768 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



craw-fish than the latter. In tolerably warm water the eggs begin to ap- 

 pear in January, and the young fry* in March. These craw-fish do not, 

 as a general rule, grow very large, for they scarcely reach a length of 10 

 centimeters even at the age of fifteen. By way of experiment I have 

 placed them in other water, e. g., in my craw-fish box in the river Oder, 

 but they did not grow. Such craw-fish, which are generally of a light 

 green color, are not suited for transportation, as they are very apt to die 

 when carried any distance. Lakes like those above described are gen- 

 erally overcrowded with craw-fish. The finest and largest craw-fish are 

 found in rivers, especially small ones, where boats cannot pass, and 

 where the craw-fish are not disturbed by manufacturing establishments, 

 ,e. #., the Eilang, the Obra, &c. In such waters the craw-fish develop 

 very rapidly, but cannot be used as ■• soup craw-fish" till they are four 

 to five years old. 



The worst enemy of the craw-fish is the eel. It may truly be said that 

 whenever a river or lake contains many craw-fish there will be no eels, 

 and wherever there are no craw-fish the eels will be numerous. The fa- 

 vorite food of the eel is one-year-old craw-fish, and they but rarely eat 

 larger ones. 



The craw-fish themselves, however, are bloodthirsty and voracious 

 feeders. As soon as dusk sets in they grow lively and move back- 

 wards and forwards with great agility; they swim well, and their 

 sense of sight is very keen. When a craw-fish has eyed its prey, it 

 sneaks up to it and with one bold dash impales the little fish or 

 frog on its " tusk," the long, pointed, horn-like excrescence found be- 

 tween the eyes. As soon as it has secured its prey, it goes to the bot- 

 tom of the water and devours it, holding it firmly with its two claws. 

 It has been said that the craw-fish will also eat putrefied meat, but this 

 is a disputed point. It will take such meat as it takes pieces of wood 

 and stone, merely to cover itself. When kept imprisoned it lives on 

 fish, meat, turnips, bread, potatoes, &c, but a craw-fish will never seek 

 as food a putrefying animal body, especially if its odor is offensive. 

 One may easily convince himself of this, if in catching craw-fish two 

 nets of equal size and kind are employed, the one baited with fresh 

 fish, the other with decaying fish emitting a strong odor, and are placed 

 in the water not far from each other. The result will be, that the one 

 net will soon have some craw-fish in it, whilst the other will remain 

 empty. 



The most common and mqst profitable way of catching craw-fish 

 is with the so-called " Bolljacken." These consist of two hoops each, 

 with a tube-shaped net attached. On the outside the two hoops are 

 covered with a net-work, and the whole apparatus has the appear- 

 ance of a cylinder. The hoops are kept open by wooden pegs, a piece 

 of fresh fish or a frog is put inside as a bait, a stone is tied to it, and thus 

 the "Bolljacken" is let down to the bottom. 



Another apparatus for catching craw-fish is the so-called "Teller- 

 hamen," a sort of purse-net, — a hoop covered with a net, in the middle 



