NEOZOIC INVERTEBRATES 
IOI 
there is a considerable mass of coal-bearing strata belong¬ 
ing to the Kenai Series of Oligocene sediments, which 
logically should succeed the Eocene Stepovak Series 
of Chichagof Cove and vicinity, though their contact has 
not yet been observed. To the southward, on the north¬ 
ern end of Unga Island of the Shumagin group, these same 
Kenai beds are exposed and contain not only coal but an 
important series of leaf beds, from which their age has 
been determined. A tolerably full description of the 
stratigraphy of the Unga locality has been published by 
the writer 1 from observations made in 1865, 1872 and on 
various occasions since. A list of the plant remains, pre¬ 
pared by Dr. Knowlton, 2 has also been printed. 
Immediately above the beds of the Kenai Series in the 
Unga section appear, as the product of apparently con¬ 
tinuous sedimentation, a thinner series of beds of Miocene 
age containing marine invertebrate fossils. This Miocene 
deposit, much broken up by volcanic dikes and intrusions 
of lava, extends to the eastward, being found in various 
localities along the north shore of Popof Island immediately 
eastward of Unga, where the writer obtained fossils in 1874, 
and where Mr. Kincaid of the Harriman party also col¬ 
lected a number of specimens, to be discussed later. 
The only representative of the Eocene epoch known 
in Alaska previous to the date of the Harriman Ex¬ 
pedition was the Kenai Series, which had been referred 
by Heer to the Miocene and by others to the Eocene, but 
which has of recent years been recognized as Oligocene 
by the present writer and others. 3 
The discovery of unmistakable typical Eocene strata 
in Alaska, therefore, is of prime importance, as filling a 
1 Correlation Papers. Neocene. Bull. U. S. Geol. Survey, no. 84, 1892; pp. 
240-242. See also : Report on Coal and Lignite of Alaska by William Healey 
Dali, 17th Ann. Rep. U. S. Geol Survey, 1895-6, part 1, 1896, pp. 807-811. 
2 Report on Coal and Lignite of Alaska (supra), Appendix 1, pp. 876-897. 
3 Report on Coal and Lignite of Alaska (supra), pp. 838-9. 
