ANNUAL EEPORT FOR 1876. 81 



sils in particular, and by its position." Mr. Yanuxem traced it in 

 that early date to Fort Plain, Cherry Valley, Richford Springs, vari- 

 ous points in Oneida county, Onondaga Valley, Syracuse, Auburn 

 and Cayuga Bridge. It must not be forgotten, however, as Sir Wm. 

 E. Logan points out (Geology of Canada, p. 363), that Mr. Vanuxem 

 confounded this group, in part, with the upper portions of the under- 

 lying gypsiferous series, which it closely resembles in lithological 

 character. 



The Lower Helderberg formation extends over a wide region of 

 North America. Becrafts mountain and Mount Rob, near the city 

 of Hudson, are isolated monuments of this geological epoch. The 

 formation extends, in a broken way, through Connecticut, Massachu- 

 setts, New Hampshire, Maine, New Brunswick and Nova Scotia. 

 According to Sir Win. E. Logan, there are outliers of Lower Helder- 

 berg at Point Gaspe and near Montreal, at St. Helens Island, at Round 

 Island, at Isle Bizard, at cuttings for the Grand Trunk Railway, be- 

 tween Point Claire and St. Anne. The distinguished chief of the 

 Canadian survey justly remarks (Geology of Canada, p. 358): "From 

 these scattering outlying patches, it would appear that a considerable 

 area in the Champlain and St. Lawrence valleys was once continuously 

 covered with rocks of the Lower Helderberg group; while from the 

 unconformable relation of these to the formations on which they 

 repose, it is evident that, prior to the Lower Helderberg period, the 

 older fossiliferous strata had suffered a great amount of denudation." 



This group extends along the Apalachian mountains southward, 

 through southeastern New York, New Jersey, Pennsylvania, Mary- 

 land and Virginia. The formation is thicker on the Potomac river 

 than on the Hudson. It thins out to the westward in the southern as 

 well as in the northern portion of the range. 



The Water-lime division of the Lower Helderberg enters Canada 

 opposite to Buffalo, and according to Sir Wm. E. Logan, " can be traced 

 pretty continuously, in a band varying from twenty to forty-five feet 

 in thickness." 



Although this language was used in the Canadian report of 1863, 

 yet strangely enough, Mr. Newberry, in the recent Ohio report, says 

 that the Water-lime group " had not been recognized beyond the limits 

 of New York previous to 1869." In that year Mr. Newberry dis- 

 covered the Water-lime subdivision of the Lower Helderberg on the 

 islands in the upper end of Lake Erie, and on the adjacent shore. 

 "Since our first identification of the Water-lime," he says (Geological 

 Survey of Ohio, p. 137), " we have traced it over a very large area 

 within this state, and have learned to recognize it almost at a glance 

 Wis. STIR. 6 



