SPHAKR070SMA. 29 



S. i-i Lciuu'-M. Hailcy. Plate IV. figs. 1, 2. 



Cells twice as broad as long, deeply incised on each side, 

 ends rounded, junction margin straight, filaments twisted, 

 frequently enclosed in a gelatinous envelope. 



Diameter 60-82 /*. 



Var. PLANUM, Wolle. Plate IV. figs. 3, 4. 



Similar to typical form, except in size and in the absence 

 of the twist in the filaments. 

 Diameter 30-38 ji. 



Var. INFLATUM, Wolle. Plate LX, fig. 8. 



Differs from the preceding in the central inflation, pro- 

 ducing a short isthmus between the cells. 

 Diameter 38 p. 



The typical form appears to be widely scattered throughout 

 many States : Rhode Island, Massachusetts, Pennsylvania, 

 New Jersey, South Carolina and Florida. The variety plamnn 

 I found in a trench aside the railroad near Metucheu, N. J. 

 The water was green with the abundance of it. The variety 

 influtum occurs sparsely in ponds of New Jersey. 



S. FILIFOBME, Rab. Plate IV, figs. 5, 6. 



Cells about as long as wide, constricted in the middle with 

 a deep, acute incision ; ends of lobes rounded, connected by 

 two sessile glands. 



Diameter 12-18 /*. 



Pond waters of Pennsylvania and New Jersey. 



General appearance very near S. jtufchntm variety, but 

 smaller, and length of cell equal to the diameter. Did not 

 observe a gelatinous sheath mentioned by Rabenhorst ; Kirch- 

 ner admits no sheath. Fig. 6 is very near Corda's S. lamelli- 

 ferion. 



S. PULCHELLUM (Arch.) Rab. Plate XII, figs. 8, 9. 



Cells in outline oblong with the middle much inflated, 

 sharply incised and angles rounded ; ends narrower because 

 not at all or very slightly inflated ; apices square ; varying 

 in length from one to nearly two diameters. 



Diameter 9-10 //. 



Pond waters, not rare. Syn. Sf>ondylosium bambusioides, 

 Witt. S. pulchellum, Arch. 



