372 



ROSACEAE 



Petals rose or purple; stem densely hispid but not 



glandular. 

 Petals white. 



Inflorescence corymbiform ; fruit black or purple; 



stem prickly. 

 Inflorescence racemose; fruit red. 



Plant not at all glandular hispid; young 

 branches and inflorescence finely tomentose. 

 Plant more or less glandular hispid, especially 

 in the inflorescence. 

 Carpels remaining on the fleshy receptacle, or falling off 

 together with the same, or falling off separately. 

 A. Stems prickly or rarely unarmed; prickles com- 

 paratively few, usually stout, confined to the 

 angles of the stem. 

 I. Suckers erect; stems in age erect, arching or 

 recurved (prostrate in No. 21). 

 Leaflets laciniate. 

 Leaflets not laciniate. 



Leaves white-tomentose beneath. 

 Leaves not white-tomentose beneath. 

 Inflorescence densely glandular; with 

 long stipitate hairs. 

 Sepals ovate, abruptly acuminate; 

 stem strongly angled. 

 Inflorescence corymbose; terminal 

 leaflet of the sucker broadly 

 cordate. 

 Inflorescence usually elongate 

 racemiform; terminal leaflet of 

 the suckers elongate-cordate 

 or ovate. 

 Sepals lanceolate, long acuminate. 

 Inflorescence not at all glandular or 

 only slightly so; glands sessile or 

 short stipitate. 

 Leaves densely pubescent beneath. 

 Inflorescence elongated racemose ; 

 young branches angled; 

 terminal leaflets of the 

 suckers not broadly cor- 

 date. 

 Stem very prickly, much 

 branched; prickles of the 

 stem long. 

 Stem sparingly prickly; 

 prickles of the stem short. 

 Inflorescence short, corymbi- 

 form; young branches 

 terete; terminal leafletsof 

 the suckers broadly cor- 

 date. 



4. R. phoenicolasius. 



5. R. occidentalis . 



6. R. Idaeus. 



7. R. strigosus. 



8. R. lacinialus. 



9. R. cuneifolius. 



10. R. salivus. 



11. R. nigrobaccus. 



12. R. allegheniensis. 



13. R. argutus. 



14. R. per grains 



