1922] 



PFEIFFER MONOGRAPH OF THE ISOETACEAE 111 



Corm 3-lobed; leaves 10^40 (rarely 60). 12-40 cm. long, light 

 green, firm but not stiff, tapering to apex, with wide membrana- 

 ceous margin at base gradually narrowed to disappearance 1-2 

 cm. above sporangium level; stomata present in upper parts of 

 leaves; peripheral strands variable, but chiefly 6 plus accessory 

 strands ; ligule longer than wide ; sporangia 4-6 mm. long, lightly 

 marked with sclerenchyma cells ; velum none ; megaspores white, 

 564-680 n (rarely 800) in diameter, densely crowded on all faces 

 with small warts or tubercles ; commissural ridges prominent and 

 wide ; microspores 27-37 n long, usually with slightly crenulate 

 margins and with low crest. 



Distribution: Montpellier, Herault, France. 

 Specimens examined: 



France: Grammont, near Montpellier, December, 1820, Ballard 

 (Gray Herb.) ; Montpellier, ex Herb. Engelmann (Mo. Bot. 

 Gard. Herb.) ; mare de Grammont pres Montpellier, Delile 

 (N. Y. Bot. Gard. Herb.) ; lac de Grammont, August, 1837, 

 de Gerard (Mo. Bot. Gard. Herb.) ; Montpellier, Grammont, 

 21 March, 1840, Bubani (U. S. Nat. Herb.) ; Montpellier, 

 1842, Wanderley (Mo. Bot. Gard. Herb.); Montpellier, 

 Grammont, 30 June, 1842, without collector (Mo. Bot. Gard. 

 Herb.) ; pools of plateau of Roquehaute, 7 June, 1863, Durieu 

 21 (N. Y. Bot. Gard. Herb.) ; pond near Montpellier, 8 June. 

 1857, Cosson (Gray Herb., Mo. Bot. Gard. Herb., and N. Y. 

 Bot. Gard. Herb.) ; near Beziers (Herault), and Juire, 1879, 

 Gautier (N. Y. Bot. Gard. Herb.) ; Montpellier, 1866, Cosson 

 (Mo. Bot. Gard. Herb.); marsh, Roquehaute near Beziers 

 (Herault), 3 June, 1862, Cosson (Mo. Bot. Gard. Herb., N. 

 Y. Bot. Gard. Herb., and Gray Herb.) ; pool, Roquehaute, 

 June, 1862, Durieu (Mo. Bot. Gard. Herb.); "in almost all 

 the ponds of the volcanic plateau of Roquehaute, Herault," 

 17 May, 1864, Motelay (Mo. Bot. Gard. Herb.) ; ponds of 

 Roquehaute, 11 May, 1864, Cheveneau (U. S. Nat. Herb.) ; 

 pond of Roquehaute near Beziers, June, 1869, Cheveneau 

 (Gray Herb.) ; near Montpellier, Grammont, 6 June, 1884, 

 without collector (U. S. Nat. Herb.); pond at Grammont 

 near Montpellier, November, 1876, Duval-Jouve (Gray 

 Herb.) ; Grammont near Montpellier, 10 May, 1888, Herb. 

 Fac. Scient. Monsp. (U. S. Nat. Herb.); Portiragnes 

 (Herault), ponds in plateau of Roquehaute, 1 April, 1888, 



