FRESH-WATER ALGiE OF THE UNITED STATES. 207 



Genus DEAPARNALDIA, Ag. 



Fila articulata ramosa, e cellulis magnis, maxime hyalinis, fascia chlorophyllosa latiuscula ornatis, 

 semper sterilibus formata, fasciculis penicillato-ramuloslssimis, e cellulis minoribus fevtilibus eom- 

 positis, plus minus dense obsessa. Articuli temiinales omnium ramulorum inanes acbroi steriles, in 

 pilum hyalinura plus minus elongati. 



Filaments articulated, branched, formed of large cells which are chiefly li^yaline, but furnished with 

 a transverse chlorophyllous fascia, more or less densely clothed with penicillately ramulose fasciculi, 

 formed of smaller fertile cells. Terminal articles of all the joints empty, trausparent, sterile, and 

 elongate, in a more or less hyaline hair. 



D. glomerata, (Vauoh.) Ag. 



D. filis ramisque priraariis achrois vel subachrois, ad 0.0014'?" crassis, articulis inferioribus 

 diametro aequalibus vel paulo brevioribus, geniculis manifesto constrictis, fasciis chlorophyl- 

 losis angustis dilute viridibus ; ramis primariis subrectangulo-patentibus, saepe oppositis ; 

 ramulorum fasciculis confertis, patentibus, alternantibus vel oppositis, dense ramellosis, sub- 

 ovalibus, obtusis. (R.) 



Syn. — D. glomerata, (Vaucher) Agardh. Rabenhorst, Flora Europ. Algarum, Sect. lU. 

 p. 38. 



fla&.— Rhode Island ; (S. T. Olney) Thwaites. 



Filament and primary branches colorless or subcolorless, and reaching 0.00141" in diameter, 

 lower articles about as long or a little shorter than broad, manifestly constricted at the 

 joints, chlorophyl fascia narrow, light green ; primary branches subrectangularly patent, 

 often opposite ; fasciculi of brtijiches crowded, patent, alternating, or opposite, densely 

 ramellose, suboval, obtuse. 



EemarJcs. — According to M. Thwaites the true Dr. glomerata grows in Rhode 

 Island, as he so identified specimens sent to him by Mr. Olney. These specimens 

 were, however, in all probability dried, and if this was so, I confess not to attach- 

 ing much weight to the identification. The Draparnaldia, common near Philadelphia, 

 is at once so like and yet so different from the description of D. glomerata, that I 

 am unable to fully satisfy myself whether it be a variety of the European species 

 or distinct from it. It differs very greatly in the thickness of the stem and pri- 

 mary branches. I have given above Prof. Rabenhorst's description of the Euro- 

 pean variety, and now append one of th'. plant growing in this neighborhood. 



Var. maxima. 



Dr. filis achrois, ad 004" crassis, articulis plerumque diametro duplo longioribus, in medio 

 ssepe valde tumidis; ramis primariis achrois vel subachrois, oppositis vel alternantibus vel 

 ternatis, elongatis, dense ramellQsis, cum raniulis lanceolatis ; ramulorum extremorum 

 fasciculis dense ramelosis, ovatis vel Iftte lanceolatis, plerumque confertis; ramulorum 

 articulis inferioribus plerumque diametro (ad ^^V..") 5ib*qualibus, articulis superioribus 

 diametro duplo aut triplo longioribus, plerumque piliferis. 



^o6.— Props Philadelphia ; Wood. 



Filament transparent, attaining a diameter of 0.004", its articles mostly twice as long as 

 broad, strongly swollen in the middle ; primary branches colorless or subcolorless, opposite, 

 alternate or ternate, elongate, densely ramellose with the rarauli lanceolate ; fasciculi of 

 extreme branches densely ramellose, ovate, or broadly lanceolate, mostly crowded, inferior 

 articles of the branches mostly about as long as broad (,^\,"), superior articles two to three 

 times as long, mostly piliferous. 



