HORTICULTURAL JOURNAL. 205 



the arctic regions disappear, while in and toward the tropics they abound in 

 surprising numbers. In the temperate regions they are, for the most part, 

 terrestrial, growing in meadows and pastures, while within the tropics they 

 are chiefly parasitical, or rather epiphytal, growing upon the trunks and 

 branches of living trees and shrubs, and also upon the trunks of those that 

 have fallen. Some can hardly be said to have any fixed place of abode, 

 and are found forming large tufts, firmly knit together by their numerous 

 and tortuous roots, and suffering little from being thrown about as the pas- 

 sing kick of the traveler may send them. 



A great number of tropical Orchideous plants are found adhering to the 

 branches of trees in the most dense forests in an epiphytal manner, not 

 fixed paratisically by their roots to the bark of the trees that support them. 

 In such situations they are consequently shaded from direct light by the 

 leaves and branches which surround them : they are also placed in a moist 

 atmosphere and high temperature, ventilation and evaporation being almost 

 precluded. 



To the fructification of Orchideous plants it may be necessary to make 

 some allusion, inasmuch as it is still but imperfectly known ; and although 

 Mr. R. Brown, and a few others, seem to have the production of plants of 

 this order from seeds at their command, still the generality of cultivators 

 have failed in producing similar results, and not a few, otherwise intelligent 

 and accurate in t their botanical researches, deem the theory altogether 

 visionary. 



The singular plants which constitute this class are distinguished from all 

 others by the anomalous structure of their flowers. These do not, as is 

 usually the case, contain a certain number of stamens, surrounding a cen- 

 tral ovarium or style, but on the contrary, are furnished with a solitary, 

 fleshy, undivided process, round which the sepals radiate, and which supplies 

 the place of stamens and style. The nature of this process has been va- 

 riously explained ; the modern opinion is, that it is formed by the accretion 

 of the stamens and style into a single mass, and this opinion seems to be 

 confirmed by analysis and analogy. Omitting, therefore, a notice of such 

 theories respecting its nature as are opposed to that which is now received 

 as the most correct, it will suffice to explain a little in detail the opinion 

 which is adopted in this work. The central process, called the columna or 

 column, is understood to be formed by the filaments of three stamens sur- 

 rounding a style, and by mutual accretion firmly united with it, and with 

 each other, into a solid mass. Of these three stamens, it most frequently 

 happens that the two lateral are sterile, and not furnished with even the 



