312 MEDICAL BOTANY. 



The root, which is the part employed, is spongy, and has a very disagreeable 

 odour, and an extremely nauseous taste, depending on an acrid principle which 

 can be removed by washing, so as to leave a pure and nutritive fecula, which 

 was used in France during a time of scarcity, and found very nutritious. The 

 root has been analyzed by several chemists, and shown to contain fecula, a pe- 

 culiar acrid principle (bryonine), gum, several salts, &c. Collard de Mar- 

 tigny (Nouv. Bib. Med. ii. 219) is of opinion, that bryonine, although very 

 active, is not the only purgative principle in the root. 



Medical Properties. — Bryony is an energetic purgative and emetic, and 

 was known to the ancients, as both Dioscorides and Pliny recommend the 

 juice in epilepsy, and it was also much used in other cerebral affections, and 

 also in dropsy, and many other complaints. As the properties of the root 

 depend upon the acrid juice, the root should be dried for use in such a way 

 as to prevent the volatilization of this as much as possible. The infu- 

 sion is the best mode of administering it where its purgative powers are desired ; 

 for this purpose half an ounce of the dried root is to be infused in a pint of 

 boiling water, to which some aromatic may be added ; of this a wineglassful, 

 taken every four hours, will produce copious evacuations, both from the bowels 

 and bladder. In France the juice is a common domestic purge ; this is pro- 

 cured by cutting off the vine, scooping a hole in the root, and collecting 

 the fluid that exudes into it. It was also celebrated for its wonderful anthel- 

 mintic powers, and for its emmenagogue qualities. When given in powder, 

 in doses of half a drachm, it acts as an emetic, followed shortly afterwards by 

 purgation. The recent root is capable of blistering the skin, and has been 

 found useful in rheumatic affections, and for the removal of extravasated 

 blood. 



Most of the other species a^e likewise active ; the B. africana, according 

 to Thunberg, is used at trie Cape of Good Hope as an emetic and purgative, 

 and Ainslie states that the seeds of the B. callosa are used in India as a ver- 

 mifuge, and the B. epigcea, according to the same authority, is regarded by 

 the Hindoo physicians as one of their most valuable remedies, in dysentery, 

 inveterate venereal affections, and as a vermifuge. 



Group XXL — Saxifragales. 



Order 52.— SAXIFRAGACEiE— Jussieu. 



Calyx of 4 — 5 more or less united sepals, either free from, or more or less adherent to 

 the ovary ; persistent. Petals as many as the sepals, rarely wanting-. Stamens as many, 

 twice as many, or rarely 3 — 4 times as many as the sepals. Ovaries usually 2 (some- 

 times 3 — 4,) usually united below, and distinct at summit. Seeds numerous. 



This very extensive order consists of herbs or shrubs with alternate or op- 

 posite leaves; it is divided into four sub-orders, the first of which, the Saxi- 

 fragece proper, is composed of herbaceous plants only, whilst the other three 

 are all shrubs. The roots of many of them are astringent, but the only 

 genus that is entitled to notice for its medicinal properties is Heuchcra. 



Heuchera. — Linn. 



Calyx campanulate, 5-clefl. Petals 5, small. Stamens 5, exserted or included; an- 

 thers 2-cclIed. Styles 2. Capsule 1 -celled, with two parietal adnate placentas; many- 

 seeded, 2-beaked, dehiscent between the beaks. 



