PRESERVATION OF SPECIMENS. 71 



dredge. It will live well enough in an aqua- 

 rium, and gives a decided character to that 

 portion of the tank in which it is placed. Again, 

 when dried, it is largely manufactured into bed- 

 stuffing, under the name of Alva, and is used 

 instead of hay or straw for packing glass, china, 

 and other fragile wares. On many coasts this 

 plant is known by the name of Grass-wrack, 

 and is cast up in great quantities on the shore, 

 where it soon turns black, rots, and presents a 

 very unsightly aspect. 



If the naturalist wishes to dry and preserve the 

 algae which he finds, he may generally do so 

 without much difficulty, although some plants 

 give much more trouble than others. It is neces- 

 sary that they should be well washed in fresh 

 water, in order to get rid of the salt, which 

 being deliquescent, would attract the moisture 

 on a damp day, or in a damp situation, and soon 

 ruin the entire collection. When they are 

 thoroughly washed the finest specimens should 

 be separated from the rest, and placed in a wide 

 shallow vessel, filled with clean fresh water. 

 Portions of white card, cut to the requisite size, 

 should then be slipped under the specimens, 

 which can be readily arranged as they float over 

 the immersed card. The fingers alone ought to 



