110 KOSACE^E. (ROSE FAMILY.) 



1. I>. I>racliylo1>llS, Bcnth. Nearly glabrous, erect (l-4 high); 

 partial petioles 6-15 pairs ; leaflets 20 - 30 pairs ; stamens 5 ; pods oblong or 

 lanceolate, curved, scarcely 1 long, 2-6-secdcd. 1|. (Darlingtonia brachyloba 

 & glandulosa, DC.) Prairies and alluvial banks, Illinois and southwestward. 



36. SCHRiNKIA, Willd. SENSITIVE BRIAR. 



Flowers polygamous. Calyx minute, 5-toothed. Petals united into a funnel- 

 form 5-cleft corolla. Stamens 10-12, distinct, or the filaments united at the 

 base. Pods long and narrow, rough-prickly, several-seeded, 4-valved, i. e. the 

 two narrow valves separating on each side from a thickened margin. Peren- 

 nial herbs, the procumbent stems and petioles prickly, with twice-pinnate sensi- 

 tive leaves of many small leaflets, and axillary peduncles bearing round heads 

 of small rose-colored flowers. (Named for Schrank, a German botanist.) 



1. S. UllCinata, Willd. Prickles hooked; partial petioles 4-6 pairs; 

 leaflets elliptical, reticulated with strong veins beneath ; pods oblong-linear, nearly 

 terete, short-pointed, densely prickly (2' long). Dry sandy soil, Virginia, 

 Illinois? and southward. June -Aug. 



2. S. angUStata, Torr. & Gray. Leaflets oblong-linear, scarcely veined; 

 pods slender, taper-pointed, sparingly prickly (about 4' long). With the pre- 

 ceding. 



ORDER 39. ROSACEJE. (ROSE FAMILY.) 



Plants with regular flowers, numerous (rarely few) distinct stamens insert- 

 ed on the calyx, and 1 - many pistils, which are quite distinct, or (in the Pear 

 tribe) united and combined with the calyx-tube. Seeds (anatropous) 1 -few 

 in each ovary, without albumen. Embryo straight, with large and thick coty- 

 ledons. Leaves alternate, with stipules. Calyx of 5 or rarely 3-4-8 

 sepals (the odd one superior), united at the base, often appearing double 

 by a row of bractlets outside. Petals as many as the sepals (rarely want- 

 ing), mostly imbricated in the bud, and inserted with the stamens on the 

 edge of a disk that lines the calyx-tube. Trees, shrubs, or herbs. This 

 important family comprises three principal suborders, viz. : 



SUBORDER I. AMYGDALEJE. THE ALMOND FAMILY. 



Calyx entirely free from the solitary ovary, deciduous. Style terminal. 

 Fruit a drupe (stone-fruit). Trees or shrubs, with simple leaves, the bark 

 exuding gum, and the bark, leaves, and kernels yielding the peculiar flavor 

 of prussic acid. Stipules free. 

 1. PRUNUS. Stone of the drupe smooth, or merely furrowed on the edges. 



SUBORDER II. ROSACE^E PROPER. 



Calyx free from the ovaries, but sometimes enclosing them in its tuln>. 

 Pistils few or many (occasionally single). Stipules commonly united with 

 the petiole. 



