134 Dzvc/lers of I he Sea and Shore 



But he need not depend on the chance of the waves 

 to start his acquaintance with this interesting group; 

 an abundance of living forms will be found growing 

 well within his reach. Of the genus Polysiphonia alone, 

 there are over two hundred named species. If it so 

 happens that he is fortunate enough to possess a micro- 

 scope, some startling revelations await him in the exam- 

 ination of the structures of these threadlike plants. 

 Under that instrument a filament becomes a bundle 

 of filaments, or tubes, surrounding a central tube. 

 These tubular parts are called siphons, and from them 

 Polysiphonia (meaning "many tubes") gets its name. 

 In some species the siphons are bare, and the filaments 

 are banded with alternate rings of color. In others, a 

 surrounding layer of corticating or bark cells cover the 

 siphons, giving the filament an unmarked, uniform, but, 

 nevertheless, attractive appearance. 



Then there is Ceramhim, the pitcher weed. This 

 also shows to its best advantage under the microscope. 

 Like Polysiphonia, it is banded, but its forked filaments 

 are not made up of siphons. Another is Cailithamnion, 

 a soft, silky seaweed of cobweb fineness. This plant, 

 too, is represented by many species; they grow in crim- 

 son tufts, and along each gauzy filament are dense dots 

 of deep red. 



However, the want of a microscope should not deter 

 the ambitious beginner; a good, strong pocket lens will 

 often serve him well. I shall add, moreover, that even 

 the latter could be dispensed with, and there would still 

 remain a numerous host whose obvious details would 

 not fail to excite his wonder and delight. 



Notwithstandinji that the red seaweeds are found in 



