136 



Aquatic Organisms 



recognizable by the swollen or nodulose appearance of 

 the ultimate (fruiting) branches. Chantransia is a 

 beautiful purplish-brown, extensively branching form 

 that is more widely distributed. It is common in clear 

 flowing streams . It much resembles Cladophora in man- 

 ner of growth but is at once distinguished by its color. 



FIG. 54. Red and brown algae (after West). 

 a, Lemanea; b, Chantransia; c, Batrachospermum; d, Hydrurus. 



Batrachospermum is a freshwater form of wide distri- 

 bution, with a preference for spring brooks, though occur- 

 ring in any water that is not stagnant. It grows in 

 branching filaments often several inches long, enveloped 

 in a thick coat of soft transparent mucus. The color is 

 bluish or yellowish-green, dirty yellow or brownish. 

 Attached to some stick or stone in a rivulet its sprays, of 

 more than frond-like delicacy, float freely in the water. 



Hydrurus grows in branched colonies embedded in a 

 tough mucilage, attached to rocks in cold mountain 

 streams. The colonies are often several inches long. 

 Their color is olive green. They have a plumose 

 appearance, and are of very graceful outline. 



