iv PREFACE. 



I am not sufficiently acquainted with the details of Mr. 

 Linden's journey in Colombia and Cuba to offer any physiological 

 observations upon this collection, except in relation to the 

 climate in which his species grew. This, however, is of con- 

 siderable interest, and deserves to be very carefully considered 

 by all cultivators. 



It was not without reason that Humboldt thus characterised 

 the Orchids of Equatorial America. "Although,'' says that 

 illustrious philosopher, "such plants are scattered through 

 every part of the torrid zone, from the level of the sea to the 

 height of ten or eleven thousand feet, yet it must be admitted 

 that in the number of species, the colouring of their flowers, 

 delicious fragrance, rich foliage and brilliant colours, none can 

 be compared with those which inhabit the Andes of Mexico, New 

 Granada, Quito and Peru, where the shade is moist, and the 

 breezes mild, the mean temperature of the year at an elevation 

 of between 4800 and 6600 feet, being from 64° to 69°." Mr. 

 Linden's collection shows that of 129 species nearly half are 

 found in such localities. 



If, however, any general conclusions are to be drawn from Mr. 

 Linden's useful notes, it is necessary to examine the species in 

 detail, and for that purpose they are classified in the following lists 

 according to their elevation above the sea; the temperature of each 

 group being computed from the data furnished by Humboldt: — 



12,000 to 13,000 feet. {Mean Temp. 40°). 

 Epidendrum frigidum. 



11,000 t0 12,000 feet. (Mean Temp. 46°). 



Restrepia parvifolia. 

 maculata. 



Masdevallia polyantha. 

 Epidendrum chioneum. 



Masdevallia affinis. 



10,000 to 11,000 feet. {Mean Temp. 49° ; Min. Temp. 32°). 

 Pleurothallis aurea. 



Lindenii. 

 ~ intricata. 



Dialissa pulchella. 

 Masdevallia tubulosa. 



caudata. 



aflfinis. 



Epidendrum tolimense. 



_ fimbriatum, 



■ refractum. 



Odontoglossum densiflorum, 

 Paehyphyllum crystallinum. 

 Telipogon angustifolius. 



