210 Barrande, Logan, and Hall on 
Art. XIX.— Correspondence of JOACHIM BARRANDE, SIR WIL- 
LiAM LoGAN and JAmEs HALL, on the Taconic System and the 
age of the Fossils found in the Rock of Northern New England, 
and the Quebec Group of Rocks. 
more salient points. 
ocks under discussion occupy a belt of country east and 
west from twenty to sixty miles wide,.stretching from the vicinity 
of the city of New York in a northerly direction to Lake Cham- 
plain and thence through Vermont and Lower Canada to Cape 
Gaspé at the mouth of the St. Lawrence. The strata consisting . 
of slates, limestones, sandstones and conglomerates are greatly 
disturbed, plicated and dislocated, and are often, copaniall ee 
resemble in lithological characters those of the Hudson River 
group and thus along the western side of the region, where the 
masses 
and where the best of observers may arrive at diametrically 
oppos fe opinions. 
r. smmons, one of the geologists of the New York Survey 
Nevacif geolog 
manner in another work entitled “ THe Tacontc SysTEM,’ pub- 
lished in 1844. In this latter work he figured several species of 
fossils which had been collected in different parts of the forma 
tion. T'wo of these were trilobites and were described under 
JRE STS eS aa ee 
