179 
Further investigation of the flowers of Hucommia and especially 
of the pistillate ones, would seen oe in order if possible 
to gain new light on its real affinitie 
ANATOMICAL. Prof. Weiss* in 1892 worked out the develop- 
ment, distribution, and microscopical characters of the cells 
which elaborate these “elastic” threads in Hucommia. He also 
investigated to some extent the substance itself extracted from 
the bark. 
Barthelat+ and Dybowski et Front have since supplied extra 
details regarding the structure of these ea percha producing 
elements and their distribution in the pla 
This tree might repay further study paid the anatomical 
side. The wood especially requires minute examination. 
Facts might possibly be forthcoming which would throw light 
on its relationship. 
THE GuTTa-LIKE MaTEeRIAL. Weiss considered the substance 
composing the “ elastic ” threads of the bark to be of the nature 
of caoutchouc from its behaviour towards solvents. Conse- 
quently the specialised elements in the plant holding this 
material came to be termed caoutchouc-containing cells, and 
the tree itself to be spoken of as a rubber-yielding one for 
temperate climates. 
Dybowski et Front from their economic enquiry came to 
the conclusion that the substance is much nearer akin to gutta- 
percha than caoutchouc. A French authority to whom they 
submitted a sample declared it to be gutta of good quality. 
Sievers§ in a recent paper, apparently unaware of the French 
work, treats the substance as rubber and investigates its 
solubilities in various media. 
In order to arrive at a rough idea of the amount of this 
material contained in the bark, Weiss ground up some of the 
latter and then extracted it with chloroform. He obtained a 
yield of 3 per cent. Oliver working independently with another 
sample of bark secured the same yield. Sievers by ether 
extraction obtained only a yield of 2 per cent. Dybowski et Fron 
estimated quantitatively the amount in the dried leaves and 
found that the percentage of gutta reached 2°25. The fruits 
were richer in the substance. Apparently the percentage in the 
bark was not ascertained by them 
In 1910 two bales of Eucommia bark secured in China came 
into the writer’s possession. One bale contained 56 lbs. of bark 
and the other, though not weighed, presumably held half this 
quantity, judging from its size. During the re boom of 
a i me 
* Weiss, F. E., Trans. Linn. Soc., London, 2nd ser. Bot. II, 1892, 
p. 243. 
+ Barthelat, Journ. de Bot. xiv., 1900, p. 55. 
b wski et Fron, Comptes Rendus, exxix., 1899, p. 558. 
§ Sievers, A. F., Journ. Amer. Chem. Soc., xxxix., 1917, p. 725. 
Az 
