HOWE AND HOYT: MARINE ALGAE FROM BEAUFORT, N. C. II5 



nent. Specimens, however, that have been mounted in glycerine 

 or glycerine- jelly may be washed off with water and restained 

 with iodine at any time. 



Erythrocladia vagabunda sp. nov. 



Endophytic or pseudo-epiphytic, creeping in the superficial cell 

 walls of other algae; thallus consisting chiefly of irregularly 

 branching, uniaxially elongate or irregularly radiating filaments, 

 finally spreading over areas 0.75-2.25 mm. long or broad, often 

 anastomosing .or pseudo-anastomosing, and commonly forming 

 here and there small irregular pseudoparenchymatous patches 

 mostly 2-6 cells broad; ramification mostly lateral, rarely subdi- 

 chotomous, often divaricate or rectangular; cells (protoplasts) 

 for the most part irregularly oblong in surface view, often curved 

 or I- or 2-lobed, 9-40 /x long, 6.5-15 /x broad; pyrenoids 1-4 (usually 

 I or 2), 2-3/1 broad; monoecious (?); sporocarps forming single 

 carpospores (rarely 2?), these ovoid, oblong, or irregular, mostly 

 12-25 M in maximum diameter; non-sexual spores unknown. 

 [Plate 12, figures 6-1 i; plate 13, figure 2.] 



In the superficial cell walls of Dictyota dichotoma, dredged "in 

 133^-14 fathoms," Lewis Radcliffe, August 11, 1914; associated 

 with Acrochaetium affi?ie, Microchaete nana, Elachistea stellulata, 

 Streblonema solitarium, Erythrocladia recondita, etc. 



Erythrocladia vagabunda is evidently a close ally of E. recondita, 

 but appears to differ in its straggling, obviously filamentous 

 habit, in its more rectangular branching, in its forming pseudo- 

 parenchyma, if at all, in small irregular scattered patches instead 

 of in a single central area, and in having cells of nearly twice the 

 average diameter of those of E. recondita. It was our first im- 

 pression that it might be considered a variety of E. recondita, 

 connected perhaps with its deep water habitat, but we finally 

 observed that it was associated, without intergrading, with a 

 more minute, smaller-celled endophyte, the free filaments of which 

 radiate from a pseudoparenchymatous center. This smaller plant 

 we take to be the true E. recondita, very slightly modified by its 

 deeper habitat. When iodine is applied, the protoplasts of this 

 smaller plant take a darker blue-black or violet-black color than 

 do those of the larger E. vagabunda. The two plants are shown 

 side by side and more or less intertangled in our photograph. 



With the more limited material at our disposal, we have not 

 been able to demonstrate the sexuality of E. vagabunda so satis- 



