318 VIOLA. [CLASS V. ORDER 1. 



plant, we should find the same display of wisdom and admirable 

 design, even in the minutest of the varied vegetable forms. There is 

 another curious circumstance connected with the plants of this genus, 

 we mean the capsules, and the bursting open of their valves with a 

 sudden elasticity. If a transverse section of the more or less angular 

 capsule is made, it will be seen to consist of one cell with three valves, 

 and that each valve has at the angle a stout column of cellular matter, 

 thicker in the lower part than above, and its two sides of a thin mem- 

 branous substance, which are united to those of the other valve by a 

 very thin transparent membrane. The inner edge of the central column 

 is the placenta, on which the seeds are attached by a very short slender 

 cord, by which they are nourished until they are matured, at which 

 time, when there is no further demand for the continued flow of fluid 

 in the cellular substance or other parts of the capsule, it gradually 

 dries up ; but as the cellular column contracts much more than the 

 membranous sides of the valves by drying, it is constantly exerting a 

 power to pull bade the valves, which is resisted so long as the thin 

 membrane which unites the edges of the valves has power, which, 

 however, at length gives way, and mostly by a sudden tear, by which 

 motion the seeds now loosely attached are thrown to a considerable 

 distance from the plant. This operation is generally performed during 

 the day, while the sun is shining upon them and drying them, when 

 their elastic power is greatest ; for when the humid dew falls upon 

 them a portion of it is absorbed, and consequently the valves become 

 relaxed. We have here endeavoured to describe the structure and use 

 of the parts of a flower of remarkable formation, in the hope that the 

 student of nature will be induced to examine it himself, and not rest 

 satisfied with reading an imperfect account ; and he will then find 

 how difficult it is to read with satisfaction the real book of nature, and 

 as difficult to describe even that which we think we know. But let 

 him not rest satisfied with the examination of this plant only, for he 

 will find many others equally familiar to him as the sweet smelling 

 Violet, that will fully compensate him for the trouble bestowed upon 

 its investigation. 



3. V. pahis'tris, Linn. (Fig. 386.) Marsh Violet. Leaves heart or 

 kidney-shaped, quite smooth; calyx segments obtuse; spur very short; 

 lateral petals nearly smooth ; capsule smooth, without runners. 



English Botany, t. 444. — English Flora, vol. i. p. 303. — Hooker, 

 British Flora, vol. i. p. 121. — Lindley, Synopsis, p. 35. 



Root small, branched, and fibrous, without or with very short 

 runners. Leaves mostly few in number, quite smooth, on longish 

 footstalks, from the bosom of small thin membranous stipules, the 

 footstalk is channeled, and frequently slightly winged near the top, 

 the leaf kiducy-shitped, with a heart-shaped base, the margin crenated 

 more or less deeply, paler on the under side and veiny, the veins all 



