SPECIES OF DESMIDS. 93 



mm. Sinus acute inwardly .... . . thithophorum, 80 



mm. " rounded and widened inwardly . . phaseolus, 8i 



mm. " rounded, but not widened inwardly, pseudogranatum., 158 

 nn. Margins crenate or dentate (00). 



nn. Margins smooth; centre with one verruca; semi-cell elliptical:, 

 diameter ysVo'"- (''3y") • • '■ • • • bireme, 82. 



vo. Ends truncate; diametery-|^ in. (33/^) or larger {pp). 

 00. " " diameter -^ in. (28/() or smaller (7-r). 



00. Ends rounded, dentate . . . . . . . Lagoense, * 



//. About i-|- times longer than wide; diameter 1^ to ^-^ in. (33-50/^) 



triplicatum ■]T,;speciosum, 87 

 pp. About \ longer than wide; diameter -^ to -j-^ in. (65-7oyu), 



supraspeciosum, 88 

 //. About \ longer than wide; diameter -^\-^ in. (soyu), 



pychnochondnim, 89 

 rr. Diameter -g^-j to yJjTr (2o-26/<); ends 4 crenate, sides 4-6 crenate, 



subcrenatum, 84. 

 ''''• " TTiVo-to tAt (^°~^S^)' sides nearly straight, 



Kjdlmaiiii, 87 

 rr. " y^Vo to y-gVff (i4-2Sy");granulesnotradiate; end4crenate, 



Blyttii, 87 



j-j-. Marginal teeth numerous, long, pointed or aculeate, Eloiseanum, 85 

 «. ,_ 17, emarginate-truncate . qiiadrifariiim, 87 



jj. Margins crenate (#). 



/^. Basal inflation granulate in vertical lines {uii). 



tt. " " with scattered granules . pseudopectiiwides, 89 



tt. " " without granules, the marginal in 8 radiating lines, 



nasKtinn, 89 

 uii. Sinus widening outwardly; granules geminate in rows, 



pectiiwides, 88 

 UII " not widening outwardly; cell oblong, diameter —W {TiZ), 



pulchej-ritni/m, 90 

 uii. " " " cell orbicular, diameter -jJ-^ (50/^), 



radiosiim, 90 

 vv. End truncate i^wiv). 



w. End not truncate {zz). • 



M/?e'. Diameter T^ in. (50/^) or larger (.r.v). 

 ■a/w. Diameter smaller than (50/^), ^L- in. ( rr). 



*Journ. R. Micr. Soc, Dec, 1SS5. 



