2 ORCHIDACEJE 



lobe appears emarginate ; near the sinus of the lobes a callus, 

 and at the concave base of the lip a thickening of the tissues. 

 Column minute, with a rostellar projection in front below the 

 clinandrium. Pollinia 4, pyriform. 



A. sphacelatum is closely related to A, tenellum, Nees & 

 Meyen, but is distinguished from it by the accumulation of slight 

 differences to be observed throughout the inflorescence. The 

 form of the floral bracts, larger size of the flowers, very different 

 lip, and the more slender column are all distinctive characters 

 which show clearly the identity of the new plant. The lip of A. 

 sphacelatum is difficult to study on account of the rigidly de- 

 flexed apex of the mid-lobe, and when forcibly straightened out 

 becomes torn. The lip of A. tenellum, on the other hand, spreads 

 out easily and the mid-lobe is less decurved at the apex. Habi- 

 tally there is very little dissimilarity between A. tenellum and 

 A. sphacelatum, and the two species might readily be confused. 

 In my dissections I have been unable to find the arms or wings 

 of the column which are so characteristic of the related genus 

 Platyclinis. 



The type was collected by A. D. E. Elmer on June 1, 1904, on 

 Mt. Santo Tomas, Province of Benguet, Luzon, Philippine Islands 

 (No. 6554). According to field notes the plants form large tufts 

 chiefly on living trees and produce pendulous or recurved racemes 

 of light brown or yellow flowers. 



