DICOTYLEDONS. LABIATE. ThytllUS. 217 



2. S. ambigua, whorls of 6 flowers, leaves oblongo-cordate acute 

 petiolate, stem hollow. (Sm.) p. 183.- Fields. 



3. S. palustris, whorls of 6 flowers, leaves linear-lanceolate semi- 

 amplexicaul. p. 183. Marshes. 



4. S. arvensis, whorls of 6 flowers, stem weak, leaves heart-shaped 

 obtuse crenate slightly hairy, cor. scarcely longer than the cal. 

 p. 183. Corn-fields. 



13. BALLOTA. 



Cal. with 10 rihs and 5 teeth. Upper lip of the Cor. concave, 

 notched ; lower one trifid ; middle lobe the largest, emarginate. 



1. B. 72'igra, leaves ovate undivided serrated, calyces dilated up- 

 wards subtruncated, the teeth patent. (Sm.) p. 184. Waste 

 places. 



14. MARRUBIUM. 



Cal. with 10 ribs and 5 or 10 spreading teeth. Upper lip of the 

 Cor. cloven, linear, straight; lower one trifid; middle segment 

 the largest, emarginate, 



1. M. vulgare, stem erect, leaves roundish ovate toothed wrinkled, 

 cal. with 10 setaceous hooked teeth, p. 184. Waste places. 



15. LEONURUS. 



Cal. with 5 angles. Upper lip very hairy above, entire ; lower 

 one reflexed, 3-partite. Anthers sprinkled with shining dots. 



1. L. Cardiaca, leaves petiolate, the lower ones crenato-lanceolate 

 3-lobed, upper ones entire, p. 184. Among rubbish. 



SECT. II. Calyx 1-lipped. 



16. CLINOPOD1UM. 



Involucre (bracteas of many linear- acuminate leaflets placed un- 

 der the cal. Upper Up of the cor. erect, emarginate ; lower 

 one the largest, emarginate. 



1. Cl. vulgare) leaves ovate obscurely serrated, whorls hairy, 

 bracteas setaceous, pedicels branched, p. 184. Banks. 



17. ORIGANUM. 



Calyces collected, by imbricated bracteas, into a spicate, qua- 

 drangular cone. Upper lip of the cor. straight, notched ; the 

 lower one in 3 nearly equal lobes. 



1. O. vulgare, spikes roundish panicled conglomerate glabrous, 

 bracteas ovate longer than the cal. Cleaves ovate entire, p. 185. 

 Bushy places. 



18. THYMUS. 



Cal. closed with hairs at the mouth. Cor. shortly 2-lipped ; upper 

 one notched ; the lower one the largest, subemarginaie. 



