JOHNSON: A REVISION OF THE SECTION BORAPHILA $7 



formed a continuous specific line. S. leucanthemifolia occupies a narrow 

 belt of the higher Appalachians, from Maryland to northeastern Georgia. 

 Only a single American specimen of what is probably Saxifraga stella/ris 

 L. has been available for study — a specimen from Labrador. None of the 

 western plants examined can be referred to this species, although a specimen 

 from Mt. Hood, Oregon, mentioned later, bears a strong resemblance to it 

 in some vegetative characters (Plates II, XIX). 



When Haworth (14) in 1821 divided the old Linnean genus Saxifraga 

 he brought together the species S. leucanthemifolia Michx., S. Clusii Gouan, 

 and S. stellaris L. under the new genus Spatularia. Haworth clearly diag- 

 nosed the characters which define the group. He further divided the genus 

 into two divisions, viz., Verae Rectirostratae, including S. leucanthemi- 

 folia and S. Clusii; and Spuriae: Curvirostratae, including S. stellaris. 

 The material available is inadequate to verify this distinction. Tausch 

 and his followers include these species in the section Arabidia, but Seringe 

 (26) erroneously included S. arguta D. Don. Ledebour (18) failed to, 

 recognize the distinction made by these writers when he combined the sec- 

 tions Arabidia and Micranthes, as did also Engler (4) in creating the sec- 

 tion Boraphila. Small (27) was the first to recognize the interpretation put 

 upon this group by Haworth, when he adopted that author's genus Spatu- 

 laria. 



Section Arabisa 



Key to the Species 



I. Leaves dentate 



A. Leaves deeply and coarsely dentate; inflorescence loose 5". leucanthemifolia 



B. Leaves more shallowly dentate, mostly towards apex 



a. Inflorescence commonly diffuse; some or most of flowers often replaced by 

 bulbils S. ferruginea 



b. Inflorescence reduced 



\. Flowers, except the terminal, replaced by bulbils ; scapes erect, rigid, 

 glabrous ; branches of inflorescence short and mostly at right angles with 



stem S. foliolosa 



2. Not bulbil-bearing, flowers conspicuous ; scapes pubescent or 



glabrous S. slellaris"' 



II. Leaves entire, small, lanceolate 5". bryophora 



Saxifraga bryophora A. Gray, Proc. Am. Acad. 6 :533. 1865. 



Saxifraga leucanthemifolia Michx. var. integrifolia Engler, Monogr. 

 Saxifr. 135. 1872. 



Spatularia bryphora (A. Gray) Small, N. Am. Fl. 22:2:148. 1905. 

 (Plate XIX). 



^" The detailed treatment of this species is deferred for a future paper. 



