40 FRESH- WATER ALGvE OF THE UNITED STATES. 



M. ALATA, Wall. Plate LXII, fig. 1. 



In anticipation of the possible discovery of this inter- 

 esting and unique form in Southern Florida, I quote it from 

 G. von Lagerheim's Bidrag till Amerikas Desmidie-flora. It 

 is an India plant, but is now also found in Cuba. The figure 

 is drawn direct from an India specimen in my herbarium. 



M. FURCATA. V. Des. U. S. p. Ill, var. SIMPLEX, Wolle. 



Plate LIX, figs. 6, 7. 



Cell equal in length and breadth, two-lobed, terminal lobe 

 exserted, its divisions spreading and producing a wide, shal- 

 low sinus ; lateral lobes usually simple, but sometimes 

 divided into two narrow, linear diverging sections, furcate 

 at apices. Length and breadth 140-150 yw. 



A singularly variable species. Of thirty-one fresh speci- 

 mens examined during a stay at Winter Park, Florida, by 

 Rev. H. D. Kitchel and myself, twenty were found of nor- 

 mal form as upper half of fig. 6, 7, no arms divided ; five 

 had all the lateral arms divided, like the lower half of figure ; 

 one had two arms divided and two single, like figure ; two 

 had only one arm divided, and three had each two arms 

 divided. As two-thirds of the forms examined had all the 

 arms single, this is considered the type ; the others, one- 

 third, variable, are varieties. 



M. CRUX MELITENSIS. V. Des. U. S. p. 111. 



Two semi-cells, Plate LVI, figs. 4, 5, differing somewhat 

 from those figures on Plate XXXV. 



From Minnesota. 



M. EABENHORSTII, Kirch. Plate LVI, fig. 9. 



Cells as long as broad, small, three-lobed ; terminal cell 

 not much wider than the lateral lobes, widened from the 

 base to the end, apex concave, angles terminating with two 

 short teeth ; lateral lobes divided by a wide, almost right- 

 angled sinus, each half somewhat narrowed towards the 

 end 5 apex indented, a small tooth at each angle. Mem- 

 brane smooth. 



Diameter of cell 85 /* ; length 88 //. 



Thus reads a free translation of Kirchner's diagnosis. 

 The figure does not represent the type; merely a small 

 form of it. 



Ponds, Minnesota. 



