Geology and Mineralogy. 151 



specimen a portion was nearly 97 per cent carbonate of lime, 

 he organic tissues but 3-1 p. c. having disappeared; while in 

 her portion, less changed, only the interstices and cellules were 



carbonate of lime, as was 

 easily proved by an acid. 



6. Green Mountains. — On page 498 of the last volume of this 

 Journal (Supplementary December number), a note is inserted cor- 

 recting the blunders which have long circulated in Geographies, 

 Gazetteers, Encyclopedias, and New England Guide-books, as to 

 the Green and White Mountahis terminating in trap ridixes— 

 called West and East Kocks-in the vicinity of Xew Haven ; the 

 fact being that East Rock is but a short appendage (half a mile 

 long) to the system of trap dikes of the Connecticut valley, and 

 West Rock, a southern portion of the same system. Prof. O. P. 

 Hubbard has informed the writer that this extraordinary error in 

 New England Geography has the following forms in "The Im- 

 perial Gazetteer " published by Blackie & Son at Glasgow, Edin 

 burgh and London, in 1855. Under New Have?^, "Surrounded on 

 three sides by spurs of tbe Green Mountains." Under Greex 

 MouKTAixs, '' A mountain range commencing near New Haven, 

 Connecticut." Under Connecticut, " Some of its mountains, 

 particularly the Green Mountain range," etc. 



The Green Mountains consist of metamorphic rocks and are not 

 younger than Silurian. They have their greatest height in Ver- 

 mont, and there received the name. The mountain system extends 

 south through tnestern Massachusetts and western Connecticut, and 

 the whole is rightly called the Green Mountain chain. But the 

 trap ridges of the Connecticut valley, belong to the valley, and 



Quarternary, according to M. Garnier, include 

 ver jseocomian (Lower Cretaceous); Upper Lias (contain- 

 cuki ILimmeri) ; Lower Lias (containing Ostrea snblamel- 

 :c.); Upper Trias (containing ffalobia^ Lomelli) ; Lower 



.LViCiiin ti.U'innun<iian(i)\ upper 

 ; besides also crystallized rock>. 



of them auriferous, amijhibolite, 



coal is anthracitic, parti v gi 

 said to have been rendered 

 phyry. To the northwest 



. ine serpentine or magne^iaii rock- c^^wv a i.ir-*- pare o 

 island. The_ serpentine coutniiis In-.-ii/itr -r diali.iL'c <-hi 



'* veins" of chrysolite. It pa>>>i-> intu ubitr .ULfilhMHuus [j.rol 

 hydro-micaj schists, and these arc intim.itcly a^-<'ciateil wit 

 serpentinous schists'[facts which prove that'the serpentine i; 

 as Garnier states, igneous, but, like most serpentine rocks. 



