C'urreiif Action in the Ordot'ician. — Euedonaiin. 873 
posed surface is only small (53 gi-aptolites have been counted) 
it could not be ascertained whether this opposite flow of the 
water was of wide extent or only the result of a small local 
eddy. 
Farther down the creek, in the gorge below the High falls, 
some 80 feet of shale are exposed, only the lower part of 
which is accessible. This as well as the numerous other expos- 
ures of Utica shale along the creek, is instructive on ac- 
count of the regular alternation of shales and banks of 
limestone which it exhibits. The readings which could be 
obtained in these exposures from the graptolites, bryozoans 
and the mud flow structure, ranged between N. 60 degrees E. 
and N. 80 degrees E. and gave as an average the E. N. E. 
direction, the bi^arings towards N. 60 degrees E. being the 
more common. 
''Flat Fulls'''' of J^ast (Canada creek. 
Here the change of the Trenton limestone into the Utica shale is well 
exposed. The regular succession of limestone bands and shales becomes 
here still more apparent than above. The writer sees from his notes 
that he counted and measured, beginning from the typical Tren- 
ton limestone, 95 regular alternations. While, at the base of this series 
the intercalations of shale are still very thin (a few inches), they increase 
in thickness towards the top, while the bands of limestone decrease at 
the same time. Together with the gradual change of the rock, a change 
in the fossils takes i)lace. The Trenton limestone here is rich in very 
large, conical and branched specimens of MonticuUpora lycoperdoii, 
fragments of laotelus gigas and Caitjinene senaria as well as in the 
Trenton brachiopods, while some bands consist entirely of crinoid 
joints. Monticvlipora shows the first and most marked change, in be 
coming smaller before disappearing, while the trilobites and brachio- 
X)()dR disappear without apparent change. In the ninth intercalation of 
shale two sjjecimens of Diplograptiis pristis were found, while Caly- 
meiie, Ortliis teNtiidinaria and MonticuUpora still continue in the su- 
perjacent limestone. At the 17th intercalation, the last specimens 
of Moiitlculipora were noticed, and Cali/meiw alone continued further. 
The 51st intercalation of limestone consisted entirely of crinoid joints. 
The shales in all these alternations up to the 50th, are almost barren, 
only an occasional Diplograptus priatin being met with. Then, heads 
of Trinrthras becki appear and soon become common in the shale, while 
the limestone begins to contain the whole carapax of the same animal. 
The rhabdoRomes of Diplograptus pristis, though met with in the .58th 
and Glth stratum of shale (in the latter also some specimens of Eudoce- 
)-as profeiforme and Trochonenm were observed) do not become couunon 
until the G9th stratum of shnles, where they, however, show no di- 
rection. 
