3. The fishes of the eastern shores southwards to the latitude of San Francisco—Californian district; this corresponds to the North American district of the Atlantic.
Too little is known of the shore fishes of the coasts between San Francisco and the tropic to enable us to treat of it as a separate division.
The Shore fishes of the North Pacific generally are composed of the following elements:—
a. Arctic forms which extend into the Arctic Ocean, and the majority of which are also found in the British district.
b. Peculiar forms limited to the North Pacific, like the Heterolepidina, Embiotocidæ, and certain Cottoid and Blennioid genera.
c. Forms identical with fishes of the Mediterranean.
d. Peculiar forms limited to the southern parts of Japan.
e. Tropical forms which have entered the North Pacific from the south.
1. The small list of fishes which we can assign to the Kamtschatkan district is due rather to the imperfect manner in which its fauna has been explored than to its actual poverty of fishes; thus, although we may be sure that sooner or later the small kinds of Dog-fishes of the British district will be found there also, at present we have positive knowledge of the occurrence of only two Chondropterygians, viz. Chimæra and Raja. The species of the latter genus seem to be much less numerous than in the Atlantic.