112 DEPOSITS OF PHOSPHATE OF LIME. [bull. 46. 
bed also crops out near Castellane and Nice. It is of very little com- 
mercial importance. 
The phosphate bed of Cote-d'Or consists of a bed of yellow sand of 
fine texture, mixed with shells, fossils, and phosphatic nodules, which 
often form a separate bed in the sand. The bed immediately underlies 
the gray and red clays of the Gault. 
PHOSPHATES OF RUSSIA. 
The principal phosphate deposits in Russia are found in the Creta- 
ceous formation, though deposits of very limited extent have also been 
found in the Tertiary, Jurassic, and Silurian. The Cretaceous phos- 
phates are developed here on a larger and more continuous scale than 
those of any other part of Europe or those of America. The main de- 
posit lies between the Volga and the Dnieper Rivers, and the area 
covered has been estimated by Yermoloff at 20,000,000 hectares (about 
50,000,000 acres). It begins in the government of Smolensk and ex- 
tends almost uninterruptedly in a southeasterly direction to beyond 
Woronesch. This area is about 370 miles long by 00 to 125 wide. South 
of this belt the phosphate bed is lost under the overlying beds, but it 
reappears again on the southern boundary of the Cretaceous basin. 
North of Woronesch the bed has been destroyed by erosion, but it is 
found again 125 miles northwest, in the neighborhood of the villages of 
Tambof and Spask and Simbirsk. Besides these principal localities, 
the phosphate bed is found in several other places between the Baltic, 
Caspian, and Black Seas. Mr. Yermoloff, [ in speaking of the great ex- 
tent of the Russian phosphates, says : 
Nous ne croyons pas exage"rer en affirmant que la Russie centrale repose sur du phos- 
phate de chaux, qu'elle pourrait en paver la moitie" de l'Europe, taut les couches 
qu'elle renferme sout ine'puisables de richesses. 
The Cretaceous series in central European Russia forms a basin, only 
the northern boundary of which has as yet been thoroughly explored. 
The phosphate beds are found at two different horizons in this formation. 
The first is at the base of the White Chalk or Craie Blanche, and cor- 
responds to the White Chalk bed of Ardennes and Meuse. The second 
is at the base of the Greensaud (Cenomauian, or Gres Verts) and is 
mixed with glauconite and sand. It corresponds to the beds of the same 
horizon in central and northern France. The deposit at the base of the 
Chalk is the most important, and the one most often seen. The phos- 
phatic material occurs in the form of shell-casts, nodules, and fossils, 
mixed together in a bed of gray or yellow sand, and is commonly known 
as "ssamorod" (native stone). The nodules are of a black-brown or 
gray color, and are often cemented together, forming a solid mass, which 
is used as a building and paving stone. The phosphate often occurs in 
several different beds, separated only by a thin layer of calcareous or 
•Alex. Yermoloff: Jour, agric. pratique, 1872, 
(586) 
