THE MOST USEFUL ORCHIDS i 25 



Uro-Skinttcri each send up an erect inflorescence, and the sweetly- 

 scented 0. c'ttrosmum differs from the rest in having pendulous 

 spikes, and also in producing these simultaneously with the appear- 

 ance of the new pseudo-bulb. 



Where do these flowers hail from ? They are found on the 

 Pacific side of the American Continent, keeping to the vast 

 mountain ranges of the Andees, and ranging from about lat. 20° 

 North to lat. 15° South, or, roughly, from Colima, at the Southern 

 end of the Sierra Madre, in Mexico, down to Cuzco, in Peru. 

 But the region in which the Odontoglossums seem most to con- 

 gregate is along the Eastern Cordillera of the Andes, from Bogota 

 Northward and North-eastward. Here, in Colombia and Vene- 

 zuela, but chiefly in the former, are the homes of such splendid 

 species as 0. crispum^ 0. nobile {Pescatorei\ 0. luteo-purpureum^ 

 and 0. tr'iumphans. 0. citrosmum comes from towards the 

 Northern limit of the genus ; 0. grande is found in Guatemala ; 

 0. Hallii from below Quito, almost under the Equator ; and 0. 

 cirrhosum, 0. Kegeljani [polyxanthum\ and 0. Edwardii each 

 extend the range farther Southward. 



The surprising part of the matter is that, although these 

 Odontoglossums are found (perhaps I should use the word " were " 

 instead of " are," because many of the species cannot be found 

 where they were originally discovered, and some have not been 

 found at all for several years past, owing to the devastation caused 

 by collectors, and in a lesser degree by the progress of civilisation, 

 in Tropical America), they can be grown successfully under quite 

 cool conditions, with very few exceptions. The reason this is so 

 is to be found in the fact that Odontoglossums grow at a con- 

 siderable elevation, the majority being found from 5000 ft. to 

 9000 ft. above sea level. This means that the temperature ranges 

 from 40° Fahr. at night up to 90' Fahr. in the middle of the day, 



