170 OBITUARY, 



of the geological construction of Asia Minor, describes the Black Sea, of which it 

 has hitherto been supposed that, in consequence of some violent shock, its waters 

 opened a passage for themselves, and in so doing caused the deluge of Samothra- 

 cia ; but on examining the two sides of the Bosphorus, M. Tkxieb says they are 

 of such different strata that they never can have been united. The European 

 side is composed entirely of trachyte and analogous rocks, and the Asiatic of 

 transition limestone. The trachytes have a blue ground with white crystals, 

 and extend in a width of several leagues as far as Belgrade and Kila. If the 

 Bosphorus diminishes, as reported, it is probably owing to the effusion of the 

 trachytic rocks on the European side. 



Silex. — M. Turpin has submitted the silex sent from Berlin by M. Ehren- 

 berg, to microscopic observation. The magnifying power amounted to 260, and 

 this gentleman found, that the semi-opal of Berlin is a conglomerate of a number 

 of silicious particles and fragments of organic remains, the colour of which varies 

 from transparent white, and passes through yellow to the deepest and most 

 opaque brown. M. Turpin recognised four different bodies ; the first of which 

 he referred to the genus Gaillonella of M. Bory St. Vincent, or Conferva moni- 

 liformis ; the second he considered as a different species of the same genus ; the 

 third was a mixture of tubular filaments, divided into cells at rare intervals, and 

 remains of infusoria ; the fourth was not organic, but .served as a basis for 

 rendering the whole solid. The Silex pyromaque of Delitzsch is much richer in 

 organic productions, offering some very remarkable forms, probably belonging to 

 the eggs of Polypi. — Athenceum ; communicated by Charles Liverpool, M. D., 

 Plymouth May 9, 1837. 



OBITUARY. 



Professor Adam Azelius, the Nestor of scientific men in Sweden, died at 

 Upsal, Jan. 30, 1837, aged 86. He is the last pupil of Linnaeus, and celebrated 

 for his travels in Asia and Africa. His African Herbarium is now in the Bank- 

 sian collection in the British Museum. His younger brothers, John and Peter, 

 the former devoted to Chemistry, the latter to Medicine, are both distinguished 

 for their talents, and have, for nearly half a century, occupied chairs in the Uni- 

 versity, of Upsal. 



The learned botanist of the Cape of Good Hope, Mons. Persoon, is no more ; 

 he died at Paris, at a very advanced age, having lived there since he enjoyed a 

 pension from his government, which was granted to him on giving up his herba- 

 rium to the Museum at Leyden. His works on Cryptogamia are excellent ; and 

 his Enchiridion Bolanicum is one of the most useful works of the kind ever 

 published. 



