136 FRESH-WATER ALGJS OF THE UNITED STATES. 



outline in which all the sinuses are of similar form, and the central and basal lobes 

 are about equal size; whereas, when viewed from the front, the basal lobe is much 

 the broader. When the desmid is viewed from the side it is seen to be enlarged 

 in the centre, and provided with two distinct umbonations each side of the com- 

 paratively narrow central sinus. 



Fig. 10, pi. 12, represents the front view of a frond of this plant; fig. 5, pi. 20, 

 the outline of a two-thirds view, and fig. 5 a, the outline of a lateral view, all mag- 

 nified 450 diameters. 



E. Yerrucosuni, EHRB. 



E. magnum, late ovatura, vix longius quam latum, medio profunde constrictum, sinu extrorsum 

 dilatato; semicellulis trilobatis, lobis triangularibus, divergcntibus, apice late et profunde 

 sinuatis ; a latere ovato-oblongum, sinuato-lobatura, lobis octo in apice rotundatis, polaribus 

 singulis porrectis, lateralibus terms ; cytiodermate granulato-verrucoso. (R.) Species mihi 

 ignota. 



Long. 0.0036" 0039". (R.) 



Syn. E. verrucosum, EHRENBERQ. RABENHORST, Flora Europ. Algarum, Sect. III. p. 179. 



Hob. South Carolina ; Georgia ; Florida ; Rhode Island ; Bailey. 



Frond somewhat longer than broad, rough all over with conic granules ; segments 3-Iobed, 

 sqme what .divergent, all the lobes broad, cuneate, with a, very broad, shallow, or external 

 sinus. Empty frond ; f. v. segments with one large circular basal inflation on surface, one 

 smaller on each side, and two others on the end lobe ; s. v. segments inflated at the base, 

 narrowed into a short neck, end dilated with a central sinus ; e. v. oblong, with three infla- 

 tions at each side, one at each end, end lobe having 4 divergent lobelets. (A.) 



E. geiumatiim, BREB. 



E. mediocre, diametro duplo longius, profunde constrictum, sinu angusto linear!, a vertice ovato- 

 oblongum, arabitu sinuato-lobatum, lobis 8 couformibus, rotundatis ; semicellulis trilobatis, 

 basi tumoribus 3 in seriem dispositis, lobis in apice profunde emarginatis, lobnlis rotundatis, 

 lobo polari dilatato et paulum producto ; cytiodermate in tumoribus et lobulis granulato- 

 punctato, cseterum Isevi. (R.) Species mihi ignota. 



Long. 0.00224" 0.0029". Lat. 0.00157'' 0.0011". (R.) 



Syn. E. gemmatum, BREBISSON. RABENHORST, Flora Europ. Algar., Sect. III. p. 180. 



Hab. Rhode Island ; Bailey. 



Frond scarcely twice as long as broad; segments 3-lobed, lateral lobes horizontal, deeply emar- 

 ginate, the pro.tuberances minutely granulate; end lobe dilated, its dilatations inclined 

 upwards, and minutely granulate ; ends with a deep rounded emargination. Empty frond 

 slightly punctate ; f. v. segments with three granulate inflations near the base ; tr. v. broadly 

 elliptic, with three granulate inflations at each side and one at each end ; e. v. end lobe cruci- 

 form, lobelets rounded, granulate. (A.) 



E. ohloii iim, (GREV.) RALFS. 



E. magnum, diametro duplo triplove longius, oblongum, profunde constrictum, sinu angusto, 

 a latere oblongo-lanceolatum, utroque polo truncato- leniter retusum, ambitu undulato- 

 sinuatum ; semicellulis (fronte) sinuato-quinquelobis, basi et in quoque lobo tumore instructis, 

 lobis lateralibus in apice dilatato sinuato-retusis, inferioribus latioribus quam superior., lobo 

 polari late cuneato in apice profunde inciso, angulis omnibus rotundatis, cytiodermate Isevi ; 

 zygosporis globosis verrucosis, verrncis obtuse conicis achrois hyalinis. (R.) Species mihi 

 ignota. 



