THE PLIOCENE PERIOD 845 



inent, and in general the characteristic features were intermediate 

 between those of the lowest men and the highest apes, as shown in 

 Fig. 559. The size of the brain was about two-thirds that of an 

 average man. The interpretation of this find has elicited much 

 difference. of opinion. By some the bones are thought to be those 

 of an abnormal man; by others, those of an ancestral type between 

 man and his more remote ancestry. 



The marine life. The record of marine life on the Atlantic 

 coast of America is extremely meager. The few forms which have 

 been found in southern New England (Gay Head, Sankoty Head) 

 show that species which then ranged from Bering Sea to the north 

 Atlantic, are now confined to temperate latitudes. 1 On the 

 coast of California the early Pliocene faunas indicate a temperature 

 lower than that of the Miocene, while the later Pliocene faunas 

 point to sub-boreal conditions. 2 On the other hand, Pliocene 

 fossils from Alaska (vicinity of Nome) indicate for this locality, 

 when the beds containing these fossils were deposited, a climate 

 similar to that of north Japan and the Aleutian Islands, where the 

 sea remains 'unfrozen, though Nome has now a sub- arctic climate. 

 Similarly Pliocene fossils from the northwest coast of Iceland 

 indicate a temperature no colder than 42 (mean) where conditions 

 are now arctic. 3 The apparent lack of harmony between the 

 phenomena of California and higher latitudes may perhaps be due 

 to the different horizons from which the fossils come. 



Certain fossils of Japan and California indicate intermigration, 

 or migration from a common center, sometime during the period. 



Map work. Many of the folios mentioned on pp. 726 and 771 afford good 

 sections of the Tertiary formations. In addition, the following folios may be 

 mentioned: Arizona, Bradshaw Mountain; Colorado, Ouray; Georgia, Rome; 

 Idaho, Boise, Silver City; Kentucky, Richmond; Maryland, Patuxent; Ne- 

 braska, Camp Clarke, Scott's Bluff; Washington, Tacoma, Ellensburg, Mt. 

 Stuart, Snoqualmie; West Virginia, Huntington. 



1 Dall, Jour. Geol., Vol. XVII. 



2 Arnold, Ralph, Jour. Geol., Vol. XVII. 



3 Dall, loc. cit. 



