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



solitariiim, Acrochaetiimi affine, Phaeostroma piisillum, Microchaete 

 nana, etc. 



The exterior parts of this interesting Httle endo-epiphyte form 

 subhemispheric or oblong cushions 125-300 /x in diameter. The 

 cushions include numerous plurilocular sporangia but we have 

 seen only two or three unilocular sporangia, while in the European 

 plant, so far as we are acquainted with it, the unilocular sporangia 

 seem to be much more frequent.^ The North Carolina plant 

 seems to differ furthermore from the European in the smaller 

 cushions, in the smaller diameter of its shorter filaments, and in 

 having the sterile filaments, except their hairs, of about the same 

 length as the plurilocular sporangia instead of conspicuously 

 overtopping them. However, our plant has so many points in 

 common with the European endo-epiphyte on the same host that 

 we do not feel justified at present in considering it anything other 

 than a small form of that species. A section of the cushion does 

 not show the large colorless cells described and figured by Harvey 

 as belonging to its basal part, but we do not find such in European 

 specimens that we have examined; the exterior filaments spring 

 from a small endophytic cushion made up of cells that are scarcely 

 or not at all larger than those of the filaments, much as figured for 

 this species by Sauvageau. 



In the North Carolina plant, the vegetative filaments of the 

 cushion are mostly 50-85 ^ long and 7-9 m in diameter; many of 

 the shorter terminate in a hair 10-12 ix in diameter and often 

 reaching a length of 400 ix. The plurilocular sporangia are fusi- 

 form or filiform, mostly 30-50 ^u long and 5.5-8.0 /i in diameter; 

 many of them consist of a single series of loculi, but more of them 

 are two loculi broad except at base and apex, and rarely one may 

 show three loculi across the middle. The endophytic filaments 

 are of about the size of the epiphytic or a little stouter; they seem 



^According to Batters, loc. cit., the "paranemata with short articulations," de- 

 scribed and figured by Harvey, are the plurilocular sporangia, as are also, in part at 

 least, the filaments figured by Areschoug. It seems to us probable that the plant 

 figured by Kutzing (Tab. Phyc. 8: i. pi. i. f. i. 1858) under the name Phycophila 

 stellulata is not Elachistea stellnlata (Harv.) Griff. The host, as figured by him, does not 

 look like Dictyota dichotoma, the sterile filaments differ from those of E. stellulata in 

 being conspicuously inflated near the middle, and the plurilocular sporangia are appar- 

 ently more elongate and filiform. We find plurilocular sporangia abundant in speci- 

 mens from Clare Island, Ireland, collected by A. D. Cotton, while in Crouan, Alg. Mar. 

 Finistere / and Desmaziere, PI. Crypt. Fr. 18 18, we have noted only unilocular sporangia. 



