LlMNORCHIS AND PlPERIA NORTH OF MEXICO 609 



[limnorchis dilatatiformis Rydb.*). This differs from L. dilatata 

 mainly in the shorter, more clavate spur, the dull or greenish white 

 flowers and the usually smaller size. It approaches much the 

 form referred to above under L. Jiypcrborca viz. Habcnaria borealis 

 $viridifiora Cham., and in fact connects the L. Jiyperborea and the 

 L. dilatata groups. The other specimens from the West labeled 

 Habcnaria dilatata belong to L. leucostachys and a few of the new 

 species described below. No specimen of L. dilatata has been 

 seen from any place west of Minnesota. 



Lindley in his Genera and Species of Orchideous Plants de- 

 scribed the following species which fall within the limits of Lim- 

 norchis : Platanthcra convallariaefolia, P. leucostachys, P. gracilis, P. 

 stricta and P. gr amine a. While staying at Kew in July this year, 

 I had the privilege of seeing Lindley's herbarium as well as Doug- 

 las' plant preserved at Kew, which has enabled me to verify my 

 determinations. 



P. convallariaefolia was described from specimens collected in 

 Kamtchatka by Fischer. It is a species resembling a slender L. 

 dilatata, but the lip is linear, not at all dilated at the base, the 

 spur is filiform and about the length of the lip and the lower leaves 

 are oblanceolate and obtuse. In the Torrey herbarium there is a 

 specimen communicated by Lindley. This is evidently a cotype 

 of that in Lindley's own collection for the two are as like as they 

 can be. In Torrey's herbarium there is also another specimen, 

 collected on Unalaska, which I also refer here. 



P. leucostachys was described from a specimen collected by 

 Douglas. This is in the herbarium of the Kew Gardens. In 

 this specimen the spur is slender, filiform, not at all thickened and 

 not very obtuse at the apex. There is a form also common 

 the Columbia valley with the same habit but with the larger spur 

 much more clavate and very obtuse at the apex. If this should 

 be regarded as a form of L. leucostachys or as a distinct species is 

 a question of which opinions may differ, but it is, however, im- 

 portant to know what the original P. leucostachys was. 



P- gracilis is a slender plant with the white flowers of L. dila- 

 ta to, but the lip is linear and the spur decidedly clavate. In 

 reality it is nearest related to P. convallariaefolia, from which it dif- 



m 



Mem. N. V. Bot. *Gar. i : 105. 1900 



