KEY TO THE SPECIES 35 



XXIX. ROSACEiE (Rose Family) 



Herbs or shrubs with alternate stipulate leaves, usually 5 

 more or less united sepals, as many petals, numerous stamens 

 (with the petals) on the calyx-tube, numerous superior ovaries 

 (sometimes enclosed in the calyx-tube), and fruits various. (See 

 Plant Structures, p. 262.) 



* stems shrubby, at least biennial. 

 ■*- Carpels few, becoming follicles. 



1. Opulaster. Carpels 1 or 2; flowers white, in a short, umbel-like corymb. 



2. Holodiscus. Carpels 5 ; flowers white,.iu ample panicles. 



-t- +■ Carpels tew to many, becoming achenes. 



3. Kunzia. Carpels 1 (rarely 2), large ; flowers yellow, terminal. 



4. Rubus. Carpels many, becoming drupelets ; flowers white, conspicuous. 



5. Dasyphora. Carpels many , becoming dry achenes ; flowers yellow, showy. 



12. Cercocarpus. Carpel 1, becoming an achene with a long plumose tail ; 

 petals none. 



13. Bosa. Carpels several, becoming bony achenes inclosed in the fleshy 

 receptacle ; flowers large and showy. 



* * Stems herbaceous. 



-1- Carpels borne on an enlarged pulpy edible receptacle. 



6. Fragaria. Carpels many; flowers white, conspicuous. 



-i- -i- Carpels dry achenes ; style deciduous, receptacle not enlarged. 



7. Argentina. Carpels many; style lateral; stems creeping, with pinnate 

 leaves; flowers yellow. 



8. Potentilla. Carpels many; style terminal or nearly so ; leaves pinnate or 

 palmate ; flowers yellow. 



9. Drymocallis, Carpels many ; style basal ; stems erect, with pinnate leaves ; 

 flowers yellow or yellowish. 



<--(--(- Carpels dry achenes ; style persistent ; leaves interruptedly pinnate. 



10. Geum. Carpels many; style Jointed above, the upper part deciduous; 

 flowers yellow. 



11. Sieversia. Carpels many; style not jointed, plumose or naked. 



1. OPULASTER (NiNB-BAKK) 



Branching shrubs, with simple palmately lobed leaves, white flowers in umbel- 

 like corymbs, campanulate calyx, 5 petals, 20-40 stamens inserted with the petals, 

 and 1-5 pistils. 



1. Opnlaster monogynus (Terr.) Kuntz (Colorado Nine-bark). Stems 

 with shreddy bark, 7-15 dm. high; leaves glabrous and bright green, 2-3 cm. long, . 

 ovate-cordate, the lobes toothed; inflorescence a capitate-corymb, nearly glabrous; 

 petals obovate, exceeding the glabrous sepals ; carpels 8 (rarely only 1), united 

 below, divergent above. Frequent in mountains and canons. 



