NOTES ON FRESH WATER FISHES OF THE PACIFIC 

 SLOPE OF NORTH AMERICA.* 



BY CLOUDSLEY RUTTER. 



The present paper contains studies of fishes from cer- 

 tain regions of the Pacific Slope, and is based on material 

 in the museums of Leland Stanford Jr. University and the 

 California Academy of Sciences. In its preparation I 

 have been under many obligations to my teachers in ich- 

 thiology, Professor Charles H. Gilbert and President 

 David S. Jordan. The paper is divided into four parts, 

 each independent of the others. 



I. 



ON THE STICKLEBACKS OF CALIFORNIA, WITH SPECIAL 

 REFERENCE TO THEIR INDIVIDUAL VARIATIONS. 



The Sticklebacks of the Pacific Slope have been de- 

 scribed under ten specific names. Of these ten nominal 

 species, four — Gasterosteus obolarins Cuvier & Valen- 

 ciennes, Gasterostens insculptus Richardson, Gasterosteus 

 serratus Ayers, and Gasterosteus intermedins Girard — 

 have been shown by Jordan and Gilbert to be synonyms 

 of Gasterosteus cataphractus (Pallas). Three — Gasteros- 

 teus plebeius Girard, Gasterosteus inopinatus Girard, and 

 Gasterosteus pugetti Girard — are likewise known to be 

 synonyms of Gasterosteus microcephalics Girard. The 

 other species has been described under the one name 

 only — Gasterosteus zvilliamsoni Girard. 



The chief character used in distinguishing these three 

 recognized species is the completeness of the lateral 

 armor. This armature consists of a series of vertical 



Contributions to Biology from the Hopkins Seaside Laboratory. No. 6. 

 Peoc. Cal. Acad. Sci., 2d See., Vol. VI. ( 18 ) June 22, 1896. 



