FRESH-WATER ALGuE OP THE UNITED STATES. 139 



linear. Empty frond minutely punctate ; f. t. narrow elliptic, with several inflated protube- 

 rances, ends scarcely dilated, rounded ; tr. v. with four inflations at sides and one at each 

 end. (A.) 



circniare, Hassal. 



E. mediocre, diametro duplo longius ; semicellulis trilobis (at non semper distincte), ad basin 

 versus tumoribus quinis aut pluribus in series duas v. tres alternantes aut singulo centrali, 

 quaternis semicirculariter ordinatis instructis, lobis basalibus sinuato-emarginatis, subito in 

 lobum polarem apice paullum dilatatum attenuatis ; cytiodermate subtiliter punctate. (R.) 



Syn. — E. circulare, Hassal, Fresh-Water Algse, p. 383. 



Hah. — Providence, Rhode Island ; Bailey. 



"Frond about twice as long as broad, tapering upwards into a neck, end not dilated, its notch 

 an acute incision. Empty frond, segments with five basal inflations, four in a half circle 

 around the fifth and two others at the extremity." Archer. 



{Var. Kalfsii) 



Semicellula tumoribus minimis 11 in series tres alternantes ordinatis. 



Hah. — Saco Lake, New Hampshire ; (F. W. Lewis) Wood. 



E. Jenneri, nobis. Frond scarcely twice as long as broad ; segments 3-lobed, basal portions 

 subquadrate, emarginate at the sides ; end lobe, its notch linear. Empty frond punctate, 

 segments with several inflations arranged in alternate lines. (Archer.) 



E. insigne, Hassall. 



B. subgracile, diametro duplo-triplove longius, a vertice fere quadratum, lateribus concavis, 

 angulis rotundatis ; semicellulis basi inflatis, integris, e basi subreniforrai in collum elongatnm 

 citius attenuatis, lobo polari dilatato bifido truncato ; cytiodermate subtiliter punctate. (R.) 



Long. 0.0039"— 0.0043". Lat. max. 0.00236". (R.) 



' Syn. — E. insigne, Hassall, Fresh- Water Algae, p. 21. 



Hah. — Florida ; Rhode Island ; Bailey. 



Frond rather more than twice as long as broad ; segments inflated at base, sides entire, without 

 lateral tubercles, and tapering into a long slender neck ; end lobe dilated, its notch linear. 

 Empty frond minutely punctate ; f v. segments with two inflations at the base ; f. v. narrower, 

 gradually tapering to the end, which is considerably dilated ; projections rounded, with a 

 sinus between ; tr. v. subquadrate, slightly concave at sides, with a rounded lobe at the 

 centre of each end ; e. v. end lobe with a sinus at opposite external margins, angles thus 

 protruded into four divergent rounded lobelets. (A ) 



E. Ralfsii, Rabenh. 



E. mediocre, leviter compressum, medio inflatum, diametro duplo circiter longius ; semicellulis 

 pyramidalibus, e basi ventriuosa in lobum polarem rectum truncatum sinuato-attenuatis ; 

 cytiodermate subtiliter punctato, punctis in lineas rectas ordinatis. (R.) 



Syn. — E. ansatum, Ehr. etauctores. Rabenhorst, Flora Europ. Algarum, Sect. III. p. 184. 

 E. Balfsii, Rabenhorst, Flora Europ. Algarum, Sect III. p. 184. 



Hob. — South Carolina ; Rhode Island ; Bailey. White Mountains, New Hampshire (F. W 

 Lewis). 



"E. ansatum, Ehrh. Frond about twice as long as broad ; segments inflated at the base, taper- 

 ing upwards without sinuations into a neck, end not dilated, rounded, its notch linear. Empty 



