74 
HeconU of the Geological Survey of India. 
[voL. III. 
hydrochloric acid, it is left undissolved, together with gelatinous silica. The 
excess of oxygen, and the presence of water, show that the hraunite is not in a 
pure state, having probably undergone partial alteration. 
The ore contains 55'27 per cent, of manganese and 6'91 of iron. The main use 
of manganese ores, however, is as oxidizing agents, their value depending on the 
amount of available oxygen they contain. Pyrolusite, or peroxide of manganese, 
the richest in oxygen and most valuable ore, contains when pure 18'39 per cent.; 
and ores are generally valuated by the percentage of peroxide they contain, or 
more coireetly speaking, the percentage of peroxide, to which the oxides they 
contain are equivalent in available oxygen. The average run of ores met with in 
commerce contain 60 to 75 per cent, of peroxide = about 11 to 14 per cent, of 
available oxygen. The Nagpur braunite contains 9'71 of available oxygen = 52 80 
per cent, of peroxide. As an oxidizing agent, therefore, it cannot be classed as 
more than fairly good. 
A deposit of the same class of manganese ore was found by Mr. W. T. 
Blanford in 1872, at the village of Kodaigowhan (near Khappa), 20 miles due 
west of Munsur, Great Trigonometrical Survey. 
Pal^iontologicai, notes pkom the Satpura Coal-basin, ly Ottokar Feist- 
mantel, M.D., Palwontohyist, Geological Survey of India. 
In the beginning of last year (1878) I had an opportunity of ti-aversing 
from east to west a portion of the great Sdtpura coal-basin, with the special 
intention of collecting fossils at certain places. Taking as guide the last report 
Mohpani field ground' I started from the Gadarwara station. 
Great Indian Peninsula Railway, for the Mohpani coal¬ 
field, of which a brief description was published" in 1870. 
With assistance of the manager of the MohpSni coal mines, Mr. Maughan, 
I was enabled to collect what fossils were to be got, which to some extent per¬ 
mitted of a comparison of the Mohpani coal seams (in part at least) with some 
other known horizon of the Indian coal strata, as given in my recently published 
flora of the Talchir sub-division." I shall repeat only what is necessary for general 
understanding in the present paper. 
In the report referred to, the close relation of the Talchirs and the coal beds 
in the Mohpdni coal-field is pointed out; and this view seems to be supported by 
the fossils, which bring these coal seams on the hoidzon of the Kaiharbari coal 
beds, which latter were recently shown to belong to the Talchir division. 
The fossils which I collected were found in a band of shale in the uppermost 
of the Mohpani coal seams, which are outcropping in the 
Fossil plants. valley of the Sitariva river, on the right bank of which 
the only mines of importance at present are situated. 
' H. B. Medlicott: Mem. Geol. Surv. of Indin, Vol. X. 
" H. B. Medlicott: Bee. Geol. Surv. of India, Vol. III. 
’ Fal. Indies, Ser. XII, 1. 
