Records of the Geological Snrneg of India. 
[voL. XII. 
attempted. I'his easy solution of the difficulty might he adopted, were it not 
that other oh.scrvations independently require such original conditions as are 
implied hy oycrla]): in the little hills south of the railway between the Basi and 
Jatwara stations, 20 miles east of Jeypoi’e, a coarse conglomerate occurs at the 
junction of the Alwar and liaialo groups, containing lai-ge boulders of gneiss, 
quartzite, limestone, and of a banded jasjjideons rock, in a .schistose matrix. Now, 
it seems impossible, under any recognized doctrines of rock-foinnation, to consider 
such debris as this to be derived from the series in which it occure; and the 
gneiss bonldei’s especially require the supposition of a metamorphic series older 
than that of the Aiwalis themselves, and upon which an overlap of the Alwar 
quartzites might naturally occur. But no such rocks have been discriminated 
within the very large area of these formations explored. Should this strati- 
graplucal evitlence fail, it may be permissible to sugge.st some primitive conditions 
of rock-formation, involving some very rapid process of induration of deposits, or 
even their crystallization, to take the place of what is commonly implied by 
metamoiqihism; and also involving much greater facilities of very local distui-bance, 
whereby the same dejmsits may be strongly unconformable and in unbroken 
sequence, within close proximity. The proved extreme antiquity of the transi¬ 
tion rocks of the Indian Peninsula admits, perhaps, of some appeal to conditions 
differing widely from any standard of processes now in operation. These rocks 
may, indeed, be azoic in the original acceptation of the term—anterior to the 
appearance of life in this 2 )ortion of the earth’s surface. 
The foregoing remarks refer only' to the Arvali rocks, as hitherto described; 
but Mr. Hacket’s observations of last season lead him to extend these views to 
some rocks of the adjoining region to the east, although without a re-examination 
of these sections. The change offers an immediate relief from the difficulties 
stated on pages 51 and 52 of the IMauual. At the eastern edge of the Aiwali 
region, close along the scarp of the Vindhy'an scries, there appear in the Hindaun 
ridge some tyqpical representatives of the Gwalior series. In their standard area, 
to the east of the Vindhy^an basin, these rocks rest, undisturbed and completely 
unconformable, upon the gneiss of Bundelkhand; and the puzzle was to find a 
place for these Gwaliors of the Hindaun ridge, either between the Vindhyansand 
the Ai'vali scries, or between these and the Arvali gneiss; the former alternative 
being provisionally accepted as the least anomalous. It was thought that the 
peculiar composition of the Gwalior rocks and their local unconformity to the 
Arvali series forbade their being identified with this series. Now, however, 
Mr. Hacket considers that, as with the Mandan and Ajabgarh groups, so the 
Gwalior rocks must be brought within the horizon of the Raialo group, and for 
similar reasons. The most peculiar and prevailing character of the Gwalior 
series is the presence of jaspideous bands, generally of a bright red colour. The 
very special nature of this rock, however abundant locally, would be in itself an 
excuse for not insisting upon it as a character of wide extension. The objection 
is, moreover, modified by the occurrence of compact silicious bands in the Eaialo 
group, as in the hills near Sathana in Shaikhawati; near Chenpura, north-east 
of Basi railway station; and near Muhammad 2 mr, south of Kherli station. 
