FISHES OF STKEAMS FLOWING raTO SAN FEANCISCO BAY. 331 

 CATALOGUE OF SPECIES. 



1. Entosph.enus tridentatus (Gairdner). 



Taken by Mr. A. C. Ilerre in Coyote Creek, Marcli, 1905. 



2. Catostomus occidentalis Ayres. 



San Franciaquito, Madera, San Antonio, Stevens, Camp'oell, Guadalupe, Coyote, 

 Alameda, Arroyo Honda, Smith, and Isabel creeks. 



The species disappears from INIadera Creek during periods of great drouth, 

 returning when conditions are favorable. 



3. Orthodon microlepidotus (Ayres). 

 Coyote Creek. 



4. Lavinia exilicauda Baird & Girard. 

 Coyote and Alameda creeks. 



5. Pogonichtiiys macrolepidotus (Ayres). 

 Coyote Creek. 



6. Ptychoclaeilus grandis Girard. 



This species differs from P. oregonensis, its representative in the Columbia basin, 

 in liaving fewer dorsal rays (8 in P. grandis, 9 in P. oregonensis) and larger scales 

 above the lateral line (13 to 17 rows compared with 17 to 21 in P. oregonensis); 

 also, there are fewer rows of scales passing over the back between occiput and dorsal 

 fin in P. grandis (37 to 41, against 40 to 53 in P. oregonensis). 



The number of rows of scales above the lateral line is usually 14 or 15. Frequently 

 but 13 are present, while rarely as many as 16 or even 17 have been observed. The 

 pharyngeal bones appear to show no characters distinctive of the species. 



San Francisquito, Coyote, and Alameda creeks. 



Measurements of 10 specimens of P. grandis from Alameda Creek, Sunol, Alameda 



County, Cal.o- 



Sex 



Len^h of body in millimetera 



LeRgth of head 



Depth body 



Snout to dorsal 



Snout to ventral 



Depth caitdal peduncle 



Length caudal peduncle 



Length snout 



Length maxillary 



Diameter eye .' 



Interorbitai width 



Depth liead 



Length base of dorsal 



Height dorsal 



Length base of anal 



Height anal 



Length pectoral 



Length ventral 



Length caudal 



Dorsal rays 



Anal rays 



Scales lateral line 



Scales above lateral line 



90 

 .29 

 .22 

 .58 

 .57 

 .09 

 .16 

 .10 

 .11 

 .05 

 .08 

 .16 

 .11 

 .20 

 .09 

 .18 

 .18 

 .15 

 .29 



a Expressed in hundredths of the length of the body measured from tip of snout to end of last 

 vertebra. 



