viii INTRODUCTION 



the species just named, inasmuch as it should include them, or be redefined 

 or abandoned. Based, as it now is, on rudimentary column arms or their 

 absence, it merges with the subgenus Acoridium, which is characterized 

 by the total absence of the column arms, a condition quite overlooked 

 in the Conspectus. If it is redefined so as to include only those species 

 with rudimentary column arms such as D. Kingii, then D. Merrillii, which 

 is most readily distinguished from D. Kingii by the absence of column 

 arms, is widely out of place in its present position at the end of the sub- 

 genus Acoridium, where Dr. Kranzlin has placed it. In my disposition 

 of D. Merrillii I preferred to keep it among the true Acoridiums, yet 

 recognizing its affinity with the species of the subgenus Platyclinis by 

 bringing it in juxtaposition with them. Dr. Kranzlin has not seen fit to 

 depart far from the order of the species which I adopted under Acori- 

 dium proper in my paper published in the Proceedings of the Biological 

 Society of Washington, although in preparing a key to them he has 

 altered the position of several. 1 By this blind adherence to my arrange- 

 ment without due regard to the raison d'etre of the order of the species 

 in the remainder of his paper he has missed the spirit of my classification 

 without improving that of his own ; consequently he has removed D. Mer- 

 rillii as far as possible from D. Kingii. Furthermore it is well to note 

 that Dr. Kranzlin does not pretend to conform to the requirements of the 

 Conspectus, as his new species D. tenuissimum, characterized as being 

 without column arms, is placed in the subgeuus Platyclinis. 2 



To those who may look to the Pfitzer-Kranzlin monograph of the 

 Ccelogyninse for a complete review of the species of Dendrochilum pub- 

 lished up to the early part of 1907, disappointment must result. The 

 oversight of Dr. Schlechter's new species may be attributable to inor- 

 dinate haste in the preparation of the work, although that explanation 

 of their absence from it will scarcely be satisfactory when it is realized 

 that these appeared in such a prominent serial as the Bulletin Herbier 

 Boissier, ser. 2, vol. 6 (1906). 



1 In this Key under C the contrasting characterizations "Pedunculi infra inflorescentias 

 nudi " and " Pedunculi infra inflorescentiam bracteis paleaceis imbricantibus vestiti " are abso- 

 lutely unwarranted by the material on which they are based, and must ever prove perplexing 

 and misleading. It is to these inadequate distinguishing characterizations that Dr. Kranzlin' s 

 departure from the order of species adopted in the paper referred to is due, and not to an 

 attempt to harmonize my material with the views expressed by the Conspectus. 



2 D. cinnabar inurn Pfitzer, a new Philippine species from Benguet, Luzon, which is also 

 found among the species of the subgenus Platyclinis properly belongs in subgenus Acoridium, 

 where it should be placed near D. affine. It is destitute of stelidia, and furthermore is inac- 

 curately described by Dr. Pfitzer as to its labellum, which is 3-lobed, with the middle lobe 

 hastate, acute, bicallose at base, 2 mm. long, and with the lateral lobes 1 mm. long, oblong- 

 obtuse. The figure in Das Pflanzenreich does not show the lateral lobes. 



