58 Proceedings of the Biological Society of Washington. 



its being endemic there. Its occurrence in Jamaica, Barbados and Guiana 

 previous to 1769 as well as its present wide dispersal in the American 

 tropics, suggest strongly that it is also native to the New World, though 

 it is possible that it may have been intentionally introduced by man. 



If we may rely on the testimony of Husbands, of Browne and of Ban- 

 croft, that the negro slaves used the plant medicinally, this may have 

 been sufficient incentive for them not only to bring it from Africa but to 

 carry it wherever they went in the American tropics. However, there is 

 no evidence that the negroes in Africa did or do use the plant in a 

 medicinal way. If such is the case no mention is made of the fact in 

 numerous books of African botany and travel examined. 



On the other hand, the plant was well known and long used medicinally 

 by the natives of India, it being mentioned according to Watt (Diet. Ec. 

 Prod. India. 5:286) in ancient Sanskrit works as an aphrodisiac, but its 

 use as an anthelmintic was introduced in comparatively recent years. 



Roxburgh (Flora Indica 3:283. 1832) however writes: 



"Annual, twining. Racemes pendulous. Legumes armed with sting- 

 ing hairs. 



" Dolichos pruriens, Linn. Supp. 657. &c. 



" Naicorana. Rheede. Mai. viii. t. 35. 

 ' Teling.— Doola gonda. Sans.— Murkuti. Atma goopta ro 

 ' Kupikuchoo. Beng.— Alkooschee. 



"Common in hedges, in most parts of India. Flowering time the cold 

 season. (I have never been able to learn that the natives of these parts 

 of India, make any use of any part of this plant, except the hairs of the 

 legumes which they do not use as a medicine, (vermifuge) but as an 

 ingredient to help to poison wells. However its having been of late taken 

 inwardly to destroy worms, proves that it is not that poison they take it 

 for; and it is more than likely that the other plants employed for the 

 same base end, are fortunately much less dangerous than those who em- 

 ploy them imagine. Indeed it is only the most ignorant superstitious 

 Poligar Mountaineers who are known to attempt to poison water.") . 



Ainslee (Materia Medica 1:93. 1826), Bentley and Trimen (Medicinal 

 Plants 2:78), and Watt (Diet. Ec. Prod. India 5:286) all assert that the 

 natives of India eat the young, tender pods. This seems very question- 

 able, but several closely related cultivated species which lack the stinging 

 hairs on the pods are thus eaten. These cultivated plants have by sev- 

 eral botanists been considered to be only varieties of the cowhage. 



The alternative supposition, namely, that the plant is native to the 

 tropics of both hemispheres, remains. Engler (Engler, Adolph. Sit- 

 zungsberichte der Preussichen Academie der Wissenschaften zu Berlin 

 1905, 1:180-231) has discussed at length the plants that occur in the 

 tropics of both the Old and New Worlds. Some of these plants, like the 

 cowhage, have their close relatives only in the other hemisphere. 



The list of plants common to the tropical America and Africa is a long 

 one, and after excluding all species that may have been transported by 

 ships, by ocean currents, by birds or by winds, there remain many for 

 which none of these explanations can be accepted. The most satisfactory 

 theory to Engler that will account for the facts is that there were for- 



