Quinamina, or quinamine, having the composition C20H24N2O2.
Besides the above, an alkaloid, which has been named Paracina, has been obtained from the bark of the Cinchona succirubra; whilst in those barks which contain only small portions of the more active constituents above named there have been found two alkaloids, named respectively Aricia and Cusconia, which have lately been accurately investigated by Hesse, who has determined their chemical constitution (Liebig’s ‘Annalen und Berichte der Chemische Gesselschaft in Berlin’).
The following Prospectus of the principal Species of Cinchona is from Flückiger and Hanbury’s ‘Pharmacographia,’
| Species (excluding Sub-species and Varieties) according to Weddell. | Where figured. | Native Country. | Where cultivated. | Product - Cinchona Barks. |
| I. Stirps Cinchonæ officinalis— | ||||
| 1. Cinchona officinalis, Hook. | ‘Bot. Mag.,’ 5364 | Ecuador Loxe, Peru | India, Ceylon, Java | Loxa, or Crown Bark, Pale Bark. |
| 2. Cinchona macrocalyx, Pav. | Howard, ‘N. Q.’ | Peru | — | Ashy Crown Bark. The sub-speciesC. Palton affords an important sort called Palton Bark, much used in the manufacture of quinine. |
| 3. Cinchona lucumæfolia, Pav. | Howard, ‘N. Q.’ | Ecuador, Peru | — | Carthagena Bark, confounded with Palton Bark, but is not so good. |
| 4. Cinchona lanciolata, R. and P. | Howard, ‘N. Q.’ | Peru | — | Columbian Bark. Imported in immense quantities for manufacture of quinine. The soft Columbian Bark is produced by Howard’s var. oblonga. |
| 5. Cinchona lancifolia, Mutis. | Karst., tab. 11, 12 | New Granada | India | Ditto. |
| 6. Cinchona amygdalifolia, Wedd. | Wedd., tab. 6 | Peru, Bolivia | — | A poor bark, not now imported. |
| II. Stirps Cinchonæ Rugosæ— | ||||
| 7. Cinchona Pityrensis, Wedd. | Karst., tab. 22 (G). Triane | New Grenada, Popayan | India | Pitayo Bark. Very valuable; used by makers of quinine. It is the chief source of quinidine. |
| 8. Cinchona rugosa, Pav. | Howard, ‘N. Q.’ | Peru | — | Bark unknown, probably valueless. |
| 9. Cinchona Mutisii, Lamb. | Howard, ‘N. Q.’ | Ecuador | — | Bark, not in commerce, contains only aricine. |
| 10. Cinchona hirsuta, R. and P. | Wedd., tab. 21 | Peru | — | |
| 11. Cinchona Carabayensis, Wedd. | Wedd., tab. 19 | Peru, Bolivia | — | Bark, not collected. |
| 12. Cinchona panudiana, How. | Howard, ‘N. Q.’ | Peru | India, Java | A poor bark, yet of handsome appearance; propagation of tree discontinued. |
| 13. Cinchona asperfolia, Wedd. | Wedd., tab. 20 | Bolivia | — | Bark not collected. |
| 14. Cinchona umbelluliferæ, Pav. | Howard, ‘N. Q.’ | Peru | — | Bark not known as a distinct sort. |
| 15. Cinchona glandulifera, R. and P. | Howard, ‘N. Q.’ | Peru | — | Bark not known as a distinct sort. |
| 16. Cinchona Humboldtiana, Lamb. | Howard, ‘N. Q.’ | Peru | — | False Loxa Bark, Jaen Bark. A very bad bark. |
| III. Stirps Cinchonæ Micranthæ— | ||||
| 17. Cinchona Australis, Wedd. | Wedd., tab. 8 | South Bolivia | — | An inferior bark, mixed with Calisaya. |
| 18. Cinchona scrobiculata, H. and B. | Wedd., tab. 8 | Peru | — | Bark formerly known as Red Cusco Bark or Santa Anna Bark. |
| 19. Cinchona Peruviana, How. | Howard, ‘N. Q.’ | Peru | India | |
| 20. Cinchona nitida, R. and P. | Howard, ‘N. Q.’ | Peru | India | Grey Bark, Huanuco, or Lima Bark. |
| 21. Cinchona micrantha, R. and P. | Howard, ‘N. Q.’ | Peru | India | Chiefly consumed on the Continent. |
| IV. Stirps Cinchonæ Calisayæ— | ||||
| 22. Cinchona Calisaya, Wedd. | Wedd., tab. 9 | Peru, Bolivia | India, Ceylon, Java, Jamaica, Mexico | Calisaya Bark, Bolivian Bark, Yellow Bark. The tree exists under many varieties; bark also very variable. |
| 23. Cinchona | elliptica, Wedd., tab. 9 | Peru, Carabaya | — | Carabaya Bark. Bark scarcely now imported. C. cuneura, Miq. (flower and fruit unknown), may perhaps be this species. |
| V. Stirps Cinchonæ ovatæ— | ||||
| 24. Cinchona purpurea, R. and P. | Howard, ‘N. Q.’ | Peru, Huamalies | — | Huamalies Bark, not now imported. |
| 25. Cinchona rufinervis, Wedd. | Howard, ‘N. Q.’ | Peru, Bolivia | — | Bark a kind of light Calisaya. |
| 26. Cinchona succirubra, Pav. | — | Ecuador | India, Ceylon, Java, Jamaica | Red Bark; largely cultivated in British India. |
| 27. Cinchona ovata, R. and P. | Howard, ‘N. Q.’ | Peru, Bolivia | India (?), Java (?). | Inferior brown and grey barks. |
| 28. Cinchona cordifolia, Mutis. | Karst., tab. 8 | New Granada, Peru | — | Columbian Bark (in part). Tree exists under many varieties; bark of some used in manufacture of quinine. |
| 29. Cinchona Tucujensis, Karst. | Karst., tab. 9 | Venezuela | — | Maracaibo Bark. |
| 30. Cinchona pubescens, Vahl. | Wedd., tab. 16 | Ecuador, Peru, Bolivia | — | Areca Bark (Cusco Bark from var. Pelletieriana). Some of the varieties contain aricine. C. caloptera, Miq., is probably a variety of the species. |
| 31. Cinchona purpurascens, Wedd. | Wedd., tab. 18 | Bolivia | — | Bark unknown in commerce. |
The cinchona barks vary greatly in the amount of alkaloids they contain and in their proportion to each other, these being dependent upon the species or varieties, and many other circumstances. Of the alkaloids, quinia and cinchonia were till lately the most abundant, but since the introduction of cinchona cultivation into India, cinchonidia has been found in very large quantity. Royle says:—“Good Calisaya bark usually contains from 5 to 6 per cent. of quinia,” but actually South American calisaya containing such an amount of quinia is rare in the market. Some barks, however, derived from cinchonas cultivated in India, such as C. Calisaya, var. Ledgeriana, and some varieties of C. officinalis, yield even a still higher per-centage of quinine.
The South American crown, or loxa bark, is very variable, and contains chiefly cinchonia.
Red bark also varies considerably, yielding from 3 to 10 per cent. of alkaloids, of which quinia forms only a small fraction, whilst generally cinchonidia is predominant. The development of the alkaloids is greatly influenced by cultivation, but particularly by the “renewing process,” which, applied to the C. succirubra, trebles the amount of quinine in the bark.
In addition to the alkaloids already mentioned, the cinchona barks contain the following acid principles:—Kinic acid, Cincho-tannic acid, and Quinovic or Chinovic acid. The quinovic acid is accompanied by an amorphous bitter substance, named Chinovin or Quinovia, which is present in much greater proportion than the acid, of which generally there are only traces. A description of these bodies will be found by referring to them under their respective names. Cinchona-red is another amorphous substance which is the body to which the red hue of the cinchona barks is due. It is produced when cincho-tannic acid is boiled with dilute sulphuric acid, sugar being formed at the same time.
When fused with potash, proto-catechinic acid is formed. Cinchona red dissolves sparingly in alcohol, freely in alkaline solutions, but neither in water nor ether. Thick red bark contains it to the amount of more than 10 per cent.
Cinchona red is the product of the oxidation of cincho-tannic acid, and is contained largely in South American red bark, because this is the product of old trees; but sparingly in Indian red bark, because this is always collected from trees not more than fourteen years old.