MILK TREES, Arbol de leche, Palo de vaca, Arbro de la vache. Milk - yielding plants occur chiefly amongst the Euphorbiacem, Urticacem, and Apocynem, but nearly all their milky secretions contain acrid and deleterious principles. The genera Euphorbia and Asclepias, however, con tain species said to yield a mild and innocuous milky juice. Amongst these are the Euphorbia balsamica of the Canaries. In Ceylon is found the Gymnema lactifera.
The Tabayla dolce or Euphorbia balsamifera of South America should be introduced into India. It grows chiefly in the valley of Caucagua in the neighbourhood of 'Valencia. It was seen by limn boldt and Bonpland on the 1st March 1800, during their expedition to the valley of Aragua, and these authors describe the milk as used freely by the Negroes. On making an incision into the bark of the Palo de vaca, there issues a glutinous and somewhat thick milk, free from all acridness, and possessing a balsamic odour. The travellers
partook of it freely at bed-time, and found no ill effects from it in the morning, and they were assured that the Negro slaves and the freemen used it abundantly, and fattened on it..
Caoutchouc is the dried juice of several plants — the }levee Guyanensis, Vahea gummifera of Mada Siphonia cahuchu, Siphonia elastics, the Haucornia speciosa of Brazil, the.Jatropha elastics, the Urceola, elastics of Sumatra, the Willughbeia cdulis of the East Indies. In A.D. 1736, La Condamind directed attention to the eaoutchouc from the Siphonia elastics. Fremeau discovered the !fovea at Cayenne, and mentioned that longi tudinal or oblique incisions were made through the bark, and the fluid, white-coloured sap directed by an inserted leaf to an earthen pot below.— Marion, pp. 49, 138.