KEY FOR MARCH, APRIL AND MAY 



203 a Flowers % in. or more long; leaves 1-3 in. long 



Uvularia. p 133 

 b Flowers %-% in. long; leaves 2-6 in. long.Salomonia. p 136 



Terrestrial Green Herbs With Distinctly Yellow Flowers 



204 a Flowers yellow, not at all red or merely with a yellow 



center 205 



b Flowers not yellow 251 



205 a Flowers very irregular, one petal modified into a swollen 



sac i in. or more long Cypripedium. p 138 



b Flowers not completely as in a 206 



206 a Leaves in i or 2 whorls on an upright stem ; flowers 



Vz-i in. broad, in umbels Medeola. p 136 



b Plants not completely as in a 207 



207 a Leaves grass-like; perianth greenish outside . Hypoxis. p 136 

 b Leaves not grass-like 208 



208 a Flowers very small, usually sessile, arranged in a 



more or less compact head 209 



b Flowers not completely as in a 220 



209 a Leaves 3-foliolate 210 



b Leaves not 3-foliolate; heads subtended by an involucre 



of green bracts 211 



210 a Stipules toothed at the base; achenes black when ripe 



Medicago lupulina. p 175 

 b Stipules not toothed at the base Trifolium. p 175 



211 a Leaves all basal, pinnatifid; flowering stalk hollow 



Taraxacum, p 219 

 b Plants not completely as in a 212 



212 a Stem very hairy; leaves bract-like, the basal leaves 



wanting at flowering time Tussilago. p 238 



b Plants not completely as in a 213 



213 a Plant white-woolly throughout; leaves entire . Gifola. p 233 

 b Plants not completely as in a 214 



214 a When open all flowers in the head irregular with 



strap-shaped corollas, as in the Dandelion 215 



b When open only the outer flowers in the head irregular, 



the inner ones regular and tubular, as in the Daisy. . 218 



215 a Flowering stalk with i head 216 



b Flowering stalk with 2 or more heads 217 



216 a Basal leaves entire; head 1-2 in. broad 



Hieracium pilosella. p 220 

 b Basal leaves usually toothed or pinnatifid; heads ^4-% 



in. broad Adopogon carolinianum. p 219 



217 a Basal leaves with purplish veins; stem leaves not clasp- 



ing at the base Hieracium venosum. p 220 



b Basal leaves not with purplish veins; stem leaves clasp- 

 ing at the base Adopogon virginicum. p 219 



16 



