ROSACK.E. (ROSK FAMILY.) 77 



•3. P. Pennsylvanica, L. (Wn.i> Ki;i. Ciikuuv.) Tree 20 to 30 feet 

 high, with light reil-hrown bark : kaces oblunif-ldnrtuhtte, i>ointed, finely and 

 sharply serrate, shiniiuj, (jrcen and smooth both sides: fruit glolioHC, iiyht red^ 

 very small, with thin aiitl sour Hosh ; stone r/lohn/ar. — From Colorado north- 

 ward, and eastward to Newfoundlaiid and X'irgiiua. 



4. P. emarginata, Walpers, var. mollis, Brewer. Becoming a Hmall 

 tree 25 feet liigh, with l»ark like that of an ordinary Cherry-tree, more ur Usu 

 iroofly-puhcseent : leares dilontj-ovatc to lanceolate, mostly oUuse, crenateh/ ttrru- 

 late, narrowed to a short petiole, with usually one or more glandn near the 

 ba.se of the blade, more or less woolly-pubescent on the under side: fruit glcdK>se, 



black, bitter and astringent; stone icith a thick grooved ridye upon one side. 



Bot. Calif, i. 1G7. Bitter Root Mountains and westward into Oregon and 

 California. 



* * Flowers in racemes terminating leafy branches, hence appearing afler the 

 leaves, late in spring. 



5 P. demissa, Walpers. (Wild Ciikrkv.) An erect slonder .''hrub 

 2 to 12 feet high : leaves ovate or oblong-ovate, abruptly acuminate, mostly 

 rounded or somewhat cordate at base, sharply serrate, usually more or less pubes- 

 cent beneath, with 1 or 2 glands at base : fruit ])urj>lish-black-, or red, sweet and 

 edible, l)ut somewhat astringent ; stone globose. — From the Kocky Mountains 

 westward to the coast. 



6. P. Virginiana, L. (Choke Chekry.) Leaves rarely at all puUs- 

 cent, more fre(jueiilly somewhat cuneate at base: fruit dark red, very astringmt 

 and scarcely edible; the stone more oroid and acutish : otherwise like tlie last, 

 but more diffuse in habit, and preferring stream banks and moist localities. — 

 This species appears to be distributed thronglKJUt the whole of North Amer- 

 ica except in the region west of the Rocky Mountains. 



2. SPIRiEA, L. Meadow-Sweet. 



Petals 5, rounded, nearly sessile. Stamens numerous. Carpels usually 

 5 or more. — Perennial herbs or mostly shrubs: flowers white or rose-c(dorod, 

 in compound corymbs or spikes. — We follow the arrangement of Dr. Maxi- 

 mowicz in recognizing the four following genera as distinct from Sju'raa. 

 Bot. Calif, ii. 443. 

 ♦ Erect .shrubs : petals rose-colored or purplish : flowers in compound corymbs. 



1. S. betulifolia, Pallas. Glabrous or finely pubescent, with rc<ldisl> 

 bark: leaves broadly ovate to ovate-oblong, acutely and unequally .«orr:ife or 

 incised, on short petioles or nearly se.ssile : flowers pale purple, the fiustigiato 

 corymbs often Icafy-bracted : ovules 5 to 8. — ^S^. corymlmsn, Raf. Head- 

 waters of the Missouri, eastward in the Alleghany Mountains, wcslwanl to 

 N. California, and northward to Alaska. 



Var. rosea, dray. C(jrolla rose-red. — Proc. Am Acad. viii. 3Sl. W. 

 Wyoming, Maho, and westward to Oregon and California. 

 » « Low herbaceous jxrennials, woody at base: petals ivhite : flowers in dense 

 cylindrical spikes on scape-like stems. 



2. S. CSespitOSa, Nutt Cespitose, on rocks: leaves rosulatc on the short 

 tufted branches of the woody spreading rootstock, oblanceolato or linf.ir- 



