MB. W. JOSHUA ON BUEMESB DESMIDIE.B. 637 



brachio) 180 p, latit. (cum spinis) 217 p : isthmi latit. 25 p : 

 expansio lobi polaris 52 p. 



Large, orbicular, smooth ; semicells distinctly 4-lobed ; 

 lobes subdivided ; slightly inflated at base ; much attenuated ; 

 deeply furcate at ends, forming straight rays ; end-lobes narrow- 

 cuneate, divergent, and attenuated. Differing from M. radiosa, 

 Ralfs, by its larger size and linear form of subdivisions. Length, 

 without arm, ISO p ; breadth, with sp., 217 p ; width of isthmus 

 25 p ; spread of polar lobes 52 p. 



M. ceratofeba, nob., Journal of Botany, vol. xxiii. p. 34, 

 tab. 254. figs. 4«, 46. 



M. euastboides, n. sp. (Plate XXII. fig. 14.) 

 M. mediocris, subquadrata ; semicellulis 5-lobatis, lobo termi- 

 nali truncato, profunde constrictis, marginibus denticulatis 

 superficie spinis brevibus ornatis. Longit. 103 p, latit. 90 p. 



Medium ; subquadrate ; semicells 5 lobed, deeply constricted, 

 denticulate at edges, and furnished with short spines on surface ; 

 end-lobe truncate; length 103 p, breadth 90 p. In appearance 

 resembling some of the forms of Euastrum verrucosum ; but pro- 

 bably a new Micrasterias allied to M. mahabuleshwarensis, Hobson, 

 and M. Wallichi, Grun. 



7. Euastbum, Ehrenb. 



E. ausalum, Ralfs. 

 E. ausalum, var. ampliatum. 

 E. slnuosum, Lenorm. 

 E. didelta, Ralfs. 



E. binale, Ralfs, n. f. cbassum. (Plate XXIII. figs. 11, 12, 

 & 13.) 



E. tubgidum, Grun. 



E. substellatum, Nordst. 



E. gemmatum, Breb., MONOXcroLUM, Nordst. 



E. decedens, Reinsch. 



E. cuneatum, Jenner. 



E. spinulosum. Belponte, f. inebmius, Nordst. 



E. oblongum, Grew, f. scbobiculatum, Nordst. 



E. elegans, Breb. 



E. sublobatum, Breb. 



E. HrrocHONDBUM, Nordst. 



