- 960 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [18] 
the lower tile is about six inches above it. Each of these clusters of 
tiles bears the name of ‘bouquet’ or ‘mushroom.’” 
Tiles arranged in, ‘‘ bouquets.”.—In the principal breeding parks of the 
river Trinité, they have settled upon the use of tiles arranged in “ bou- 
quets,” as represented in our design. At Morbihan this is also con- 
sidered a very rational system. It has this great advantage, that the 
apparatus can be entirely prepared on land and so arranged that the 
setting up will consume but a very short space of time. 
This is an excellent idea, as will be understood from what has already 
been said, and the details we have given concerning the deposition of 
sediment will indicate its bearings. 
Whenever, in a river, subject to depositions of sediment, the nature of 
the bottom is modified, if: only by a wooden stake, a deposit of mud is 
induced, which elevates the level of the bottom. One will gain some 
idea of the rapidity with which the deposit of sediment is formed, on 
learning that, in the military port of Lorient, after the alterations which 
modified the bottom, the deposition reached a depth of from twenty to 
Fia. 2. Fie. 3. 
Frames for supporting ‘‘Bouquet’’ collectors on a hard bottom. 
twenty-eight inches a year, the average being twelve inches. In the 
commercial port the case is identical, and several spells of bad weather, 
accompanied by a southwest wind, are sufficient to produce the muddy 
deposit. Culturists should not forget that the water is not charged with 
sediment, excepting when itis agitated. At such times, the waves wash- 
ing upon the muddy shores become charged with mud, which is de- 
posited at those points where the equilibrium of the bed has been modi- 
fied, in one way or another. 
The cluster of tiles fastened to a stake, if arranged above the muddy 
bed of a river in July, has been placed at the proper season, and from 
