cent] 



&1>z &xck$\ix\) at 25atann. 



248 



filiform curved caudicies which adhere to 

 a common gland. 



CENTROPOGOK A genus of Lobeliacece, 

 consisting of undershrubs with irregular 

 flowers on long axillary stalks. The five 

 stamens are united into a tube, and spring 

 from between the corolla, and a ring-like 

 fleshy five-lobed disc, surrounding the 

 inferior two-celled ovary. The two lower 

 anthers are terminated by an ovate tri- 

 angular cartilaginous point. The plants 

 are natives of tropical America. [M.T.M.] 



CENTROSEMA. A genus of prostrate 

 or twining perennial plants belonging to 

 the Leguminosce, and distinguished from 

 its nearest allies by its having on the back 

 and near the base of the standard a short 

 spur, from which circumstance the genus 

 receives its name. The species are almost 

 entirely American, and the greater number 

 are found in Brazil. The leaves are made 

 up of three leaflets, rarely of Ave or seven, 

 the leaflets opposite and the terminal one 

 rather distant,; in two species they are 

 digitately arranged and from three to five 

 in number, while in a few others but one 

 leaflet is present. The large and elegant 

 pea-like flowers are single or in axillary 

 racemes, and white violet rose or blue in 

 colour. The pods are very narrow, com- 

 pressed, thickened at both sides, and ter- 

 minating in a long point ; in some of the 

 species they are eight inches long. The 

 leaves of G. macrocarpum are eaten in 

 Guiana. C. virginianum is found in Brazil 

 and "West Africa, as well as in the United 

 States. Upwards of twenty species are 

 known. [A. A. B.] 



CENTROSIS. Corymbis. 



CENTROSOLENIA. A genus of Gesne- 

 racece from British Guiana, founded on a 

 single plant, which has a short creeping 

 stem, subcordate petiolate leaves, and soli- 

 tary axillary peduncles, sometimes bearing 

 many pedicels. The calyx is five-parted 

 with serrate segments ; the tube of the 

 corolla has a spur at its base, and the limb 

 is slightly expanded into five small broad 

 lobes. The four included didynameus 

 stamens, with the rudimentary fifth, are 

 inserted in the base of the tube. The 

 ovary is oblong-conical and hairy. This 

 genus is evidently allied to Nematanthus, 

 but the spur of the flower, coupled with 

 the habit and the toothed segments of the 

 calyx, distinguish it. [W. C] 



CENTROSPERMUM. The name some- 

 times given to an annual cornfield "weed of 

 Spain and Algeria, very near to the genus 

 Clirysanthemum, and very like our own 

 corn-marigold, Chrysanthemum segetum, 

 The achenes in the last-named plant are 

 naked at top, but in this, Ch. viscosum, 

 I those of the ray florets have a pappus of 

 I three, and those of the disc of one awn, 

 while the stems are smooth and not 

 clammy. [A. A. B.] 



CENTROSTEMMA. A genus of Asclejna- 

 dacew, containing five species, natives of 



the Indian Archipelago, the Moluccas, and 

 the Philippine Islands. They are twining 

 shrubs, with opposite coriaceous leaves, 

 and umbels on interpetiolar and terminal 

 peduncles, composed of many large yellow- 

 ish flowers. The calyx is five-parted. The 

 limb of the corolla is deeply five-cleft and 

 reflexed ; a hairy ring exists in the throat 

 of the corolla around the base of the 

 gynostegium, which is exserted. The sta- 

 minal corona consists of five fleshy leaves 

 inserted on the summit of the gynostegium 

 and surpassing the stigma. The anthers 

 are surrounded by a spreading membrane 

 which attaches them to the stigma ; the 

 pollen masses being oblong, with a pellucid 

 interior margin, and attached by short 

 processes. The pentagonal stigma is 

 lengthened out into a cone. The follicles 

 are solitary, long and cylindrical, and con- 

 tain numerous comose seeds. The hairy 

 ring in the throat of the corolla separates 

 this genus from Uoya, to which otherwise j 

 it is very nearly related. C. multiflorum is | 

 a well-known handsome hothouse shrub, 

 often called Cyrtoceras reflexum. [W, C] 



CENTUNCULUS. Bastard Pimpernel. 

 A minute herbaceous plant belonging to 

 the Primulacece, and closely allied to Anagul- 

 lis, from which it may at once be distin- 

 guished by its four-parted flowers and four 

 stamens, which are glabrous. The whole 

 plant consists of a small fibrous root, a 

 simple or slightly-branched stem, which 

 rarely exceeds an inch and ahalf in height, 

 from a dozen to twenty, or less, ovate- 

 pointed sessile leaves, and a few solitary 

 sessile flowers of a pinkish hue and of 

 very short duration. The seed-vessels 

 resemble those of pimpernel, for a starved 

 specimen of which the plant might be 

 mistaken. It grows in many parts of Great 

 Britain in sandy or gravelly places, espe- 

 cially where water has stood during the 

 winter, and not unfrequently in company 

 with another minute plant, Badiola Mille- 

 grana. French, Centenille bassette; Ger- 

 man, Centunkel. [0. A. J.] 



CEPHAELIS. The plant producing the 

 true Ipecacuanha belongs to this genus 

 of Cinchonacece, which is characterised ] 

 by its flowers being collected together In 

 heads surrounded by a leafy involucre; 

 the limb of the calyx very small and five- 

 toothed; the corolla funnel-shaped with 

 five small lobes ; the anthers inclosed 

 within the corolla ; and the fruit succulent 

 with two compartments, each containing a 

 single seed, striated on the outer side. 

 The Ipecacuanha plant is a native of 

 Brazil. Its root, the part used in medicine, 

 is flexuose but little branched, and the 

 rind is marked by a number of circular 

 projecting knots or rings which are very 

 characteristic. The stem is creeping and 

 herbaceous, with oblong obovate leaves 

 and drooping heads of flowers. The emetic 

 properties of the root are due to a 

 chemical principle called emetin. 



Ipecacuanha is largely employed in medi- 

 cine as a safe emetic, and in smaller 



