Ser. GONGYLOSPERME/E. ( 169 ) Fam. CERAMIACEiE. 



Plate CXXIV. 

 CALLITHAMNION KOOKEm.—Ag. 



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 Ka\hs, "beautiful," and 6d/xi/os, "a shrub." 



Callithamnion Hooheri. — Stem rathei' slender, tapering and per- 

 cuiTent, the ai-ticulations rendered obsolete near the base by longitudinal 

 veins, distinctly apparent upwards, somewhat alternately iDranched ; the 

 branches simple or again divided, all naked below, bi-tripinnated 

 vipwards ; pinnae and pinnules rather patent ; articulations from one and 

 a-half to two and a-half times as long as broad. 



Callithamnion Hookeri. — Ag. Sp. Alg. vol. ii. p. 179 ; Harv. in Hooh. Br. Fl. 

 vol. ii. p. 341 ; Harv. P. B. plate 279 ; Harv. Man. p. 176 ; Harv. 

 Syn. p. 148 ; Atlas, plate 58, fig. 266 ; /. G. Agardh, Sp. Gen. Alg. 

 vol. ii. p. 51. 



Callithamnion lanosum. — Harv. in Hook. Br. Fl. vol, ii. p. 341 ; Wyatt, Alg. 

 Damn. No. 139. 



Callithamnion spinosum. — Harv. in Hook. Br. Fl. vol. ii. p. 345 ; Harv. Man. 



1st ed. p. 111. 

 Phlebothamnion Hookeri. — Kiltz. Phyc. p. 375 ; 82'). Alg. p. 653. 

 Phlebothamnion spinosum. — Kiitz. ^. Alg. p. 653. 

 Ceramium Hookeri.— Ag. Syn. p. 27 ; Hook. Fl. Scot, part 2, p. 85 ; Ag. Sysf. 



p. 138. 

 Conferva Hookeri. — Hillw. Conf. t. 106. 



Hab. On Algse, and on rocks between tide-marks, and in deep water. Annual. 



Summer. Common. 



Gkogr. Dist. — Atlantic shores of Europe. 



Description. — Root, a minute conical disc. Fronds densely tufted, 

 one to three inches or more in length, very slender, and slightly tapering, 

 much branched ; branches somewhat scattered or alternate, rather 

 patent, once or twice again branched in a more or less distichously 

 pinnate or bipinnate manner upwards, the bases generally naked for 

 about one-third ; all the divisions more or less patent, the ultimate 

 pinnae often recurved. Articulations from one and a-half to two and 

 vol. ii. z 



