SALMON INVESTIGATIONS IN IDAHO IN 1895. 
197 
Total lengths in inches and comparative measurements of 45 young redjish taken in Alturas Lake 
September 9, 1895. 
Length. 
Head. 
Depth. 
Snout. 
Eye. 
Length. 
Head. 
Depth. 
Snout. 
Eye. 
n 
4? 
4i 
44 
3j 
24 
■14 
44 
J6 
34 
i 
ii 
4i 
4£ 
4 
3i 
44 
4} 
44 
3-1 
n 
ih 
44 
4i 
34 
34 
ih 
44 
5 
34 
4J 
44 
4 = 
34 
34 
4 
44 
44 
34 
3 
44 
44 
44 
3 
3 
« 
44 
5 
3 + 
3| 
44 
44 
4i 
34 
H 
44 
44 
5 
34 
3i 
4i 
45 
4j 
34 
H 
44 
44 
44 
34 
ii 
44 
54 
4 
34 
44 
44 
44 
34 
3| 
4J 
54 
4i 
34 
34 
44 
44 
44 
34 
3 
4 
44 
4 
34 
2| 
44 
44 
44 
3 
3i 
44 
5 
5 
34 
34 
4 
44 
44 
34 
3J 
41 
4J 
4i 
34 
3| 
44 
44 
44 
34 
3J 
4 
44 
44 
34 
34 
44 
44 
44 
34 
44 
44 
44 
34 
3-i 
44 
4:1 
4 + 
3-t- 
3i 
4i 
4| 
4i 
34 
3 
44 
5 
4 
34 
3 
4F 
4| 
5 
3 
3 
4-f- 
4j 
4 
34 
3i 
44 
44 
44 
34 
3 
4 
5 
44 
3 
3i- 
4 
44 
44 
34 
3| 
44 
44 
44 
34 
3 
4 
4§ 
44 
3 
3 
44 
5 
44 
3 
3(r 
44 
44 
4J 
34 
34 
44 
4,1 
44 
34 
3i 
44 
44 
44 
3i 
34 
44 
44 
4 
34 
3g- 
44 
44 
4 
34 
2f 
4 
4j 
44 
3 
2| 
4 
5 
44 
3 
‘ Deformed. 
On September 12 the seine was again hauled in the same place and 4 young redfish were caught. 
They measured 3,^y, 3^, 2|-, and 2-J inches, respectively. The difference in size between those taken 
July 20 and September 9 and 12 is very noticeable, and throws light upon their rate of growth. 
These young redfish at first sight might easily be mistaken for young front or young chinook 
salmon. They can best be distinguished from young trout by the larger number of anal rays (13 to 16 
in the redfish, 9 to 12 in the trout), the more slender Imdy, and the paler coloration. From young 
Chinook salmon they may be kjiowii by the more slender body, paler ( oloration, shape of the anal fin 
(which is not falcate, as it is in the young chinook salmon), and by the increased number and greater 
length of the gillrakers (about 37 gillrakers in the redfish and only about 23 in the chinocdc salmon). 
The young redfish 11 inches long has the following coloration: Back pale, with bluish tinge and 
25 to 30 rather large bluish-black spots, some of which are oblong and reach to or even cross the 
lateral line; median dorsal line dark; head dusted with dark points; lower half of side and l)elly 
pilaiu silvery white; iins nearly plain yellowish white, unspotted. A specimen 3 inches long, taken 
September 12, has the same general coloration, but the back is bluer and the spots have become large, 
oblong, vertical bluish bars, about 12 or 15 in number, 9 or 10 extending across the lateral line; the 
lower sides and belly yellowish silvery. 
8. Periodicity in the run of the bluehack salmon. 
The statistics of the lisheries of the lower Columbia, as well as other observations, show that the 
run of this species is large in the even years and small in the odd ones. The origin or meaning of 
this periodicity has never received an exilian atifui. Indeed, I do not know that the phenomenon has 
ever received the attention of any naturalist further than merely to note the fact. The fact is one of 
great interest, changing as it does the character of the fishery every two years, and the search for its 
explanation opens up a most attractive and promising field for investigation. We know too little 
about the migrations of this fish, particularl}" of its movements up and down the coast, to warrant us 
in bolding any decided views as to the origin of this interesting habit, if habit it may be called. An 
examination of the fisheries in other streams in which this species spawns may throw some light upon 
