I i C0< LBPA( r. B. 51 



ll<ih. On rocks, near low-water mark, and at a greater depth. 



i' niial. 



trlier writers this beautiful species was confounded 

 with N. cirrhosa t of which it was considered to be a luxu- 

 riant variety, and in 'English Botany' both are represented 

 on the same plate. Mr. Borrer was, 1 believe, its firsl de- 

 tector in this country, and I am indebted to him for one of 

 the original specimens, gathered at Beachy Head. From 

 N. cirrhosa it may always be known, by the differ 

 structure of the stem, the closer and more regularly pecti- 

 nated ramuli, and the greater size. In substance and 

 general habit, 8. plumosa has very much the appearance of 

 a Sertularia, and is almost as rigid. Jt appears to be pe- 

 culiarly a northern plant. 



70. cirrhosa {The hair-like Sphacelaria) j parasitical; filaments 

 naked at the base, short, densely tufted, Bimple or branched, 

 jointed throughout ; stem, or branches, pinnate j pinna? op- 

 posite, alternate, or irregular, of unequal Length ; utricles 

 ile or shortly Btalked, scattered, globose, Ag, Syst. Al<j. 

 p. 164. (Atlas, PL Will. Fig. 77.) 



Sphacelaria pennata, Lyngb. Ceramium cirrhosum, HooJc. Con- 

 ferva cirrhosa, Roth. C. intertexta, Both* 0. pennata, 



Ihnls. 



Hah. Parasitic on the smaller Alga?, between tide-marks. Peren- 

 nial ? Summer. Very common. 

 Here we have a very common and very variable j lant, 

 which puts on several distinct-looking forms, according 

 the locality in winch it may grow ; but, on a careful i 

 ruination of numerous specimens of these varieties now 

 before me, I cannot li\ on any characters which appear of 

 cific value. The species was once confounded with N. 

 plumosa, l>ut differs from thai beautiful plant in habii and 

 size, in its jointed main filaments, and in being tar less 

 regularly pectinato-pinnated, with proportionally shorter 

 pinnules. Being a very common plant, it was among the 

 firsl of the genus observed by botanists, and is figured in 

 the * Historia Muscorum' of 1 mIIcuius. under the specific 



name here preserved. 



77. fusca (The brown Sphacelaria) ; filaments densely tufted, 

 capillary, brown, distantly and irregularly branched ; 

 branches long and Bimple, bearing a few clavate or I 

 forked, minute ramuli ; articulations t\\ ice as Ion 

 marked by a transverse band ; Bpores globose, Ag. Sp. Alg, 

 I, p, 34. (Atlas, PL XVIII. Fig. 78.) 



