ZIGNO SIRENIA. KAUFMANN RIGI. 5 



senic, with innumerable small crystals of the red silver-ore, lie close 

 upon the bands of calc-spar, the quantity of silver contained in the 

 deposit being 5-59 per cent. The middle of the vein is occupied by 

 nickeliferous pyrites, associated with white sulphide of nickel, the 

 latter containing 3 per cent, of silver and 19 per cent, of nickel. 

 The finest crystals of the silver-ore occurred in druse -like cavities 

 between the white calc-spar and the arsenic. They varied in colour 

 from ruby-red to lead-grey. [Count M.] 



9. Remains of Sirenia found in Venetia. By Baron A. de Zigno. 



[Proc. Imp. Geol. Inst. Vienna, January 21, 1873.] 



In his ' Zoologia fossile,' published in 1827, Prof. Catullo gave a short 

 catalogue of the collection of the University of Padua, in which he 

 mentioned ribs of Manatus from Castel Gomberto. Tbe specimens re- 

 ferred to are two blocks of coarse limestone, containing 14 ribs, which 

 have all the characters of those of Halitherium. The author has found 

 fragments of similar ribs in the Miocene strata of Treviso. The most 

 important remains of these Sirenia have been found lately in the pro- 

 vinces of Verona and Belluno. The bones obtained on the Monte 

 Zuello, near Montecchio, in the Veronese, are the oldest, and were 

 imbedded, with fragments of the carapace of a turtle and teeth and 

 vertebrae of a crocodile, in a limestone which belongs to the lower 

 part of the zone of Serpula spirulcea. They consist of a skull, 

 wanting the lower jaw, 31 ribs, 27 vertebras, and several undeter- 

 minable fragments. 



The glauconitic limestone of the basin of Belluno, in which remains 

 of Halitherium are found, was formerly regarded as Eocene, from its 

 lying beneath the grey Miocene Molasse, and containing remains of 

 crocodiles and teeth of Oarcharodon, Pachyodon, and Rhinoceros ; but 

 the Miocene fossils found in it by M. Taramelli show that it forms 

 one whole with the Molasse which overlies it, and must also be re- 

 garded as Miocene. The bones found at Cavarzona, in this district, 

 include two fragments of lower jaws, an intermaxillary bone, frag- 

 ments of the zygomatic arch and of several ribs, and five vertebra?. 

 The species found in the two localities are distinct; that of Mon- 

 tecchio proves the existence of Halitherium in Eocene times. 



[Count M.] 



10. The Rigi and the Molasse-district of Central Switzerland. 

 By M. F. J. Kaufmann. 



[Proc. Imp. G-eol. Inst. Vienna, March 4, 1873.] 



M. Kaufhann's volume of the ( Beitriige zur geologischen Karte der 

 Schweiz ' relating to this district is to be regarded as a continuation 

 of his work upon the geology of Mont Pilate. 



In the district of the Rigi also the Caprotina-ftmestone proves to 

 be a facies of the upper part of the Lower Cretaceous formation, 



