Hunt.] 106 [June 2, 



period. The well smoothed pebbles are chiefly of quartzite and sili- 

 cious slates, including not a few which are marked with Scolithus. 

 In the Rappahannock valley, and between it and the Potomac, the 

 formation may be seen resting directly either on the massive second- 

 ary sandstone, or on the looser deposit situated next above, or on 

 the Eocene tertiary, which at some points occupies hollows in the 

 denuded surface of the sandstone. 



The President announced the gift of a large quartz crystal 

 from Japan, of the kind used in the formation of the well- 

 known Japanese crystal balls, from Capt. Rufus Crowell, 

 to whom the thanks of the Society were voted. 



June 2, 1875. 

 The President in chair. Twenty-five persons present. 



Dr. W. G. Farlow gave an interesting account, illustrated 

 by diagram and black-board sketches, of the most recent 

 investigations on the fertilization of Funsji. 



The following papers were then read: — 



The Decayed Gneiss of Hoosac Mountain. 

 By T. Sterry Hunt. 



In a communication to this Society, published in its Proceedings 

 for Oct. 15, 1873, I noticed the chemical decomposition and decay of 

 the feldspathic and hornblendic rocks of the great Atlantic belt. 

 This, in the Southern States, is seen to have penetrated to a depth 

 of one hundred feet or more, but as we proceed northward becomes 

 less and less evident; until in the hills of New England we find the 

 same rocks, hard, and with glaciated surfaces. It was argued that 

 this decay was a process which had been in operation from remote 

 antiquity, and that the products resulting from it had been the source 

 of the various argillaceous deposits from the earliest paleozoic to the 

 post-pliocene clays, since the removal and deposition of which latter, 

 the process of decay seems to have been insignificant in amount. 



