26 NORTH AMERICAN FLORA [Volume 25 



Sepals 4-7 mm. long ; petals 9-16 mm. long, narrowly obovate. 



Styles glabrous or nearly so ; sepals finely and thinly pubescent. 1. 0. Acetosella. 



Styles densely pubescent ; sepals coarsely and densely pubescent. 2. O. oregana. 



Sepals s-10 mm. long ; petals 23-30 mm. long, broadly obovate. 3. O. macra. 



1. Oxalis Acetosella L,. Sp. PI. 433. 1753. 



Oxalis longiflora L. Sp. PI. 433. 1753. 



Oxalis americana Bigel.; DC. Prodr. 1 : 700. 1824. 



Plants 3-10 cm. tall, with slender rootstocks ; leaves erect or ascending, the petioles 

 slender, sparingly villous, the leaflets 1.5-2.5 cm. broad, with scattered hairs on both sides; 

 cleistogamous flowers nodding, the peduncles shorter than the petioles ; petaliferous flowers 

 erect, the peduncles longer than the petioles ; sepals of the petaliferous flowers oblong to 

 oblong-lanceolate, 4-5 mm. long, ciliate; petals 10-16 mm. long, white or pink and striped 

 with deep-pink or purple especially near the base ; gynoecium glabrous or nearly so ; cap- 

 sules of the petaliferous flowers ovoid-globose, 3-4 mm. long, those of the cleistogamous 

 flowers shorter and broader. 



Type locality : Europe. 



Distribution : Nova Scotia to Manitoba, and southward on or near the mountains to North 

 Carolina and Tennessee. Also in Europe and Asia. 



Illustrations: Fl. Dan. pi. 980; Woodv. Med. Bot. 3: pi. 201 ; Engl. Bot. pi. 762 ; Baxter, 

 Brit. Bot. pi. 327 ; Svensk Bot. 1: pi. 10; Schkuhr, Handb. pi. 123 ; Karst. Deuts. FI. pi. 359 ; 

 Britt. & Brown, 111. Fl. f. 2250. 



2. Oxalis oregana Nutt. ; T. & G. Fl. N. Am. 1 : 211. 1838. 



Oralis Acetosella oregana Trel. Mem. Bost. Soc. Nat. Hist. 4 : 90. 1888. 

 Crri oregana Greene, Man. Bay Reg. 71. 1894. 



Plants 5-16 cm. tall, with rather stout rootstocks, pubescent in most of its parts in 

 about the same degree as O. Acetosella ; leaves ascending or spreading, the petioles stout- 

 ish, variable in length, the leaflets 2-3.5 cm. broad, ciliate, but often otherwise glabrous; 

 cleistogamous flowers nodding on very short peduncles ; petaliferous flowers erect on 

 villous peduncles which are usually shorter than the petioles ; sepals of the petaliferous 

 flowers broadly oblong, 6-7 mm. long at maturity, coarsely pubescent and ciliate ; petals 

 pale-pink, 9-18 mm. long; gynoecium usually copiously pubescent; capsules of the petal- 

 iferous flowers globose-ovoid, 7-S mm. long, those of the cleistogamous flowers smaller. 



Type locality : Shady woods of the Oregon. 

 Distribution : Washington to California. 



3. Oxalis macra Small, sp. nov. 

 Plants 9-28 cm. tall, conspicuously more pubescent than those of O. Acetosella. with 

 stout rootstocks ; leaves erect or ascending, the petioles very stout, villous, sometimes 

 copiously so, the leaflets 3-5 cm. broad, or sometimes narrower, ciliate and quite copiously 

 pubescent beneath, sparingly pubescent or glabrous above ; cleistogamous flowers nodding, 

 the copiously villous peduncles much shorter than the petioles ; petaliferous flowers erect, 

 the sparingly villous peduncles as long as the petioles or longer ; sepals of the petaliferous 

 flowers broadly oblong, 8-10 mm. long at maturity, densely pubescent and ciliate ; petals 

 23-30 mm. long, deep-pink ; gynoecium sparingly pubescent, especially about the top of the 

 ovary and the lower part of the styles ; capsules not seen. 



Type collected in the Santa Lucia Mountains, Monterey County, California, February, 1898, 

 R. A '. Plaskett. 



Distribution : Oregon and California. 



2. HESPEROXALIS Small, gen. nov. 

 Acaulesceut herbs with elongate scaly rootstocks. Leaves approximate near the apex 

 of the rootstock or on a branch of it, with long petioles and almost palmately 3-foliolate 

 blades, the lateral leaflets scarcely inequilateral. Petaliferous flowers borne in a terminal 

 umbel-like cyme which is subtended by a whorl of narrow bracts. Cleistogamous flowers 

 wanting. Sepals 5, very thin, the inner and outer ones nearly equal. Corolla funnel- 

 form. Petals 5, broadened upward, notched at the apex. Stamens 10, united at the base 

 into a tube which is nearly as long as the shorter filaments. Ovary elongate, each carpel 



