VIOLACE^E. 



141 



of water producing a consistent jelly. From the strong proofs brought for- 

 ward of the efficacy of these plants in the treatment of chronic diseases of the 

 skin, they well deserve a further trial, and as the V. tricolor is to be found in 

 every garden, the fresh herb can always be procured. 



Ionidium. — Ventenat. 



Sepals small, membranaceous at margin, unequal. Petals unequal, marcescent. Sta- 

 mens five, approximate. Filaments short, dilated, bearing the anthers near the base. 

 Ovary sessile, 1-celled, 6-seeded. Style declined. Pericarp 3-valved, with a loculicidous 

 suture. Seeds shining, truncate at apex. 



The species composing this genus was formerly included in Viola, until 

 separated by Ventenat. They are herbaceous or suffruticose plants, mostly 

 peculiar to South America, two species only occurring in the United States. 

 It was at one time supposed that the Ipecacuanha was the product of one or 

 more plants of this genus, as the roots of the whole or of the greater number of 

 them are endowed with analogous properties, and are much used as substi- 

 tutes in Brazil. The most prominent of them are the I. ipecacuanha, I. par- 

 viflorum, and I. microphyllum. 



I. ipecacuanha, Linn. — Hirsute. Stem erect, herbaceous. Leaves alternate, lanceo- 

 late, acutely serrate. Peduncles bibracteate, axillary, solitary. Calyx glandular, dentate. 



Aublet, Guian. 313; Ventenat, Malm. 23; Martius, Spec. Mat. Med. 

 Bras. 14 ; Lindley, Flor. Med. 98. 



Description. — Root perennial, ligneous, perpendicular, four to six inches in length; the 

 old roots about the size of the little finger, the younger about that of a goose-quill. Stem 

 cylindrical, branching, somewhat pilose. Leaves alternate, obovate, acute, dentate, on a 

 short petiole, and having two linear stipules at base. Flowers pedicellate, solitary, with 

 two or three small, linear bracts. Calyx hairy, glandular. Corolla irregular, two upper 

 petals narrow, and not longer than the sepals, the two lateral broad and twice the 

 length, the inferior still longer. Stamens distinct. Anthers not connate, having a mem- 

 branaceous appendage at their apex. Pericarp almost triangular, 1-celled, 3-valved. 



This species occurs very plentifully in sandy soils in Brazil, Colombia, and 

 some of the West Indian islands, flowering in July and 

 September. It is known in Brazil under the name of 

 Ipecacuanha branca, or white vomiting root, and is 

 much prized by the inhabitants as an emetic. Martius 

 states that he often observed large parcels of it dried 

 and kept for use. The mode of preparation is to shave 

 the cortical portion from the root, and infuse it in 

 water for twelve hours ; the dose of the infusion is 

 from half a drachm to a drachm, in which quantities it 

 acts mildly, but with much certainty. This root has 

 been known in commerce under the name of white 

 Ipecacuanha, and is sometimes to be found mixed with 

 the true article, but may always be distinguished from 

 it, by its want of the rings so characteristic of the 

 genuine drug. Its properties, however, seem almost 

 identical with the real Ipecacuanha, and the analysis 

 of it by Richard shows that its chemical composition 

 is very analogous to it. A sufficient number of expe- 

 riments have not been made with it to establish its exact 

 value, but it would appear from all that is known re- 

 specting it, that it might be used instead of the true 

 Ipecacuanha, without inconvenience. Root of I. ipecacuanha. 



Fig. 79. 



