CONVOLVULACEA. 529 
he pronounced it unworthy of a place in the Pharmacopotia. 
‘In this opinion he is undoubtedly correct, as the active resins 
are present in the root in a much smaller proportion than in 
jalap, but as the drug is very cheap it might be used with 
it Ae iien inflamtintlgeer the gastro-int mbrane 
_ and bloody dejections, Like jalap itis an faye stimulant, 
increasing the secretion of biliary matter and rendering it more 
watery. Being’ a hydrogogue cathartic itis useful for the 
_ removal of dropsical effusions, and in such cases it acts best in 
combination with ginger and bitartrate of potash. The dose 
t 
Be abtion. The Turpeth of commerce consists of the 
lisot and stem of the plant cut in short lengths, usually from 3 
to 2 inches in diameter; the central woody eee is hes 
of a dull grey colour, a transverse section shows a porous sur- 
face of a dirty white colour, and loaded with pale yellowish- 
white resin; through this substance pass numerous bundles 
composed of large vessels and woody fibre. The drug is free 
from smell, but has a nauseous taste, which is only perceptible 
after it has been some time in the mouth. In some specimens 
all or a portion of the central wood remains; it resembles a 
piece of rattan cane. Black nisot presents a similar appear- 
ance, but is of smaller size and of a darker colour. 
Microscopie structure.— The epidermis consists of tebuslne 
‘born, cells; the parenchyma is starchy, in it are thickly. 
‘Seattered very large resin cells and numerous rosette-like 
