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@ONVOLVULUS JALAPA. ORD. XIII. Campanacee. QA7 
which supports a single flower; this is large, bell-shaped, entire, pli- 
cated, externally of a reddish colour, but of a dark purple within ;* 
the-calyx consists of five oval leaves, these are concave, somewhat 
indented at their points, and of a pale green colour; the filaments 
are five, slender, short, and the anthere large, and-yellow; the style 
is shorter than the stamina; the stigma is tound, and the germen 
oval, It is a native of South America, and flowers in August and 
September.* The plant we have figured was introduced into the 
Royal garden at Kew in 1778, by Mons. Thouin, and under the 
direction of Mr. Aiton it acquired great vigour and luxuriance, ex- 
tending its stalks fifteen feet in length; and, by means of slips 
obtained from it, two healthy young plants have since been pro- 
duced: this circumstance is the more fortunate, as the parent plant 
lately died. Botanists have differed much respecting the officinal 
Jalap plant; Linnzus following Clusius, Plumier, Tournefort, and 
others, first referred it to the Mirabilis, but in the second edition 
of his Materia Medica he adopts the opinions of Ray and Miller, in 
considering it a Convolvulus; and indeed after the account of this 
plant given by Dr. Houston,” we are surprized that any doubt 
should still remain upon this subjuet.° 
It is said that the root of Jalap was first brought to Europe about 
* The colour will no doubt vary. This plant, at Kew, produced yellowish flowers; 
but the plants obtained by Houston from the Spanish West Indies answers to the 
description we have given, 
* Hort. Kew. * See Linnzus’s Observ. ia Mat. Med. 1772. p. = 
© The London College have not referred to the Linnzan name of this plant.— 
Bergius found that neither the dried root of the Mirabilis Jalapa, nor of the M. longi- 
flora, given in the dose of half a dram, produced any cathartic effects, but he says 
that of the M. dichotoma satis bene purgat; and as its root also bears some resem- 
blance to the true exotic jalap, he hence infers that it is the same. However, with 
great deference to the learned professor, we think these reasons insufficient to 
warrant his conclusion, more especially as they are repugnant to establish facts. 
We may also observe, that all the three species of the Mirabilis are in some degree 
purgative; but even when fostered in the warm climate of Jamaica, so congenial to 
their native soil, their roots, both in appearance and medicinal power, essentially 
differ from those of jalap. 
