BED SEAWEEDS 



IN Rhodophycese, known also as Florideae and Rhodospermese, 

 algae attain their highest development, "this is marked by 

 the mode of reproduction, which, more nearly than in the other 

 subclasses, resembles that of flowering plants. The fronds, how- 

 ever, are not as large and do not as closely resemble stem and leaf 

 as do some species of the brown algae. 



The species of this subclass are very numerous, and the variety 

 in their fronds, their delicate texture, and their colors, which vary 

 from pink to purple, make them the most attractive of the sea- 

 weeds. They grow mostly in deep water, but are often found 

 washed ashore, and many grow just below low-water mark and 

 on the shady side of tide-pools. 



In the simplest species the frond consists of branched cell-rows. 

 In some of these the filaments are so fine that a pocket-lens is re- 

 quired to determine the differences in branching and fully to 

 appreciate the beauty of the plant (Callithamnion). Some have a 

 cell-surface. In Delesseria the membrane assumes the outline of 

 a foliage-leaf. Dasya, which is an abundant variety, is especially 

 beautiful in its feather-like appearance. The corallines are sin- 

 gular in that they are incrusted with lime and resemble corals. 



ORDER NEMALIONACE.2E 



SUBORDER HELMINTHOCLADIEE 



GENUS Nemalion 

 The threadweeds. 



N. miiltifidum. Frond six to twelve inches long, cylindrical, solid, 

 cord-like, elastic, tough, shiny, very gelatinous ; branches repeatedly in 



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