Z OF THE ALG^E GENERALLY. 



collector. It would be a mistake, therefore, to examine only 

 the larger masses of water ; for frequently the least impor- 

 tant localities afford the largest supply : indeed, certain 

 families (for instance the Scytonemacese and Nostochacese) 

 would be constantly overlooked, if the lowlier spots were 

 habitually neglected. In the same way a careful survey 

 of a half-dried pool or puddle will often give the richest 

 returns. 



The filamentous Alga? (such as the Confervacece, 

 Zygnemacece, and Vaucherice) are generally the first to 

 strike the attention of the collector, partly on account of 

 their mode of growth, in large tufted masses, and partly on 

 account of their bright green colour, so like that of the 

 Phanerogamia.* It is best, therefore, to make our first ac- 

 quaintance with these, and through them with the more 

 minute members of the order — the Diatomaceag, Desmi- 

 .diaceae, &c, numbers of which are generally to be found 

 adhering to the entangled tufts of their more gigantic 

 relations. The rest may be made out by degrees, as the 

 necessary amount of observation is given to them. 



To avoid needless repetitions, we will commence by 

 offering some suggestions which will be found useful. in 

 collecting these plants. As a general rule, the collector is 

 strongly advised to give his attention to everything that 

 can possibly be of the nature of an Alga ; for, without the 

 microscope, he will often be unable to decide what he has 

 before him. And if he is sometimes vexed at finding that 

 he has carried home some worthless object, he is at least as 

 likely to regret having thrown away from ignorance some- 

 thing of value. 



* Many members of the Zygnemaceous family are especially con- 

 spicuous, when viewed under the microscope or a good lens, on 

 account of the beautiful manner in which the cell contents are dis- 

 posed. Instead of forming a simple uniform ground colour, as is 

 usually the case, the chlorophyll, or green matter, is arranged in 

 spirals of exquisite pattern. In a few species the serpentine band is 

 solitary, but, generally speaking, there are from two to four spirals 

 interlacing and crossing each other at regular intervals. Figures 1 

 to 6, Plate i., will help to illustrate the above remarks. — Ed. 



