20 
cells, Below the dicc uis we find a few layers of large chloro- 
bundles, the main trunks running longitudinally, and connected 
by branching and anastomosing lesser bundles. ‘The longitudinal 
bundles have a strong group of. frien viernes end cells accom- 
panying them on their inner side, and immediately beneath them 
we find a large mass of circularly running cells of the same 
nature, forming quite a dense coat of hyphae-like thin-walled cells, 
showing their cell-walls very distinctly when the caoutchouc has 
been dissolved out by chloroform.” 
These oa as iege did not settle the d of the gen 
and Mr. Weiss left the matter with the remark that perhaps the 
tribe Unona might include Zucommia in n préfefenóe to Phyl- 
lantheae of the same order—Euphorbiaceae. 
Since these first researches, made on imperfect material, further 
knowledge has been due to the success of scientific and horti cul- 
tural establishments in Paris in obtaining first dod flowering 
specimens and now living plants. From the museum t 
o 
rR 
D 
antes came 
enabled to publish a second figure (Hooker’s Icones Plantarum, 
t. 2361), and Dr. Solereder’s researches tci der Deutschen 
botanischen Cele xvii, 1899, 387) were made upon 
flowers sent to him from Pari s and fruits supplied from Kew ; 
while the living plants in salit vatfon at the Jardin Colonial, in 
the garden of the Faculty of Medicine, and by the firm of 
id mination of the dried flowering specimens which had been 
received in 1894 from a French missionary— ére Farges—and 
were taken from trees cultivated in Szechuen, caused Professors 
Oliver and Baillon to agree in placing Hucommia in the order 
drae o i a 
ea ac 
impossible to discuss here the cause of this difference of opinion ; 
let it suffice to say that it indicates the difficulty experienced in 
assigning to its true position this peculiar genus. Wherever from 
external morphological characters we place it, the allied Le 
are not rubber- or gutta-yielding plants. Solereder observ es this, 
and compares in justifica ation of his view the Hippo repite in 
which caoutchouc cells are found in certain speci 
There are great differences between the caoutchouc cells of 
Eucommia and of the Euphorbiaceae. In the latter the whole 
system is one com plicated network arising from the branching of 
cells which are present in the embryo, which grow with grow- 
ing plant, ramifying and uniting, so that the outflow of one cut 
vessel is more a its contents, because other vessels feed it as it 
bleeds. In Zucommia the caoutchoue vessels do not branch and 
‘their contents, too, are more of the nature of gutta percha than 
indiarubber ; and iu structure they are much more similar to the 
