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XXXIX. On the Treatment of the Dendrobia, Aerides, and 

 other parasitical Plants. In a Letter to the Secretary. By 

 the Hon. and Rev. William Herbert, D. C. L., F. H. S. 

 fc. 



Read, August 1, 1820. 



Dear Sir, 



I am informed by a friend at Calcutta, that he cultivated, 

 with great ease, all the Dendrobia, Aerides, and other para- 

 sitical plants, by tying them, with twine, to the stem of a 

 tree, or to the under side of a branch, and placing above 

 them a pot of water, with a hole at the bottom, through which 

 a string passed, nearly as large as the aperture, by means of 

 which the water was gradually and continually conducted to 

 the upper part of the parasitical plant, which requires to be 

 constantly moist and shaded ; and that a tree with smooth 

 bark answered the purpose best. He mentions that Den- 

 drobium Pierardii, fastened to a tree and irrigated in this 

 manner, will, in a little more than a year's time, produce 

 pendulous racemes of flowers, from two to six feet long, and 

 it appears likely to thrive with me under the same treatment. 

 I had previously found no difficulty in establishing Epiden- 

 dra on the stems of trees in the stove, by cutting a notch in 

 the bark and inserting the plant like a graft, and tying moss 

 about it to support it, till the young roots had attached them- 

 selves to the bark ; but from want of sufficient moisture, they 

 have not made much progress, or flowered with me. I have 



