ON SOUTH-AMEEICAN APOCYNACE^. 



263 



Species exclusse : — 



J3". suberectum, G. Don, Diet. iv. p. 83 . 



H. grandifiorvm, A. DO. Prodr. viii. p. 426 



.H". circinalis, G. Don, Diet! iv. p. 83 



S. molle, A. DC. I. c. p. 427 . . . 



S. parviflorum, Benth. PI. Hartw. 



S. megalagrion, Miill. PL Bras. xxvi. p. 170 



S. Beidelii, Miill. I. c. p. 170 . . 



B.. cmmilare, A. DC. I. c. p. 428 



H. glmidulosv/m, A. DC. I. c. p. 427 



jS". glabratum, A. DC. I. c. p. 427 . 



S. Mexicana, A. DC. I. c. p. 428 . 



II. suberectum, G. Don, Diet. iv. p. 83 



= Qhariomma swrrecta. 

 Odontadenia grandiflora. 

 Anechites circinalis. 

 Prestonia mollis. 

 Temnadenia parviflora. 

 Prestonia megalagrion. 

 Temnadenia Meidelii. 

 Tem/nadenia annularis. 

 ^chiles glandulosa. 

 Prestonia glabrata, H. B. K. 

 Mitozus Mexicanus. 

 Urechites suberecta. 



Cycladenia. 



This interesting genus was established about 1850 by Mr. Bentham in his ' Plantse 

 Hartwegianae ' (no. 1834), upon a solitary species from California. Its stems, probably 

 herbaceous, only a few inches high, rise out of a perennial thickish rhizome, as in 

 Somaladenia ; the ovate very obtuse leaves, less than 1 in. long, are smooth and fleshy ; 

 the inflorescence axillary and laxly racemose, the peduncle bears about 6 flowers on brac- 

 teolate pedicels 6 lines long ; sepals unequal, narrow, 3 lines long, without internal scales ; 

 corolla hypocrateriform, resembling that of Vinca rosea, of a purplish colour, campa- 

 nulate in the upper part of the tube, which is furnished within, at the middle, with a 

 pilose ring, and 5 distinct scales placed above the insertion of the stamens, as in Scema- 

 dictyon, the mouth being quite bare ; the segments broad, gibbously ovate, are half the 

 length of the tube, with a sinistrorse convolution ; the included stamens have very short 

 filaments ; the anthers cohering in a cone by their agglutination to the clavuncle, are 

 very acuminate above and biaristate at the base ; the disk annular, entire, shorter than 

 the 2 free ovaries, which have amphitropous ovules ; style simple ; clavuncle incrassate, 

 with a broad peltate basal membrane ; stigmata small and terminal ; fruit unknown. 



C. humilis is a very pretty glabrous plant which I have. not seen, has the habit of 

 Villarsia pwmila, and has no affinity with Vinca, as its stamens show. The form of the 

 corolla, the presence of suprastaminal appendages, and the structure of the stamens, 

 indicate its affinity towards Hcemadictyon. 



The Cycladenia JSarrisonii, Lem., is Odontadenia Harrisii {supra, p. 128). 



IIeterotheix. 



A genus established by Miiller in 1860, upon a single Brazilian species, well figured 

 and described by him. It was repudiated by Bentham and Hooker in the ' Genera 

 Plantarum,' ii. p. 724, who referred it to JEcUtes, a genus, in their estimation, consisting 

 of a very heterogeneous group of plants ; but it cannot be reconciled with that genus 



