October t, 1885.] THE TROPICAL AGRICULTURIST. 



301 



leaves, so as to make a long funuel which is wide at 

 the mouth and narrowed to almost a point at the 

 base. Over the mouth the flap-like lid is fixed aud 

 in some of the species stands erect so as to admit 

 rain-water into the pitchers, whilst in others the lid 

 curves over in such a mnmier as to hinder the rain 

 from falling into them. In 1815, the then President 

 of the Linnean Society. Dr. James McBride, read a 

 communication on the fly-catching propensity of Sarra- 

 cenias, from which the following is worth quoting, as 

 it describes accurately what we have repeatedly observed 

 in the collection of Sarracenias cultivated at Kew. 

 He says, writing chiefly about t^airacenia vufiolaris: 

 " If, in the months of May, June, or July, when 

 the leaves of these plants perform their extraordinary 

 fimctions in the greatest perfection, some of them 

 should be removed to a house and (ixed in an erect 

 position, it will soon be perceived that flies are attract- 

 ed by them. These insects immediately approach the 

 fauces of the leaves, and, leaning over their edges, 

 appear to sip with eagerness something from their 

 internal surface. In this position they linger, but 

 at length allured, as it would seem by the pleasures 

 of taste, they enter the tubes. The fly, which has 

 thus changed its situation, will be seen to stand un- 

 steadily, it totters for a few seconds, slips, and falls 

 to the bottom of the tube, where it is either drowned 

 or attempts in vain to ascend against the points of 

 the hairs. The tly seldom takes wing in its fall and 

 e.scapes. In a house much infested with flies this 

 entrapment goes on so rapidly that a tube is filled 

 within a few hours, and it becomes necessary to add 

 water, the natural quantity being insufficienfto drown 

 the imprisoned insects. The leaves of other species 

 might well be employed as fly-catchers ; indeed I am 

 credibly informed that they are in some neighbour- 

 hoods. The leaves of Surracrnia Jiara, although they 

 are very capacious, and often grow to a height of 

 three feet or more, are never found to contain so 

 many insects as those of other species. The cause 

 which attracts flies is evidently a sweet viscid sub- 

 stance resembling honey, secreted by, or exuding from, 

 the internal surface of the tube. From the margin, 

 where it commences, it dors not extend lower than 

 one-forth of an inch. The falling of the insect as 

 soon as it enters the tube is wholly attributable to 

 the downward or inverted position of the hairs of 

 the internal surface of the leaf. At the bottom of a 

 tube, split open, the hairs are plainly discernible jjoint- 

 irg downwards ; as the eye ranges upwards they 

 gradually become shorter and attenuated, till at, or 

 just below, the surface covered by the bait, they are 

 no longer perceptible to the naked eye nor to the 

 most delicate touch. It is here that the fly cannot 

 take a hold suflaciently strong to support itself, but 

 falls. The inability of insects to crawl up against the 

 poiuts of the hairs I h.ave often tested in the most 

 satisfactory m->.nner" (Trtin^. lyinncan Society, vol. 

 xii.). I have again and again released blue-bottle flies 

 after they have been trapped, and have never yet found 

 them act in any way that would suggest sn intoxic- 

 ating property in the secretion which they had fed 

 upon— this is contrary to the iuformntiou of " AV. 0. M.," 

 who says:— "After feedii-.p upon the secretion for two 

 or three minutes, they [the infects] become quite 

 Btupid, unsteady on thtir feet, kc." To prevent the 

 pitchers being injured by (he large number of insects 

 Which are lured into them, we find it nrccsary at 

 Kcw to 611 (he mouths nf the pi'fhirs with cotton, 

 wool; this p cvcids tie inseits f oin falling in. Be- 

 fore this precaution was taken mAuy of our finest 

 pitchers were lost, owing to the decay which was caused 

 by the rotten mass of insects which had accumul- 

 ated in the bottom of the pitchers. "\Y. 0. M." 

 will bo surprised to hear that, in .spite of this cutting 

 fcff of the supply of insects to the pitchers, tlie plants 

 were in no way affected as lejarded growth or vigour, 

 but that the length and gi-nt-ral health of the i)itchers 

 were more satisfaitory atter the insects were not 

 allowed to enter them, than before. The concluding 

 sentence in his remarks is rather startling, as, so far 

 H investigations conducted by pbysiologistt Jiave goue 



hitherto, the Sarraf?nias are not known to be carni- 

 vorous. Jlr. AV. H. Gilburt, of the Quekett Micro- 

 scop,...; Olub, says:— "The pitchers contain fluid, but 

 nothing corresponding to a digestive fluid has been 

 detected ni them; so that, .if the insects which perish 

 m the pitcher are of any value to the plant and 

 afford any nutriment, it must be simply by maceration, 

 and the glands can be regarded as "absorbent only." 

 Of course it may be s.iid that Sarracenias would not 

 havb been constructed with what appears to be a view 

 specially to catching insects, if the insects were not to 

 serve some usefid purpose in the economy of the 

 plant. Anyhow, at present it is only safe to say of 

 Sarracenias that they allure and ultimately destroy 

 insects, but we do not yet know that they obtain 

 nourishment from them. Certainly under cidtivation 

 there is_ abundance of evidence to prove that these, 

 aud in fact all those plants which are considered to 

 be distinctly carnivorous, grow and thrive at least as 

 well when insect food is not allowed them as when it is. 

 Kew. -\Y. -Watson. ' 



♦ 



CINCHONA NOTES. 

 About the time of the Franco-Prussiau war, when 

 scientilic observation was more or less paralysed over 

 the greater portiou of Europe, some seeds of Cinchona 

 ojpcinalis were sent by the late botanist, Decaisue, of 

 the Paris Jardin des Plantes, and by M. Moriu, to 'the 

 small French colony of Reunion, and were immediately 

 planted near the shore. 



The little shoots were soon afterwards transplanted 

 to the neighbouring hills, where they were set at an 

 altitude of about 2,500 feet above the level of the 

 oceau. For the next four years the plants were watched 

 with much anxiety. At the end of that time the ex- 

 periment was proved to he not only interesting but 

 practically successful; a cutting from one of the first 

 little plauts had then become a tree more than U yards 

 high. 



These cinchona plants at Keuuiou produced both 

 flowers and fertile fruit; and the bark, when submitted 

 to analysis, proved rich in alkaloids. As early as 1875 

 Dr. A'inson, a resident, had upon his own plantation in 

 the island no less than 300 cinchona trees, and his ex- 

 ample was soon followed by several other gentlemen 

 who possesfed laud in that district. It was in this way 

 that the culture of Cinchona officimdis in the island 

 of Keunion, which is said to be giving promise of be- 

 coming very profitable to the landowners, was set 

 about in the first instance. AVh»n the trees of the 

 original plantations were about eight years old, the bark 

 taken from them and analysed showed that so far the 

 attempt to introduce cinchona had proved a'l evident 

 success; 2 lb. of this bark yieleled 210 grains of eiuinine 

 and 7i grains of ciiichonine. 



It thus appears that the maritime climate of Ke'iniion 

 Ishind, aud, perhaps, its volcanic soil also are well 

 adapted to the cultivation of Cinchona ofxcinidi.i. It 

 is, p.-rhaps, needless to remark that among our British 

 pos.sessions are to be^ found a very considerable number 

 of islands which would show similar favourable con- 

 ditions, but where, up to the present time, no attempt 

 has been made to introduce the cinchona frees. 



AVhile we were all discussing, not long since, the 

 prospects of the cinchona plantations in Ceylon, to 

 which we shall refer presently, a letter appeared from 

 Dr. Sacc, written at Buenos Ayres, in which he treats 

 of the culture of the cinchona trees in Bolivia, and on 

 certain other chemical and pharmaceutical products of 

 that country. 



Many readers nlll call to n:ind that it was (he reck- 

 less miinnor in whicli the Bolivian trees were and 

 are still struck down in order to collect the bark 

 which c:iused it to be feared that in the course of a 

 comparatively short space of time the supply of cinchona 

 bark from South America would f:ill sliort of the 

 ilemaud; and finnlly, perhaps, cease altogether. It 

 was this circumetance which caused sncli strenuous 

 efforts to establish cinchona plantations in Java, India 

 Ceylon, Bourbon Island, &c.; so that at jnesent these 

 various districts are actually competing, more pr less 



