Frond cylindrical, a little expanded only beneath forks, rlabel- 

 lately dichotomous, often trichotomous here and there, more or less 

 swollen toward apical segments into subclavate shape, 10-17 cm. 

 high, 3-5 mm. in diameter. Utriculi cylindrico-clavate, 140-165 , 

 broad at the apex, 5-7 times as long as broad, not much thickened 

 and obtuse or subtruncated at apex. Sporangia ovato-fusiform, 

 90-290," long, 53-73 A' broad, situated above the half way. Colour 

 deep green. Substance thick and tough. 



Hab. : On rocks between tide-marks (Boshyu). Ryukyu, 

 Futae (Amakusa Isl.), C. Shiwo (Prov. Kii), Enoshima and Boshyu ; 

 Prov. Tsushima, Prov. Idzumo, Prov. Tajima. Fruit: May August, 

 Geogr. distr. : Feuerland, Provenir (Svedelius). 



Remarks: Among our species of Codium the present plant 

 much resembles Codium mucronatwn var. californicum in its 

 cylindrical habit and is often mistaken for it. The present plant is 

 found in the warmer part of the country, while the species just 

 spoken of has more wider range of distribution within our country. 



PL. CXX, Fig. 1-8. Fig. 1 : frond of Codium contractum 

 Kjellm. in nat. size. Fig. 2: utriculus with thickened apex, 163^ 

 broad at top, ?. Fig. 3: thin-walled utriculus, 140/7 broad, 2*. 

 Fig. 4 : apex of an utriculus showing the thickness of apical wall, 

 ^-. Fig. 5 : one bearing two gamentangia, ^*. Fig. 6 : two of 

 gametangia, 290/^x54,0 and 9i,*73, resp., **-. Fig. 7: gamet- 

 angium, ^. Fig. 8 : portion of the same magd., 5 ^. 





