Il8 UNIVERSITY OF MISSOURI STUDIES [260 



99. SISYRINOHroM L. Blue-eyed grass. 



270. S. campestre Bicknell. 

 Thickets and open wild places. 



Wisconsin to North Dakota; Louisiana to New Mexico. 



271. S, graminoides Bicknell [5. anceps Watson], 

 Low grassy places; frequent. 

 Newfoundland to Minnesota; Florida to Texas. 



Order II. MICROSPERMALES. 

 Family 21. ORCHIDACEAE Lindl. Orchis family. 



100. OYPRIPEDIUM (OYPRIPEDILUM) L. 



Lady's slipper. 



272. C. pubescens Willd. [C. /z^WaA/wiMill.]. Large yel- 

 low lady's slipper. 



Rich bank of Grindstone creek; only one plant dis- 

 covered. 



Nova Scotia to Minnesota and South Dakota; Georgia 

 to Missouri and Nebraska. 



273. O. parviflorum Salisb. Small yellow lady's slip- 

 per. 



One plant in a deep ravine south of Hinkson creek; a 

 plant was also collected by Charles Thorn, five miles south 

 of Columbia. 



Newfoundland to British Columbia; Georgia to Mis- 

 souri and Washington. 



lOL SPIRANTHES L.C.Rich. \_GYROSTA- 

 CHYS Pers.]. Ladies' tresses. 



274. S. cernua (L.) L. C. Rich. \G. cerniia (L.) Kuntze]. 

 Thickets and wild pastures; scarce. 



Nova Scotia to Minnesota; Florida to Texas. 



275. S. gracilis Bigel. [G.^r<z<r2yw(Bigel.) Kuntze]. Slen- 

 der ladies' tresses. 



Dry thickets and hill summits; very rare; one plant gath- 



