March 2, 1872.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
707 
I regret that a larger number of the trees has not been 
planted, hut as the yield of hark from the present plan¬ 
tations will shortly he so large, I cannot now recom¬ 
mend any considerable extension, even with this sort. 
11. In a report appearing in Proceedings Madras 
Government, Revenue Department, No. 334, paras. 22 
and 23, I had occasion to remark that in the harks of 
C. succirubra and officinalis a high mean temperature 
appeared unfavourable to the production of quinine, that 
alkaloid occurring more readily in the hark of trees 
grown at high elevations, within certain limits. I have 
met with a remarkable illustration of this principle also 
in the hark of C. Peruviana. The hark of this tree 
grown at Neddivuttum generally contains no quinine 
whatever, and, at best, contains it in so small an amount 
that it is with difficulty it can he clearly detected. But 
the superintendent of the plantations has with great 
judgment experimentally planted several of these trees 
at Dodabetta Plantation, where they grow with much 
tdifficulty, from the cold being too great for them. An 
analysis of the bark of one of these trees gave the fol¬ 
lowing results, to which, for comparison, I attach an 
Analysis of the bark grown at Neddivuttum. 
Dodabetta. 
Total alkaloids 
2-06 
•Quinine. 
Ginchonidine and cinchonine. 
Sulphate of quinine obtained crystallized . . 
Sulphate of cinchonidine obtained crystallized 
Neddivuttum. 
Total alkaloids. 
6-25 
Soluble in ether 
Ginchonidine . 
Ginchonine . 
0-41 
2-00 
3-84 
‘^Sulphate of cinchonidine obtained crystallized 
1-80 
Though the bark of C. Peruviana from Neddivuttum 
(Contained a small amount of alkaloid soluble in ether, it 
was not quinine. But by growing the same species at 
the higher elevation of Dodabetta Plantation, its bark 
quite alters its character, and yields in analysis an 
Amount of pure quinine, which readily crystallizes as 
sulphate. Indeed, the bark thus grown far more re¬ 
sembles the bark of C. succirubra than a grey bark. I 
cannot but consider this instance of a total change of 
Alkaloid, by increase of elevation, a most interesting 
one. 
12. The occurrence of several remarkable varieties 
Among the trees raised from seed has directed my atten¬ 
tion to the occurrence of hybrids among our species of 
cinchona. In one instance I was able, from the account 
given by Mr. C. Dawson, then Assistant Superintendent 
at Neddivuttum, to directly trace the origin of a very 
beautiful plant, which was found to be a hybrid be¬ 
tween C. succirubra and micrantha. This plant was 
picked up a seedling under a tree of the latter. I 
Analysed its bark, and found its yield was poor, but 
represented a mean between the qualities of the two 
species. Examination among seedling trees led to the 
■discovery of many other examples of hybridism, espe¬ 
cially to cross-breeds between C. succirubra and officinalis. 
In 1870 I communicated a short memoir on the subj’ect 
to the Linnean Society.* The occurrence of the dimor¬ 
phic varieties, “macho” and “ hembra” in each species 
■of cinchona was shown in this communication to render 
•cross-breeding highly probable, in the same manner as 
* Read, March 3rd, 1870. 
has been shown by Darwin to occur in Primula , Oxalis, 
and other plants. I learn from the discussion which 
took place on the subject at the Society’s meeting, that 
the fact of the tendency of cinchona to hybridism was 
considered proved. Since that time I have made nume¬ 
rous analyses of the bark of various hybrids that I have 
observed, but in no one instance have I found any of 
special excellence. In fact, it appears to me that these 
hybrids combine the bad qualities of both their parents. 
I therefore do not quote the analyses. 
13. I cannot but think that this ready hybridism be¬ 
tween the species of cinchona affords an explanation of 
the occurrence of the numerous varieties which have 
been recognized by botanists. I observe, for instance, 
that a most recent classification gives thirty-three un¬ 
doubted species, and nearly eighty separate varieties of 
cinchona. On our plantations there are several plants 
which, though certainly hybrids, would undoubtedly be 
made into species by a botanist ignorant of their origin. 
It seems therefore not improbable that several species, 
to which a separate name has been attributed, may be 
only South American hybrids. It is to be hoped that 
in any future botanical classification of the genus this 
circumstance may be borne in mind. 
14. This fact of the inter-breeding of the species 
renders the seed of a tree, surrounded with many others 
of a different kind, subject to conoiderable uncertainty 
of producing all plants like its parent. As a fact, the 
seeds of the variety I called provisionally lanceolata, 
gave but few plants which resembled their parent, and 
consequently the seedlings had to be discarded. As the 
tree producing the seeds was surrounded on all sides by 
the ordinary crown barks, the variation in the seedlings 
becomes intelligible. 
15. I observe that Dr. Weddell, in his “ Notes sur les 
Quinquinas ” (‘ Annales des Sciences Naturelles,’ 5me 
serie, tomes xi. and xii.), and, at the suggestion of Mr. 
Howard, calls the valuable variety I called lanceolata, 
above alluded to, Cinchona officinalis, Ponplandiana an- 
gustifolia, remarking that lanceolata does not express so 
well as angustifolia the peculiar shaped leaf. I would 
suggest that the name angustifolia be, in future, adopted 
as the name of the variety. 
16. In several preceding reports I have abundantly 
stated my convictions, and their grounds, for consider¬ 
ing that living cinchona bark has its yield of alkaloids 
injured by exposure to sunlight. The experimental evi¬ 
dence of this already adduced appears to me to be quite 
conclusive of the fact, so that further proof is scarcely 
needed. Further proof appears, however, in the circum¬ 
stance of which I have been for some time aware, that 
the bark of opposite sides of the same tree differs in 
yield of alkaloids. This, of course, is only fully appa¬ 
rent in trees that are equally exposed to sunlight on 
each side, which, from the site of the plantations, does 
not generally occur. But the following analyses express 
the yields of the bark taken respectively from the north 
and south sides of a tree which is equally exposed on all 
sides. The bark was taken 25th July, 1871. 
North Side. 
South Side. 
Total alkaloids. 
3'18 
3'80 
Quinine. 
0'62 
1'40 
Cinchonidine and cinchonine. 
2'56 
2'40 
17. As the sun has been on the north side of the tree 
for the last four months, the effect has been that the 
yield of alkaloids has been diminished O'68 per cent. 
This decrease apparently consists of quinine, which is 
commercially the most valuable of the alkaloids. This 
effect has been produced in spite of its being the most 
cloudy period of the year. 
