ments ; styles cleft in two. Steudel de- 

 scribes thirteen species, which are all Ame- 

 rican. [D. 31.] 



PSIL08. In Greek compounds = thin. 



PSILOTOI. A genus of clubmosses 



with a three-sided stem, three-celled axil- 



! lary capsules, and small bristle-pointed 



; leaves. The stem is erect and dichotomous. 



1 The only species, P. triquetrum, grows on 



; the trunks of trees in tropical or equable 



climates, and extends through Brazil and 



Central America to the Southern United 



States. It bears cultivation well, and is 



not uncommon in hothouses. The spores 



burst when placed in water, and emit a 



cloud of microscopic particles. [31. J. BJ 



i PSILURrs. A genus of grasses belong- 

 ing to the tribe Rottboellece, The inflores- 

 cence is in rounded slender spikes ; spike- 



: lets two-flowered, the lowest flower sessile 

 and hermaphrodite, the upper stalked and 



; minute; glume one, very small, oval, and 

 membranous ; pales two, membranaceous, 

 the lowest one-nerved with a short awn 

 at the point, the upper a little longer, and 



i two-keeled; stamen one; stigmas two. Only 



! one species is described, P. nardoides, 

 which is an annual grass, native of the 



; south of Europe. [D. 31.] 



j PSOPHOCARPUS. A genus of Legumi- 

 vosce, founded upon an East Indian and 

 Mauritius plant previously referred to 

 : DoKchos, and two others from Western 

 | Africa have since been added to it. They 

 ' are tuberous-rooted herbs, with herbaceous 

 twining stems, trifoliate leaves, and ra- 

 cemes withafew flowers at the end. These 

 I have an unequally two-lipped calyx, with 

 I the upper lip two-lobed and rather larger 

 j than the lower, which is three-parted ; a 

 ! papilionaceous corolla, with a roundish re- 

 flexed upper petal spurred at the base but 

 destitute of callosities ; and ten stamens, 

 nine of which are united and one free. 

 The pods are furnished with four thin 

 longitudinal wings at the angles, and con- 

 tain from four to eight roundish seeds. P. 

 teiragonolobus, also called Bolichos tetrago-. 

 I nolobus, is grown in India for the sake of 

 its eatable seeds. [A. S.] 



PSORALEA. A very large and most ex- 

 tensively dispersed genus of Leguminosce, 

 consisting of nearly a hundred species, 

 spread over most parts of the American 

 continent, and also found in great abun- 

 i dance at the Cape of Good Hope, more spa- 

 ! ringly in Australia, and still more so in 

 j Asia. The genus is named from the Greek 

 | word psordleos, 'scurfy,' in reference to the 

 plants belonging to it being for the most 

 part sprinkled all over or roughened with 

 glandular dots or wart-like points. They 

 are chiefly small shrubs or perennial her- 

 baceous plants, sometimes with tuberous 

 farinaceous roots, and usually have com- 

 pound leaves composed of from three to 

 five leaflets with the stipules adhering to 

 the stalk.though occasionally the leaves are 

 simple ; and their blue white or purple flow- 

 ers are borne in short spikes or racemes. The 



calyx is flve-cleft and persistent, the tube 

 covered with glands, and the lowest lobe 

 longer than the others ; and nine of the 

 ten stamens are joined together, the tenth 

 being generally free but sometimes joined 

 to the others at the bottom, and the five 

 alternate anthers often imperfect. The 

 oue-seeded pods are seldom longer than 

 the calyx, thick and often wrinkled, and 

 do not split open at maturity. 

 I P. corylifolia is an East Indian erect her- 

 baceous plant growing about two feet in 

 height, having simple egg-shaped leaves, 

 ; slightly heart-shaped at the base, and pale > 

 bluish flowers in dense short spike-like 

 racemes on long axillary stalks. The pods, 

 which are very small, flat and oval or kid- 

 ney-shaped, have an aromatic taste, and 

 are employed medicinally by the native 

 doctors in India ; they also yield an oil, 

 and under the name of Bawchan-seedshave 

 , been sent to this country for pressing. 

 I P. esculenta is a native of Wisconsin, 

 3Iissouri, and other parts of North-west 

 America, where its tuberous roots, known 

 as Indian or Prairie turnips (Pornme 

 Blanche or Pomme de Prairie), form a great 

 part of the food of the indigenous popu- , 

 lation, but when boiled are rather insipid. | 

 I It is a hairy herbaceous plant about a foot 

 j high, with leaves composed of five leaflets 

 I disposed in a palmate manner, and round- 

 ish heads of blue flowers. 

 I In Chili the leaves of P.glandulosa, there 

 called Culen, are used as a substitute for 

 | tea under the name of Jesuit's Tea ; but 

 l their infusion is not very aromatic, and 

 j appears to be valued more for its medicinal 

 i properties than as an agreeable beverage, 

 i being a powerful vermifuge and likewise a 

 j stomachic ; they are also used by the Chi- 

 ] lians for making poultices to apply to 

 | wounds, and an infusion of the root is 

 I emetic and purgative. The plant has been 

 i introduced into the Mauritius, and has 

 '■' there lately acquired a reputation as a re- 

 medy for diseases of the respiratory organs. 

 . It forms a dwarfish shrub, with trifoliate 

 I leaves, and long-stalked racemes of striped 

 bluish and white flowers. [A. S.j 



I PSYCHINE. A genus of Cruciferce, from 

 3Iediterranean Africa, containing a hispid 

 annual, with oblong toothed leaves, those 

 of the stem amplexicaul, and racemes of 

 white violet-veined flowers opposite the 

 leaves, with leaf-like bracts. The pod is 

 triangular, laterally compressed, with a 

 very narrow septum and a beak formed by 

 the persistent style, which is four-sided at 

 the base, and filiform at the tip; valves 

 keeled, winged at the apex; seeds nume- 

 rous, with folded cotyledons. [J. T. S.] 



PSYCHOTRIA. The etymology of this 

 name is somewhat obscure : the generally 

 received opinion is, that it is derived from 

 Greek psyche, 'the soul,' 'life,' in allusion 

 to the active properties possessed by some 

 of the species. Botanically it is applied to 

 a genus of Cinchonacece, consisting of 

 shrubs found in tropical countries, espe- 

 cially in America. The more important 

 characters of the genus are : a nearly entire 



