138 ON SOUTH-AMEEICAN APOCTNACEiE. 



Ehodocaltx. 



Tliis genus comprises several low-growing plants, for the most part springing out of 

 ligneous tuberose rhizomes, producing several short stems, knotty and bracteolate at the 

 base, bare and erect above, where they are furnished with few opposite broadish leaves, 

 either subsessUe or petiolate. The inflorescence consists of one or few flowers, axUlary 

 or terminal in the sinus of the two ultimate leaves ; these are supported by slender pedi- 

 cels, bracteolate at the base ; the sepals are rather large, often of a reddish hue, sub- 

 membranaceous, retioulately veined, acute, sometimes subcordate at the base, with an 

 inner, broad, deeply lacinulate scale; the corolla is salver-shaped; tube narrowed at 

 the base for the length of the calyx, funnel-shaped above ; segments oblong, one-third 

 of its length, with dextrorse convolution ; stamens seated in the constriction of the tube ; 

 anthers linear, acute, subcohering, with 2 short basal prongs ; style filiform ; clavuncle 

 thickened, cylindrical, with a basal peltiform appendage. But the chief peculiarity is 

 the manner in which its seeds are suspended from the lamellar placentae of 2 terete 

 follicles; these are imbricate, oblong, subcompressed, dorsally convex and cancellately 

 reticulated, concave on the ventral face, where they are marked with a raphe running 

 from top to bottom, which at its summit is extended into a filiform funicle 6 times 

 the length of the seed, and by which the latter is suspended from the placenta ; the 

 seed is. crowned by an erect coma 5 times its length; the anatropous embryo is im- 

 bedded in albumen, its 2 oblong foliaceous cotyledons, laterally incurved, are 3 times 

 as long as the more slender terete superior radicle. 



The presence of a distinct funicle, by which the seed is suspended, brings this genus 

 into proximity with Stipecoma ; but it wants the long peculiar rostrum, seen in the seed 

 of the latter genus ; in other respects it is extremely different. 



1. RnoDocALyx rotundipohus, Miill. Fl. Bras. xxvi. p. 173, tab. 51. In Brasilise prov. central. : v. s. 

 in herb, meo, Minas Geraes (Claussen) . 



This plant, in the herbarium, may at first sight be mistaken for the Dipladenia illus- 

 tris, var. rotundifoUa, of Miiller ; but it may be recognized by the presence of its lower 

 bracteiform leaves, by its smaller flowers, larger (not lanceolate) sepals, a shorter tube 

 of the corolla, which is a little longer than the sepals. It has been wrongly regarded as 

 identical with the Echites erecta of Velloz (which is Laseguea erecta, MiiU.). Its ligneous 

 rhizome is horizontal, sending from one extremity several short erect stems, scarcely a 

 foot long, bearing towards the base a few opposite acute bracteiform scales (abortive 

 leaves), and, above the middle, 2 or 3 pairs of leaves about 2 in. apart ; the leaves are 

 suborbicular, with a very short acumen, pale green above, thickly clothed with a whitish 

 tomentum, with about 4 pairs of distant immersed nerves. If— 2f in. long, lj-2| in. 

 broad, with a pubescent petiole 1 line long. The inflorescence is tomentous, 2-4| in. 

 long, on a straight peduncle bearing about 4 pairs of opposite flowers (sometimes 

 reduced to a single one) on pedicels 10 lines long, each furnished at the base with a bract 

 nearly of its length, acutely oblong, glabrous, with ciliated margins; sepals oblong, 



