ORCHIDACEiE 



genus Aphanostelidion and well characterized by the simple 

 gjTiostemium which lacks stelidia. D. simplex has not hereto- 

 fore been recorded from Mount Kinabalu. 



Among the new species described below there are several that 

 are of unusual interest, as they seem to indicate the probable 

 existence of alliances that may reward intensive explorations of 

 the higher altitudes of Borneo. 



Dendrochilum quinquelohum Ames,Z). exasperatum Ames, and 

 D. Haslamii Ames, together with the closely related D. Gibbsiae 

 Rolfe and D. fdnabaluense Rolfe, constitute through the struc- 

 ture of the Up a very distinct group that may be largely in- 

 creased in numbers as botanical explorations proceed. D. quin- 

 quelohum differs from its allies in the strongly reflexed, falcate 

 terminal lobes of the hp beyond which the fifth lobe or large 

 cusp protrudes. The Up of D. Gibbsiae and of D. Jdnabaluense 

 resembles more closely the Up of D. Haslamii than that of 

 D. quinquelobum. 



Dendrochilum alatum Ames, D.fimbnatum Ames, and Z). Jo- 

 clemensii Ames are clearly distinguished from all other species 

 by means of the elUptical or very broad, round-tipped stelidia 

 or wings of the column. From the description Z). latibrachiatum 

 J. J. Sm. would seem to be a member of this group. 



One would expect to find elements of the Philippine orchid 

 flora represented in Dendrochilum on Mount Kinabalu. This ex- 

 pectation, however, is not fulfilled. Take for example the paucity 

 of species on the mountain referable to the groups that lack ste- 

 lidia on the column, and then consider the wealth of species refer- 

 able to § Acoridium that have been found in Luzon. § Acoridium 

 is devoid of stelidia. There is not a single Acoridium in the Pfit- 

 zerian sense recorded as having been found on Mount Kinabalu, 

 and yet forty-four species of this section of the genus are natives 



[44] 



