Vol. X. No. 235. 



THE AGRICULTURAL NEWS. 



139 



THE BENGAL BEAN. 



Work ha.s been undertaken recently by Messrs. C. V. Piper 

 and S. M. Tracey, of the United States Department of Agri- 

 culture, having for its object the determination of the true 

 botanical relationships of various plants which were considered 

 to belong to the genus Mucuna. The purpose of the investi- 

 gations was to find plants closely related t'j the Florida vel- 

 vet bean which would attain maturity earlier, and be thus 

 more suited to conditions in the Southern States. The 

 receipt of seeds of plants resembling the Florida velvet bean, 

 growing in Brazil and the Philippins Islatids, made it seem 

 expedient to try to collect plants of all the other .species of 

 the genus Mucuna, in order to find varieties that would reach 

 maturity more quickly, or prove more valuable, than the 

 Florida velvet bean. Previously, this plant had been shown 

 to belong to the genus Stizolobium, and not to Mucuna, and 

 had been named Stizolobium deerinffianum. The result of 

 the work of the investigators mentioned has been to show 

 that at least twenty distinct plants that were once regarded 

 as species of Mucuna are included in the genus Stizolobium. 

 Further, a matter of practical interest has been demonstrated; 

 namely, that these plants show greater possibilities of u.seful- 

 ness than have been attributed to them, so far. 



The work of the investigators mentioned is published in 

 Bulletin No. 179 of the Bureau of Plant Industry of the 

 United States Dejiartment of Agriculture. The purpose of 

 the present article is to .show how the results of this work 

 have reference to the Bengal or Mauritius bean, which has 

 been generally described as Mucuna iitilis, or Miicuna 

 pruriens, var. vtilis. Specimens of this bean were sent from 

 Barbados some time ago, and were identified with others as 

 belonging to a new species called Stisololiiiua aterriiaum. 

 More recently, specimens of the Bengal bean, from Mont- 

 serrat, have been sent b}' this Department to Kew for identifi- 

 cation, in order that there may be no doubt as to the true 

 affinities of the plant called Bengal bean in that island. 

 A reply has been received to the elfect that this bean, like 

 the one known by the same name in Barbados, belongs to the 

 species Stizolohinra nterrimiim. The description of it, as 

 given by Piper and Tracy is as follows: — 



' Vine very strong and vigorous, the stem striate but 

 scarcely furrowed, covered with a soft, sparse pubescence; 

 leaflets very large, plane, mostly acute, strongly mucronate, 

 sparsely appressedpubescent on each side; racemes pendant, 

 18 to 30 inches long, many flowered; flowers purple; calyx 

 not saccate, densely appressedpubescent without and within; 

 pods falcate, about 4 inches long, black when mature, sparsely 

 covered with a short, white, appressed pubescence; median 

 ridge on valve prominent but sometimes liroken; secondary 

 ridge faint or wanting; seeds four or five, oblong, black, very 

 shiny, 10 to 12 mm. long, the prominent hilum white.' 



The reason why the plant has been known as Mucuna 

 utilis is that Voigt gave an identification of this, under 

 a description of this species by Wallich. The identification 

 is considered by Piper and Tracey to be erroneous; though 

 there is some doubt in the matter until comparison can be 

 made with the original type. The authors mentioned state 

 that .S'. aterrimum appears to be more widely cultivated than 

 any of the other Stizolobiums, as they have received speci- 

 mens from Au.stralia, Cochin-China, Mauritius, Java and 

 ■Ceylon, in addition to those already mentioned from Brazil 

 and Barbados. The plant is grown in Hawaii under the name 

 Mauritius bean; a name for it in Brazil is the horseeye bean. 

 Further, evidence is given in the bulletin mentioned to show 

 that the habit of the plant varies to some extent in different 

 parts of the world. 



As a re.sult of the investigations, the Bengal liean is to 

 be known as Stiwlohium aterrimtita, and the Florida velvet 

 bean as S. deeringianum. In addition, the cowitch, or cow- 

 hage, will be called .9. pruriens, and the Lyon bean, or 

 Sabiial, from the Philippines, S. niveuvf. 



MASOARENHASIA RUBBER. 



The Bulletin of the Imperial. Institute, Vol. VIII, 

 Xo. 4, pnbii.shed recently, gives information concerning 

 the rubber oi Mascarenhasia elastica — a plant found in 

 East Africa and Madagascar — as follows: — 



In 1898 a new rubber-yielding tree was discovered by 

 Dr. Stuhlmann in the neighbourhood of Dar-es-Salaam, Ger- 

 man East Africa, and from the botanical specimens which he 

 collected, the plant was determined by Dr. K. Schumann as 

 a new species of Mascarenhasia to which the name Mascaren- 

 hasia ela^tica was given. The plant was descrilied as a small 

 tree, from 30 to 40 feet in height, with slender branches; the 

 trunk usually branches low down and is covered with a grey- 

 ish bark. The leaves are oppo.site, oblong obtuse or obtusely 

 and shortly acuminate, acute at the ba.se, and coriaceous; they 

 vary from 3 to 10 inches long and from IJ to 2^^ inches broad. 

 The flowers are conspicuous and fragrant; the follicles are 

 purplish-black and from 3 to 3i inches long. 



Like other species of the genus, Mascarenhasia elastica 

 furnishes rubber which is collected to some extent by the 

 natives, and is known as M'goa or Goa rubber in East Africa. 

 It is stated, however, that the latex flows so slowly that the 

 collection of the rubber is not profitable, and that owing to 

 the crude methods employed, the product is of inferior quality 

 and low value. 



Mascarenhasia elastica is reported to be fairly common in 

 the neighbourhood of Dar-es-Salaam, growing principally on 

 the banks of streams or in moist situations. The trees have 

 smooth, straight trunks, which are u.sed by the natives for 

 building their houses, and it is for this purpose, rather than 

 as a source of rubber, that they are chiefly prized. 



Experiments which have been made in German East 

 Africa on the cultivation of the tree have shown that it grows 

 quickly even in dry soil, and flowers and fruits when five years 

 old. The yield of latex at this stage was, however, only 

 slight. For some years after its discovery in German East 

 Africa, Mascarenhasia elastica was not recorded from any 

 other locality, but it has since been found in the East Africa 

 Protectorate, the island of Pemlia, and Portuguese East Africa, 

 and specimens of the rubber furnished by the tree in these 

 countries have been examined at the Imperial Institute. 



After giving the results of the examination oi 

 different samples from the East Africa Protectorate, 

 Pemba, and Portuguese East Africa, the article presents 

 the following conclusions: — 



The results of the examination of these specimens of 

 Mascarenhasia elastica rubber from the East Africa Protector- 

 ate, Pemba, and Portuguese East Africa, show that the pro- 

 duct is of good quality if carefully collected. No definite 

 information is, however, available regarding the average yield 

 of rubber which the trees will furnish, so that it is not possible 

 at present to state the probable value of the plant as a source 

 of rubber. The experiments which are in progress in all 

 three countries will determine this point, and also the further 

 question of the suitability of this East African rubber tree 

 for cultivation in suitable localities. 



