400 University of California Publications in Botany [Vol.6 



ment of the cystocarp. As a result, I am now able to give the follow- 

 ing account of the genus. 



Farlow remarked that his Nemalion Andersonii differs from other 

 species of Nemalion in being dioecious, as he had only the antheridial 

 plants or sterile ones from which to judge. I soon discovered that 

 Cuniagloia Andersonii is a dioecious plant ; at least, all of the speci- 

 mens thus far examined have been either antheridial or cystocarpic. 

 Plants may be found in the future which are, however, monoecious. 

 I make this reservation because I have found that Nemalion luhricum 

 which grows along the California coast and to which Cumagloia An- 

 dersonii is closely related, is not constant in this respect, but is 

 mostly dioecious, with an occasional well-developed normal monoecious 

 plant. In an aggregation of matured plants consisting of both sexes, 

 it is usually easy to segregate the sexes on morphological characters 

 alone, the antheridial plants as a rule being larger, with longer 

 branchlets, less profuse!}- branched, and lighter in color. 



Plants range in size from a few inches up to over two feet in 

 length. Those which have come to us from the northern regions are 

 the smallest. Those on the California coast average about six inches 

 long. The diameter of the main fronds is about 2-3 mm. The hold- 

 fast is solid and disk-shaped. Frequently several fronds arise from 

 the same holdfast (pi. 31, figs. 3-4), and possibly this may persist 

 for more than one fruiting season. At least I have noticed small 

 young fronds just arising by the side of mature plants on the same 

 holdfast. The fronds are usually solid, but occasional!}' plants grow- 

 ing higli up on rock ledges wliere tliey are exposed to tlie air a con- 

 siderable portion of t!ie time maj^ become saccate (pi. 31, fig. 4). 



Tlie fronds are composed of a few slender, sparingly branched 

 filaments with gelatinous walls extending lengthwise through the 

 center, and connected here and there to other similar filaments extend- 

 ing lengthwise of the frond in a circle around the center. These latter 

 filaments in particular are composed of alternating long cells and 

 verj^ irregularly shaped short, joint-like cells. These joint-like cells 

 give rise to the cells which connect with neighboring filaments and 

 particularly to the filaments which compose the cortex. The cortical 

 filaments remain unbranched for two or three cells usually, then 

 branch dichotomously or rarely trichotomously for three or four divi- 

 sions, ending in more or less pear-shaped cells which form the compact 

 surface layer. When the antheridia are to be developed, one and 

 sometimes both of the dichotomies of the division next to the last 



