284 



Fig. 283. Bryoihamnion trique- 



tru/it (Gmel.) Howe. Part of a 



plant. (About 3:1). 



rather deep water at a depth of 20 

 meters or more. The plants taken 

 from deep water are slender and are 

 not much ramified, those from shal- 

 low water are more robust and richly 

 ramified. 



This species is rather common along 

 the shores of the islands. 



Geogr. Distrib.: West Indies, Bra- 

 zil, Atlantic coast of Africa. 



Bryothamnion Seaforthii (Turn.) Kiitz. 



KUTZING, Phycologia gener., p. 433, 

 tab. 52, fig. 11; Spec. Alg., p. 842. AGARDH S 

 J., Spec. Alg., vol. IL pars III, p. 848. 

 FALKENBERG, P., Rhodomelaceen, p. 174, 

 tab. 19, fig. 34. 



Fucus Seaforthii Turner, Fuci, pi. 190. 



Thamnophora ? Seaforthii Ag., Spec. 



Alg., p. 227. System., p. 240. Mon- 

 tagne in Ramon de la Sagra, Hist. 

 Cuba, Bot., p. 56, pi. V, fig. 1. 



Alsidium Seaforthii J. Ag. in 

 Linnsea, vol. 15, 1841, p. 28. 



Cfr. DE-TONI, Sylloge Algarum, 

 vol. IV, p. 975, where more synonyms 

 are named. 



The specimens found are 

 all distichous. I have not seen 

 any specimen like forma imbri- 

 cata J. Ag. 



Regarding the development 

 of the thallus FALKENBERG de- 

 scribes it as follows: "Haupt- 

 und Seitensprosse produciren, so 

 viel ich gesehen habe, nur un- 

 mittelbar vor ihrem Erloschen 

 schraubig gestellte Blatter ohne 

 Achselsprosse; die Seitensprosse 

 ihrerseits scheinen stets ohne 

 vorhergehendes Tragblatt zu 

 entstehen, so dass bei den zwei- 



Fig. 284. Bryothamnion Seaforthii 

 (Turn.) Kiitz. 16, successive gene- 

 rations of branches and trichoblasts; 

 at 1 the first segment of the main 

 stem just begins to grow out; 2, shows 

 a young trichoblast; 3 and 4, tricho- 

 blasts with axillary branches; at the 

 base of branch 5 the scar of the 

 trichoblast is seen. (About 300 : 1). 



