242 
compared and discriminated (t. 2575). This is the most recent 
revision e ihe eem. but their P esc iota distribution in each 
case is n yet satisfactorily ascertained. In addition to 
those ad above the following are known from North 
Brazil: H. rigidifolia, Muell. Arg., H. discolor, Muell. Arg., and 
H. lutea, Muell. Arg. The latter is found on the Rio Negro and 
also in East Peru. One or two species of Micrandra (with 
simple leaves) are also known as sa and according to Spruce, 
yield a milk containing caoutchou 
It is admitted that the chief ióbolon disini the Para rubber of 
commerce is Hevea brasiliensis, Muell. A g. (Siphonia brasiliensis, 
H. B. K.) the Seringa of the bonum an AA the Para rubber tree 
of the English. This is a slender tree reaching a height of 50 to 
60 feet with a circumference near the base of 6 to 8 feet. The 
leaves are sb Fa earl on long slender petioles. The diclinous 
ers are produced in axillary panicles, the female larger and 
terminal. The fruit is a dry ore vee bes [n ai 
seeded pieces. The s eeds are 
( Collins’ Caoutchou ic, t. 1; Hoo er's Icones S 2575, 
eom "1 Siphonia brasiliensis Hay yne's Gewache, xiv t5. 
report recently ydo to the Foreign Office, by 
Mr. Ooni 1 W. å. ‘Chane hill (7.0. No. 2140, Annual Series, Trade 
of Para and district for the year ist) the. following account is 
given of this rubber tree (pp. 25, 26.) . 
“The Hevea tree is not Med abe and resembles many other 
forest trees. People have travelled fo ls of miles through 
the rubber region v have lived tor years i “in the centres of the 
industry without even noticing it. 'The new-comer invariably 
expects ba see s familiar glossy dark-green leaves of the aw, 
and is dissappointed with the insignificant appearance of t 
Hevea. In habit it is more like the English vias than i 
else. It grows to a height of upwards of 60 fee 
" Pe T inu where rubber-trees thrive the post are on islands 
and | ound near rivers where the banks are periodically 
rules s lesund that is above water at all times or that has no 
drainage is e so suitable to the t 
* A peculiarity of this rubber-tree is, that it will not grow 
ieee on cleared and open gr round. It requires the shade 
of other trees, and still air, from the time that its growth begins 
until it becomes an adult tree. Without these conditions the 
supply of milk is very much affected. In fact, the tree has been 
known to die soon after the clearing of ground ‘around it 
* No cultivation of rubber trees worth mentioning ia been 
aai in the Amazons region. It is considered useless to 
invest capital in cultivation so long as the Amazonian forests 
show no sign of exhaustion 
A very interesting note on the early history of the india-rubber 
industry on the Amazon was communicated by R. Spruce to 
Hooker's Journal of Botany Shy vii., 1855, pp pp. 193-196). This 
gives a graphic account of the beginning of the collection and 
preparat ion of Para rubber. 
* When I ascended the Rio Negro in 1851, I — out to the 
inhabitants the abundance of'seringa trees they po possessed in their 
forests, and tried to induce them to set about Staatl ihe; gum ; 
