1.— THE FISHES OF THE KLAMATH BASIN. 
By CHARLES H. GILBERT, Ph. D., 
Professor of Zoology, Leland Stanford funior University. 
The Klamath Eiver rises in the arid region east of the Cascade Mountains in south- 
central Oregon. After expanding to form the Klamath Lakes, it cuts its way through 
the mountainous region of northern California and enters the sea nearly midway 
between the mouths of the Columbia and Sacramento rivers. It occupies, therefore, 
an intermediate and closely contiguous position with respect to these two great river 
systems, being separated from them in many places by narrow watersheds only. It is 
the more remarkable that its fish-fauna should contain nothing in common with either 
of them, save such auadromous forms as the salmon, trout, sturgeon, and him prey, 
which enter all the rivers of the coast. Such characteristic genera as Mylocheilus, 
Acrocheilus , and Columbia , of the Columbia River, and Mylopliarodon , Poyonichthys, 
Orthodon, Lavinia, Archoplites, and Rysterooarpus , of the Sacramento, have no represen- 
tatives in the Klamath. Even the genus Ptyclioclieilus is unrepresented there, though 
present in both the Sacramento and the Columbia, where P. yrandis and P. oreyonensis 
are but slightly different and are among the most abundant and characteristic fishes of 
their respective basins. A similar case is that of Cottus asper of the Columbia and 
Cottus gulosus of the Sacramento, two species so extremely similar that it is difficult to 
distinguish them, yet without any close relative in the Klamath. 
The relations of the Klamath fishes become at once apparent, however, when we 
compare them with those of the Lahontan and Bonneville basins of Nevada and Utah.* 
In each of these three localities the same genera occur — among them Chasmistes, which 
is not found elsewhere — and in many cases their species are so close as to be undoubt- 
edly representative. That the three areas have at one time formed part of the same 
hydrographic basin can not be questioned. Nor can we doubt that they have been 
separated for a very long period — long enough to permit the comp'ete differentiation 
of every species within each of them — for no species is now known to be common to 
any two of them, if we exclude the whitefish aud perhaps the trout, two forms which 
seem to be superior to any discoverable law of distribution. 
The Lahontan Basin has been very imperfectly explored, but the facts now at hand 
do not warrant the assumption that it has maintained a connection witli the Klamath 
at any time since its final separation from the Bonneville. Future exploration may be 
expected to throw light on this question. Important, also, will be a thorough survey 
of the lakes of southeastern Oregon which lie between the Lahontan and Klamath 
basins. Cope’s investigation of these leaves much to be desired, aud no facts are as 
* See Cope, “ On the Fishes of the Recent and Pliocene Lakes of the western part of the Great 
Basin, and of the Idaho Pliocene Lake.” Proc. Acad. Nat. Sci. Phila. 1883, pp. 134-167. 
. 1 
]T. 0. B. 1897—1 
