Order 47.— ROSACEA. 339 



19. RITBUS, L. Bramble. (Celtic rub, red ; the color of the fruit 

 of some species.) Calyx spreading, 5-parted ; petals 5, deciduous; sta- 

 mens 00, inserted into the border of the disk; ovaries many, with 2 

 ovules, one of them abortive ; achenia pulpy, drupaceous, aggregated 

 into a compound berry ; radicle superior. — if Half shrubby plants. Sts. 

 usually (•>;, and armed with prickles. Inflorescence imperfectly centri- 

 fugal. Fr. esculent. 



§ Fruit inseparable from the juicy, deciduous receptacle. Blackberries (a) 



a Stems (mostly) erect, stout, armed with stout, recurved prickles Nos. 1, 2 



a Stems procumbent, trailing, mostly with slender, minute prickles Nos. 3 to 5 



§§ Fruit separating from the dry, persistent receptacle. Raspberp.ies (b) 



b Leaves simple, lobed. Not prickly Nos. 6 to 8 



b Leaves compound. — Stems not prickly, herbaceous No. 9 



— Stems prickly, shrubby. — Corollas single Nos. 10 — 12 



— Corollas double No. 13 



1 R. villdsus Ait. High Blackberry. Pubescent, viscid and prickly ; st. an- 

 gular ; Jfts. 3 to 5, ovate, acuminate, serrate, haiiy both sides ; petioles prickly ; cal. 

 acuminate, shorter than the petals; rac. leafless, about 20-flowered. — A well known, 

 thorny shrub, Can. and TJ. S. Sts. tall and slender, branching, recurved at top, 

 3 to 6f high. Lfts. 21 to 4' by 14- to 2\', terminal one on a long petiolule, the 

 others on short ones or none. Pedicels slender, 1' long. Petals white, obovate 

 or oblong, obtuse. Pr. consisting of about 20 roundish, shining, black, fleshy 

 carpels, closely connected into an ovate or oblong head, subacid, well-flavored, 

 ripe in Aug. and Sept. 



p. frondosus Torr. Lfts. incisely serrate ; rac. with a few simple lvs. or leafy 

 bracts at base ; fls. about 10 in each cluster, the terminal one opening first, 

 as in all the species, the lowest next, and the highest but one last. Pr. mora 

 acid and with fewer carpels. (R. frondosus Bw.) 



7. uumifusds T. & G-. St. procumbent or trailing ; lvs. smaller ; ped. few- 

 liowered. — Often occurs southward with the erect forms, and with R. trivia- 

 lis, from which it is sometimes hard to be distinguished. 



2 R. cuneifolius Ph. Sand Elackderry. St. erect, shrubby, armed with re- 

 curved prickles ; lvs. 3-foliate, and with the young branches and pet. pubescent 

 beneath ; lfts. cuneate-obovate, entire at base, dentate above, subplicate, tomentous 

 beneath ; rac. loose, few-flowered. — A low shrub, 2 to 3f high, in sandy woods, L. I. 

 to Pla. Petioles often prickly. Lfts. rarely 5, 1 to 2' long, \ as wide, obtuse, 

 or with a short acumination. Petals white or roseate, 3 times as long as the caL 

 Fr. black, juicy, well-flavored, ripe in Jl., Aug. Pis. May, Jn. 



3 R. hispidus L. St. slender, reclining or prostrate, hispid with retrorse bristles ; 

 lvs. 3-foliate, rarely quinate. smooth and green both sides ; lfts. coarsely serrate, 

 obovate, mostly obtuse, thickish, persistent ; ped. corymbous, many flowered, with 

 filiform pedicels aud short bracts; fls. and fr. small. — In damp woods, Can. to Car. 

 Sts. slender, trailing several feet, with suberect branches 8 to 12' high. Lfts. 1 to 

 2' long, J as wide, nearly sessile, persistent through the winter. Pis. white. Fr. 

 dusky-purple, sour. May, Ju. (R. sempervirens Bw.) 



/?. setoscs T. & G. Lfts. oblanceolate, rather narrow, 1& to 2+' long, tapering, 

 and (like variety a) entire at base, sharply serrate above. Fr. red. (R. seto- 

 sus Bw.) 



4 R. Canadensis L. Northern Dewberry. St. procumbent or trailing, a 

 little prickly ; lvs. 3-foliate, rarely quinate, lfts. elliptical or rhomboid-oval acute or 

 acuminate, thin, unequally cut-serrate; pedicels solitary, elongated, somewhat 

 corymbed; //-. large, black. — Common in dry, stony fields, Can. to Va., trailing 

 several 3-ards upon the ground. Lfts. light green and membranous, nearly sessile, 

 1 to 14- ' long, ^ as wide. Fls. large, on slender pedicels. Petals obovate, white, 

 twice as long as the calyx. Fr. $ to 1' diam., very sweet and juicy in JL and 

 Aug. Fls. May. (R. trivialis Ph.)" 



5 R. trivialis Mx. Southern Dewberry. Procumbent, trailing, with root- 

 ing runners, shrubby, armed with bristles and recurved prickles ; lvs. 3-foliate and 

 quinate, persistent, lfts. coriaceous, ovate-oblong or oval, acute or obtuse, sharply 

 serrate ; ped. 1 to 3-flowered ; fls. large, pet. roundish-obovate ; sep. oblong, obtuse, 



