be entertained of its inhabiting a damp, .cool, shady situa- 

 tion. This certainly reveals the secret of its cultivation, and 

 shews that a very diflPerent climate from that of East and 

 West Indian Orchidaceae is requisite for it. Probably it 

 will like the management recommended for Lsslias at pages 

 26 and 27 of this work for 1839, and most undoubtedly it 

 must be guarded against exposure to a high temperature at 

 any period of the year. 



With reference to this subject cultivators will probably 

 be glad to see the following extracts from Humboldt's ac- 

 count of the Mexican climate. 



" Mexico in lat. 19' 25', at the height of 7OO8 feet, has a 

 mean temperature of 63° ; that of the hottest months is from 

 60*^ to 70° ; of the coldest months 50" to 59". 



" Toluca in lat. 19" 16', at the height of 8280 feet, has a 

 mean temperature of 59". 



" On the Puerta del Volcan, a volcanic mountain, near 

 Toluca, at the height of 10,494 feet, the temperature of a 

 rivulet flowing down from it is about 49"." 



Humboldt does not mention Orchidaceae in his list of 

 plants growing within the boundary of this tierra fria ; but 

 he speaks of Peperomia umbilicata, Cheirostemon platanoides, 

 Rosa Montezumse which is our R. canina, Hoitzia coccinea, 

 a Strawberry, and common Horehound, among many other 

 plants. 



