276 APETALEX, 
ed, according to Richard, deposits a white farinaceous pow- 
der, which is tapioca. Dr. A. T. Thomson applies the term 
_ Tapioca to the matter which is here called Cassava. Ca- 
outchouc is furnished by Hevea guianensis, 
Meprcinat Prorertres.—The Euphorbiacee are im- 
portant in a medicinal point of view. They are, in general, 
very acrid and irritating; these properties reside in the 
milky juice in which they abound. The acrid principle, 
however, is very volatile, and easily expelled by heat. Gum 
euphorbium is the produce of Euphorbia officinarum, and 
also of E.. antiquorum and E. canariensis ; it is an active, in- 
deed violent emetic, cathartic, hydragogue, and errhine. 
The thick oil in the seeds of Caper Spurge (Euphorbia la- 
thyris), and in those of E. Cyparissias, has similar properties. 
. The roots of Euphorbia Ipecacuanha, E. sylvatica, E, Ger- 
ardiana, E. Cyparissias, and E. pithyusa, are said to be excel- 
lent substitutes for Ipecacuanha. The bark of Croton Cas- 
