1837.] 



Dr. Wallich on Cassia Lanceolala, 



355 



been futind to answer best is to transplant the seedlings after they have 

 acquired a height of about 6 inches, at a distance from each other 

 of 3 feet, in slightly raised beds or patches of open ground, previously 

 well cleansed from weeds and enriched by the addition of some vegeta« 

 ble mould. We sow the seeds in the month of November ; germination 

 commences in about twelve days, and the transplanting takes place in 

 February ; after which the plants grow luxuriantly, provided they are 

 watered during the hottest days of April and May. Upon the whole, it 

 has been found, that shading of any kind does more harm than good ; 

 and although a number of the young plants perish in their tender age 

 from the excessive heat, yet by constantly supplying their place 

 with fresh seedlings no sensible loss has occurred in the end from that 

 source. The plants begin to blossom in April, and they continue pro- 

 ducing successive crops of flowers and fruit until the cold weather 

 begins to make its first appearance early in October, soon after which 

 the plants die away ; very few individuals surviving a second year. 



Mr. Twining having with his accustomed liberality undertaken to 

 ascertain the quality of the Senna leaf produced this year at the Botanic 

 Garden, I am enabled to annex his very satisfactory report to this paper. 

 It is proper, however, to observe, that the leaves furnished to that 

 gentleman were gathered during the rainy season, in the months of 

 July and August, — probably the most unfavourable of all for securing 

 their active principle pure and undiluted, not only because the sap of 

 the plant is then at its fullest rise, and necessarily modified by the con- 

 tinued production of flowers and fruits, but also because the drying of 

 the leaf without the aid of artificial heat (as has been the case in the 

 present instance), is a matter of doubtful effect. I am, therefore, war- 

 ranted in saying, that had the leaves been collected in the dry weather, 

 as I will take care they shall be next year, they would probably have 

 proved superior to the Senna procurable in the Calcutta bazar. 



Some explanation may perhaps be necessary for my offering a detailed 

 description and coloured figure of a plant, which is already known 

 to the world, in both respects, chiefly by the labours of De Lile in the 

 superb French work on Egypt. But independent of the account 

 there given being necessarily short and succinct, although illustrated by 

 a most beautiful engraving, the work itself is so very expensive and 

 scarce in this country (I believe it does not exist any where except in 

 the Library of the Asiatic Society of Calcutta, at least on this side of 

 India) that few only can have access to it. I have had the advantage of 

 examining the plant leisurely in its various stages ; and as my object is 

 to furnish the Medical profession in India with the means of identify- 

 ing a plant yielding one of the most extensively useful articles of 

 Materia Medica, I trust I shall be excused even if I had nothing to oiler 

 but what had been furnished already from other sources. 



