THE MARINE ALG^ OF NEW ENGLAND. 59 



.35-60 mm , sporiferous. mass .04-S mm broad by .10-15 mm long. Spores 

 .015 u,m by 020 mm . 



On wharves and rocks between tide-marks, mixed with Calothrix scop- 

 ulorum and Ulothrix. 



Eastport, Me.; Gloucester, Mass. ; Europe. 



Probably common in the autumn along our northern coast, and at once recognized 

 by the long terminal stalk, which appears to be an appendage of the cell- wall. The 

 size is so variable that no accurate measurements as to length can be given. Those 

 above stated represent the size of fully-grown sporiferous individuals. 



Suborder BRYOPSIDE^E. 



Fronds green, unicellar, filamentous, branching; reproduction by 



zoospores, with two cilia, formed in the occluded branches. 



A small suborder, including with us a single species of Bryopsis and a single species 

 of Derbesia, a genus whose position is uncertain and which may prove to be more 

 nearly related to Vaucheria than to Bryopsis, although in the present article we have 

 placed it with the latter. 



BEYOPSIS, Lam. 



(From (Spvov, a moss, and oipi?, an appearance. ) 



Fronds bright-green, unicellular, branching, usually pinnately di- 

 vided; reproduction by spores formed in occluded portions of the 

 branches ; spores of two (?) kinds — either green zoospores, furnished 

 with two apical cilia, or orange-colored. 



The genus Bryopsis includes perhaps not far from twenty species, which are charac- 

 terized by the. mode of branching. Most of them are pinnately compound, and the 

 different forms pass so gradually into one another that the species cannot be said to 

 be well marked. The fronds are unicellular except at the period of reproduction, 

 when some of the smaller branches are separated by partitions from the rest of the 

 frond. The position of the genus is still doubtful, as the development is not known. 

 The reproductive bodies generally found are green zoospores which have two termi- 

 nal cilia. Whether they conjugate or not is not known, although as Thuret reports 

 the occurrence of zoospores with four cilia, such is probably the case. A second form 

 of reproductive bodies was found by Piingsheim in Bryopsis, orange-colored motile bod- 

 ies furnished with two terminal cilia. The development of these bodies has not been 

 observed. Janczewski and Rostalinski have expressed the opinion that they may be 

 parasites, but Comu confirms the statement of Pringsheim that they are really organs 

 of the Bryopsis. 



B. pltjmosa, (Huds.) Ag., Phyc. Brit., PI. 3. PI. IV, Fig. 1. 



Fronds 2-6 inches long, often gregarious, 2-4 times pinnate, pinnule^ 

 pyramidal in outline, naked at the base, in the upper part clothed with 

 short pinnule, which are constricted at base. 



On muddy wharves and stones at low- water mark. 



A beautiful species, not uncommon along our whole eastern coast, and also frequently 



