us - CONVOLVULACEiE. 



SEMEN KALADAN^. 



r 



Semen Pharbitidis ; Kaladcm a. 



Botanical Origin — Lpomcea NW^ Eoth (Pharhitls Fil Choisy, 

 Convolvulus Nil L.), a hvining annual plant, with a large blue corolla, 

 much resembling the Major Convolvulus (Pharbitis hispida Choisy) of 

 Endish o-ardens, but haviriPf three-lobed leaves.^ It is found throughout 



the tropical regions of both hemispheres, and is common in Inrlia, 

 ascendinof the mountains to a heio'ht of 5000 feet. 



History — The seeds of this plant were employed in medicine by the 

 Aral>ian physicians under the name Habbun-nil ; and they have pro- 

 bably been long in use among the natives of Hindustan. In recent 

 times they have been recommended by O'Shaughnessy, Kirkpatrick, 

 Bidie, Waring^ and many other European practitioners in India as 

 a safe and efficient cathartic. 



Description— The shape of the seeds is that which would result if 

 a nearly spherical body were divided perpendicularly around its axis 

 into G or 8 almost equal segments, only that the back is less regularly 

 vaulted. The seeds are I of an inch high and nearly as much broad ; 

 100 of them weio-h on an averac^e about G irrammes. There is a smaller 



^.. „„ ™. ^ . v^^^^v. u,,^^^^ ^ ^ 



variety imported from Calcutta, of which 100 seeds weio-h but little over 

 3 grammes ; in every other respect the two sorts are identical. Both 

 are of a dull black, excepting at the umbilicus, which is brown and 

 somewhat hairy. The adjacent parts of the thin shell (testa) crack m 

 various directions, if the seed is kept for a short time in cold Avater. It 

 it is removed from the upper part of the vaulted back, the radicle be- 

 comes visible, surrounded by the undulated folds of the cotyledons, 

 which join perpendicularly, but cannot be easily unfolded by reason ot 

 the thin seminal integument. Cut transversely, the cotyledons sll0^v 

 the same curled structure. Throughout their tissue, small bnght 

 glands in considerable number are observable, even without a lens. 

 The kernel, which is devoid of albumen, has at first a nutty taste, with 

 subsequently a disagreeable persistent acridity. When bruised in a 

 mortar, the seeds evolve a heavy earthy smell. 



Microscopic Structure— The seed is covered with a dark bla 

 cuticle, formed of a densely packed tissue, the cells of ^vhich show 

 zigzag outhnes. The dark brown epidermis is composed of very close 

 cylindrical cells, about 70 mkm. in length and 5 to 7 mkm. in diameter , 

 they require to be treated with chromic acid in order that their structure 

 may be distinctly seen. 



The tissue of the kernels is made up of thick-walled cells. Between 

 this tissue and the shell there is a colourless layer, about 70 mi^^}'^_ 

 thick, of thin- walled corky parenchyme. The cotyledons contain m 

 their narrow tissue numerous granules of albuminous matter, mucilage, 

 a httle tannic acid, crystals of oxalate of calcium, and a few starci 

 granules. The glands or hollows, before alluded to as occurring througn 



Kcda-dana, black seed. />/,„,/= part 22 (1877). 



3 Pharm. Journ. vii. (1866) 496. 



