— 75 一 



than the remaining ones, though they are not so long as in the Atlantic 

 plant. But consiclerino- that even amonp- the Atlantic forms there are 

 various deviations from the typical plant in the length of ramuli (3-20 

 mm.) and number of articulatioas, yet they are put in the same species 

 (e.g. Gastr. sitbartictdatum Kuetz., uastr. wnbcllatum Kuetz.) we may 

 take our plant as one and the same species as the European. If it 

 -should prove in other days to be not the same species, it would be a 

 variety, but never a distinct species. 



Hab. : On rocks between tide-marks or still lower. Prov. Bo- 

 shyu, Choshi and Obama (Prov. Kadzusa), Prov. Hitachi, Onahama 

 (Prov. Iwaki). Tetraspores and cystocarps : ― late spring to summer. 



PL. XVII, rio-s. i-io. Fig'. 1: リ astroclonium ovale in nat. state 

 and size. — Fig. 2 : portion of the cross-section of stem, '\ -. — Fig. 3 : 

 longitudinal section of a ramulus bearing tetrasporanp'ia cut through a 

 dissepiment, ― Fig. 4 : portion of the longitudinal section of a 

 ramulus showing- the connection of the wall of frond with a dissepiment, 

 2^0. 一 Pi rr. 5: surface-view of a dissepiment, -^. — rig. 6: ramulus 

 bearing tetrasporanp^ia, や. 一 r*i ゾ， 7 ： one of ramuli bearing tetra- 

 sporangia, magnified, — Fi ゾ. 8: tetrasporangium,^^^. — Figs. 9-10. 

 tetrasporangia divided into more than four, "0. 



Gastroclonium Kuetzing 1843. 

 ' • - ' いそまつ 屬. 



RHODYMENIACEAE. だ る す 科. 

 體ハ圓 柱狀ュ シテ 分岐 シ, 中 S ，所々 - 多角形 ノ 細胞 ヨリ 成 



レ ノレ 橫 隔膜 ヲ以テ 區劃セ ラ レ*» 下 部 時 トシ テハ中 實-シ テ莖/ 

 如 キ觀ヲ 呈ス. 枝メ 、中空 ュシタ 所々 溢レ， 其 溢レタ ノレ 所- 隔 



