HEXANDRIA.— TRIGYNIA. 163 



rous ; racemes leafless ; leaves lanceolate ; sheaths 

 cylindrical. 

 HAB. Wet places. June. Root large; stem 2 ft. 

 high ; fl. semiverticil. 



t | Valves toothed. 



u. R. acutus : valves oblong, somewhat toothed, all of 

 them graniferous ; leaves cordate-oblong, acumi- 

 nate, whorls leafy. 

 HAB. Waste places. May. Stem 2— 3ft. high ; low- 

 er leav. large, §. \ 



7. R. obtusifolius : valves dentate, one of them con- 



spicuously graniferous ; radical leaves ovate-cor- 

 date, obtuse ; stem somewhat scabrous. 

 HAB. Woods and fields. June — July. Root brown 

 ext., yell, int.; rad. leav. very large, §. 



* * Flowers dicecious ; valves grainless. acetosa. 



8. R. Acelosella: leaves lanceolate-hastate, with the 



lobes spreading or recurved. 

 HAB. Fields. May— July. Stem 4—12 in. high; 

 plant acid. §. Pist. Fl. rare. 



TETRAGYNIA. 



261. SAURURUS. Lizard's-tail. Najades? 

 6. cemuus. 

 IJAB. In water. July— Aug. y.. Stem 1 8 in.— 2ft. 



high ; leav. alt., petiol. cordate, spike 3 — 6 in. long, 



while, cal. tub. 



POLYGYRIA. 



265. ALISMA. Water-Plantain. Alismacev. 



\. Plantago : leaves ovate-cordate, acute or obtuse, 



9-ncrved ; flowers in a compound verticillate pant 



cle : "fruit obtusely triangular. 

 HAB. In water. July — Aug. If. Leav. rad. 9 



nerv. : petiol. ; pan. large ; fl. wh. 

 3. parviflora : leaves oval, 5 — 7-nerved, acuminata 



flowers very small. 



