8. H. LutEA, Mull. D’Arg. Leaflets rigidly membranous, 
obovate-Ianceolate, with the base sharply cuneate, shortly acumi- 
nate, olivaceous-tawny, opaque, below glaucous, tawny, glabrous, 
on both sides, of om, io-o m , 012 in length. 
9. H. BRASILIENSIS, Mull. D’Arg. Leaflets rigidly membra- 
nous, lanceolate-elliptical, oblong-obovate in the middle, acute at 
base, acuminate, glaucescent. and glabrous below, of o™. 05-om, 
07 x o m , 08 in length. 
10. H. GUYANENSIS, Aublet. Leaflets membranous, oblong- 
obovate, with the base acute or cuneate, obtuse or apiculate, gla- 
brous, shining above and tawny-glaucous below, shorter than the 
petioles and of o m . 25 x o m , 08 in length. 
The first to have classified the rubber three (Hevea Guianensis) 
was the French Botanist AyBLET in 178b ar *d RICHARD in 1 785, 
who described it by the name of Caoutchouc . SCHREBER in 1879* 
not adopting Aub let’s description, created for it the genus 
Siphonia. But LlNN/EUS in 1781, had already placed it under the 
genus Jalropha, with the specific name of elastic a, while PERSON 
renamed it later on Siphonia adding to it LlNN.EUS’s specific name, 
which WlLLDENOW eventually altered into cahuchu. The name 
Siphonia elastica was the one by which this tree was more com- 
monly known at the time rubbers belonged to the Hevea, by right 
of priority and because this said genus Siphonia was no more than 
a synonym. 
The names caoutchouc and seringa belong to all the species ol 
Heveas, the word cdocho being to-day applied to the Castilloas and 
Galactodendrons. The name coacho , is, as we have seen, a coi- 
ruption of caaocho or caaochu , a native word derived from caa 
wood, timber, and the verb 0 chd or 0 chu to distil , or lo run or 
weep , in other words, timber that weeps. 
In some places, rubber is obtained from one species only of the 
local flora growing together, in others, there is promiscuity and the 
consequent mixture of milks, trom which results the various 
qualities of the prepared article, an occurrence common also with 
the oil of copaiba. 
Among the species that produce the superior qualities of rubber, 
are others called barngudas , which notwithstanding that tney pro- 
duce milk in abundance, is however, poor in rubber and of bad 
quality at that. This name of barngudas is derived from the fact 
that some of these trees have bellied on bulging trunks, as often 
occur on the margins of the Amazon. The true rubbers, those that 
produce rubber of the best quality, are the H. Brasiliensis, the 
//. Discolor and the H. Guyanensis , all of which are rich- in the 
production of a milky juice, known scientifically as latex. 
This milk is exuded from the trunk, the. branch, the bough and 
the petioles; however, it is only that which exudes from the tiunk 
that is of any use, that from the extremities being aqueous and 
poor in rubber. The nearer it is to the ground, the greater the 
abundance and the better the quality of milk the trunk produces. 
This milk* which constitutes the wealth of the tree, is a white 
* Dissolved in small quantities bTcastor oil, it has anthelmintic properties. 
