FAUNAS OF SOUTHEASTERN ALASKA 325 
a bedded igneous rock, with which the limestones appear to be con- 
formable. Both series are shown in Fig. 3. An estimate of the 
thickness of the beds along the south shore of the island gives the 
following section exposed between the east end of the island and 
the inlet to the Salt Pond: 
Feet 
c. Hard, dark-gray limestone, slightly darker thanb . . . . - 270 
b. Hard, blue, fine-grained limestone, fracturing easily in any mecton . 200 
a. Stratified buff or cream-colored siliceous beds of igneous origin . . . go 
560 
Fic. 4.—Middle Devonian limestone, Long Island. 
The two divisions of the limestone series are conformable with 
each other, and the upper and lower portions are very similar in 
lithologic characters. Fig. 4 shows the lower beds of division c. 
The faunas of the two divisions of the limestone, however, show 
marked differences. The fauna of the upper portion of the lime- 
stone series was first discovered by Brooks, who collected some 
fossils from it which Schuchert determined as Middle ‘Devonian.' 
The lower fauna appears not to have been represented in the collec- 
tion studied by Schuchert. The character of the fauna in the lower 
portion of the limestone series is indicated by the following list: 
t Professional Paper No. 1, U. S. Geological Survey, p. 43. 
