OF WESTERN AND CENTRAL INDIA. 7 



conspicuous at the lower gateway leading to the fortress of Siugurh 

 near Poona.^ A little occurs in the Island of Bombay, and there is 

 a well marked bed on the Island of Slasette in which the Uuddhist 

 caves of Kanheri are cut. But the rock occurs almost everywhere, 

 and may be easily recognised by its irregular weathering, the sco- 

 riaceous blocks remaining in relief upon the surface precisely as in old 

 volcanic cones. Very frequently a thin bed of ash occurs between 

 different trap flowSj and this sometimes passes into the red clay or 

 bole so commonly interstratified with the traps, and which, also, 

 I am rather disposed to look upon as a form of volcanic ash. Mr. 

 Hislop considers this bole as sedimentary.f He may perhaps be right, 

 but I have never seen either pebbles or organic remains in it, and, as 

 before said, it is distinctly mixed at times with the scoriaceous breccia. 

 This does not, however, prove the bole not to have had a sedimen- 

 tary origin, as the volcanic scoriae might have been showered into 

 water as well as on land. 



5. Horizontaliiy of traps. Thiclmess of beds. — One of the most 

 remarkable characters of the traps is their surprising horizontality. 

 This is very conspicuous along the Syhadri range east of Bombay, 

 in the scarp south of Khandeish, throughout the vast tract of country 

 between Poona and Nagpoor, (about 400 miles,) and on the scarp of 

 the Malwa plateau, north of the Nerbudda. Where exceptions occur, 

 the dips are almost certainly due to subsequent disturbance, as along 

 the coast at Bombay and to the northward, in the Sathpoora and 

 Rajpipla hills, and on the lower Nerbudda. In most of these cases the 

 disturbance is proved to be of later date than that of the deposition of 

 the traps by its affecting contemporaneous or later beds of sedimentary 



* This was noticed by Malcolmson. 



t Quar. Jour., Geol. Soc, Vol, XI, p. 364 



( 143 ) 



