94. LEIOACE^;. 435 



bent or folded double over the yellow spadix. Abortive pistils 

 very long, both above and below the stamens. W. Cornw. 

 S.Devon. I. of Wight. Channel I. / E. 



Order XCIV. LEMNACE.E. 



Fl. moncecious, 2, in a spath, but without a spadix (rarely 

 found). Perianth 0. Stam. 1 2, distinct. Ovary 1-celled. 

 Style short. Stigma simple. Fr. bladdery, not bursting. 

 Seeds with a coriaceous ribbed testa. Floating, leaflike, small, 

 proliferous ; no distinction of st. or leaf. Fl. very minute. 



1. LEMNA. Spath membranous, urnshaped. Fl. from lateral 

 cleft of fronds. Stam. 1 2. Aiith. 2-celled, didymous 

 (cells bilocular ?). Fronds with capillary roots beneath. 

 Increasing chiefly by offsets. 



2. WOLFFIA. Spath 0. Fl. from upper surface of frond. 

 Stam. 1 ; anth. 1-celled, sessile. Frond very minute, 

 rootless. Increasing by offsets. 



1. LEM:NA Linn. Duckweed. 



1. L. trisul'ca (L.) ; fronds thin pellucid elliptic-lanceolate 

 tailed at one end serrate at the other, roots solitary. E. E. 

 926. R. vii. 15. Fronds half an inch long, proliferous at right 

 angles. Plants submerged, truly annual, producing autumnal 

 bulblets which survive the winter as in the other species. In 

 stagnant water. A. VI. E. S. I. 



2. L. minor (L.) ; fronds obovate compressed opaque, roots 

 solitary blunt. E. ^/1095. R. viii. 14. Fronds 12 lines 

 long, nearly flat beneath, of a compact texture. On stagnant 

 water. A. VI. VII. E.S.I. 



3. L. gib'ba (L.) ; fronds obovate nearly flat above hemispheri- 

 cal and spongy beneath, roots solitary blunt. E. B. 1233. R. 

 vii. 14. Telmatophace Schleid., Endl. Fronds 1 2 lines long, 

 at first flattish, afterwards remarkably gibbous and cellular 

 beneath. On stagnant water. A. VI. VIII. E. S. I. 



4. L. polyrrhiza (L.) ; fronds roundish-obovate, compressed, 

 roots many clustered acute. E. . 2458. R. vii. 15. Spirodela 

 Schleid., Endl. Fronds half an in. long, green above, purple 

 beneath. Fl. iJN^seen in Britain. On water. A. E. S. I. 



u2 



