VERMONT AND "WESTERN MASSACHUSETTS. 



447 



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tlitiir organic reiiiuins, tlie fossiliferous Tacoiiic rocks are shown to belong." 

 Q. c, pp. 22-24.) 



Dr. Hunt further remarked in his Presidential Address : 



" The crystalline infra -Silurian strata, to which the name of the Huronian 

 series has been given by the Geological Survey of Canada, have sometimes 

 been called Cambrian, from their resemblance to certain rocks in Anglesea, 



which have been looked upon as altered Cambrian The Anglesea rocks 



are a highly inclined and much contorted series of quartzose, micaceous, chlo- 

 ritic, and epidoLic schists, with diorites, and dark-colored chromiferous serpen- 

 tines, all of which, after a careful examination of them in the collections of tlie 

 Geological Survey of Great Britain, appear to me identical with the rocks of 



the Green Mountain, or Huronian series The gneissic series of the 



Green Mountains had, however, as we have seen, been, since 1841, regarded 

 by the brothers Rogers, Mather, Hall, Hitchcock, Adams, Logan, myself, and 

 others, as of Silurian age. Eaton and Emmons had alone claimed for it a pre- 

 Cambrian age, until, in 18G2, Macfarlane ventured to unite it with the Huro- 

 nian system, and to identify both with the crystalline schists of similar age in 

 Norway. Later observations in Michigan justify still farther this comparison. 

 . . . . This view [that the Wliite Mountain rocks were Upper Silurian and 

 Devonian] adopted and enforced by me, wvis farther supported by Lesley in 

 18G0, and has been generally accepted up to this time. Li 1870, however, I 

 ventured to question it, and in a published letter, addressed to Professor Dana, 

 concluded, from a great number of facts, that there exists a system of crystal- 

 line schists, distinct from^ and newer than, the Laurentian and Huronian, to 

 whicii I gave the provisional name of Terranovan, constituting the thirJ or 

 White Mountain series.'^ (Proc. Am. Assoc. Adv. Sci., 1871, XX., pp. 26- 

 28, 31, 33.) 



Wo invite the reader's attention to the use of the term Green Moun- 

 tain series as the equivalent of the Huronian, and to the statement that 

 the White Mountain series is newer than the Huronian, hoping that he 

 will remember it a short distance farther on. 



Prof.' J. D. Dana, in criticising Dr. Hunt's Address, remarked (Am. 

 Jour. Sci., 1872, (3) ill, pp. 92, 93) : — 



ii r 



That he has relied, for his chronological arrangement of the crystalline 

 rocks of New England and elsewhere, largely on lithological evidence, and 

 connnends this style of evidence ; — when such evidence means nothing until 

 tested by thorough stratigraphical investigation. This evi<lence means some- 

 thing, or probably so, with respect to Laurentian rocks ; but it did not until 

 the age of the rocks, in their rehitions to others, was first stratigraphically 

 ascertained. It may turn out to be worth something as regards later rocks 

 when the facts have been careful!}'" tested by stratigraphy. A fossil is proved, 

 by careful observation, to be restricted to the rocks of a certain period before it 



