76 Geology^ ^c, of the Connecticut. 



lites. No. IJ. Gneiss like greyish while rock, consisting 

 of small rounded quartz pebbles, and sometimes of copper 

 and mica, cemenied by indurated clay. No. 12. Old 

 rtd sandstone, or t":e dead rock, being the fundamental 

 rock of these tioetz strata." (Kees Cyc. Art. Icthyolites.) 



Un''ler these circumstances I have thought it safe to de- 

 nominate the peculiar ro'ks under consideration along the 

 Connecticut, the coal formation. A more complete set of 

 them has been forwarded to Mr. Brongniart, and we wait 

 anxiously for his fi;.al opinion. The suspicious circumstan- 

 ces attending them and the occurrence of the coal hitherto 

 discovered in thin beds and veinsonly,renderitvery doubtful 

 whether extensive beds of this valuable mineral will ever be 

 found in them. They have been unsuccessfully explored 

 at South-Hadley, Soulhington and Westfield, Ct. But [ 

 would not wish to discourage further search. The decision 

 of the question above discussed, concerning the precise 

 rank they ought to hold in the rock formations of the globe, 

 is one of considerable importance, since it will depend on 

 that decision whether coal or copper or gypsum may be 

 sought after with the greatest prospect of success. They 

 have long been to me a fruitful source of perplexity, and 

 again and again have I returned from traversing them in 

 titter despair of ever determining their real geological rela- 

 tions. To denominate them the coal formation relieves, 

 lor a time, most of these difficulties : but that name will 

 (^heerfully be resigned whenever a more correct one shall 

 be proposed. 



Organic Remains in the Coal Formation. 



1. Icthyolites. 



These occur at "Westfield, Ct. and at Sunderland, Mass. ; 

 and it is said also at some other places, as at West-Spring- 

 field ; but I have never seen any, except from these two 

 localities. At Westfield they were found in exploring for 

 coal, lying upon bituminous shale. Two species at least 

 were recognized, one of which Mr. Brongniart calls the Pa- 

 Icethrissum freislebenense of Blainville. These impressions 

 have been so repeatedly and accurately described by Prof. 

 Silliman in Cleaveland's Mineralogy and the American 

 J our. of Science, that it is unnecessary to be more particular. 



