OF THE MARINE ALG1E. 97 



the Bryopsis species, of the Polysiphonias and Callithamnia, 

 nay, even the curious apices so characteristic of the genus 

 Ceramium, all. yield to this mode of treatment, especially if 

 it be aided by a hair pencil loaded with water and drawn 

 slowly among the .finer portions of the plant, should any 

 of them still continue to cling together. This operation 

 having been satisfactorily performed, the next thing is to 

 withdraw the water. Here the syringe again comes into 

 play, but this time as a suction pump. It is only necessary 

 to place its open end between the larger branches, and by 

 very slow movements of the piston the whole of the fluid 

 will be drawn up through the barrel, and can be discharged 

 into the plate. The eye will determine when the water has 

 been sufficiently abstracted, but the ear is' a still better 

 guide. As soon as a bubbling sound is heard in the body 

 of the instrument, it is a certain indication that air is taking 

 the place of the water, and that the latter is exhausted. 

 To empty the dish entirely it must be gently tilted on the 

 side which holds the root end of the plant, so that the 

 water shall flow towards the opposite side, where it may be 

 drawn off with the syringe. The water having been thus 

 got rid of, the operator will probably find it necessary to 

 give a final touch with a hair pencil to some of the branch - 

 lets or filaments that have been displaced, especially if 

 examples of the more delicate kinds be under treatment ; 

 the whole may then be lifted out of the dish and laid upon 

 blotting paper, to undergo a sort of preliminary drying. 



Although this process takes some time in describing, it 

 is in point of fact of the simplest kind, and allows of each 

 preparation being got ready in a very short space of time, 

 because the operator works upon a firm, even basis ; both 

 his hands are free, and there is no large quantity of water 

 to be displaced by a chance blow or shake, all which 

 advantages are wanting in the ordinary method of pre- 

 paring specimens in a plate or basin. 



The preparation must not be left too long exposed to 

 the action of the atmosphere, or it will be spoiled. The 



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