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On August 29, 1897, I seined in the Sacramento near Sisson, and 

 found salmon ranging from 2.63 to 4.37 inches in length, with an average 

 length of 3.25 inches. On November 3, 1897, I seined again in the same 

 place, and found the salmon ranging from "3.25 to 4.50 inches, with an 

 average length of 3.92 inches. They had gained .67 of an inch in the 

 two months since the stream was seined before; or, for the eight months 

 which they had remained in the stream, an average gain of .32 of an 

 inch per month. In the two months their number had diminished about 

 one-half, which was the same falling off as found in Sulloway Creek. 



On November 6, 1897, I seined the upper Sacramento at Sims, and 

 found the average length of the salmon there to be 4 inches, although 

 they ran from 3.5 to 4.5 inches. 



On May 17th of the following year, a little over six months later, the 

 stream was again seined at the same place. The average length of the 

 young salmon at this time was 2.67 inches, although they ran from 1.52 

 to 3.76 inches. In this series the fry were hatched from eggs spawned 

 by two different runs, which accounts for the great difference between 

 the largest and the smallest of the series. Those in the upper end of 

 the series, and which average about 3.5 inches, had absorbed their yolk 

 sacs and begun to feed six months before, while the lower end of the 

 series represents those which had begun to feed only two months before. 

 If two hatches of salmon as young as these and with such a difference 

 between their ages had been found in a small tributary of the Sacra- 

 mento we could expect to easily separate the two sizes, but in the main 

 stream, as at Sims, where the young salmon are from several different 

 tributaries, a large variation in the size of the individuals occurs and it 

 is not strange that the two sizes cannot be readily distinguished. Out 

 of a very great number of small salmon caught here the largest was 

 scarcely larger than the smallest taken at the same place six months 

 before, which is the best evidence that none of those in the stream six 

 months before remained through the high waters of winter. If they 

 had remained until this time they would have been fifteen months old. 



In Hazel Creek, a tributary of the Sacramento near Sims, I found, 

 x>n November 6, 1897, two sizes of young salmon. The smaller size 

 varied from 2.65 to 2.95 inches, with an average length of 2.87 inches; 

 the larger size ran from 3.93 to 4.42 inches, with an average of 4.19 

 inches. The larger size greatly outnumbered those of the smaller size, 

 and agreed well with the size of the salmon in the Sacramento at Sisson 

 and at Sims. Of the smaller size only four were taken. Assuming 

 that they had grown at the same rate as the others, they must have 

 hatched from the egg early in August, and allowing three months for 

 hatching, they were spawned early in May. There is nothing remark- 

 able in the fact that salmon spawned here in few numbers at that time 

 of year. The first salmon of the spring run have been observed passing 



