FAUNAS OF SOUTHEASTERN ALASKA 335 
There appears to be no yellow sandstone member in the Saginaw 
Bay section. ‘The remainder of the fossils reported by Schuchert are 
from a sandstone, ‘‘burnt-umber in color,” which probably repre- 
sents a portion of division a of the above section. The fossils reported 
by Schuchert from this “burnt umber” sandstone are: 
Productus sp. undt. A Spirifer duplicicostatus Phillips 
Productus sp. undt. B Spirifer pinguis Sowerby 
Orthothetes crenistria (Phillips) Spirifer condor d’Orbigny 
The Upper Carboniferous limestone is terminated above by a 
Mesozoic limestone which rests unconformably on it. It is sepa- 
rated from the Lower Carboniferous series of Freshwater Bay by a 
series of cherts, dark shales, and sandstones of undetermined thick- 
ness. This limestone has a wide distribution in Alaska. In south- 
eastern Alaska it is known on Admiralty, Kuiu, and Kupreanof 
islands. In the interior of Alaska the fauna of this limestone has 
been found in the Copper River basin by Mendenhall and Schrader, 
and in the White River basin by Brooks. The same fauna occurs 
on the Yukon, at the mouth of Nation River, nearly 700 miles north- 
west of the Kuiu Island and Pybus Bay localities. It has not been 
found, however, north of the Arctic circle. It is absent from the col- 
lections of both Collier? and Schrader*+ from northern Alaska. The 
writer found no trace of it in the Porcupine River section in north- 
eastern Alaska. 
In the United States the formation bearing the nearest resemblance 
faunally and stratigraphically to the Upper Carboniferous limestone 
of southeastern Alaska is the McCloud limestone of northern Cali- 
fornia. In a report on a collection of fossils from the McCloud 
limestone published by Mr. Diller attention is called to the similarity 
of the two faunas by Dr. Girty, who suggests that it is such ‘‘as to 
indicate the extension of this fauna and possibly of the earlier Car- 
boniferous faunas of the California province to this region.”5 The 
thickness of the McCloud limestone has been estimated at from 1,000° 
t Professional Paper No. 15, U. S. Geological Survey, 1903, p. 46. 
2 Twenty-first Annual Report, U. S..Geological Survey, Part 2, 1900, p. 359. 
3 Bulletin No. 278, U. S. Geological Survey, 1906, pp. 22-26. 
4 Projessional Paper No. 20, U. S. Geological Survey, 1904, pp. 70, 71. 
5 American Journal of Science, Fourth Series, Vol. XV (1903), p. 351. 
© Geology of California, Vol. I, p. 326. 
