MODE OF PROCURING SPECIMENS. 69 



is hardly inferior to the preceding plant in value 

 to the aquarium-keeper, and flourishes wonder- 

 fully. P, vulgaris may be used for the same 

 purpose. I have seen one of these plants in an 

 aquarium, which had increased to such an enor- 

 mous size, that it was aptly compared by a 

 bystander to a lady's purple silk apron. 



The ulva and porphyra, if intended to bo 

 eaten, must be gathered in the winter, or, at all 

 events, the very earliest of the spring months. 

 The purple laver is said to be much superior 

 to its green companion, but I cannot speak 

 from personal experience. If any of my readers 

 would like to try the experiment for themselves, 

 they may easily do so ; the laver should 

 be stewed for several hours, until it is reduced 

 to a pulpy mass, which, with the addition of 

 lemon juice, is considered by some persons a 

 dainty. 



I may here mention tkat, although both ulva 

 and porphyra will live in an aquarium, when 

 floating freely through the water without any 

 attachment, yet it is better that they should be 

 adherent to some stone or shell, by which they 

 can be anchored in a convenient spot. Now theso 

 plants are very constant, for they never have 

 but one attachment during their whole lives^, 



