456 PROCEEDINGS OF THE NEW YORK MEETING 



The shales which formed tlie transition to the Utioa must have heen very soft- 

 and therefore have ))een eroded away very readily, for nowI)ere have the transi, 

 tion heds between these two formations been found in position, wh(;reas in several 

 cases wiiere the succession of tlie series would lead us to expect to find them a 

 fiUed-in brook channel, beach, or fault will be found to intervene. 



The Utica slates have a thickness of several hundred feet throughout the valley, 

 and are quite uniformly of a rather soft friable character and the contained fauna 

 composed of small sized individuals. These rocks have suffered more from dynamic 

 metamorphism than those of the formations beneath. 



The early reports were inclined to consider the Hudson River group as being 

 largely I'epresented in the region. Most of the strata once referred to the group are 

 now known to be of Cambrian age. The islands in the lake referred to the Hudson 

 bj'^ the Vermont survey have in several cases proved to belong to the Calciferous. 

 We nowhere found fossils which might be considered typical of the Hudson, such 

 as JPterinea demissa (Conrad), Catazyga erratica Hall, Dalrnanella emacerata Hall, C'yrto- 

 lites ornatus Conrad, Modiolopsis curta Hall, nor any of the graptolites referred to 

 that group bj^ Lapworth,* while all the fossils found in the upper strata were of 

 well known Utica facies. Professors Brainerd and Seely, at Shoreham, and Mr 

 Walcott, at Highgate Springs, employed the term " Hudson" for the upper portion 

 of the slates, simply because the thickness represented seemed to be greater than 

 that usually assigned to the Utica alone, and no fossils were found by them. On 

 Cumberland head and Grand isle, however, we found a thickness of strata prob- 

 ably fully as great, which contained scattered Utica fossils throughout. Erosion 

 and glacial plowing has no doubt removed a great thickness of deposits, but even 

 the elevated "outliers" already referred to give no indication that strata superior 

 to the Utica were deposited in the district. 



At numerous localities the rock is under stress and conchoidall}^ fracturing chips 

 of tlie tougher limestone fly off under a comparatively light blow of the hammer. 



Summary of the Sections examined 



IN GENEBAL ' 



As already stated, the detailed faunal lists for each section will be published else- 

 wh"ere. It is therefore only necessary here to give an idea of the completeness of 

 the sections studied before summarizing the faunal lists. 



LABBABEE POINT 



The most southerly section is that at Larrabee point, Addison county, Vermont, 

 nearly opposite historic fort Ticonderoga. A nearly continuous section is here 

 presented in a small abandoned quarry and along the shore, with a general dip of 

 10 degrees north. Over 40 feet of Calciferous and Chazy limestones occur in pro.Y- 

 imity to the base of the section, but the transition beds to the base of the Black 

 River are not shown. The section begins with 12 feet of compact black limestone, 

 with shaly partings, the fossil contents of which indicate that it belongs to the 

 top of the Black River or the lower Ti'enton. 



The entire section is nearly 110 feet thick, and terminates in the Trenton, al- 



*C. Lapworth : Trans. Roy. Soe. Canada, vol. iv, sec. iv, 1887, pp. 167-184. 



