98 PISCICULTURE IN GERMANY. [CHAP. in. 



As soon as the piscicultural system "became known, it 

 was rapidly extended over the whole continent of Europe, 

 and the rivers of Germany were among the first to participate 

 in the advantages of the artificial system. In particular may 

 be noticed the efforts made to increase the supplies of the 

 Danube salmon, a beautiful and excellent food-fish, with a 

 body similar to the trout, but still more shapely and graceful, 

 and which, if allowed time, is said to grow to an enormous 

 size. The young salmon of the Danube are always of a darker 

 colour than those a little older, but they become lighter in 

 colour as they progress in years. The mouth of this fish is 

 furnished with very strong teeth ; its back is of a reddish 

 grey, its sides and belly perfectly white ; the fins are bluish 

 white ; the back and the upper part of both sides are slightly 

 and irregularly speckled with black and roundish red spots. 

 This fish is also very prolific. Professor Wimmer of Land- 

 shut, the authorities at Huningue mentioned, had frequently 

 obtained as many as 40,000 eggs from a female specimen 

 which weighed only eighteen pounds. Our own Salmo solar 

 is not so fecund, it being well understood that a thousand 

 eggs per pound weight is about the average spawning power 

 of the British salmon. The ova of the Danube salmon are 

 hatched in half the time that our salmon eggs require for 

 incubation viz. in fifty-six days while the young fry attain 

 the weight of one pound in the first year ; and by the third 

 year, if well supplied with the requisite quantity of food, they 

 will have attained a weight of four pounds. The divisions of 

 growth, as compared witJi Salmo solar, are pretty nearly as 

 follows : That fish, curiously enough, may at the end of two 

 years be eight pounds in weight, or it may not be half that 

 number of ounces. One batch of a salmon hatching go to 

 the sea at the end of the first year, and rapidly return as 

 grilse, handsome four-pound fish, whilst the other moiety 

 remain in the fresh water till the expiry of the second year 



