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THE AMEBIC AN NATURALIST [Vol. LI 



Professor Meek hardly does justice to the spawning habits of 

 the red or blueback salmon. It runs up rivers to varying dis- 

 tances — from one mile to 1,500 miles (Lake Labarge on the 

 Yukon). But it never enters a stream which does not flow from 

 a lake and it spawns always in the small streams at the head of 

 the lake. 



At Boca de Quadra in Alaska, the small stream is barely a mile 

 long. It comes from a clear lake, perhaps five miles long. Into 

 this stream and lake the salmon crowd by the thousands. The 

 Yukon is not a good red salmon stream, because the nearest tribu- 

 tary lake, Labarge, is about 1,500 miles from the sea. Yet red 

 salmon enter the river and reach the lake. In streams without 

 lakes as the Skagway, red salmon are never seen. The King 

 salmon {Oncorhynchus tschamjtscha) also runs for great dis- 

 tances, but it is absolutely indifferent to the presence of lakes. 

 It is probable that the red salmon spend their first winter in the 

 lake and some never leave it, remain landlocked and dwarf until 

 spawning time (usually four years). 



One of the most difficult of problems is to understand the in- 

 stinct of the red salmon. Every individual of this and of each of 

 the other species of Pacific salmon (Oncorhynchus) dies after 

 spawning. How does the spawning fish, stupid in most regards, 

 know when it enters a river that there is a lake before it? How 

 does it come to avoid all lakeless tributaries as it goes up, finally 

 reaching the lake's head and the brooks that feed it? And why 

 do the other salmon species totally lack this instinct 1 There are 

 other problems, yet unsettled, regarding the supposed homing 

 instincts of salmon. The majority (but not all) seem to return 

 to spawn to the parent stream which they left as fingerlings. 

 Why not all ? And why any ? 



The recognition of the age of salmon and trout by the adjust- 

 ment of the rings on the scales, as recently worked out by Dr. 

 C. H. Gilbert and others, received full attention from Professor 

 Meek. The scales of the salmon are marked by concentric rings 

 of growth, and these are more widely separated in the summer, 

 the feeding time of the salmon when the individual grows most 

 rapidly. 



Professor Meek devotes much space to the singular breeding 

 habits of the eel, which spawns in the. sea, entering rivers to feed. 

 But many individuals, in our Mississippi Valley never descend 

 to the sea. A very large eel, once taken by the present reviewer, 

 above the Cumberland Falls in Kentucky, 2,000 miles from the 



