564 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [26] 



At the present time two varieties of the Salvelinus are cultivated, 

 namely, the Salmo (or Salvelinus) unibla, and the Salmo (or Salvelinus) 

 fontinalis. The second variety may now be considered acclimatized at 

 Huningen, Apeldoorn, Berneucben, and in many other establishments. 

 The Salmo fontinalis is a great favorite, not only on account of its rapid 

 development, but also on account of the extraordinary beauty of its 

 coloring. 



The spawning season of the Thymallus vexillifer had not yet begun, 

 and I could not, therefore, witness the hatching of the eggs of this fish ; 

 which, however, is raised in many establishments. Mr. Eckardt, for 

 instance, keeps them in a special paved pond. 



The alimentary value of the Coregoni is sufficiently known; audi 

 therefore deem it proper to devote a few lines to this fish, all the more 

 as experiments are being made to introduce it in Italy, where it is not 

 found. But also in countries where this fish is found attempts are made 

 to introduce new varieties, such as the American Coregonus albus, which 

 is cultivated at Zurich, Liibbincheu, and Berneucben. 



The Radolfszell establishment, situated on the shores of the Lake of 

 Constance, gives special attention to the Blauf el chen or Coregonus wart- 

 manni. There are several varieties of this fish ; and the Radolfszell es- 

 tablishment knows of at least three, differing from each other not only 

 by bodily characteristics, but also by their geographical distribution. 

 These are the Blaufelelien, found in the Lake of Constance proper ; the 

 Silberfelcken, in the Untersee (connected with the Lake of Constance), 

 aud the GanjlscJi, found only in a certain limited portion of the lake. 

 The Coregoni at Selzenhof come, as may be supposed, from the Lake of 

 Constance. From this same lake came the Coregoni, hatched at Hii- 

 ningen, which have been sent to the Italian Government for the Lake of 

 Como, where they find the required food, as that lake contains the 

 pelagic crustaceans, which, as Dr. Asper, of Zurich, has already de- 

 clared, are an indispensable article of food for this fish. 



Mr. Eckardt does not think that there is any specific difference be- 

 tween the Coregonus marama and the Coregonus tcartmanni, and bases 

 this opinion on the reciprocal fecundation of the sexual products of these 

 two varieties. Notwithstanding the fact that such fecundation has 

 actually been observed — proving that even cross-breeds may possess 

 the .faculty of fecundation — this would not form a very strong proof in 

 favor of Mr. Eekarclt's opinion. 



Two conditions are essential to the existence of Coregoni, namely, 

 great depth of water and suitable food (insects). Nevertheless it is 

 possible, according to Mr. Schuster's statement, to introduce the Core- 

 gonus /era also in shallow water, provided it contains suitable food. 



The production of hybrids of salmonoids also forms part of the work 

 of fish-culture, and has been done on a sufficiently large scale. The 

 salmon, the Salvelinus umbla, and the American trout will interbreed 

 with the trout. 



