REPORT OF COMMISSIONER OF FISH AND FISHERIES. XXVII 



United States are equally adapted for the production and growth of this 

 species. 



On the Atlantic slope, there are few if any rivers as turbid as the Sac- 

 ramento ; few which have not spring sources iu the Appalachian range, 

 aud among their tributaries many rapids, pools, and eddies, in rocky and 

 gravelly places, suitable for spawning-grounds. Of the rivers of the 

 Gulf States, the Chattahoochee and the Alabama have their sources in 

 the southern slopes of the Blue Eidge, among cool, spring-fed brooks. 

 They rise among hills and rocks in a country full of large springs. The 

 Brazos and Colorado Bivers, of Ttxas, have their sources among the 

 springs of the southern hills and spurs of the Bocky Mountains, and the 

 Guadalupe and San Antonio Bivers are fed by large springs. Most of 

 the Texas streams are turbid, but not more so thau the Sacramento or 

 San Joaquin. 



The suggestion that the salmon are not likely to find suitably cold 

 waters after descending to the sea, the following facts show to be 

 groundless. 



The temperatures of the bottom of the Gulf of Mexico have been 

 recorded* through a series of lines extending from the lougitude of 

 the mouth of the Mississippi to the Tortugas and Key West, Fla., and 

 temperatures found equally as cold as those off the coast of Massachu- 

 setts aud New England. As low as 34° Fahrenheit has been observed 

 at a depth of 896 fathoms ; at depths of 421, 610, aud 790 fathoms, 35° 

 and 3G° were observed, while 40°, 41°, and 42° were common at from 400 

 to over 1,800 fathoms, and 50° to 60° between less than 100 to 400 

 fathoms and more. 



The only peculiarity especially notable in the streams to which the 

 California salmon belong is that they are snow-fed during most of the 

 year. As, however, the Maine salmon, a species much more sensitive 

 to heat than that of California, inhabits rivers not snow-fed, and more- 

 over is kept in the Bucksport breeding-pond throughout the entire sum- 

 mer at a temperature of 70°, we have a sufficient guarantee that the 

 California fish will not be affected in its transfer; indeed, the whole 

 question is one relating to the rapidity of development of the eggs, rather 

 than to the conditions surrounding the fish ; the warmer the water the 

 more rapid and premature the birth of the embryo. 



Thus far we have left entirely out of consideration the great system 

 of waters contributing to the Mississippi Biver. The main stream ex- 

 tends from latitude 47° 50' to 29°, and the northernmost tributary of 

 the Missouri as far north as 50°. Its greatest length is 2,616 miles,t 

 from its highest source to the Gulf. From the source of the Madison 

 Fork, the formerly-supposed head of the Missouri, (within the National 

 Yellowstone Park,) to the Gulf, it has a length of 4,194 miles.t 



* Coast Survey reports. 



t See measurements iu tables on page 91 of the Physics and Hydraulics of the Missis- 

 sippi River. Uuited States Engineer Bureau. 



