STERCULIACEZ. 229 
confounded with Cochlospermum Gossypium, which yiclds a 
similar gum. Possibly it may be the tree spoken of as Balika, 
The gum is collected for sale in most parts of India, and is 
largely used for making native sweetmeats, and as a substitute 
for tragacanth. The seeds yield an oil containing much 
stearin (Hawkes), and are eaten by the Ghonds and Kukus in 
the Central Provinces. (Brandis.) 
’ It has been shown by Van Tieghem that “in the Stercu- 
liacess the gum is produced in large secretory cells formed 
by the separation of contiguous cells, These cells surrounding 
the canals are surrounded by smaller cells, which become 
dissociated as the canal enlarges, and so dliched 4 in appearance 
as to be scarcely recognizable. In Cola acuminata the gum 
canals are present in the pith and bark.” (Bull. Soc. ee 
de France, p. 11, and Pharm. Journ. (8), xv., 8 ve 
Description.—On cutting off a young beads of 
Sterculia urens the gum is seen exuding as a soft solid mass 
from very large canals in the pith and bark, and it appears 
to be contained in the tissues with some tension as the gum 
is extruded in a short time to the extent of about half an inch. 
* The very young portions of the trees, as the branches of the 
panicled inflorescence and the petioles of the leaves also 
extrude thegum. The gum is completely soluble in cold water, 
forming an almost colourless solution. Seen in volume it is - : 
slightly opalescent. Thirty grains dissolved in twenty ounces 
of water forms a thick, tasteless, mucilage, which entirely 
passes through a paper filter. A solution of this strength, 
examined in a column 200 m.m. long, was optically inactive, 
neutral to litmus, and not precipitated by alcohol. A very — 
thick mucilage is, however, precipitated. It is gelatinized by- 
basic acetate, and gives a faint precipitate with neutral acetate _ 
of lead, but is unaffected by ferric chloride or borax and not 
coloured blue by iodine. It is precipitated by boiling wi 
an alkaline solution of cupric tartrate, but the copper is 
_ veduced. The gum treated with nitric acid yields | 
d eerste of mucic acid. It loses 16 per eT 
