Plant a,ii~ 

 fls. poll/ 



I THE SECTIONS. 



fjs. in simple or panii-Ied 

 .,:.H.,lI,i 3-seeded. (Bo- 



nielies 

 :i(_s No 



cort/mbs or panicles: 

 seals several. 

 Inflorescence a simple umbel-like raceme: 



Section 5. Spiearia (Species No 



Section 1. Petrophytum (Species not in cult. ). 



This section contains a few ratlier rare American spe- 

 cies of wliich none is in cultivation. The best known 

 is S. csespitasa, Xiitt. (ritr-plii/fnm cerspitdsum, 

 Rydb.), a dwarf ■■• i it.. . ,il. In.il., milv n f.v,- uirhes 



high, with crow.lr,' ,., .i ,.,;., - ., , n .. iiitish 



fls. in dense, UMi:. i -lalks 



arising from tlir ii.i i ; ,. ^ ; ., , i, l : i. . . ■.■.■. It 

 is very unlike aiij iiib. i >iiir. u lui.l iii-ji.j r. -mhIiIvs in 

 habit a Saxifraga. It is pfrliMjis hctft-r n-.ir.l.d as a 

 distinct genus like the allied Kdseya unifldrn, Rydb. 

 (Briogynia unifldra, Wats.), and Eriogynia pectinata. 

 Hook. 



Section 2. Sibir;ea (Species No. 1). 



1. laevigata, Linn. {S. AlttVica, Pall. Hibirwa Icevi- 

 gdta, Maxim,). Shrub, .■> ft. high, with stout upright 

 branches : Ivs. cuneate-oblong, bluish green, glabrous, 

 1K-3K in, long: fls, polygamous, greenish white in 

 terminal panicles, 3-5 in. long, those of the staminate 

 plant somewhat showier. May. Siberia. — Hardy. 



SPIR^A 

 Section 3. CHAiLfflDRYON (Species ) 

 &. Ji'ls. in sessile umbels, with none 

 or very small Ivs. at the base or 

 only the lower umbels on leafy 

 stalks. 

 B. Foliage entire or crenately den- 

 tate only near the apex, often 



S-nerved, grayish green 2. 



BB. Foliage dentate or serrate, usu- 

 ally penninerved, b^'ight 

 green. 

 c. Shape of Ivs. linear-lanceo- 

 late: glabrous :i. 



CC. Shape of Ivs. ovate to oblong- 

 lanceolate : finely pubes- 

 cent when young. 

 D. Umbels on the lower part 

 of the branches stalked. 



E. lyvs. oblong 4. 



EE. Lvs. obovate ,"i. 



i«i>. Umbels all sessile, SS-fld. ij. 

 \. Fls. in ambel-like racemes on 

 leaf,/ stalks. 

 B. Margin of lvs. entire or crenate 

 or dentate only toward the 



o. Foliage grayish pubescent 



on both sides 7. cana 



cc. Foliage almost glabrous. 

 D. Shape of Ivs. elliptic to 

 oblong-lanceolate. 

 E. Lvs. penninerved: 



shoots angular 8. alpina 



EE. Jyvs. all or partly 

 S-nerved. 

 F. Shoots striped: lvs. 



all S-nerved II. crenata 



FF. Shoots terete: lvs. 

 partly penninerved , 



partly S-nerved HI. Pikowiensis 



Dl). .Shape of lvs. almost or- 



hiriilar. ■'.,-/ ill. br<iail..\l. bracteata 

 BE. Maniiii III Irx. iiirisi'Ifi sirriite 



arguta 



multiilora 



prunifolia 



.V... ]:i 



DIJ. Shoot. 



.glabrous. 'in. chamaedryfolia 



2. hypericifdlia, Linn. Vigorous sbnih, r. ft. Iii-li, 

 with slender arching or upriu-lit Lrjiiu'lir-i : lvs. ;ihiM.st 



sessile, cuneate-obovate to <.Im.\ :.n I i nlni , . :; i,, t \ r.l 



or with few lateral veins. :i\" ' i , ' in- 



long; fls. small, white, in sr^ II- 



ally pubescent; petals almost ,.i i-i, iil:ii , n-inM. l-nL-.r 

 than stamens. April, May. S. E. En. to Siberia. - Va- 

 riable species. Var. acutifdlia, Wenzig {S. acutifolia, 

 Willd. S. hypericifdlia, var. aciita, Ser.). Lvs. nar- 



