02 SKETCH OF THE GEOLOGY OF CENTRAL INDIA. 



The other is of an emerald- green color, translucent or semi-trans- 

 parent. It occurs in grains or crystals of nearly a similar form to the 

 last, but these are frequently flattened. It also occurs in small irregular 

 grains which assume no distinct form. Like the first, it exhibits a very 

 fine fibrous structure. It has a shining vitreous aspect — it is soft, so as to 

 be scratched by the knife, but it is harder than the other ; it is exceeding- 

 ly brittle. Its fracture appears to be foliated, and its specific gravity 

 does not exceed that of the last. When exposed to the flame of the blow 

 pipe, it acquires a darker color, and becomes opaque and friable. 



The above minerals appear to be more allied to apatite, than to any 

 other substance with which I am acquainted. The friend to whom I am 

 indebted for my specimens informed me, that the rock in which these 

 are found occurs very abundantly on the route from Udayapur to Serot. 

 A specimen of this rock I have the pleasure to forward. 



I have only further to add, that I have found imbedded in JctinJcer, 

 in the valley of Udayapur, several varieties of primitive rocks, which I 

 have not yet been able to discover in situ. Of these I may mention one. 

 It has a waved appearance, is close grained, almost compact, and consists 

 of white quartz and a dark colored limestone, arranged in waved alternat- 

 ing layers. It eflervesces strongly with acids. A specimen of this rock 

 I have also the pleasure to forward. 



