446 I'AUNASSIA. [CLASS V. ORDER IV. 



ORDER IV. 



TETRAGYNIA. 4 Pistils. 



GENUS XCIX. PARNAS'SIA.— Linn. Grass of Parnassus. 



Gen. Char. Cahjx five-parted, spreading. Petals five, veiny, and 



opjjosile the base of eaeli is an heart-sliaped flesliy scale, fringed 



wiili slender bristles, lipped with globular glands. Stiijinaa four, 



sessile. Capsule superior, of one cell, opening at the apex «ilh 



four valves, each with a linear placenta bearing numerous needs. — 



Named from Mount Parnassus, though the plant is by uo means 



peculiar to that situation. 



]. P. palus'tris, Linn. (Fig. 509.) Common Grass of Parnassus. 



Scales with from nine to thinecn bristles; root leaves on footstalks, 



heart-shaped, the solitary one of the stem amplexicaul. 



English Botany, t. 82. — English Flora, vol. ii. p. 114. — Hooker, 

 British Flora, vol. i. p. 147. — Liudley, Synopsis, p. 67. 



Root of numerous long branched fibns. Stem erect, angular, 

 striated, twisted, from " one inch" to eight or twelve high, quite smooth, 

 as is the whole plant, wiih a solitary leaf below the middle, sessile, 

 and embracing it. Leaves from the root numerous, on rather long- 

 channeled footstalks, heart shaped, more or less acute ai the point, not 

 iinfrequently rounded, with a mid-rib and several lateral ones from the 

 base, paler beneath, and more or less profusely scattered over wiih 

 small oblong glands, of a pinkish colour, sometimes wanting, but best 

 seen in dried specimens, they are also numerous on the footstalks and 

 lower part of the stem. Flower solitary at ihe top of the stem. Calyx 

 five-partite, the segments ovale, acute, with numerous slender longi- 

 tudinal veins, spreading. Corolla of five broadly ovate obtuse spread- 

 ing concave petals of a beautiful white, with numerous pellucid veins, 

 and sometimes, though rarely, the margin is fringed, the base with a 

 short claw, and opposite to it is a fieshy heart-shaped scale, on a short 

 stalk, having the margin fringed with from nine to thirteen awl-shaped 

 slender bristles, each tijiped with a small round yellow gland. Stamens 

 alternating with them, and about the same length, with awl-shaped 

 filaments and oval anihers, pale cream colour, of two cells, bursting 

 longitudinally. St'ujmas four, sessile, obtuse, spreading, crowning the 

 capsule, which is broadly ovate, marked with four longitudinal furrows, 

 nearly superior, of one cell, bursting about halfway down from the 

 apex, each with a longitudinal lateral placenta, bearing numerous 

 small brown seeds, curved upwards, with a narrow membranous border 

 all round. 



