Nov., 1923] RYDBERG — NORTH AMERICAN FABACEAE 



491 



Balboa Liebm. Vidensk. Meddel. 1853: 106. 1854. Type: Balboa 



diversifolia Liebm., the only species. 

 Seemannantha Alef. Bonplandia 10: 264. 1862. This was a substitute 



for Macronyx, and hence based on the same type. 



Cracca is a large genus, probably containing about 150 species, found 

 in warmer regions of both hemispheres. In North America (including 

 Central America and the West Indies), there are 72 species, of which 65 are 

 native and 7 introduced. 



Taubert divided the genus into 4 sections: Brissonia, Reineria, Pogo- 

 nostigma, and Requienia. Of these the last two, which are not represented 

 in America, should be removed as distinct genera, having 1 -seeded fruits. 



The principal character by which Taubert distinguished the first two 

 sections was the relative width and length of the calyx lobes. Some species, 

 as for instance C. lencantlia, which has long and narrow calyx-lobes, really 

 belong to Brissonia instead of Reineria. A better distinction is the in- 

 florescence, which is monopodial in the former and sympodial in the latter. 

 In the monopodial inflorescence the terminal raceme is best developed, but 

 many of the species bear also secondary racemes in the upper axils. In 

 the sympodial inflorescence the terminal raceme develops first, but in the 

 uppermost leaf-axils a branch is produced which in its turn develops a 

 terminal raceme; this is repeated several times, and the racemes therefore 

 appear to be opposite the leaves. In a few species, as for instance C. 

 rhodantha, C. foliosa, C. vicioides, and C. Brandegei, the racemes are mostly 

 at the nodes, but neither opposite the leaves nor strictly axillary; they are 

 inserted in the axils but obliquely, i.e., not in the plane determined by the 

 stem and the rachis of the leaves. The monopodial or sympodial character 

 is not perfectly clear. 



Several of the species are used as a fish-poison by the natives of the 

 region where they grow, others for poisoning arrows in Southern Africa; 

 still others furnish a blue dye, somewhat resembling indigo. 



3. Peteria A. Gray. PI. Wright 1 : 50. 1852 



Perennial herbs, somewhat woody at the base. The leaves are odd- 

 pinnate with spiny stipules. The flowers are usually in terminal racemes. 

 The calyx is cylindro-campanulate, gibbous at the base above; 5-lobed with 

 the upper two lobes united high up. The corolla is ochroleucous or nearly 

 white, the banner long-clawed with an oblong-obovate blade; the wings 

 have an obliquely oblong blade, slightly auricled at the base, and a slender 

 claw; the blades of the keel-petals are obliquely obovate, obtuse, with a 

 broad, rounded basal auricle. The stamens are diadelphous, with the upper 

 filament wholly free. The ovary is short-stipitate or sessile, many-ovuled, 

 the style with a horny base, inflexed. glabrous, except at the apex, where 

 there is a ring of hairs. The pod is linear, straight, compressed, 2-valved, 

 many-seeded, with thick sutures. 



The genus was based on a single species, P. scoparia A. Gray, and con- 



