219 



That amylaceous feeula, which the seeds of the 

 cereal plants furnish 'in all it's purity, is found 

 united with an acrid, and sometimes even 

 poisonous juice, in the roots of the arums, the 

 tacca pinnatifida, and the iatropha manihot. 

 The savage of America, like the savage of the 

 islands in the Pacific Ocean, has learned to dulcif y 

 the fecula, by pressing and separating it from 

 it's juice. In the milk of plants, and in the 

 milky emulsions, matter extremely nourishing, 

 albumen, caseum, and sugar, are found mixed 

 with caoutchouc and with deleterious and caus- 

 tic principles, such as morphin and the hydro- . 

 cyanic acid % These mixtures vary not only in 

 the different families, but also in the species 

 which belong to the same genus. Sometimes it 

 is the morphin, or narcotic principle, that cha- 

 racterizes the vegetable milk, as in some papa- 

 verous plants ; sometimes it is caoutchouc, as in 

 the hevea, and the castilloa; sometimes albumen 

 and caseum, as in the cow-tree. 



The lactescent plants belong chiefly to the 

 three families of the euphorbiaceae, the urticese, 

 and the apocineae -f* ; and since, on examining 



* Opium contains morphin, caoutchouc, &c. 



+ After these three great families follow the papaveraceae, 

 the chicoraceae, the lobeliaceae, the campanulaceae, the sapo- 

 tas, and the cucurbitaceae. The hydrocyanic acid is peculiar 

 to the group of rosaceo-amygdalaceae. In the monocotyledon- 

 bus plants there is no milky juice j but the perisperm of the 



