34 BULLETIN OF THE BUREAU OF FISHERIES. 



Table 31. — Data for 22 Fry from Butts Slough, May 8 and 9, 1911.0 



Tito 75 mm.. 

 66 to 70 mm., 

 61 to 6s mm.. 

 56 to 60 mm. , 

 51 to 55 mm.. 

 46 to 50 mm. . 



Av. 6j.9mm. 



Length- 



Number. 



a The specimens in this collection had all lost the scales as a restilt of poor preservation. 



Tablb 32. — Data for 20 Fry prom Pond nbar Elkhorn, Calif., June 3, igii. 



Length. 



Number. 



Scale record. 



Average 



number of 



rings. 



Average 

 length of 

 anterior 

 radius. 



8ito8snmi.. 

 76 to 80 mm. . 

 71 to 75 mm. . 

 66 to 70 mm . . 



10. o 



9.0 



8.5 



Av. 77.0 mm. 



35.4 



3S-3 

 34-8 

 27.6 



34-4 



This collection contained 11 males averaging 77.1 mm. in length and 9 females 

 averaging 76.9 mm. in length. 



The largest collection from the lower Sacramento River was made at Woods Break, 

 June 5 and 6, 191 1. (See Table 33.) There is a total of 147 specimens. One hundred 

 and fifteen of these were taken in a trap located at the point where the water was flowing 

 through the break from the main river, and 32 were seined from an overflow pond near 

 the break. The separate study of these two collections shows no essential difference, 

 and the data are, therefore, placed together in the following table (33). This collection, 

 undoubtedly, is a fair sample of the migrating fry in the Sacramento at this time of year. 

 The average length is 71.7 mm. The average number of rings on the scales is 8.2, and 

 the average length of the anterior radius is 30.5 on the arbitrary scale adopted. There 

 are j'j males in the collection averaging 72.2 mm. in length. The 70 females average 

 71.0 mm. 



Table :i,2i- — Data for 147 Fry from Woods Break, June 5 and 6, 191 1. 



Length. 



91 to 95 mm.. . . 

 86 to 90 mm — 



gi to 85 mm 



76 to 80 mm — 

 71 to 75 mm.. . . 

 66 to 70 mm... . 

 61 to 6s mm... . 

 56 to 60 mm. . . . 

 51 to 55 mm. . . . 

 46 to 50 mm .... 



Av. 71.7 mm. 



Scale record. 



Average 

 number of 



rings. 



II. 6 

 10. 1 

 9.0 



8-S 

 7.6 

 6.8 

 5-6 

 4.0 

 4.0 



Average 

 length of 

 anterior 

 radius. 



48-3 



43-0 

 37-3 

 33-4 

 31-4 

 37. 9 

 JS-8 

 23.0 

 30.7 

 20.7 



30.5 



