RHODOMBLACE^. 91 



two feet higb, divided into long, simple branches, -wbich 

 are thickly clothed with slender, much divided, irregular 

 branchlets. Spores in ovate conceptacles on the summer 

 branchlets ; tetraspores in the substance of the tips of the 

 winter branchlets. 



The summer and winter states of this plant are so 

 different that they may be easily mistaken for two spe- 

 cies. In the former the side branches are from one to 

 three inches, or more, long, and furnished with numer- 

 ous, slender, much divided branchlets ; in the latter 

 they are simple, or only slightly divided, and seldom 

 more than half an inch long, The colour of the plant 

 when growing is a dark red, which changes to black 

 in drying. This property is common to all the species 

 of the genus, and hence the appropriate name of red- 

 black. 



Rhodomela subfusca. Brown Rhodomela. 



Fronds tufted, much branched, from six inches to a foot 

 long, cartilaginous, rigid ; branches irregularly divided, the 

 first series alternate, the second twice pinnate, the third 

 furnished, below with simple, alternate, rather distant, awl- 

 shaped branchlets, above with more divided branchlets, 

 which are densely crowded at the ends of the branches. 

 Spores in ovate, very short-stalked conceptacles; tetraspores 

 arranged in pairs, or singly in the awl-shaped, terminal 

 branchlets. 



This species is common all round our coasts. Like 

 the last, it has two very distinct states. In summer it 

 appears in all the perfection of parts described above. In 

 winter only a few almost naked stems are to be found ; 

 but as these frequently bear accessory stichidia contain- 



