DIDYNAMIA GYMNOSPERMIA. 385 



R. repens : leaves ternate ; leaflets cuneate, 3-lobed, incisely dentate ; 



middle one petiolate ; main stems prostrate ; flowering ones erect ; 



peduncles sulcate ; calyx appressed. 

 HAB. Wet meadows. " June Sept. 1J-; stem 1 2 feet high; Jl 



middle-sized 



258. BRASENIA. Water-target. 



B. hydropeltis. 



HAB. Ponds. July Aug. Qj. ; floating; leaves oval, centrally 



peltate, very entire ; purp. and gelat. beneath ; Jl. sol., purp., on 



long pedunc. 



DIDYNAMIA. 

 GYMNOSPERMIA. 



* Calyx mostly 5-cleft, subre-gular. 



Genera. 



259. TEUCRIUM. Upper lip of the cor. wanting, but a fissure in its 

 place, through which the stamens are exserted. 



260. MENTHA. Cor. subregular, 4-lobed ; the broader segment emar- 

 ginate; stain, erect, distant. 



261. HYSSOPUS. Lower lip of the corolla 3-parted ; middle segment 

 crenate ; stamens straight, distant. 



26-2. NEPETA. Calyx arid, striate tube of the cor. rather long, in- 

 termediate segment of the lower lip crenate, margin of the orifice 

 reflexed ; stamens approximate. 



263. LAMIUM. Upper lip of the cor. vaulted, entire; lower lip 2- 

 lobed, toothed on each side. 



264. GALEOPSIS. Upper lip of the cor. vaulted, notched; lower lip 

 3-lobed, 2-toothed above. 



265. STACHYS. Upper lip of the cor. vaulted, lower lip 3-lobed ; the 

 lateral lobes reflexed; stamens reflexed to the sides after flower- 

 ing. 



266. LEONURUS. Calyx 5-angled ; upper lip of the cor. entire, flat, 

 erect ; lower lip 3-parted ; middle segment entire ; anthers sprinkled 

 with shining dots. 



267. GLECHOMA. Upper lip of the corolla bifid; anthers approach- 

 ing each other in pairs, and forming a cross. 



268 MARRUBIUM. Calyx 10-ribbed ; upper lip of the corolla linear, 



straight, cleft. 



>69. PYCNANTHEMUM. Heads surrounded by an involucrum of 

 many bracts ; calyx tubular, striate, upper lip of the corolla nearly 

 entire; lower lip 3-cleft; stamens nearly equal, distant; cells of 

 the anthers parallel. 



