MICRASTERIAS. 127 



the middle, angles furnished with two or three small papillae; 

 lateral lobes nearly equal, bisected, and again divided, each 

 lobule with apex furnished with two papilla-like points. 



Var. HAMATA, Wolle. Plate XLIV, figs. 3, 4. 



In this variety, the polar lobe is not conferta, compact, 

 close against the adjoining lobes, as in the true form, but 

 widely separated in the whole length ; the open space is pro- 

 duced by the contraction of the lobe below the apex, thua 

 giving it a hamate form. 



Diameter 80-100 //., length slightly more. 



Ponds, Mount Everett, Mass. 



The only locality from which. I received the typical form is 

 Aiken, S. C., the same from which Wood had it. This species 

 was first known in Sweden, and described by Cleve, as M. 

 crenata. Lundell separated it from that species and named 

 it M. conferta; it was so recorded with figure, in his De Des- 

 midiaccis, quce in Suecia inventce. sunf, published 1871, ante- 

 dating Wood's contribution by at least one year; having a 

 priority claim, Lundell's name is preferred. The membrane 

 is distinctly and largely punctate, not granulate, except when 

 in old condition. 



M. TRIANGULARIS, Wolle. Plate XLIV, figs. 1, 2. 



Cells large, orbicular or oblong; semi-cells five lobed. 

 Polar lobe triangular, apex and sides nearly straight and 

 nearly equal, the angles mucronate. The lateral lobes similar, 

 twice bisected, apices of the lobelets emarginate or furcate. 



Diameter 170-200 /*. 



I found plants recognized as belonging to this new species 

 in three distinct localities: ponds, Broad Mountain, Pa., 

 Ocean Beach and Bamber, N. J., and Florida. They vary 

 somewhat in outline and details of intersections, but all have 

 the same broad more or less triangular terminal lobe with 

 mucronate angles. Fig. 1 is the typical Pennsylvania form ; 

 fig. 2 the Florida type. The New Jersey plant had stouter 

 terminal lobes, and the ultimate intersections of the lateral 

 lobes were intermediate between the two. 



SECTION V. Cells oblong. 



M. JENNERI, Ralfs. Plate XXXVII, figs. 1, 2. 



Cells oblong, minutely granulated ; semi-cells five parted, 

 lobes closely approximate, cuneate lateral ones obscurely 

 bipartite ; the subdivisions emarginate. 



Diameter 100-150 p. 



