140 



Scliwcin., a resinous form, and R. Eugclnianui, S. Watson, a form 



with oblong fruit. 



After having carefully examined several European and Asiatic 

 specimens of this species and a large number of American forms, 

 including the original R, Sayi in the Pliila. Academy, I cannot 

 find any character of recognized value to separate them. The 

 forms of the New World are usually somewhat more resinous but 

 not constantly so, and the fruit probably more inclined to be 

 globose. These variations are far from being uncommon in other 

 species, as a result of differences in environment. To multiply 

 species therefore, because one specnnen has a few more hairs or a 

 few less glands than another, or perchance fruit of a slightly differ- 

 ent shape, seems uncalled for. 



Rosa acicnlaris is from one to three feet high, more or less 

 prickly, sometimes densely so; prickles rarely enlarged about 

 nodes simulating geminate spines; leaflets 3 to 7, usually 5 to 7, 

 broadly elliptical to oblong-lanceolate, mostly obtuse or slightly 

 cordate at base, flowers solitary; fruit sometimes globose but 

 usually more or less oblong. 



5. Rosa Nutkaiia, Prcsl, 1857, ranges from wx^stern Montana, 

 Idaho, Oregon and Washington northward and probably south- 

 ward. In its densely rcsuious forms with stout recurved spines 

 and broad stipules, it is not easily confounded with any other 

 species. Forms, however, occur which are nearly or quite desti- 

 tute of glands, with straight, slender, sometimes ascending spines, 

 frequently absent or reduced to a single one in the upper 

 part of the stem, leaflets larger and simply toothed, and which 

 are difficult to separate from unarmed forms of /v. aciailaris. 

 The fruit of R, Nntkana, large, coriaceous, thick-walled and 

 fibrous, with seeds larger than in any other species, serves to 

 distinguish it. 



6. Rosa pisocarpa^ Gray 1882 (? R. Woodsii, Lindley 1820). 

 In '' PrhniticB'' p. 432, M, Crcpin describes R, Fcudkri from a 

 specimen collected in New Mexico. This description is based on 

 a stunted g"rowth with straight slender spines, small leaflets and 

 solitary flowers. He is now, however, inclined to regard it as be- 

 ing practically the same as R. pisocarpa, in which opinion I fiilly 

 concur; but Dr. Sereno Watson considers them quite distinct. 



