278 
PROCEEDINGS OF SECTION B. 
have been able to ascertain, has a yellowish colour, and gives a 
brilliant green colouration, which rapidly passes into brow'n when 
moistened with a drop or two of sulphuric acid. In one experiment 
a small quantity when injected produced in a frog gradual paralysis 
of the limbs, followed subsequently by violent convulsions and death. 
We wish it to be distinctly understood that the discovery of this 
alkaloid is due to Dr. Bancroft. 
9. — PRELIMINARY NOTES ON THE BARK OF CARISSA OVATA, 
E. Be., YAE. STOLONIFERA , Bail. 
By J. H. MAIDEN and H. G. SMITH. 
Dr. T. L. Bancroft, of Brisbane, communicated a paper to the 
Royal Society of New South Wales, read 6th June, 1891, giving the 
results of his observations to that date on the bitter poisonous con- 
stituent contained in the bark of Cor ism ova to, R. Br., var. stolonifera , 
belonging to the natural order Apocynacese. It will be unnecessary to 
quote the references and extracts given by him in reference to the 
poisons obtained from the plants belonging to this natural order, and 
used as arrow poison by the natives of Central America. The reader 
is referred to the above paper for this and other information. 
Dr. Bancroft forwarded some of the bark to the Sydney Techno- 
logical Museum for investigation and determination 'of the nature 
of this poisonous principle. It was with difficulty that the substance 
could be obtained sufficiently pure for investigation, and it was not 
until quite recently that w T e succeeded in obtaining it sufficiently pure 
for chemical research. 
The process whereby the substance is obtained, by the use of 
acetate of lead, either neutral or basic, must be condemned in a 
general way, as it is impossible to obtain the glucoside undecomposed 
when sulphuretted hydrogen is used to remove the lead. "When an 
aqueous solution of the bark is obtained and precipitated with neutral 
acetate of lead, some of the glucoside is removed with the colouring 
matters, tannic acid, &c., although the glucoside itself is not precipitated 
by the neutral lead salt. If to the filtrate from this precipitate basic 
acetate of lead is added, a yellowish precipitate forms, which is 
partly soluble in the liquid, as on adding more of the salt a further 
precipitate is obtained. This yellowish precipitate was decomposed 
with sulphuretted hydrogen, the lead removed, the filtrate evaporated to 
a honey consistence over the water bath at a low temperature, when a 
brownish mass was obtained ; this readily reduced an alkaline copper 
solution in the cold, and was very impure. Another aqueous solution 
was obtained, evaporated down, and the mucilage removed by alcohol, 
and an aqueous solution from this was precipitated in fractions with 
basic acetate of lead until the filtrate ceased to give any marked 
reaction with ferric chloride solution. The filtrate was then treated 
with sulphuretted hydrogen to remove the lead in solution, filtered, 
and the filtrate evaporated to a pasty mass, which darkened greatly 
and was found to be greatly decomposed, readily reducing the copper 
solution in the cold. The method whereby Dr. Bancroft obtained his 
material was also tried, by precipitating the aqueous solution with 
