MACLOSKIE I POLYGONACE/E. 347 



scarious bracts. Perianth 3-parted, its dobes erect, obtuse, oval or longer. 

 Anthers 3. Stigmas 2, sessile, nearly globose. Seeds trigonal (Fig. 62). 

 S. Fuegia, by Rio Azopardo. (Dusen.) Lower and more densely 

 branching than K. islandica. 



2. ERIOGONUM Michx. 



Stemless or leafy-stemmed herbs without ochreae. Flowers small, in 

 cymes, umbels or heads, subtended by involucres. Calyx 6-cleft or 6- 

 partite. Stamens 9. Style 3-parted ; stigma capitate. Acliene 3-angled. 



Species 160, chiefly in the Western United States. 



E. AMEGHINOI Speg. 



Cnrvembryitm. Low, leafy annual ; the radical leaves orbiculate, basally 

 rounded or subcordate, long-petioled ; the cauline elliptical or obovate, 

 basally cuneate, short-petioled ; when young somewhat villous, afterwards 

 glabrate. Peduncles numerous, at first scapiform, afterwards 5-6-times 

 dichotomizing, pubescent. Involucre sessile, campanulate, 5-lobed. 

 Perigonium more or less pediceled, exsert; the segments narrow, 

 acutish, pubescent, yellowish inside. 



S. Patagon., in dry places between S. Julian and Rio Deseado, and 

 near Lago Colu-huapi. Differs from R. rotundifolium Benth., by the 

 sessile involucres, and narrower perigonial segments. 



3. RUMEX Linn. Sorrel. 



Stems leafy, grooved, with cylindrical sheathing stipules and paniculate 

 flowers. Calyx, 2-seriate, each series 3-leaved ; the inner 3 becoming 

 wings in fruit, one or all having a basal tubercle. Stamens 6, short. 

 Style 3-parted ; stigmas tufted. Achenes trigonal. 



Species 130, widespread in nontropical regions. Several in Chili and 

 Argentina. Few in Brazil, Austral., or N. Zeal., i in Tristan; some in 

 S. Afr. 



KEY TO THE SPECIES. 



A. Dioecious or polygamous ; leaves more or less hastate (except 3.) 



b. Basal leaves stalked, upper sessile. Fruiting calyx enlarged. acetosa. 



b2. Leaves all stalked. Fruiting calyx not enlarged. Rootstalk creeping. 



acetosella. 

 3. Leaves rosulate, wavy, lanceolate. Stems short. hippiatricus. 



