

CONCLUSIONS. 95 



nessee, and Cumberland, and Alburnops microstomus in the James, Roa- 

 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. 



Eucalia inconstans occurs from Western New York to Kansas and 

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

 miles souih of Lake Erie. Percopsis guttatus has a like range, but its 

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

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

 of Ly thrums have each a belt of latitude : L. cyanocephalus belonging 

 to the Great Lakes and Upper Mississippi; L. diplccmim to the Ohio 

 and the Potomac; L. ardens to the Eoanoke, James, and Cumberland. 

 The iluee species of Hyodon are similarly arranged. 



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

 occuniug in the waters of the Upper Mississippi, in the headwaters of 

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

 New En-laud, thence to South Carolina on the eastern slope of the 

 Alh'>h<mie8. Such species are Eupomotis aureus, Perca amcricana, and 

 Am in r it a callts. 



XXVI. Certain species have a peculiar northern and western range, 

 oecimiii"- in the Middle States and in the Great Lakes, and usually 

 soutlt id in the east to some point in Virginia or North Carolina, 

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

 tern! i - south westward through the Mississippi Valley to the Gulf of 

 Mi xi o. Among these may be mentioned Luxilus cornutus, Notemiyonus 



<L;MV, Ambloplites rupestris, Apomotis cyanellus. The last-named 

 spec. !io\vi>ver, scarcely ranges east of the Alleghauies. 



XX VII. Certain species have a wide range north and south, either 

 ea:st < . est of the Alleghauies, but do not cross that chain. Of these 

 may h eutioned Lepiopomus auritus, Enneacantlius obesus, Esox reticu- 

 latnx. -.. on the east, and Haploitionotus grunniens, Hyodon tergisus, 

 Not a. , ,;. turns, Noturus sialis, etc., on the west. 



XX 'I. The distribution of fresh-water fishes is dependent (a) on 

 Ires;. el- communication ; (b] on character of stream, i. e., of water as 

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

 tin- i .i-d ; (d) on climate, as determined by latitude and by elevation 

 abo\, sva; and (e) finally on various unknown factors arising from 

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

 logic, i -toiy of the rivers. 



