256 University of California PuUimtions in Botany [Vol. 8 



J. Agardh, Till Alg. Syst., part 3, 1883, p. 126 ; Collins, Green Alg. 

 N. A., 1909, p. 203. Conferva flexuom Wulf., in Roth, Cat. Bot., II, 

 1800, p. 188. 



J. G. Agardh {loc. cit.) is responsible for separating this species 

 from among the forms previously referred to E. intestinalis. No 

 recent examination of the type is reported. As taken by J. G. Agardli 

 it seems to be a simple, more or less slender tube with the cells 

 arranged in longitudinal rows and with the membrane somewhat 

 thickened on the inside. It is generally regarded as being an inhab- 

 itant of warmer waters (cf. J. G. Agardh, 1883, p. 127, and Collins, 

 1909, p. 203). We have not seen it on our coast, but J. G. Agardh 

 credits to this species a specimen collected by Mrs. Bingham at Santa 

 Barbara, California. 



9. Enteromorpha tubulosa Kuetz. 



Plate 14, fig-s. 4, 5 



Frond simple or with short proliferations, usually near the base, 

 but with occasional longer proliferations some distance above the 

 base, tubular and nearly cylindrical throughout, or enlarging upward 

 from a delicate cylindrical stipe and becoming compressed above; 

 cells squarish, 11-15/a diam., arranged in longitudinal series through- 

 out, less distinctly so in the upper mature parts; membrane 15-24/a 

 diam., walls equally thickened on both sides, with cells squarish or 

 slightly elongated radially, chromatophore filling the outer end of 

 the cell. 



Growing attached to rocks in the lower littoral belt, or floating in 

 intertwined masses in pools in salt marshes. Central California. 



Kuetzing, Tab. Phyc, 1856, p. 11, pi. 32, f. 2; Ahlner, Entero- 

 morpha, 1877, p. 49, f. 9a, 9b. Enteromorpha pralifera var. tuhidosa 

 Collins, Green Alg. N. A., 1909, p. 203 ; Collins, Holden and Setchell, 

 Phyc. Bor.-Amer. (Exsicc), no. 462 (Key West, Florida). 



Kuetzing 's figure of Enteromorpha tuhidosa represents a simple 

 plant, but J. G. Agardh (1883, p. 128) states that it branches. The 

 main frond is tubular and slender, of nearly uniform diameter 

 throughout. Our specimens are all branched more or less, but usually 

 from near the base. The membrane may be thickened on both sides 

 or not at all. There has been some difference of opinion among writers 

 as to the proper relationship of this plant, but it seems best to us to 

 retain it as an independent species. 



