RICHMONDIAN SERIES 697 



Strophomena fluctuosa, Leptcena nitens or unicostata, Rhynchotrema 

 anticostiensis, and R. perlamellosa. On the east side of the axis in south- 

 western Ohio occur Streptelasma rusticum, Dalmanella meehi, Rhyncho- 

 trema perlamellosa, and Catazyga headi^ which is a local variation of C. 

 anticostiensis. 



On' the other hand, the strata of Division A continue without break 

 into those of Division B, where the Eichmondian fauna is in full develop- 

 ment, and it must therefore be concluded that the former division also 

 belongs to the Eichmondian epoch. The writers would, therefore, corre- 

 late the strata of Division A with the lowest two zones of the Ohio Eich- 

 mondian — that is, the Arnheim and lower Waynes ville. In the Arnheim 

 R. perlamellosa does not occur, but is present in the Waynesville — occur- 

 rences in harmony with the appearance of this shell on Anticosti. Of 

 course, it is possible that the Anticosti series may have begun somewhat 

 earlier than the appearance of this guide fossil in Ohio, and that there- 

 fore the basal zones of A are of highest Maysvillian time. As to this, 

 however, there is at present in the faunas no clear guidance. 



If the writers' correlations be correct that the black shale of Macastey 

 Bay is probably of Eichmondian time and not the equivalent of the Utica, 

 it follows that there is no time break between this black shale and the 

 limestones of Division A. 



Charleton formation {Richardson s Division B). — The strata of this 

 division are 730 feet thick and are seen from English" Bay east to Junc- 

 tion Cliff on the south side of the island, and on the north side as far east 

 as Table Mountain. Limestone conglomerate beds with small flat pebbles 

 occur throughout and intraformational conglomerates more rarely. The 

 zones of Eichardson are grouped as follows : 

 Rhynchotrema perlamellosa teds. ^^^^ 



Bj and Bj. Gray limestones directly above the "track bed" 55 



Bj, B^, and B5. Reddish gray limestones with few fossils 133 



On the north shore these zones appear to be at least twice as 

 thick, extending through fully 400 feet of strata above the 

 "track bed." 



Beatricea heds. 



B,. Reddish gray limestone with fossils more abundant 102 



Beatricea appear at the base of this zone, and on the south 



side of the island continue through 702 feet of the higher 



strata. 

 B^, Bg, and Bg. Gray limestones. Fossils are scarce, but the corals and 



Beatricea are here more common than below 179 



Bio. Gray limestones 165 



Bij. Concealed measures on south shore. On north shore the 70 feet 



of shale at the base of Point Joseph are thought to belong to 



this zone 96 



k 



