Holmes puts this plant in the same section as Codium galea* 

 turn and C. mamillosum. This is without doubt an error due to 

 the incomplete specimens sent to him. It belongs to the section 

 C. dongatii J. Ag. In the fresh state the present plant is easily 

 discernible from the related plants by its colour, its brittle sub- 

 stance and by its sufficiently large utriculi so as to give a granular 

 appearance to the frond, each being perceptible even in naked 

 eyes. In the herbarium specimens the deep-colored median lon- 

 gitudinal zone is fringed by pale-green borders. The translucence 

 of this border is clue to the existence of long and thick utricles. 



In pearl-oyster beds this plant often causes a fearful damage 

 suffc citing oysters by piling up on it. 



PL. CXLI. Fig. 1 : terminal portion of a frond of Codium 

 cylindricum Holm., \. Fig. 2 : diagramatic illustration of an entire 

 frond, with a basal portion, a. Fig. 3 : surface view of the upper 

 branch showing large utriculi in nat. size. Fig. 4 : three young 

 fronds, \. Fig. 5-6: younger utriculi, -y ; 736,X272 //, 700x345 

 /'. resp. Fig. 7 : utricu'us bearing gametangia, 909 a thick, 4^. 

 Fig. 8 : utriculus bearig gametangia and scars of colorless-hairs, 

 (2 mm. long, 290 ," thick), -. Fig. 9-11 : different forms ot 

 gametangia, -. 



Codium cylindricum Holm. 



fg CXLI H JR. 

 - V 7, I-I5 m. a Jg 5/, f T^ ' ift * * 



