. 



We shall give the geological result of these researches at a future opportunity. 



Fossil Animals of Russia — Mr. Fischer proves, by his notices on the fossil 

 animals of Russia, that in following the track of Baron Cuvier, he has studied 

 with the greatest care that branch of knowledge which has been termed Zoog- 

 nosy. According to the form of the teeth he divides the genus Elephas into five 

 species : 



1st, Elephas mammonteus, whose remains have been found in a great number of 

 localities in Russia; among which he adds, to those which Pallas has recounted, 

 the sands which occupy the summit of the hills of Vorobieff near Moscow ; the 

 Rouza of the Moscowa, the mouth of the Lopasnia, in the Oca ; and, generally 

 speaking, the alluvium of all the rivers in the government of Moscow ; in that of 

 Vladimir, the environs of Lake Pereslavl, and the shores of the Oca, near Mou- 

 rom ; in that of Kalouga, the banks of the Ister, where a tusk of this animal has 

 beenibund among others ; in that of Toula, a great number of localities, such as 

 the banks of the Ocetr and of the Oca, the environs of Verew and Kachira ; in 

 that of Riazan, the district of Zaraisk, and the banks of the Pronia ; in that of 

 Orloff, the sandy banks of the Nougr; in that of Pollava, the banks of the Ou- 

 dal ; lastly, in that of Orel, the district of Briansk. 



2d, Elephas panicus, so called because the lateral furrows of the molars re» 

 mind one of the flute of Pan. This precious relic, figured in the Memoirs of the 

 Academy of St, Petersburg, was found in the government of Moscow ; but was 

 destroyed at the burning of that city. 



3d, Elephas periboletes, of which a tooth has been discovered on the banks of 

 the little river of Vekcha, district of Yourief, government of Vladimir. 



4th, Elephas catnpylotes, an extremely rare species, of which the University 

 of Moscow possesses a tooth ; but of which the precise locality is pot known. 



