450 THE AZOIC SYSTEM AND ITS SUBDIVISIONS. 



(Mr. Hunt) to propose for it [the year before] the name of the Terranovan 

 System. At this point in the Address there is a reference to this Journal of 

 the preceding year, Vol. L, p. 87, 1870 ; and consequently by referring back 

 to this article by Mr. Hunt, I found this Terranovan detined, Mr. Hunt saying 

 that, according to Mr. Murray, the series Comprises 'several thousand feet of 

 strata, including soft bluish gray mica slates and micaceous limestones belong- 

 ing to the Potsdam group, besides a great mass of whitish granitoid mica slates 

 whose relation to the Potsdam is still uncertain.' As the Huronian is older 

 than the Potsdam, and this equivalency of the Terranovan is not corrected in 

 the Address, I thought I had reason for supposing that Mr. Hunt made the 

 White Moimtain series the newer. I acknowledge I prefer the view he now 

 presents, since the less definite the statement the better as long as we have no 

 sufficient facts for a conclusion." (Am. Jour. Sci., 1872, (3) IV., p. 105.) 



Our extracts taken from Dr. Hunt's Address * show, however, that 

 he did make the White Mountain series younger than the Green Moun- 

 tain series, and that Professor Dana was correct. Furthermore, it will 

 be shown that Dr. Hunt had advocated this view some time previous to 

 his delivery of the Address ; and that later he claimed to have advo- 

 cated this order of age at the time of the Address and previously. The 

 reader's attention is also called to the fact that in Dr. Hunt's Chemical 

 and Geological Essays (p. 326) the sentence, " A careful perusal of my 

 address will show that I nowhere assert that the rocks of the third 

 series (Montalban), on my line of section, are younger than the second" 

 series " (Huronian), is expunged, although tlie paper purports to be a 

 reprint of his reply to Professor Dana. 



It is possible that the reader will find the reason for this expurgation 

 in what follows. On May 1, 1871, some three and a half mouths be- 

 fore the Address was given, Dr. Hunt said : — 



" In a communication to the Boston Natural History Society on the 19th of 

 October last, and subsequently in the American Journal of Science for February 

 and March, 1871 (pages 84 and 182), I have expressed the opinion that tlie 

 porphyries .... are stratified rocks, belonging .... to the Huronian sys- 

 tem, or Green Mountain system I have in that same journal for July, 



1870, pointed out the fact that the Eozoon of Hastings county, Ontario, occurs 

 in a series of crystalline schists which I consider newer than the Huronian, 

 and the equivalent of the White Mountain gneisses and mica schists." (Bull. 

 Essex Institute, 1871, III., pp. 53, 54.) 



Dr. Hunt's remarks, published in the Proceedings of the Boston 

 Society of Natural History to which he above refers, are as follows : — 

 " I regard these two types of rocks (quartzo-feldspathic rocks and dioritic 

 * See ajite, p. 447. 



