170 Association of American Geologists and Naiuralists. 



Prof. Hitchcock read a paper " on a new species of Ornithieh- 

 nite from the valley of the Connecticut river, and on the rain- 

 drop impressions from the same locality." 



After Prof. Hitchcock^s observations respecting the bird tracks 

 of the Connecticut valley, Mr. hyell alluded to the subject of 

 the cause of the present dip of the formation, expressing the 

 opinion that it is due, in part at least, to an uplifting of the strata. 

 Prof H. D. Rogers mentioned the reasons which had induced 

 him to attribute the dip of the beds in the other great tract of this 

 new red sandstone, or that which ranges southvvestward from the 

 Hudson, to oblique deposition. A uniform northerly dip of about 

 fifteen degrees prevails entirely across the basin, even where it is 

 twelve or twenty miles in breadth, and coexists with a manifest 

 shallowness of the deposit. This want of vertical depth is seen 

 in several places in Pennsylvania, where denudation has exposed, 

 in the interior of the tract, large patches of the older Appalachian 

 strata, upon which this new red formation rests unconformably. 

 No traces of dislocation occur to lead to the inference that the 

 shallowness of the basin is deceptive, and that the present want 

 of depth in the deposit has been caused by a succession of up- 

 throws with denudation. The steady northerly dip is very rarely 

 influenced, either in amount or in direction, by any of the numer- 

 ous dykes of trap which penetrate the formation. 



Prof. Rogers next mentioned facts which go to shew that 

 the formation of the Connecticut valley and the equivalent one 

 of the Middle States, are in all probability, accumulations in two 

 originally distinct estuaries. He mentioned as one evidence, the 

 independent direction of the dip in the two basins, and stated that 

 the absence of a parallel order of succession in the members of 

 the two formations, tends likewise to strengthen this opinion. 



Mr. Lyell conceived the steepness of the dip, which sometimes 

 amounts to twenty degrees, but more especially its direction, — 

 transverse to the course of the ancient estuary, to present a diffi- 

 culty. Prof R. endeavored however to shew that the present 

 dip might have been the original one, by suggesting, first, that 

 there is evidence in the nature of the materials of the great 

 southern basin for believing that they entered the estuary late- 

 rally on the outcrop side, by streams flowing from a country of 

 decomposing, talcose, chloritic and hornblende rocks ; secondly, 

 that if the channel was near the same shore, the velocity of the 



