78 ORCHIDAOEM 



The following brief generic characterization becomes necessary 

 in view of recent additions to the number of species : — 



Sepals and petals free, spreading, equal, or the petals sometimes 

 broader than the sepals. Labellum sometimes slightly saccate at 

 the base, often with elevated lines or keels on the disc, entire, or 

 2- or 3-lobed, the lateral lobes spreading or erect, often with 

 rounded calli at their bases. Column elongated or very short, 

 simple, or with wings or teeth produced from the base, middle, 

 or tip, and with a terminal entire or variously toothed or crenate 

 wins- behind the anther ; anther small, 2-celled. Pollinia 4, waxy. 

 Rostellum prominent. — Epiphytes with tufted semi-fusiform or 

 rounded monophyllous pseudobulbs, clothed with scarious sheaths. 

 Leaves various, terete-filiform to broadly lanceolate, convolutive 

 or duplicative in the bud. Flowers white, green, yellow, or brown- 

 ish red, distichous. Racemes often drooping, remarkable for the 

 glumaceous scarious bracts with involute margins which conceal 

 the pedicel and ovary. 



KEY TO THE PHILIPPINE SPECIES OF DENDROCHILUM 



I. Inflorescence laterally produced, on a leafless sboot. § Eudendrochilum. 



II. Inflorescence terminal on a leaf-bearing shoot. Column simple, neither winged nor 

 toothed. § Acoridiuni. 



III. Inflorescence terminal on a leaf -bearing shoot. Column winged or toothed. 



§ Platyclinis. 

 I. Eudendrochilum. 1- D. Woodianum. 



II. Acoridium. 



A . Lateral lobes of the labellum larger than the middle lobe or subequal to it. 

 1. Leaf grass- or sedge-like, linear, acute. 



a. Peduncle affixed to the face of the leaf or lightly adhering to it, 



appearing to arise from near its tip. 

 *Leaf terete. 



fMiddle lobe of the labellum not rigidly deflexed. 



2. D. tenellum. 

 ffMiddle lobe of the labellum rigidly deflexed. 



3. D. sphacelatum. 



**Leaf triangular-setaceous. 4. D. Williamsii. 



***Leaf flat. 5. D. graminifolium. 



b. Peduncle free from the leaf, at least not adhering to its face. 



*Lateral lobes of the labellum falcate. 6. D. exile. 



**Lateral lobes of the labellum linear-oblong. 



7. D. tenuifolium. 



