284 Scientific Geology. 



tus traversing quartz, which, by the coloring matter of the asbestus, 

 was converted into prase. (No. 391.) 



Organic Remains. 



Having been disappointed in several efforts to obtain organic relics 

 in the graywacke formation, where I knew them to exist, I am pre- 

 pared to give only a meagre account of them in this place. 



All those which I have met with, were probably of vegetable 

 origin. 



In Taunton I was shown several imperfect specimens obtained 

 near the village, which evidently belong to some of the gigantic races 

 of plants now extinct, which flourished in the earlier periods of the 

 world. I recognized them as bearing a strong resemblance to some 

 of the larger species occurring in the coal mines in the valley of 

 Wyoming in Pennsylvania : but having had no opportunity to com- 

 pare these specimens with drawings, or descriptions, I can describe 

 them only in general terms. 



In Attleborough, east parish, a mile south of the meeting house, I 

 found an organic relic in a dark hard slate, which so much resembles 

 the Fucoides found in the new red sandstone of the Connecticut val- 

 ley, that I cannot but refer it to that genus ; not, how r ever, without 

 doubts as to its nature. (No. 400.) 



According to Dr. Webb,* vegetable impressions are found on slate 

 in Pawtuxet, which lies on the west shore of Narraganset Bay, 

 south of Providence. They seem to belong chiefly to the fern tribes. 



The same is true, I believe, of those found at the coal mines in 

 Portsmouth. It .was probably from this locality that the two speci- 

 mens mentioned in De la Beche's Manualf were obtained. One is 

 the fern Pecopteris arguta ; and the other, the anomalous plant, As- 

 ter ophyllites equisetiformis ; which as yet has been referred to no es- 

 tablished class. 



In the southeast part of Newport, where occur some narrow beds 

 of anthracite, vegetable remains are common. Of two of these I have 

 given a sketch. Plate XL fig. 10, bears considerable resemblance to 

 an Equisetum, as figured by Adolphe Brongniart on plate 12, fig. 

 13, of his Vegetaux Fossiles. Plate XIII. fig. 43 maybe a delicate 

 species of Nevropteris of the same author. I noticed there some 

 other species of the same genus. 



* Am. Journal Science, vol. 8. p. 225. 

 t P. 416 and 419, second edition. 



