CONCLUSIONS. 95 



nessee, and Camberlaud, and Albiirnops mierostomus in tbe James, Eoa- 

 noke, Kentucky, Cumberland, and Clinch. 



XXIV. Certain species have a wide east and west range, without 

 apparent regard to the courses of the rivers, but are bounded on either 

 the north or the south by parallels of latitude. 



EucaUa inconstans occurs from Western New York to Kansas and 

 northward, but it is never found southward of a line passing about fifty 

 miles south of Lake Erie. Percopsis guttatua has a like range, but its 

 southern boundary is in the Potomac and Ohio. Lota lacustris is simi- 

 larly circumscribed, but ranges farther to the east. The three species 

 of Lythrurus have each a belt of latitude : L. cyanocephahts belonging 

 to the Great Lakes and Upper Missihsippi ; L. diplccmius to the Ohio 

 and the Potomac ; L. ardciis to the Eoauoke, James, and Cumberland. 

 The three species of Hyodon are similarly arranged. 



XXV. Certain species have a peculiar northern and eastern range, 

 occuning iu the waters of the Upper Mississippi, in the headwaters of 

 the Illinois, Wabash, and Scioto, thence through the Great Lakes to 

 New England, thence to South Carolina on the eastern slope of the 

 Alleghauies. Such species are Eupomotis aureus, Perca americana, and 

 Ainiurus cat u ft. 



XX VL Certain species have a peculiar northern and western range, 

 occurring in the Middle States and in the Great Lakes, and usually 

 southward in the east to some point in Virginia or Xorth Carolina, 

 ceasing iu the same latitude on both sides of the Alleghanies, but ex- 

 tending southwestward through the Mississii)pi Valley to tlie Gulf of 

 Mexico. Among these may be mentioned Luxilus coniuitis, XotemigonuH 

 chrynoleucus, Amhloplites nqjetitris, Apomotis cyanellus. The last-named 

 species, however, scarcely ranges east of the Alleghauies. 



XXVI 1. Certain species have a wide range north and south, either 

 east or west of the Alleghanies, but do not cross that chain. Of these 

 raaj' be mentioned Lepioponnis aiiritus, Enneacantlius ohesns, Esox reticn- 

 latns^ etc., on the east, and HaploUlonotus grunniens, Hyodon tergisus, 

 Notiirus miiinis, Hfoturna skills, etc., on the west. 



XXVllL The distribution of fresh-water fishes is'"dependent {a) on 

 fresh-water communication ; {b) on character of stream, i. c, of water — as 

 to puiUy, depth, rapidity, vegetable growth, etc.; (c) on the character of 

 the river-bed ; {d) on climate, as determined by latitude and by elevation 

 above the sea; and (e) finally on various unknown factors arising from 

 the nature or past history of the species in question, and from the geo- 

 logical history of the rivers. 



