By Thomas Bruges Flower, Esq. 



77 



Locality. On and in stagnant water. A. Fl. June. Area, 1, 2, 

 3, 4, 5. In all the Districts, but not common. Fronds thin, pellucid, 

 elliptic-lanceolate, caudate at one end, at the other serrated. Roots 

 solitary. Fronds half-an-inch long, proliferous at right angles. 



2. L. minor, (Linn.) lesser Duckweed. Engl. Bot. t. 1095. 

 Reich Icones, vii., 14. 



Locality. Abundant in stagnant water-ponds and ditches. A. 

 Fl. June, July. Area, 1, 2, 3, 4, 5. Recorded in all the Districts. 

 About a line-and-a-half long, of a thick, succulent, but compact 

 texture, slightly convex beneath. The young fronds constitute the 

 Lemna arrhiza of the French Authors. 



3. L. gibba, (Linn.) gibbous Duckweed. Gihbus (Lat. 1 ) means 

 convex or haunced out, in allusion to the convex lower surface of the 

 frond. Engl. Bot. t. 1233. Reich Icones, vii., 4. Telmatophace, 

 Schl. Endl. 



Locality. On stagnant water. A. Fl. June, August. Area, 1, 2 S 

 3, 4, 5. In all the Districts, but not frequent. Size of L. minor, 

 but readily distinguished by its gibbous or even hemispherical lower 

 surface, which is, moreover, white, pellucid, and beautifully cellular, 

 upper side plane, green opaque. 



4. L. polyrhiza, (Linn.) many-rooted or greater Duckweed. 

 Polyrhiza is compounded of polus, many, and r/iiza, sl root, in 

 allusion to the tuft of roots in this species. Engl. Bot. t. 2458. 

 Reich Icones, vii., 15. Spirodela, Sch. Endl. 



Locality. Stagnant water. P. Flowers have not been seen in 

 Britain. Area, 1, 2, 3, 4, 5. The largest of all the species, half-an- 

 inch long, and nearly as broad, succulent, firm, a little convex below, 

 where, and at the margin above, the frond is of a deep purple colour. 

 Roots numerous, clustered. 



ORDER. POTAMOGETONACE.E. (JUSS.) 



POTAMOGETON, (LlNN.) PoND-WEED, 



Linn. CI. iv., Ord. iii. 



Name. From poiamos, a river, and geiton, a neighbour, in allusion 

 to the genus growing near, or rather in, water. 1 



1 Chamisso and Schlechtendal have well illustrated this genus. See Linnaa, 

 ii., p. 159. 



