i8 
BUI.I.ETIN OE THE BUREAU OF FISHERIES 
slightly narrowed from the center outward to about the twelfth, the outer rings show- 
ing again a decided widening. The significance of this midsummer check in growth 
during the first year is unknown. It is frequently wholly absent, may be present as a 
bare trace, or may become so well marked as to simulate the nuclear area of an indi- 
vidual of other species which spent its first year in the stream. 
But little is known concerning the dog salmon in their second year. Fine-meshed 
purse seines in Puget Sound, which take so many 2-year-old coho and king salmon, are 
said now and again to capture dog salmon also, but none have been seen by us. A 
single mature male in its second year, 2 1 inches long, was secured at Bellingham August 
3, 1910. As the habit of the species is to mature about equally during the third and 
the fourth years, this young male is properly to be designated a “grilse,” precociously 
developed a year in advance. Plate xiii, figure 24, presents the scale of this specimen. 
The run of dog salmon has not been adequately obserA^ed, as it occurs late in the fall, 
when most investigators have left the field. Examination of a larger series may well 
show that precocious individuals (grilse) are as numerous in this species as in the others 
thus far considered. Whether females as well as males mature in the second year 
remains to be ascertained. 
The series examined by the writer, exclusive of the fingerling and the grilse given 
above, consists of 58 mature individuals obtained at Bellingham August 2 and 3, 1910, 
ranging in length from 23 to 35X inches. They are so distributed as completely to cover 
this range in size. From the following table it will appear that the spawning fish are 
almost equally in their third and in their fourth years; or if there be any preference it is in 
favor of the third year. The two years overlap from the 26th to the 30th inches, inclu- 
sive, a size which seems to include the greater number of males in their third year and 
of females in their fourth. But the limited number of examples investigated is inade- 
quate to decide this point. A single large male, 35 % inches long, the largest specimen 
secured, was in its fifth year. 
Distribution of Males and Females, by Age and Size, in a Number of Dog Salmon, Chosen 
AT Random. 
