A NORTH AMERICAN EPICONTINENTAL SEA OF 
JURASSIC. AGE 
I. Introduction. 
1. Statement of the lines of investigation. 
II. Nature and extent of the sea. 
1. Present known distrfbution of the deposits. 
a') South Central Wyoming area. 
6') Southeastern Idaho area. 
c') Northern Uinta area. 
d') Southern Uinta area. 
e') Southern Utah area. 
J’) Black Hills area. 
g') Montana area. 
A') Canadian area. 
z') Aleutian area. 
2. Conclusions. 
III. Relation of the interior fauna to the northern Eurasian fauna, 
IV. Connection of the sea with the ocean. 
V. Lack of communication between the Californian province and the interior, 
and the causes assigned. 
1. The climatic hypothesis. 
2. An alternative hypothesis. 
VI. General conclusions. 
INTRODUCTION 
The following line of investigation is the out-growth of the 
study of the faunal and stratigraphical conditions as they are 
expressed in the Jurassic formation of the Freeze-Out Hills in 
southern Wyoming.’ In making these investigations the writer 
has been led to test, in the light of new doctrines * and more 
recent observations, certain prevalent opinions bearing on Juras- 
sic faunal geography. In connection with these investigations 
there arose also questions concerning which no definite statement 
tLoGAN: Kansas Uni. Quart., April 1900. 
2See papers by Dr. T. C. CHAMBERLIN on: “A Source of Evolution of Provin- 
cial Faunas,” Jour. GEOL., Vol. VI, p. 598; “‘ The Ulterior Basis of Time Divisions,” 
2bid., p. 449. 
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