PART 4.] Ifaagen: Geographical distrilutmi of fossil organisms in India. 387 
with clay ironstone beds aggregating about 1,500 feet in thickness, and which 
conclude the Damuda series. 
Higher up follow, unconformably, conglomerates and coarse sandstones, which 
were originally regarded as representatives of the Mahadeva group, and which 
should jDei’haps still be regarded as such, but this question is hard to decide in 
the total ab.sence of fossils. The thickness of this latter division ranges from 
1,500 to 2,000 feet. To the south-east of Talohir, however, unquestionable Raj- 
mahal beds appear in the Atgarh coal-field; in South Rewnrh, on the contrary, 
the deposits of the Jabalpur group rest directly on the beds of the Damuda 
formation, and are of groat extent and thickne.ss. 
Of all the provinces the Satpura basin shows the most perfect series of beds. 
MedlicotD distinguishes numerous group.s which constitute the following 
series. Hirst of all is the Talchir ‘ boulder bed,’ resting on the crystalline rocks, 
above it come greenish and reddish clayey sandstones and sandy clays, also be¬ 
longing to the same group. On these lie.s the Barakar group, consisting chiefly 
of sandstones with intercalated coal seams, and having a thickness of from 400 
to 500 feet. Higher up follows a system of shales with included sandstone.s, 
within w'hich Medlicott, distinguished three groups, Motur, Bijori, and Almod. 
In the second of those remains of an Arclierjosanvus were discovered. Their 
total thickness is from 3,000 to 4,000 feet. Those are succeeded upwards by the 
Mahadeva series, which also forms three groups : at the base, the Pachmari group, 
consisting almost entmely of sandstones, and ranging in thickness up to 8,000 
feet; in the middle comes the Denwa group, composed of clays and sandstones, 
with occasional thin limestone beds, in all 1,200 feet thick. At the top comes 
the Bagra group, gi-ey and red conglomerates, 800 feet in thickness. The series 
is capped by the Jabalpur group, consisting of soft sand.stones 500 to 600 feet 
thick. 
Of some parts of Blanford’s fourth province we have again very good descriji- 
tions, especially those of W. T. Blanford, of the neighbourhood of ISTagpur.® 
Here, again, as in Bengal, Orissa, and on the Herbudda, we have first the Talchir 
boulder bed resting on the gneiss, but there is little more to be seen of the beds 
of that group. Above follow chiefly hard yellow sandstone.s, sometimes available 
as millstones, wliich compose the Kamthi group. Of the age of this group, as 
compared with the horizons recognized and described in other basins, it is very 
difficult to say anything with certainty, but it might perhaps be not quite erro¬ 
neous to place the Kamthis on the border of the Damuda and Panchet forma- 
tions.3 Above them the fresh-water beds of the cretaceous series (the Lametas) 
are well dovelopied. 
* Aledlicott: Mem. Geol. Surv. of India, X. 
^ W. T. Blanford: Mem. Geol. Surv. of India, IX, p. 295. 
® Dr. Peistmantel, in an essay apparently jrablislied in Calcutta (without mention of tlie place 
of publication, of the printer, or of the date), desires to have the Mangli beds, with Brachiops 
laticeps, Owen, regarded as Panchet, while Blanford asserts very distinctly that those beds are 
not sep.arable from the reniuinder of the Kamthis which Feistmantel assumes to bo Damudas. 
