THE HISTORY OF FISH CULTURE. 555 



EUROPEAN SPECIES. 



3fal€. Female. 



The salmou, {Salmo salar.) with The river-trout, {Salmo fario.) 



Do., do. do. The lake-trout, {Salmo lacustris.) 



Do., do. do. The ombre chevalier, [Salmo um- 



hla.) 

 (?) Omhre chevalier, {Salmo umbla.) do. The salmou, {Salmo salar.) 

 The river-trout, {Salmo fario.) do. Do., do. 



Do., do. do. The omhre chevalier, {Salmo um- 



bla.) 

 Theombre chevalier, {Salmo umbla.) do. The river-trout, (Salmo fario.) 

 The lake-trout, {Salmo lacustris.) do. The salmou, {Salmo salar.) 



AMERICAN SPECIES. 



The \vh\te-&sh, {Coregonus albns.) The salmou-trout, {Salmo namay- 



cush.) 

 The alewife, {Pomolobus pseudo-ha- The shad, {Alosa sapidissima.) 

 rengus.) 



The advances made iu the art of fish-culture by its adoption in this 

 country are now extended by its application to a number of uew^ species. 



In the family of Clupeidw nothing seems to have been attempted iu 

 Europe, while in America the culture of the shad {Alosa sapidissima) is 

 one of the most extensive and successful efforts iu fish-culture, and that 

 of the alewife {Pomolobus pseudo-harengus) has been experimented upon 

 with success. 



In the genera of Salmo, Coregonus, and Thymallus there is entire simi- 

 larity of condition between American and European species, though the 

 species are different, except in the case of Salmo salar. 



In apparatus there are several advances. Though iu considering 

 the shad-box (see plate) we find the floating-box with wire-gauze iu use 

 iu the old world for years,* still its inclination to the current, iu the 

 manner of Seth Green's patent, is an improvement in producing a com- 

 plete and continuous circulation of water. 



The tray methods of Holton, of Clark, and of Williamson (see plates) 

 are of great importance iu economy of space, in the facility for manipu- 

 lation of the eggs, and, in saving of expense, because smaller buildings are 

 sufficient for the accommodation of apparatus, and from the compact- 

 ness of the apparatus more labor can be accomplished than with the ex- 

 tended trough method. 



Improvements in egg-carriers and in vessels for transporting young 

 fishes have been referred to on another page. 



The adv^ance made in methods of impregnation and care of ava 

 are the results of continued experience aud study. The so called dry 



*See Volt's Essay ou Fish-Culture. Translation in Report on the Artiticial Propa- 

 gation of Fish, by G. P. Marsh, Burlington, Vt. Page 41. 



