250 
AUG. F. FOERSTE 
Clarkoceras holtedahli is closely related to the genotype Clarko- 
ceras newtonwinchelli (Clarke) from the Shakopee member of 
the Canadian in Minnesota. A third specimen, here figured but 
not described (Plate XXVII, figs. 4, A, B, C) , possibly may be an 
Endoceratitic shell with a large siphuncle in contact with the 
ventral wall of the conch, as in Cameroceras tenuiseptum (Hall), 
but, in the absence of any definite knowledge of the siphuncle 
in this Bache Peninsula specimen, its generic reference remains 
impossible. 
Dr. Holtedahl was inclined to regard the Orthoceras limestone 
specimens figured by him as Cambrian. There is a possibility 
of their being Ozarkian instead, lllaenurus convexus Whitfield 
occurs in the Mendota member of the Ozarkian in Wisconsin 
and several Ptychopariae occur in the Ozarkian of Point Levis, 
in Quebec, and in the Potsdam of New York and in the Kittatinny 
of New Jersey, of which the latter also are regarded as Ozarkian 
by Ulrich. Possibly both Ozarkian and Canadian horizons are 
represented in the Orthoceras limestone of Bache Peninsula, 
since the cephalopods here described have a distinctly Canadian 
appearance. 
Above the Orthoceras limestone on Victoria Head is first a 
series of sandstones alternating with limestones, and next a 
^^bed of close-grained brown limestone, about 100 feet thick, 
some of the layers of which are fossiliferous. ’’ From this brown 
limestone Dr. Holtedahl figures a Hormotoma, a Maclurea, and 
a Bathyuriscus. The genus Hormotoma is represented by num- 
erous species in the Canadian. Maclurea also is represented 
by a number of species in the Canadian of Newfoundland, 
Vermont, and New York. If the pygidium figured from the 
brown limestone could be referred to Bathyurus or Bathyurellus 
instead of Bathyuriscus then again it would find numerous rela- 
tives in the Canadian. It seems possible, therefore, to regard 
the brown limestone in the upper part of the Victoria Head 
section as of Canadian or even of post-Canadian age. 
From Victoria Head, in his work on ^^Palaeontology of the 
Coasts 'of the Arctic Lands’^ (Quarterly Journal of the Geol. Soc. 
of London, Vol. 34, 1878), Etheridge reports the discovery of 
Maclurea magna Leseur, a typical Chazyan fossil. 
