March i, 1883.] 



THE TROPICAL AGRICULTURIST. 



70s 



Pitayo bark is largely exported from Buenaventura in 

 the Bay of Cliooo, farther north. 



Payta, the most northerly port of Peru, and C.illao, 

 the port of Lima, likewise export bark, the latter being 

 the natural outlet for the barka of Central Feni, from 

 Huanuco to Cuboo. Islay, and more particularly Anca, 

 receive the valuable barks of Carabaya and of thn high 

 valleys of Bolivia. Among other porta may be mentioned 

 Santa Marta, Savanilla and Maracaibo. 



Our imports for 18SI and 1880 were thus made up :— 

 1881. 1880. 



Calisaya . . 7,020 6,580 serous and eases. 



Soft Colom- ) 



oTa-na^ 87,200' 44,500 „ „ bales. 

 Pitayo. ) 



1881. 1880. 



Carthagena . 6,720 6,480 aerons and bales. 



^a^nd Ceylon ( ^^'*°° '^^'^^^ •• cases and ballots 

 The receipts in America, mainly direct from Colombia 

 »ad New Granada, were as follows : — 



1881. 1880. 



31,400 32, 800 serons and packages. 

 Tlie imports into France were also thus made up : — 

 1881. 1880. 



Calisaya „ ,, 9,915 8,590 packages. 



Colombian, etc. 16,550 11,580 ,, 



From the above tables it is noticeable that the richer 

 barks still continue to be consigned to England. 



Of the barks used in pharmacy, as before stated, 

 four in number are official in the British Pharma- 

 copceia. Of these, C. officinalis, C. succiriibra and C. 

 Calisaya are the sources from which the pharma- 

 ceutical preparations are directed to be made, whilp 

 C. lancifolia is alluded to as a source of quinine. 

 _ The following is a brief description of the dis- 

 tingiiishing characters of these important barks : — 



Cinchona Officinalis, Pale Cinchona, Loxa or Crown 

 Bark (Cortex Cinchona'. Pallidie). — This species is a 

 native of Ecuador and Peru, existing under several 

 varieties. If forms a large treo having lanceolate leaves 

 usually pointed, glabrous and shining on the upper 

 surface. The flowers are small, pubescent, and in 

 short ijanicles and are succeeded by oblong or lan- 

 ceolate capsules, 4 an inch or more in length. The 

 bark yielded by this tree, which formerly was the 

 ordinary Peruvian bark of English medicine, is only 

 found in the form of quills, which are occasionally as 

 much as a foot in length, but more often in fi'ag- 

 ments of a few inches. The quills are from S to J 

 of an inch in diameter, having a blackish-brown or 

 dark grey external surface, variously blotched with 

 silver grey, and frequently covered with large and 

 beautiful lichens. The surface of some of the quills 

 is longitudinally wrinkled and moderately smooth, 

 but in the majority it is distinctly marked by trans- 

 verse cracks. The inner side is closely striated and 

 of a bright yellowish brown. 



The baik breaks easily with a fracture which ex- 

 hibits very short fibres on the inner fcide. Though 

 chiefly aftbrded by Cinchona officinalis, other species 

 occasionally contribute to furnish the Loxa bark of 

 oominerce, as shown in the table above. Owing, 

 howevtr, to the bark having become nearly extinct 

 in its native regions, at the present day it is .scarcely 

 possible to obtain genuine Loxa or crown bark from 

 South America ; the immense plantations on the 

 Nilgiri Hills of Madras, in the Sikkim Himalayas 

 and elsewhere in India, Ceylon, and Jamaica, are at 

 present the chief sources of tho bark in commerce. 

 The analyses of Howard .sh"W that the different 

 varieties of crown bark vary much in the proportion 

 of alkaloids they contain, South American bark yield- 



ing on an average "5 to 1 per cent, of alkaloids, 

 while the Indian bark yields as much as 4-30 to 6 

 per cent., consisting principally of quinine, and next 

 in order cinchonidine and cinchonine. I might also 

 be noticed here that the (.fficial pale bark of the 

 United States Pharmacopoeia also includes the kind 

 of bark which is derived from Cinchona micranlha, 

 a bark which was formerly olficial in the Edinburg 

 and Dublin Pharmacopoeias under the name of Cin- 

 chona cinerea, and which is known to commerce a8 

 grey or Huanuco bark. 



Cinchona Succirubra, Hcd Bark {Cortex Cmchonce 

 Rubrw.)— The tree yielding this species, although 

 formerly growing in all the valleys of the Andes, is 

 now almost entirely confined to the forests of Gu'ar- 

 anda on the western declivities of Chimborazo, at 

 2000 to 5000 feet above the level of the sea. The 

 tree has broadly ovate leaves attaining about a foot 

 in length, nearly glabrous above, pubescent beneath 

 and large terminal panicles of rose-coloured flowers, 

 succeeded by capsules from 1 to IJ inch lou{.'. Red 

 cinchona bark occurs in quills and flat pieces. The 

 quills vary in diameter from J to 1| inch, and 

 in length from 4 to 12 inches or more. Tho so-called 

 flat pieces are frequently slightly incurved, from 1 

 to 5 inches broad, | of an inoli in thickness and 

 about 2 feet in length. Red cinchona bark is gener- 

 ally coated and consists of liber, the cellular and 

 tuberous coats, and usually more or less of the 

 epidermis ; its outer surface is rongh, furrowed and 

 frequently warty. The colour of the epidermis varies; 

 in the thinner quills it is reddish-brown; in thick 

 quills and flat pieces it varies from a reddish-brown 

 to a chestnut-brown, frequently with a purplish tinge. 

 Cryptogamio plants are not so frequent on ihis as on 

 some other kinds of bark. Tho cellular coat of the 

 flat pieces ia very thick and spongy, much more so than 

 in vellow cinchona bark. The inner surface of the quills 

 is finely fibrous, giving a comparatively smooth fracture 

 while the fracture of the flat pieces is both fibrous and 

 splintery. As to the proportion of alkaloids in red 

 bark, the thick flat sort contains only 3 to 4 per cent, 

 of alkaloids, but a large amount of red colouring matter! 

 In referrenca to the brick-red colouring matter which, 

 as Ruiz observes, is not found in the growing plant, 

 but in the dried bark, Mr. J. E. Howard considers 

 that it is really an excretory product of vegetation, 

 a part used up and brought by coniaot with the air 

 into a state in which it can no longer be serviceable 

 to the living plants, and from which it still degener- 

 at»3 by a still further degeneration into humus. 

 The pieces of flat red bark possessing the finest colour 

 are generally remarkable for their speoifio ligbtnesi, 

 having a texture analogous to that of wood that has 

 lost its firmness by incipient decay. Indeed, it is by 

 a process of iremacausis that the red bark aquirca its 

 colour, tlie cinchotannic acid in which it abouuds hav- 

 ing become oxidized and changed into cinchona red, 

 and under these conditions the alkaloids also appear 

 to undergo a .me corresponding alterations. They are 

 now implicated with resin, which appears to have also 

 become oxidized so as to act the part of an acid, and 

 is with diflieulty separated. But the most remarkable 

 feature is the altered conditinn of the alkaloids them- 

 selves. Quinine, which formed a considerable portion 

 of the whole, is now greatly diminished, while cin- 

 chonine and cinchonidine remain much i he same. The 

 quill red bark of the Indian plantations is a niuoh 

 better drug, some of it yielding 5 to 10 per cent, of 

 alkaloids, less than a third of which is quinine and » 

 fturth cinchonidine, the remainder being cinchonine 

 and sometimes traces of quinidine. 



Tho experiments of Mr. J. E. Hi. ward and oihers 

 have also proved that the bark of the root contain* 

 a larger proportion of alkaloids than that of the sttm; 



