54 EPIDENDRUM VENOSUM. VEINED TREE-ORCHIS. 



C. Reynolds writes of the beautiful appearance it presents when 

 growing on magnolias in that State ; and in the first volume of 

 the " Botanical Gazette," Mr. A. P. Garber, referring to the 

 plants of Florida which attracted his attention when he first 

 visited Eastern Florida in February, notes among his particular 

 impressions this singular orchid then in fruit. 



Though found so recently in the United States it is not a new 

 species, for it was discovered in Mexico by Theodore Hartweg, 

 who was sent to that country about the year 1836 and 1837 by 

 the Royal Horticultural Society of London, to collect seeds and 

 roots of the most beautiful plants he could find there for cultiva- 

 tion in English gardens. Hartweg says he found it growing on 

 oak trees. In Florida it is reported as chiefly on magnolias ; 

 but it is worth noting that these plants are not parasites, deriv- 

 ing their sustenance from the living trees, but are only supported 

 on the branches, obtaining their chief nutrition through their 

 aerial roots, with perhaps a little aid from the dead bark of the 

 supporting tree. When, therefore, we find the same species of 

 orchid seeming to prefer one class of tree in one country as the 

 oak in Mexico, and the magnolia in Florida, the reason is to be 

 sought in the varying conditions of climate as regards light, 

 shade and moisture. The seeds of our tree orchis, as indeed 

 of all orchideous plants, are as fine as dust, and require nicely 

 balanced conditions to germinate. There must be just so much 

 moisture, just so much heat, and just so much shade, and these 

 requirements vary in many species. In some countries, and for 

 our species for instance, these exact conditions would be better 

 secured on the branch of a magnolia than on an oak, while in 

 others the oak would furnish them to better advantage. It is 

 also worthy of note in connection with orchid seed that the con- 

 ditions most favorable to germination are not those generally 

 the best for the growth and subsequent flowering of the orchid 

 plant, and these observations lead to some remarkable teleo- 

 logical conclusions. The litde dust-like seeds, floating in the air 

 till caught by some branch, would not germinate if the branch 



