1897.] NATURAL SCIENCES OF PHILADELPHIA. 451 



contains large deposits of copper minerals (principally cupriferous 

 sandstones) which have been exploited until very recently and the 

 ore smelted at the works of Motowilikha. The lower horizon P* of 

 lower Permian can be seen in the mountain named Tschourbina 

 which is on the right bank of the Kama opposite the mouth of the 

 Tschoussowaia. This horizon of gray calcareous slaty marls inter- 

 stratified with gypsum and reddish brown sandstones carries the 

 bed Pi composed of greenish gray sandstone, interstratified with 

 reddish brown clay. The right bank of the Kama opposite the 

 city of Perm is low and barren, and formed of post pliocene de- 

 posits such as gray and brownish gray argillaceous sands with beds 

 of pebbles and recent deposits. A short distance down the stream 

 from Perm these sands lie on the Permian bed ~P\ which contains 

 somewhat cupriferous sandstone. 



Throughout the entire distance from Perm to the confluence of 

 the Kama with the Volga, the banks of the former river exhibit 

 exclusively Permian measures. The overlying beds are con- 

 sidered by some of the Russian geologists to be lower Triassic, but 

 others think they are not sufficiently well known to be ascribed 

 either to the upper Permian or the lower Triassic, and designate 

 them Permo-Triassic or PT, and call them provisionally Tartarian. 



For two thirds of the distance from Perm to the Volga only the 

 lower Permian beds P*, and Quaternary are seen, unless the deposit 

 at Kerakoulino below Sarapoul be considered Tartarian in accord- 

 ance with the views of some members of the Russian Geological 

 Survey. M. Stuckenberg, who is the author of L. G., XI, which des- 

 cribes the geology from Perm to Nijni-Novgorod. and was also the 

 leader of this part of the excursion, holds this to be erroneous. Ac- 

 cording to him the middle Permian (P 2 ) commences to appear at 

 Tikhia-Gory, and continues to Sentiaki where the upper Permian (or 

 Tartarian) appears and lasts to and beyond Tschistopol. The 

 further localities on the river from here to Laichew are credited by 

 him only with the middle Permian P 2 . For the rest of the Kama's 

 course, these higher beds with Quaternary persist. He states that 

 in the Kama section the lower Permian is represented by but one 

 member, V\, which consists of gray or brownish gray sandstone, 

 interstratified with more or less nearly red or reddish brown clays, 

 often containing calcareous concretions. Very rarely are found 

 remains of conchifers accompanied more frequently by remains of 

 plants. This bed is 70 to 80 inches thick in the sections near Perm, 



