AME'^ICAN FISHES IN AUSTRIA. 981 



Not less valued than the rainbow trout was the American brook char, Sal- 

 ■velinus lontinalis. It is true it was less utilized than the irideus, as it can only- 

 live in spring water; its breeding gave very satisfactory results, however, in the 

 first years after its introduction. Not inferior to the irideus as regards early 

 growth, it behaved excellently even in ponds watered exclusively by precipitation 

 of the atmosphere and it appeared as though the brook char might be qualified to 

 replace our brook trout, whose breeding offers far greater difficulties. In the 

 course of time, however, these sanguine expectations gave place to bitter disap- 

 pointment, and it became obvious that all the hopes entertained were chimerical. 



Even before birth the char causes great trouble. The losses in eggs are enor- 

 mous, as despite scrupulous attention at spawning time the number of sterile 

 eggs is great beyond measure, and miscarriages are far more frequent than with 

 other fish. On the other hand, it is true that the bringing-up of the brood gives 

 very little trouble. The small fish take artificial food very early and in autumn 

 the pond is alive with fry. But soon an unpleasant feature becomes visible, viz, 

 premature growth, which attribute is the more unfortunate as the char indulges 

 in cannibalism more than any other fish. In this respect it comes very near the 

 pike. Its voracity very greatly promotes its growth in the first and second 

 years, but later it suddenly stops growing and fine large fish are seldom seen. 



Its capacity to resist disease, which quality we value so highly in the 

 irideus, is extremely small. Bacterial infections, fungus, and intestinal disorders 

 often kill whole stocks, and it is also much more liable to furunculosis than is its 

 American brother. Besides, the char suffers from a peculiarly special form of 

 petechial affection. This manifests itself in irregularly shaped flat defects of the 

 surface skin, dull gray spots with byssus, the origin of which has not yet been 

 definitely ascertained. This disease has discouraged many pisciculturists from 

 continuing to breed the fontinalis. 



Another circumstance must be mentioned which makes the cultivation of 

 the brook char in the second year very unprofitable, namely, degeneration of the 

 eggs caused by overfeeding. That the brood product of such fish as are 

 artificially fed is entirely worthless would be a lesser evil were it not also that 

 the fish themselves perish in great numbers at the spawning time through over- 

 fattening of the internal organs. It is chiefly the spawners that die, as they can 

 not deposit their spawn, which is not thoroughly and normally matured. The 

 char, moreover, requires special qualities and temperature of water. It only 

 thrives in hard, clear spring water of even temperature ranging from 42° to 54° F. 

 The risk connected with its fattening rapidly increases with rising temperature 

 of water, whilst if this is much below the above-mentioned degrees the food taken 

 no longer affords proper nourishment. It has often been proposed to rear the 

 char in running water, iDut to this the objection must be made that the char 

 would immediately become too formidable a competitor of our brook trout with 



