136 REPORT OF THE COMMISSIONERS OF 



Lake in British Columbia he recognized its distinctness from other species, and 

 described it as new under the name Oncorhynchus kamloops, afterward changed to 

 Salmo kamloops. He now considers the No Shee, Kern River, Shasta, Mason's and 

 golden trouts as varieties of the rainbow. 



Common Names. — In New York it is frequently mentioned in the Reports of the 

 Fish Commission as the California mountain trout. In California it is the brook trout 

 or speckled trout, but will now be distinguished in some way from the brook trout 

 introduced from the East. The name rainbow trout springs naturally from the 

 specific appellation irideiis, and is the one generally adopted in the United States and 

 on the Continent of Europe, where the species is now acclimatized ; this has been 

 translated into regen-bogen forclle by the Germans and truite arc-en-ciel by the French. 



DISTRIBUTION. — The species ranges from California, near the Mexican boundary, 

 to southern Alaska. A small example was taken at Sitka in 1880 by Captain (now 

 Rear-Admiral) Lester A. Beardslee, U. S. N. It is found chiefly in mountain streams 

 west of the Sierra Nevadas, rarely descending into the lower stretches of the river, but 

 occasionally does so and passes out to sea. 



In Pennsylvania it was extensively introduced, but with such imperfect results at 

 first that the attempt to acclimate it in the State was given up for some years. The 

 species, however, has reproduced naturally in Cumberland County and in Mill Creek, 

 in Pike County, as well as in some other streams, so the work of stocking waters with 

 rainbows was resumed. 



The artificial distribution of the species has been wide and it has succeeded beyond 

 all expectation in numerous localities. Favorite States for the rainbow are Wisconsin, 

 Michigan, Missouri, Colorado and North Carolina. In Missouri its growth is remark- 

 able, at the Neosho station of the United States Fish Commission averaging about one 

 inch per month up to the age of one year. 



Size. — The average length of individuals of this trout is less than one foot, but 

 specimens measuring two feet and weighing eight pounds have been recorded. The 

 Neosho station had rainbows nearly one foot long at the age of one year. The largest 

 recorded example was reared by Mr. C. G. Atkins at Craig Brook, Me. At five years 

 of age it weighed fifteen pounds. 



In Japan, where the species was introduced from California in 1877, rainbows were 

 sexually mature when three years old and averaged nineteen inches in length. In France 

 the limit of length of three year old fish was two feet according to Dr. Bellesme. 



Habits and Reproduction. — In its native waters the rainbow feeds on worms, 

 insect larvae and salmon eggs. In streams in which it lives associated with the quinnat 

 salmon it is the most destructive enemy of the eggs of that fish. Spawning occurs in 

 winter and early spring, varying with temperature and locality. The bulk of the eggs 



