kosaceAe (rose family) 495 



pistils below. Ovaries hairy, becoming bony achenes in fruit. — Shrubs, usually 

 prickly, with odd-pinnate leaves, and stipules adnate to the petiole ; stalks, foli- 

 fige, etc., often bearing aromatic ulaiids. Many oi the species highly variabie 

 and often indeterminable from imperfect specimens. (The ancient Latin name.) 



('. styles coherent in 11 protruding column, ao lon^ as the stiameiis . . 1. R. aeUgera. 

 II. Styles distinct h. 



b. Sepals connivent after flowering-, persistent; pedicels and receptacle 

 naked c. 

 (J. Prickles scattered or none, the infra-stipular when present not en- 

 larged. 

 Leaf-rhaehis glandular-piiherulent or -bristly. 

 Fruit pyriform, obovoid or oblong, top-shaped at base . . 2. i?. adcuUtria. 

 Fruit subglobose, obtuse or rounded at base (2) R. acicularis, /. Bov/rgeawlami. 

 Leaf-rhacbis softly and finely villous or tonientulose ; glandular 

 hairs merely occasional or none. 



Prickles numerous, scattered ; leaflets 7-11 Z. B. praMncola. 



Prickles occasionally present on main stem but mostly few or 



none ; leaflets 6-7 i. H. blanda. 



u. Prickles not wholly uniform, the infra-stipular somewhat stouter. 

 Calyx-lobes essentially entire. 

 Calyx-lobes 1-1.5 cm. long. 

 Leaves G-IO cm. long ; leaflets pubescent beneath ; stem armed 



chiefly near the nodes 5, iS. WoodsH. 



Leaves 2-i cm. long; leaflets essentially glabrous ; stem ex- 

 cessively spiny throughout . " . . . i. li. apinosissima . 

 Calyx-lobes 2-2..5 cm. long ... . .7. H. cinnamomea. 



Outer calyx-lobes conspicuously pinnatifid S. li. canina, 



b. Sepals spreading after flowering, deciduous from the mature fruit ; 

 recft^tacle and pedicels more or less hispid or tomentose. 

 Leaflets thick, evergreen or nearly so ; receptacle tomentose 9. Ji. bracteata. 



Leaflets membranaceous ; receptacle not tomentose. 

 Leaf-rhachis very glandular. 

 Prickles strong, hooked ; leaflets rarely 2 cm. long . . 10. R, rubiginosa. 



Prickles weak, acioular, often gland-tipped ; leaflets 8-6 cm. 



long 11. iJ. galliaa. 



Leaf-rhachls puberulent or glabrous, scarcely if at all glandular. 

 Young growth densely covered, even into the inflorescence, 



■mfix needle-like prickles \i. B. niUda. 



Young growth armed at the nodes or not at all. 

 Stipules narrowly linear, their free auricles merely short- 

 lanceolate teeth ; leaflets serrulate ; infra-stipular pilckles 

 short, 2-4 (rarely 6) mm. long, broad-bosed and decidedly 



curved . . 13. 7?. Carolina. 



Stipules more dilated, oblanceolate, their auricles somewhat 

 deltoid ; serratures of the leailets coarser and deeper ; 

 infra-stipular prickles longer. 

 Prickles decidedly curved ; leaflets somewhat shining above 14. R, virgiuiana. 

 Prickles straight or nearly 80 ; leaflets dull above . 15. R. humifis. 



1. R. setlgera Michx. (Climbing or Prairie E.) Stems climbing, armed 

 with stout nearly straight scattered prickles, not bristly ; leaflets 3-5, ovate, 

 acute, sharply serrate, smooth or downy beneath ; stalks and calyx glandular ; 

 flowers ooiymbed ; sepals pointed ; petals deep rose-color changing to white ; 

 fruit globular. — Borders of prairies and thickets, Ont. to Fla., w. to Wise, Neb., 

 and Tex. ; also an escape from cultivation in Ct. July. — Strong shoots growing 

 3-6 m. in a season. 



2. R. acicularis Lindl. Stems 3-12 dm. high, very prickly ; stipules usually 

 dilated, glandular-ciliate and resinous ; leaflets 3-7, broadly elliptical to oblong- 

 lanoeolate, sessile and obtuse or subcordate at base, usually pale and somewhat 

 resinous-puberulent beneath, the teeth serrulate; flowers large, solitary (very 

 rarely 2-.3) ; outer sepals usually with 1-2 narrow lateral lobes, not hispid ; fruit 

 obovoid or ellipsoid, top-shaped at base. (B. Engelmanni Wats. ) — Sandy 

 thickets. L. Huron to Minn., Col. , and Ida. (Siber.) 



Var. Bourgeauiina Crfipin. Fruit globose, rounded at base ; leaves some- 

 times smoothish but more often soft-pubescent and resinous-pulverulent beneath. 

 — Ledges, rocky woods, etc., Anticosti to s. Vt., n. Mich., centr 111., Col., and 

 northw. 



3. R. pratincola Greene. Stems low, very prickly ; stiptUes narrow, more or 

 less glandular-toothed above (or even glandular-ciliate) ; leaflets 7-11, broadly 

 elliptical to oblong-oblanceolate, subcuneate at base, somewhat firm and strongly 



