EDITORIAL INTRODUCTION. 
I, THE GEOGRAPHICAL AREAS. 
(A) GENERAL ASPECT OF AMERICAN FISH Fauna. 
if a “American Fishes ” have been considered by Dr. Goode in groups 
arranged nearly, but not quite, in systematic sequence, according to 
views still held by many. The region covered, however, is by no means a 
faunal unit, but embraces several distinct faunas. 
First, we should separate the fresh-water fishes: from the inhabitants of 
the salt water. There are, it is true, many families which include both 
fresh-water and salt-water forms, such as the Herring family, the Salmon 
family, the Killie-fishes or Cyprinodonts, and the true Bass group; there 
are also those which are anadromous, spending part of the year in the sea 
and ascending the rivers for spawning, such as the Salmons and Shads ; 
there is, furthermore, one fish—the Eel—that is catadromous, in part 
spending some time in the fresh water, but descending to the sea to pro- 
create. Nevertheless, most of the fresh-water fishes of America (unlike 
those of some other countries) are peculiar thereto, belonging to groups dif- 
fering much from salt-water types: such are the vast families of the Suckers 
or Catostomids, the Carp-like fishes or Cyprinids, and the Catfishes or Silu- 
rids; others are less unlike salt-water forms, but nevertheless represent 
peculiar families, as the Black Bass or Sunfish family (Centrarchids) and the 
Cichlids, so characteristic of the warmer sections of America. 
(B) FresH-WaTER FISHES. 
We soon find that the fresh-water fishes of the westernmost part of the 
continent are quite distinct, on the whole, from those of the middle and 
eastern ; that is, those of the streams emptying directly or indirectly into the 
Gulf of Mexico and the Atlantic Ocean. One noteworthy fact is that the 
middle west and the east, in spite of its immense rivers, have no Cyprinids 
as large as many of those characteristic of Europe; while in the smaller 
streams discharging into the Pacific, immediately or mediately, there are 
many. In the east the Suckers represent, to some extent, the Barbels, 
Carps, and other large Cyprinids of Europe. 
