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THE AMERICAN NATURALIST [Vol. XL VI 



Fifth. Sexually mature fishes spawn without the 

 tubercles appearing, and in some cases frequently. 



Sixth. The effect of different waters, like those of the 

 sluggish warm lowland cedar-swamps where dark and 

 blackish, as contrasted with clear cold rapid upland 

 streams, does not seem to materially change the degree 

 of development. 



Seventh. Many species have the inner pectoral rays 

 furnished with tubercles, and these no doubt are of 

 assistance to the males in clasping the females during the 

 spawning operations. 1 



XVII, April 3^ 1903, g p. 531, and Bull. Bur. Fisheries, XXVIII, 1908, pp. 

 1111-1136, Pis. 94-120. 



