ON SOUTH-AMERICAN APOCYNACEZ. 149 
14. PnEsTONIA LATA, nob. : scandens, ramulis teretibus, fistulosis, pallidis, striolatis, hirsutulis cum pilis 
imo tuberculatis ; axillis remotis, ad lineam transversam stipulis plurimis subsetaceis munitis: foliis 
ovalibus, imo rotundatis, vix cordatis, apice in acumen acutum subito constrictis, submembranaceis, 
marginibus ciliatis vix revolutis, supra viridibus, subnitentibus, in costa sulcatis, nervis prominulis 
venisque transversum reticulatis fusco-rufescentibus, et parcissime pilosis, subtus lete flavis, opacis, 
glabris, sed costa nervis venisque rufo-tomentellis ; petiolis brevibus, rufo-puberulis : corymbo laterali, 
quam folium 3plo breviore; pedunculo valido, dense pubescente, imo stipellis involucellato, apice 
2-ramoso, ramulis congestim plurifloris; pedicellis calyce paullo longioribus, bracteola 1 breviore 
suffultis; sepalis majusculis, oblongis, subito cuspidatis, membranaceis, viridulis, extus parce pilosis, 
undulatis, intus squama lata tridenticulata munitis; corolla glabre tubo validiuscule cylindrico, fauce 
annulo integro, et subtus appendicibus 5 lanceolatis apice exsertis instructo; segmentis rhomboideo- 
ovatis, angulo sinistro acutis, tubo brevioribus; staminibus ex lineis 5 pilosis medio tubi inser- 
tis; antheris acuminatis, imo biaristatis; disco urceolato, carnoso, apice breviter 5-lobo, ovario 
longiore; stylo tenui; clavuncula incrassata, oblonga, 5-glandulosa, imo membrana peltata in- 
structa ; stigmate terminali, brevi, oblonge bilobo. In Brasilia: v. v. et s. in herb. meo Rio de Janeiro, 
Monte Corcovado. á 
A species with its fistulous branches 2 lines thick, having stipuliferous axils 8 in, apart ; 
leaves 4-5 in. long, 23-34 in. broad, on petioles 2 lines long; peduncle of corymb 9 lines 
long, its branches 3 lines long; pedicels rather stout, 4-6 lines long; sepals 6 lines long, 
3 lines broad; tube of corolla 7 lines long, 2 lines broad; segments 4 lines long, 3 lines 
broad ; filaments 1 line long; anthers 24 lines long. 
15. PRESTONIA MEGALAGRION, nob.: Hemadictyon megalagrion, Müll. I. c. p. 170: Echites megagros, Vell. 
Fl. Flum. p. 110, Icon. iii. tab. 33. In Brasilia, prov. Rio de Janeiro, Campo Grande (Velloz) : 
v. s. in herb. Mus. Brit. Itagoahy (Bowie and Cunningham). 
A handsome species, agreeing in habit and inflorescence with Prestonia. Its scandent 
branches are subtomentous, lactescent, with axils 5-6 in. apart, furnished with stipules ; 
leaves opposite, patent or reflected, broadly ovate-oblong, roundish at the base, shortly 
acuminate and mucronate at the apex, subplicate, crenulate, and ciliate on the 
margins, fuscous green above, obsoletely pilose, sulcate along the arching divaricated 
nerves, yellow hispidulous along the slender immersed midrib, beneath ferruginously 
 Opake, patently hispid on the midrib and prominent nerves, 63-73 in. long, 2343 in. 
broad, on stout hispid petioles 3—4 lines long; corymb solitary and lateral at each node, 
hispidly pilose, on a stout reflected peduncle 9 lines long, rising out of a stipuloid 
involucel, shortly 3-4-branched at the apex, and bearing numerous flowers aggregated 
in a head 2 in. in diameter; pedicels densely tomentous, recurved, 4 lines long, sup- 
ported by linear hispid bracteoles 13 line long; sepals oblong, acuminate, pilose on both 
sides, 7 lines long, 2 lines broad, each with an inner broadly ovate truncated scale denti- 
culate at the apex; tube of corolla yellowish, pruinosely pubescent, 8 lines long, its 
mouth with an annular ring, and beneath it 5 subulate subexserted appendages ; seg- 
ments inequilaterally oblong, acute, 6 lines long; stamens as in the preceding species ; 
disk urceolate, submembranaceous, with an emarginately 5-lobed margin, longer than the 
included 2-lobed ovary. 
