118 The Ottawa Naturalist. [Oct. -Nov. 



lobatis juventate subtus in coslis et nerviis et marginibus 

 petioli floccoso-tomentulosis deniquc glabratis, lobis oblongis 

 ad apicem rotundatis integris vel obtusodentatis; inflorescentiis 

 dense corymboso-cymosis ; capitulis 8-10 mm. altis radiatis; 

 involucris campanulatis calyculatis parce floccoso-tomentulosis 

 glabratis. squamis involucri ca. 21 lineari-lanceolatis 6-7 mm. 

 longis acutis; floribus femineis ligulatis ca. 12, ligulis flavis; 

 floribus disci 60-70; achaeniis glabris. Alberta: near Olds, 

 August, 1894, W. W. Willing (hb. Geol. Surv. Canada, nos. 

 14843, 6063; fragment and photograph in hb. Field Museum). 

 Here also is referred doubtfully a specimen collected in gravelly 

 soil at Ninga, Manitoba, 1 June, 1908, B. J. Hales, no. 24 (hb. 

 Geol. Surv. Canada). 



This species stands nearest to 5. plattensis Nutt., but differs 

 in its subglaucus character, smooth and stronglv striated stem 

 and glabrous achenes. 



Senecio canus Hook., var. acraeus, var. now 



Caulis 3-4 dm. altus; foliis oblanceolatis vel lanceolatis 

 subintegris vel irregulariter inciso-dentatis 4-10 cm. longis 

 0.5-1.5 cm. latis juventate utrinque lanato-tomentosis supra 

 denique glabratis; inflorescentiis corymbo-cymosis, pedunculis 

 per longis. Saskatchewan : Spy Hill, 23 June, 1879, /. Macoun, 

 no. 52 (hb. Grav), tvpe: on dry gravellv slopes, Spv Hill, 

 "N.W.T.," 26 June, 1879, /. Macoun (hb. Geol. Surv." Canada, 

 no. 14837 in part). 



The variety here described is a somewhat taller plant than 

 the species proper with more deeply cut stem-leaves and with 

 a tendency for the upper leaf-surface to become more or less 

 glabrous; furthermore the inflorescence is more open and has 

 relatively long branches. 



NOTES ON NATIVE ORCHIDS. 



By Charles Macnamara, Arnprior, Ont. 



Among other peculiarities of our native orchids may be 

 mentioned the surprising manner in which a species will sud- 

 denly appear in some place where it w r as rare or unknown before, 

 only to disappear again in the next year or two. No doubt all 

 plants have their "off" years, but why perennials like the orchids 

 should disappear as suddenly and completely as they do, it 

 is hard to say. Their unexpected appearance is probably 

 due to the exceedingly light nature of their seeds, which a fortu- 

 itous wind may carry long distances. But whatever the cause, 

 this remarkable habit adds great zest to orchid hunting, for 



