108 DESMIDS OF THE UNITED STATES. 



E. CUNEATUM, Jenner. Plate XXIX, figs. 12, 13. 



Semi-cells cuneate, not lobed ; terminal notch linear. 

 Diameter of cell 24-28 //. ; length about 75 /*. 



Not rare ; seems of rather doubtful value as a species. 



E. MAGNIFICUM, Wolle. Plate XXIX, figs. 6-8. 



The largest of our Euastra; about twice as long as broad ; 

 semi-cell five lobed, the terminal lobe exserted ; dilated, end 

 somewhat convex, connected by a short neck ; basal and 

 intermediate lobes entire, with a deep obtuse notch between ; 

 upper margin of the basal lobes nearly horizontal and par- 

 allel with the base of the semi-cell ; no prominent tumors, 

 but one large central undulate inflation shown in lateral 

 view (fig. 7). End view (fig. 8) shows the terminal and in- 

 termediate lobes notched at each side. 



Diameter 100 /J. ; length about 190 yu. 



Ponds, near Malaga and Manchester, New Jersey. 



Var. CRASSIOIDES, Hastings. 



A form which may be described as intermediate between 

 E. magnificum and E. crassum. In end view and size it is 

 nearly like the first, but the intermediate lobe is, in this view, 

 rounded, not "notched." In lateral view this lobe is notched 

 and the central inflation is seen to be most prominent near 

 the base of the semi-cell. In front view it has the outlines 

 of E. crassum. 



Collected near Rochester, N. H. 



E. WOLLEI, Lagh. Plate XXXIII, figs. 1-5. 



G. von Lagerheim, of Stockholm, Sweden, has seen fit to 

 change the name of our E. intermedium, Cleve, for the reason 

 that he finds that it does not correspond with the Swedish 

 plant so named by Cleve. It has much of the form, but is 

 much larger, having more than twice the diameter and twice 

 the length. Cleve states the diameter of the plant described 

 by him at 44 //. ; and length 77-80 yw. Diameter of our form 

 is 112-120 yw. ; length 160-170 ju. ; moreover the end of the 

 semi-cell of the Swedish plant is <wo-lobed, ours is four- lobed. 

 An apology for the error in choosing the name is unneces- 

 sary. Will only remark, a full description of Cleve's plant 

 was not convenient at the proper time. 



Var. QUADRIGIBBERUM, Lagh. Plate XLIX, fig. 29. 



Semi-cells with four horizontal inflations ; in vertical view 

 elliptic, apices acuminate, sides quadriundulate. 

 Tewksbury, Massachusetts. 



