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much alike, for Robert Brown tells us that so learned a man as Rumphius confused the two species. The 
action of poele bark is the same as dita, only it contains, as I have already mentioned, six times the 
amount of alkaloid ditamine. 
Other species of this genus are met with in South America and the East Indies, and their barks 
are employed in the treatment of dysentery, diarrhoea, malaria, and debilitating diseases ; but they only 
enjoy a local celebrity. 
Alstonia conslricta, F.v.M.—The bark is of chief interest to us ; specimens vary a good deal in 
bitterness, and old specimens appear to have lost much of their bitterness. Some specimens have very 
little periderm. 
This leads me to an important point and relates to the question of the wisdom of the compilers of 
the Addendum in making no distinction between A. conslricta and A. scholaris so far as it deals with the 
tincture and infusion. The Indian bark may, it is true, be generally employed in India, and the Australian 
bark in Australasia; but the preparations are sure to be used to some extent in other Colonies and in the 
home countries, and if a medical man prescribes the tincture or the infusion of Alstonia, it is left to the 
option of the dispenser to supply what he likes. Now the A. scliolaris preparations are light in colour and 
pleasantly bitter, while the A. conslricta preparations are darker and very bitter, and if one pharmacist 
supplies the first, and his neighbour round the corner supplies the second, the next time the patient has 
his prescription dispensed, it may lead to confusion. It should be noted that the tincture and infusion are 
simply called tincture or infusion of alstonia—the specific name is not given. In my opinion the dose of 
the tincture made from A. constricta is too large. Tt should be 5 to 20 minims, and not ^ to 1 fluid drachm 
as given in the Addendum. The dose of | to 1 fluid drachm is appropriate for the A. scholaris preparation. 
As to the determination of the relative bitterness of the two barks in a rough way, I do as 
follows:—I chew the bark and note by the w'atch the time of the development of the bitter taste, and 
also its intensity. The bitterness of A. constricta develops in ten seconds at the latest, and is intense; 
while A. scholaris does not develop bitterness before fifteen seconds at the earliest, and not usually till 
nearly twenty seconds, anil at the end of this time it is only mildly bitter. 
Tests applied to the Dry Inner Bark. —The following on being applied to the inner layer of the 
bark give :—(1) Solution of iodine—mahogany brown (compare dita bark). If a watery infusion be placed 
in a porcelain dish, and then iodine solution be added thereto and heat applied for ten seconds, a mahogany 
brown is obtained. On cooling, there may be observed on the bottom of the dish, in parts where the 
watery portion has evaporated, beautiful puce-coloured masses. ( 2 ) Strong EeCl 3 , no characteristic reaction. 
(3) Chromic acid solution, no characteristic reaction. (4) Bromine solution, no characteristic reaction. 
(5) Strong H 2 SO 4 , no characteristic reaction. Compare dita. ( 6 ) Strong HC1, no characteristic reaction. 
(7) Strong I1N0 3 , a beautiful garnet red, and not so far removed from the so called blood-red of nux 
vomica bark. If a watery infusion have added to it a few drops of nitric acid (strong), the same delicate 
hue results, but soon changes to brownish-green. Compare dita. 
Active Constituents of the Bark. —There are four alkaloids: (1) alstonine; (2) porphyrine; 
(3) porphyrosine; (4) alstonidine. Alstonine, the first, is very bitter, and is the only one of any great 
importance. Accepting O. Hesse’s classification, alstonine is the alkaloid which was formerly known as 
chlorogenine. Its formula is estimated as C 21 H 20 N 2 O 4 . This was a brown amorphous powder nearly 
soluble in chloroform and alcohol, sparingly soluble in water and dilute acids, and insoluble in absolute 
ether. Some books describe the alkaloid as being of a golden brown colour ; but Hesse simply says it is 
brown. Its solubilities are differently stated in different books. This may be owing to the fact that 
alkaloids more or less impure have been employed. My specimen was alkaline to litmus and its watery 
solution, yellowish brown, and fluorescent and bitter in the extreme. I tested it carefully with phenyl- 
hydrazin for sugar, but failed to get any reaction, so that in all probability there was no admixture of 
glucoside. It was difficult to believe that such a brown body did not contain some glucosidal colouring 
matter. (Peruvian bark is in colour much like bitter bark, and yet its chief alkaloid quinine is quite 
white.) Alstonine readily forms salts with most acids. I have only experience of the hydrochloride, 
which is fairly soluble. 
Reactions of Alstonine. —This alkaloid was put through a large number of tests in the hope of 
finding some characteristic colour or other reaction. Heated with strong HC1, H 2 S0 4 , or HN0 3 , a 
sweetish odour is developed. Strong II 2 SO 4 by itself gives no particular reaction, but if a small crystal 
of cane sugar be added, a puce or garnet results. Like the bile salt tests, it must be carefully carried out 
in order to ensure success. Strong H 0 SO 4 with a trace of HN0 3 gives a brownish red, while 11N0 3 by 
