430 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XVI. 



Orchitis are found in the greatest variety and profusion in tropical 

 and sub-tropical regions possessing a perennially moist atmosphere 

 accompanied by an absence of extreme cold at any season of the year. 

 In India the largest proportion of the order is found in the valleys and 

 plains of the North-eastern frontier and Burma. In the Bombay 

 Presidency the most suitable natural conditions prevail only in the 

 forests of Kanara and the Southern Konkan. Several epiphytic 

 species are found throughout the range of the Ghats and Konkan, but 

 they do not extend beyond the heavy rainfall zone. In the Deccan 

 proper only a few terrestrial species are found, and these only in the 

 vicinity of water. 



There is yet another class of orchids, of which we have no represen- 

 tative, termed Saprophytic, so called because they derive their nourish- 

 ment from decaying organic matter. In these the green coloration is 

 absent and their leaves are reduced to scales differing but little from 

 the bracts, which are the usually small leaf-like bodies subtending the 

 flowers. 



From an economical point of view, Orchids are of very trifling 

 importance. Salep is said to be produced from the tubers of some, and 

 the fragrant and aromatic substance called Vanilla is the dried fruit of a 

 species of orchid. From an horticultural standpoint, however, a great 

 number of sorts of orchids are of extreme value on account of the 

 strange forms and beauty of coloration of their flowers, and many 

 publications have been issued dealing with their culture. 



In terrestrial orchids the roots are invariably swollen atd tuberous 

 and are perennial, whilst the part appearing above ground is annual. 

 The leaves either emerge only at the surface of the ground from an 

 arrested underground stem, or they are placed singly at intervals 

 (alternate) on a more or less elongated stem. 



In epiphytic orchids the stems produced in perennial succession are 

 usually simple but sometimes branched. In the first case they are 

 often bulb-like in form or, if elongate, are more or less thickened. In 

 the second ease, where the plants are branched (a rare cecum nee) 

 the stems and branches are usually slender. In all cases the term 

 pseudo-bulb is usually applied to the stem, whether long or short. The 

 blades of the leaves are of the Monocotyledonous type, having longi- 

 tudinally parallel nerves with weak connecting veins. They differ, 

 however, from the normal type in possessing a distinct articulation 



