38o 



BULLETIN OF THE BUREAU OP FISHERIES. 



Where 8 rays are recorded the last is cleft to the base, the distinction in this case being somewhat 

 arbitrary. The scales in the lateral series number from 49 to 59, the most usual number being 50 to 56. 



In shape the scales are more or less quadrangular, although elongate and spatulate specimens often 

 occtir. The basolateral angles are strong and well marked. The apicolateral angles are usually weak. 

 Lateral radii are not common, and not over two have been observed on one side of a scale. The apical 

 radii number from ir to 25. 



This form differs from those of the Navarro and Gualala Rivers in being more slender in outline, 

 in having somewhat longer and more pointed fins, and a different number of fin rays, H. navarroensis 

 having generally 8 dorsal and 8 anal rays, and H. parvipinnis 8 dorsal and 7 anal rays. 



Minnows were seen in large numbers in the pools of Olima, Bear Valley, Papermill, and Walker 

 Creeks. They were especially abundant in Walker Creek, where they were considerably smaller than 

 those of Papermill Creek. In the latter stream specimens were collected October 21 which measured 

 130 millimeters, something more than 5 inches in length. An attempt was made to determine the age 

 of some of these from an examination of the scales, and it appeared that fishes measuring from 100 to 

 130 millimeters in length were in their third year; those measuring from 70 to no millimeters were in 

 their second year; individuals hatched in the previous spring were from 70 to no millimeters long. 

 None was seen which appeared to be older than the third year. 



Measurements of 10 specimens from Papermill Creek are here given. 



Measurements op Ten Specimens of Minnows, 'Papermill Creek. 



Length of body mm 



Length head 



Depth body 



Depth caudal peduncle 



Length snout 



Diameter eye 



Interorbital width 



Depth head 



Snout to occiput 



Snout to dorsal 



Snout to ventral 



Length base of dorsal 



Length base of anal 



Height dorsal 



Height anal 



Length pectoral 



Length ventral 



Length caudal 



Dorsal rays 



Anal rays 



Scales lateral line 



Scales above lateral line 



Scales below lateral line 



Scales before dorsal 



o- 34 



•35 



. II 



.08s 



• 06s 



• 09 



• 19 



• 22 



•57 

 •52 



■ 13 



. 10 

 . 20 



.18 



• 23 



• 17 



• 275 



9 

 S 

 52 

 13 

 8 

 33 



Salmo irideus Gibbons. Rainbow trout. 



Small trout were plentiful in Papermill and Olima Creeks. A few were seen in Walker Creek. 

 Large steeUieads c»me Ln from the bay immediately following the first heavy rains of winter. 



Gasterosteus cataphiactus (Pallas). Alaska stickleback. 



This species enters all the streams which flow into Tomales Bay. 



