12 ORCHIDACEM 



The column of typical Platyclinis has been relied on to a large 

 extent in the determination of species. The column is variously 

 winged, with the wings usually strongly developed, arising basally, 

 or from the middle, or from the summit. In such forms as Den- 

 drochilum palawanense and D. rufum J. J. Smith, however, the 

 wings are reduced to mere teeth; therefore the column in these 

 species begins to approach the form characteristic of Acoridium 

 as represented by D. Merrillii. The column of typical Dendro- 

 chilum species has arms or wings as in Platyclinis ; and no ge- 

 neric differences of any kind can be discerned in the flower. The 

 only considerable difference is in the origin of the inflorescence, 

 as before stated ; but I agree with J. J. Smith in denying generic 

 worth to this feature. The passage from one condition to the 

 other is so easy, that the position of the flower shoot must not be 

 relied on too much. Dendrochilum receives Platyclinis and conse- 

 quently Acoridium. 



I have lately published several new species in this genus (Proc. 

 Biol. Soc. Wash. 19: 143, 1906). The names first given must 

 now be changed. Acoridium Williamsii, A. graminifolium, A. 

 tenuifoliwn, A. tenue, A. parvulum, A. venustulum, A. stricti- 

 forme, A. anfr actum, A. recurvum, A.philippinense, A. turpe, 

 A. oliganthum, A. ocellatum, A. Merrillii, A. longilabre, A. 

 graciliscapum, A. cucullatum, and A. Copelandii become Den- 

 drochilum WlLLIAMSII, D. GRAMINIFOLIUM, D. TENULFOLIUM, 

 D. TENUE, D. PARVULUM, D. VENUSTULUM, D. STRICTIFORME, D. 

 ANFRACTUM, D. RECURVUM, D. PHILIPPINENSE, D. TURPE, D. 

 OLIGANTHUM, D. OCELLATUM, D. MERRILLII, D. LONGILABRE, 



D. graciliscapum, D. cucullatum, and D. Copelandii. These 

 species are portrayed in the plates which follow. 



