LEGUMINOS^J ROSACEJB 385 



15. CASSIA. SENNA. Fig. 247. 



Our herbs with odd-pinnate, compound leaves and yellow flowers: sepals 

 5, nearly equal; corolla not papilionaceous, nearly regular ; petals 5, stamens 

 510, some anthers usually imperfect: pod often curved, many-seeded. 



C. marilandica, Linn. Smooth perennial, 3-4 ft. : leaflets 6-9 pairs, lance- 

 olate-oblong, mucronate, with a gland at or near base of petiole: stipules 

 deciduous: stamens 10, 3 imperfect, with deformed anthers, the anthers 

 black: flowers showy yellow, short, axillary racemes. Summer. 



16. APIOS. GROUNDNUT. 



Perennial, twining herb, with edible underground tubers: leaves pin- 

 nately 3-7-foliate: flowers in short, dense, often branching axillary racemes: 

 calyx rather 2-lipped: standard broad and reflexed: keel strongly incurved, 

 pushing into the standard, and finally coiled or twisted. 



A. tuberdsa, Moench. Flowers brownish purple, sweet-scented, in dense 

 racemes about 1-3 in. long: no tendrils: juice milky. Summer. In low, 

 moist ground and shady woods. 



XXIX. ROSACES. ROSE FAMILY. 



Herbs, shrubs and trees, much like the Saxif ragacese : leaves 

 alternate, mostly with stipules (which are often deciduous): flowers 

 mostly perfect and polypetalous, the stamens usually perigynous, 

 mostly numerous (more than 20) ; pistils 1 to many : fruit an achene, 

 follicle, berry, drupe, or accessory. A very mixed or polymorphous 

 family, largely of temperate regions, of about 75 genera and 1,200 

 species. By some writers, divided into three or four families. Common 

 rosaceous plants are rose, strawberry, apple, pear, plum, peach, cherry, 

 blackberry, raspberry, spirea, cinquefoil. 



A. Herbs. 



B. Torus not enlarging. 



c. Carpels many, in a head. 



D. Style deciduous 1. PotentUla 



DD. Style persistent on achene, usually jointed and 



plumose 2. Geum 



cc. Carpels 2: calyx prickly and lobes closing over 



the fruit: 1 or 2 achenes 3. Agrimonia 



BB. Torus becoming fleshy: flowers directly from the 



crown or root .' 4. Fragaria 



AA. Shrubs or trees. 



B. The ovary 1, superior: fruit a drupe 5. Prunus 



BB. The ovaries more than 1. 



c. Fruit 1-seeded drupes aggregated, or achenes. 



