1897.] NATURAL SCIENCES OF PHILADELPHIA. 457 



same shells are encountered in other beds of limestones and marls, 

 but very badly preserved and in the form of interior casts. 



The lower horizons of the Permian deposits appear more dis- 

 tinctly above and below in the ravine. There is visible 30 or 40 

 meters below the place just described, between variously colored 

 marls, a bed of sandstone and conglomerate in which are encountered 

 the shells and other remains of ganoids, accompanied by casts of 

 conchifers. 



From the plateau the view extends far into the valleys of the 

 Volga and Oka and over the terraces of the left slope of the valley. 



From Nijni- Novgorod to Moscoiv. — The railway from Nijni- 

 Novgorod to Moscow, following up the valley of the Klinzma 

 crosses a band of Permian, and later a long and narrow belt of 

 middle Carbonic limestones, following which it again crosses a 

 narrow band of Permian before reaching the Jura-Cretaceous or 

 Volgian on which it continues all the way to the ancient capital. 



The Oural excursion was thus concluded after having passed 

 rapidly over 3,750 kilometers, (2,330 miles) of the most important 

 of the geological horizons in south and east European Russia, in- 

 cluding a long and typical part of the Volga, nearly a sixth of the 

 entire length of the Oural Mountains both in Siberia arid in Europe, 

 and more than half the length of the river Kama. 



The insight which this journey affords to the geological structure 

 of central European and Asiatic Russia could not have been 

 obtained in any other investigation of equal length and time, nor 

 in any other less well prepared, illustrated, and conducted. 11 



11 The sincere thanks of all students of geology are due to his Imperial 

 Majesty, the Tsar, for the boundless liberality he extended to the foreign 

 visitors ; to the Kussian geologists for the enormous and intelligently directed 

 labor they devoted to the preparation of the means for demonstrating their 

 vast and difficult problems to hundreds of strangers ignorant of their customs 

 and language ; to their energy and pluck in carrying out their programme 

 without a mishap ; and to the hospitality and kindness of all classes of their 

 countrymen, who made the long journey a continuous succession of pleasur- 

 able experiences. 



