82 ROYAL SOCIETY OF CANADA 



It would therefore appear that in our present somewhat imperfect 

 knowledge as to the exact range of fossil plants, the precise determina- 

 tion of horizons must still be regarded, to some extent at least, as un- 

 satisfactory. 



An interesting series of bituminous shales and sandstones, with 

 thin bands of dolomite, occurs in Albert county, where it is known 

 under the name " Albert shale." Fossils, mostly confined to remains 

 of small fishes, are occasionally found in widely separated strata, and 

 sometimes the remains of plants are obtained. The formation, as a 

 whole, cannot be regarded as richly fossiliferous, though the rocks them- 

 selves are highly bituminous throughout. This formation rests upon 

 the flank of the pre-Cambrian hills of Albert county. 



In the special examination of this formation in 1876, it was clearly 

 shown that, stratigraphically, these shales underlie unconformably, the 

 lowest knoT\Ti lower Carboniferous sediments, agreeing in this respect 

 closely with the Devonian sediments near St, John city. From the 

 study of the few fossils which were obtained many years ago, chiefly 

 fishes, it was decided by Sir William Dawson, that their horizon was 

 lower Carboniferous; and in the colouration of the map of the district 

 they were accordingly so indicated, despite the stratigraphical evidence 

 to the contrary. 



Subsequently the stratigraphical sequence of a series of similar 

 rocks, found along the Avon river in ISTova Scotia, where they were long 

 known as the " Horton series," was established by Mr. Fletcher. They 

 were also found, like the Albert shales, to underlie unconformably the 

 lower Carboniferous of that district. From the evidence now at hand, 

 therefore, it may be asserted that the Albert shales of New Brunswick 

 are a part of the Devonian series of formations. 



The name " Dark argillite " series, which has already been briefly 

 alluded to in the remarks on Charlotte county, was given to the belt of 

 slates and sandstone with occasional schists and quartzite, which traverse 

 that county from the Maine boundary eastward. Their removal from 

 the Cambro-Silurian, where they were provisionally placed in 1877-78, 

 to the Upper Silurian system, as the result of recent investigation, will 

 involve a further study of several large areas of practically similar sedi- 

 ments lying to the west of the St. John river between Fredericton and 

 Woodstock, as also of the somewhat kindred rocks to the north of the 

 St. John in the direction of the Miramichi. 



In support of this contemplated change, it may be said that several 

 years ago upper Silurian fossils were found in the supposed Cambro- 

 Silurian rocks by Mr. W. J. Wilson, at a point a few miles north of 

 Canterbury on the railway line, so that doubt has existed for some time 



