APPENDIX. 249 



these seductive announcements were made, without having 

 yet furnished brillant results. 



" Among fishes, some, as the salmon, deposit their ova in 

 slight excavations, in gravel, or in the interstices between 

 stones; others, as the perches, and cyprinids (carp, bream, 

 roach, &c.), attach their ova, agglutinated together by 

 means of a viscid matter, to aquatic plants, stones, or any 

 bodies to which their eggs can be fixed. It is especially 

 for the last that artificial spawning-beds might sometimes 

 be advantageously prepared. 



" The construction of an artificial spawning-bed is a very 

 simple matter. A framework of sticks or laths should be 

 made, and to such framework, boughs, furze, and aquatic 

 plants should be fastened by cords, in such a way as to 

 form irregular structures. It is also easy to give to struc- 

 tures of this kind a circular form, by taking hoops for 

 frameworks. The form, and especially the size to be given 

 to these spawning-beds, would necessarily vary, according 

 to the character or the size of the body of water in which 

 they are to be immersed. They should be held to the bot- 

 tom of the water by stones, and fastened to a stake or post 

 on the bank. When kept in place in this way they can be 

 easily drawn out of the water, if it becomes necessary to 

 do so. 



" It will be readily understood that these artificial spawn- 

 ing-beds will be especially serviceable in those streams and 

 canals which are so clear as to be devoid of any natural 

 spawning-beds. 



" For the salmonids, which spawn on a gravelly bottom, 

 and whose ova remain free, artificial spawning-places are 

 very simple and readily prepared. It is only requisite to 

 cover in certain places the beds of rather shallow and rapid 

 streams, near the bank or the bottom of rivulets, with a 

 thick layer of gravel or pebbles, and to prepare slight ex- 



