VEGETATIVE STRUCTURE. 



49 



importations which, so far as I know, have not been affected in this 

 way by their changed conditions. — CmJum non aiiimum mutaverunf. 



Tlie botanist who has these flowers put upon liis study table is 

 rarely able to do more tlian offer more or less plausible suggestions 

 as to the causes that have produced them such as his knowledge 

 of the ways of life of plants in general may afford. But the 

 cultivator is in a very different position ; lie knows the circumstances 

 under which the plants have been grown, he has watched them, it 

 may be from infancy to maturity, he has regulated and controlled 

 their natural dispositions, given or withheld as it seemed best to him, 

 heat, air, light, water, pushed them on or rested them to suit his 

 convenience. It is to him, therefore, as to a practical physiologist, 

 that we must look for the determination of the why and the where- 

 fore of these formations. It is to the botanist that we must look for 

 the interpretation of their stnicture and for the indication of their 

 significance as regards the construction, the purpose, the descent, and 

 the filiation of the great order to which they belong. 



VEGETATIVE STRUCTURE. 



Although a considerable diversity of habit exists among epiphytal 

 orchidsj much of which has resulted from external circumstances as 

 climate, locality, environment in situ, and even from the nature of 

 the substratum, trees, rocks, etc., on which they grow in a wild 

 state, the vegetative organs, the stems, leaves and inflorescence, 

 whether considered conjointly or separately are reducible to a 

 comparatively few types, some of which are repeated in many genera 

 while others are more restricted. As a detailed description of their 

 vegetative organs is given under all the most horticulturally im- 

 portant genera, only some of the most obvious generalisations with 

 especial reference to the Tribes Epidendre.e, Vande.e and CYrRiPEDiE.E 

 are here noticed. 



The vegetative organs of orchids in their inorphological aspect have 

 been studied by Professor Pfitzer, of Heidelberg, who has publishetl 

 the result of his observations in an elaborate work entitled Grundzuya 

 einer vergleiche/iden Morphologie der Orchideen (Outlines of a comparative 

 Morphology of Orchids). In this work the author attempts to construct 

 a comparative classification of orchids from the characters afforded by 

 their vegetative organs. A large ninnber of species included in many 

 genera have been nn'nutely examined and compared, and their morpho- 

 logical characters accurately noted and described ; but as a far larger 



