Di" Balfour's Description of Bare Plants. 203 



wirj, about li inch long, 2-3 flowered (rarely 1 flowered), with a 

 small triangular hractlet at the base of the pedicels or partial flower- 

 stalks, which are about quarter of an inch long, and thickened 

 upwards. On making a section of the pedicel near its upper 

 part, the cellular tissue in the centre was found to be arranged 

 in a stellate manner. Inflorescence definite, expansion of flowers 

 centrifugal. Calyx glabrous, of five somewhat elliptical, obtuse, 

 concave, adpressed sepals, membranous at their margins, the 

 two outer ones smaller. Corolla shining, glabrous, between fun- 

 nel-shaped and salver- shaped, of a fine purplish red colour ; tube 

 slightly contracted at its junction with the limb, then widening 

 and ultimately tapering downwards, about 2 inches long, four 

 times longer than the sepals, purplish-red outside, and of a 

 whitish colour within ; limb expanded, slightly revolute at the 

 margin, 2h inches across, plaited or undulated, of five blunt 

 slightly notched lobes and shallow sinuosities between them, the 

 union of the jjetals marked by two lines, prominent on the lower 

 side, uniting at the margin of the limb, and enclosing a triangu- 

 lar space ; spiral vessels distributed through the substance of the 

 corolla. ^Estivation contorted. Stamens 5, colourless, exserted 

 beyond the tube and towards one side of the throat, shorter than 

 the limb ; filaments unequal in length, from 2 to 2-J- inches long, 

 inserted near the base of the tube of the corolla, flattened 

 at their union with the corolla, tapering towards their an- 

 therine extremity, with scattered hairs and tooth-like pro- 

 jections towards their lower half ; anthers 2-lobed, opening by 

 longitudinal dehiscence, innate, introrse ; pollen sjjherical, extine 

 marked with numerous prominent processes. Pistil rather longer 

 than the longest stamens ; stigma colourless, 2-lobed, capitate, 

 tubercular, i. e. covered with numerous projecting cellular pro- 

 cesses ; style about 3 inches long, slender, tapering ; ovary supe- 

 rior, conical, gradually ending in the stigma, surrounded at its 

 base by a thickened annular disk of a yellowish colour ; 2-celled, 

 with two ovules in each cell ; ovules somewhat trigonous, ana- 

 tropal. 



The plant evidently belongs to the genus Exogonium of Choisy, as 

 defined in De Cundolle's Prodromus, although the author places 

 it under the genus Ipomrea, from which the exserted stamens at 

 once distinguish it. The following are the definitions of the 

 allied genera, as given by Choisy : — 



A — Ovary 3-4-celled, each cell having 2 ovules. 



1. Pharhitis. 



B — Ovary 2-celled, each cell having 2 ovules. 



2. Convolvulus, stigmata linear, cylindrical, stamens included. 



