184 Rhodora [Auausr 
them. "Тһе host was more or less infested, almost to the extreme ends 
of the young branchlets. 'l'he germinating spore appears generally 
to send out the horizontal filaments at once, but no erect filaments; 
these arise later from the horizontal layer. When the end of one 
horizontal filament encounters another filament, it may either attach 
itself and cease growing, or bend until it is parallel to the other fila- 
ment, adhering to it laterally. Short erect filaments are abundant, 
seldom over 25 y long, normally ending in a pyriform spore; much 
less common are the long filaments, straight, long-jointed, usually 
simple and sterile, occasionally with one or two lateral spores, usually 
sessile, rarely borne on a short cell. 
Several other epiphytes were growing on the Desmarestia; Stre- 
blonema oligosporum Stromf., Acrochetium Daviesti (Dillw.) Nàg., 
Erythrotrichia ceramicola (Lyng.) Aresch., a young Polysiphonia 
and some small, sterile, Peysonnellia-like disks. Desmarestia viridis 
is an abundant plant all along the New England coast, and hardly 
any abundant species is so generally free from epiphytes; it would be 
interesting to know what combination of circumstances at this place 
made it an attractive residence for all these species. А 
A. Hoytii n. sp. Cellula basali (spora originali) rotundata, 12-25 p 
diam., vel verticaliter elongata, tunc ad 30 и longa, filamenta 1-3 
erecta, 6-7 y diam., emittente, cellulis 2-4 diam. longis; ramificatione 
subfrequente inferne, superne minus frequente, ramis ultimis præ- 
longis, simplicibus vel subsimplicibus, in setam tenuissimam attenua- 
tis. Sporis lateralibus, oblongis, 6-15 џ, ad pedicellum unicellulare, 
parte superiore filamenti affixis. 
Basal cell (original spore) 12-25 м diam., spherical or somewhat 
elongate vertically, then up to 30 y long; 1-3 filaments arising. from 
each basal cell; main filament about 6 и diam., cells 2-4 diam. long; 
branching rather frequent below, rarer above; ultimate branches 
very long, simple or nearly so, gradually tapering into a hair. Spores 
lateral on the upper part of the filament and branches, on one-celled 
pedicels, oblong, 6 X 15 u. On Dictyota dichotoma (Huds.) Lamour., 
Beaufort, North Carolina. W. D. Hoyt. 
In. this species the germinating spore not merely remains distinct 
through the life of the plant, but increases to several times its original 
size, and may send up more than one vertical filament. At least this 
seems to be the only explanation of the appearance presented. The 
large cell is more or less imbedded in the cortex of the host, but has 
neither descending nor lateral growth. Among American species it 
seems nearest related to A. Dasyæ Collins, but in the latter the per- 
