348 E. M. Kindle— Faunal Sxiccession in the 



species. It belongs to an undesoribed species and has been 

 referred to Megalodon sp. A Murehisonia of undetermined 

 species also identical with a species from Glacier Bay occurs 

 with the Megalodon. The presence of this large lamellibranch 

 here leaves no doubt of the equivalence of the limestone at 

 White Mountain to the limestone at Glacier Bay. 



On the north coast of the Seward Peninsula the writer has 

 found at Cape Deceit a fauna which appears to be the same as 

 the fauna at White Mountain. It is represented by a coral 

 which is probably a species of Amplexus and a lameilihranch 

 apparently identical with the Megalodon occurring at White 

 Mountain. The limestone at Cape Deceit has the highty mag- 

 nesian composition characterizing the limestone at White 

 Mountain. Since both the rocks containing this later fauna 

 and the fauna itself are here shown to be distinctly unlike » the 

 Port Clarence limestone of the type region and any of its 

 faunas, there remain no reasons for continuing to correlate the 

 two * as distinct formations. 



The correlation of two other small limestone areas which have 

 been referred to the Port Clarence, appear to require revision 

 in this connection. One of them is the limestone eminence 

 known as Black Mountain, located a few miles above White 

 Mountain on the Fish River. The other is Baldy Mountain 

 and the closely related Harris Creek locality near the center 

 of the Peninsula. Concerning the first Schuchert stated that 

 it "may also be Silurian. "f From the Harris Creek locality 

 Prof. Schuchert recorded three generically determined corals ^ 

 which he considered to indicate a middle Silurian age. An 

 important fact in this connection is that the collection compris- 

 ing the Harris Creek and Devil Mountain faunas does not show 

 a single species common to it and the large collection from the 

 typical region of the Port Clarence, Three fossils were cited 

 by Schuchert as evidence of the Silurian age of the fauna, 

 namely, Cladopora sp. resembles G. seriata Hall of the New 

 York Silurian ; Striatopora sp. ; Alveolites sp., a branching 

 form. 



The Cladopora of this list, which was compared with G. 

 seriata, a Silurian species, appears to the writer to resemble 

 G. Idbiosa, a Devonian species, rather more than G. seri- 

 ata. The additional evidence afforded by the writer's col- 

 lection is meager and, as in the case of the earlier collection, 

 rests on corals alone. It includes, however, a Favosites much 

 like F. radiciformis and a Diphyphyllum resembling D. archi- 

 acai. The latter appears to be identical with a Diphyphyl- 



* Bull. U. S. Geol. Survey No. 328, map, 1908. 

 f Bull. U. S. Geol. Survey No. 328, p. 77, 1908. 

 JOp. cit., p. 76. 



