108 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Table giving size of young salmon taken in Pool A, Sacramento River near Sims, 
with a comparative record from Pool E. 
The main value of this table is in showing the size of the young salmon in 
different months. The average size in August ivas 3.91 inches; that of the August- 
marked specimens taken in September, 3.86 inches, a very slight decrease. It will 
be noted later that there was a scarcity of food in September, which would account for 
a slight migration. In October the average size of the marked specimens increased 
to 4.20 inches, but remained the same in November. In the one month, September 18 
to October 18, there was an increase of 0.34 inch, but 1 lie total increase for the three 
months, August 18 to November IS, was but 0.29 inch, or 0.10 inch per month. This 
small increase for the total period indicates either that the growth was very slow or 
that the migration during that time almost compensated for the growth. During 
September, probably owing to a scarcity of food, the migration was a little greater, 
and as a result the fishes were smaller September 18 than they were a month before. 
There was a. decrease of 0.6 inch in December, when nearly all had left the pool. 
From measurements made on specimens taken at Olema, we have the following- 
table for age and size of young salmon remaining in fresh water: 
Age. 
Size, inches. 
Increase 
per month, 
average. 
Smallest. 
Largest. 
Average. 
Three months . 
1.7 
2.6 
2 2 
0.4 
Five months 
2.8 
3.3 
:i. n 
A 
. 36 
Seventeen months. 
7.0 
.35 
The growth in fresh water is, therefore, very slow, and in artificial propagation 
every effort should be made to prevent their remaining in the river over summer. 
The growth in salt water is much more rapid. The salmon should reach the ocean 
