Ser. GONGYLOSPERME^. ( 193 ) Fam. CEUAJlIACEyE. 



CALLITHAMNION UOTKII.—Lpigb. 



Gen. Char, — Fronds filiform and articulated, sometimes at length in the older parts 

 cellular and partially opaque, single-tubed ; divisions mostly pinnate, dissepiments 

 hyaline. Fructification of two kinds, on distinct plants : 1. Favellse, mostly 

 lateral on the branches, and filled with minute spores ; 2. Tetraspores, external, 

 tripartite or cruciate. Name from waAJis, "beautiful," and Sajuros, "a shrub." 



Callithamnion Eothii. — Fronds very minute, densely tufted, forming 

 minute tufts or somewhat spreading strata, erect, sparingly branched ; 

 branches ii-regularly dichotomous, very erect and subcorymbose at the 

 summit ; ai'ticulations about twice as long as broad ; tetraspores clus- 

 tered on short subterminal ramvJi. 



Callithamnion Rothii. — Lyngh. Hyd. Dan. p. 129, t. 41 ; Arj. Syst. Alg. vol. ii. 

 p. 185 ; Harv. in Hooh. Br. Fl. vol. ii. p. 347 ; Wyatt, Alg. Damn. 

 No. 188; Endl. 3rd Suppl. p. 34; Kiitz. Phyc. Gen. p. 471 ; Harv. P.B. 

 plate 120 B. ; Harv, Man, p. 183; Harv, Syn. p'. 156; Atlas, plate 60, 

 fig. 278 ; Harv, N. B. A, part 2, p 242 ; /. G. Agardh, Sp. Gen, Alg, 

 vol. ii. p. 17. 



Ceramium Rothii. — Berh. Gl. Br, Alg. t. 20. 



Trentepohlia Rothii. — Harv. in Moxh. Fl. Hib. part 3, p. 218. 



Conferva Rothii. — Linn. Syst. Nat. vol. vi. p. 1806 ; Dillw. Conf. t. 73 ; E. Bot, 

 t. 1702 ; Jv/rg, Alg. Dec. No. 10. 



Conferva violacea. — Roth, Cat. Bot. vol. i. p. 190, t. 4, f. 1 ; Fl. Germ. vol. iii. 

 part 1, p. 525. 



Var. /3. 2^urpurea, — Filaments veiy minute, slightly branched, forming 

 small velvet-like patches. 

 Callithamnion purpureum. — Harv. Man. 1st ed. p. 116. 



Trentepohlia furpurea. — Ag. Syst. p. 36 ; Harv. in. Hook. Br. Fl. vol. ii. p. 382 ; 

 Harv. in Mack. Fl. Hib. part 3, p. 218. 



Brssus purpureum.— F. Bot. t. 192. 



Conferva purpurea. — Dillw. t. 43. 



Callithamnion Rothii, ^purpureum. — Harv, P. B, descrip. plate 120 b. ; Harv. 

 Man. p. 183; Harv. Syn. p. 156; /. G. Agardh, Sj). Gen. Alg. 

 vol. ii. p. 18 ; Harv. N. B. A. part 2, p. 242. 



Hab. — On the surface of rocks from about half-tide level. j3, on rocks within the 

 reach of the spray, but not of ordinary tides. Perennial. Winter. Common. 



Geogr. DisT. — Atlantic shores of Europe ; Baltic Sea ; east coast of North America. 



Description'. — Fronds minute, forming minute densely pulvinate 

 tufts, or by afterwards becoming confluent, moi-e or less widely- sprcadino- 



VOL. II. c (3 



