174 E. Orton — Bituminous matter in Ohio Black Shales. 



I do not know, however, that spores have heretofore been 

 shown to supply bituminous matter in large amount to any 

 formation older than the Carboniferous. 



If the construction placed upon the facts recorded in this 

 ill be accepted, and vegetable spores shall be recog- 

 nized as a chief source of the bituminous matter of these black 

 shales, the perplexing question as to their origin will have 

 been carried one step further back. 



These black bands of the Huron shale lie geologically not 

 far below the Venango oil-sands of western Pennsylvania. 

 The resinous substances now described seem to offer .an ade- 

 quate and natural source of the petroleum and gas with which 

 these rocks are charged. Dr. Newberry has long insisted on 

 irtcy of these beds and of these only for this supply, 

 and he has sagaciously noted the fact that the carbonaceous 

 matter of these shales consists mainly of hydro-carbons. The 

 discovery of an ample supply of resinous spores within the 

 substance of the shales certainly strengthens the claim that has 

 been made for them as the main source of the valuable accu- 

 mulations of oil and gas of the sandstones and conglomerates 

 that overlie them. 



P. S. Since writing the above I have learned, through corre- 

 spondence with Principal J. \V. Dawson of Montreal, that he has 

 already recognized and described the most characteristic of the 

 forms above referred to under the name of S/,nr<ni</it< s ///'/•>>/'- 

 ensis. (See this Journal, April, 1871, page 2.1".) The specimens 

 on which his description was founded came from the bituminous 

 shale of Kettle Point, Lake Huron. A bed of brown shale, burn- 

 ing with much flame, of Upper Devonian age, from twelve to 

 fourteen feet in thickness, occurs here. The spore-cases are 

 described as flattened, disc like bodies, scarcely more than one- 

 hundredth of an inch in di.u externally, 

 with a point of attachment on one side and a slit more or less 

 elongated and gaping on the other. In sliced sections of the 

 rock, they appear yellow like amber and show little structure, 

 except that the walls can sometimes bo distinguished from the 



Dr. Dawson refers the spore-cases to Lycopodiaceous 

 m ,l suggests two species of Lepidodendron, the remain- i 

 ire found al the s:i„i. ;,m S h t l iera 



Fdtheimiamuo and L. Uu^umim. ' 



Columbus, Ohio, June 1, 1882. 



