1904] Relatiomship between Weather and Plant Growth. 47 



noticed Unifoliiun Canadense in bud as early as the 2gth of April. 

 On the 1.5th May I have the following note: "Most of the bunches 

 of buds of Unifolhim Canadense have shrivelled up; others — lately 

 developed probably — are about ready to open, but rain is needed !" 

 The flowers expanded about a week later. This was in Beech- 

 wood Cemetery. At Chelsea they came into bloom about a week 

 earlier than here and at the same time as the previous year but 

 not so abundantly. Wild columbine, which already had larg^e 

 buds on the 27th April, seemed to be affected by the drouth, 

 being very slow in opening its buds in May. In the middle of 

 May, 1902, I found plenty of Capnoides semper^irens in bloom on 

 the rocks of the island at Chelsea ; at the same time last year I 

 could find no trace of the plant, I found Anemone riparia in 

 bloom in abundance at the Beaver Meadow very early in June, 

 1902 ; last year I did not find it there at all. Several plants 

 found blooming in the lane near the bridge at Beaver Meadow, 

 Hull, in 1902, were not to be seen there in 1903, as Sedum acre 

 and Capnoides aureuni. Iris versicolor \\3.s abundantly in bloom in 

 the swampy ground near by very early in June, 1902, but not last 

 year, I found Tripoliiim aiireum earlier in bloom last June than 

 the previous June, but its growth was stunted. Twin-flower and 

 the pitcher plant were burnt brown by the heat where exposed.* 

 The drouth had probably something to do with all these failures. 



At the end of April, 1902, I found Draba nemorosa pretty 

 abundantly in bloom along the river bank at T^treauville, and be- 

 fore many days its little yellow flowers covered the ground. Last 

 year 1 was unable to find the plant at all. The dry spring was 

 probably unfavorable to its growth. Prof. Macoun, to whom I 

 am indebted for much cheerfully given help in this investigation, 

 told me that Draba nemorosa had been found only once before 

 around Ottawa, namely in 1900 by himself near the St. Louis 

 Dam. Other rare plants I found in bloom in 1902 are Cyno- 

 glossu7n virginicum, 17th June, at T^treauville ; Syniphoricarpos 

 racetnosiis, 28th June, at Rockliffe; Heracleuni lanatum, 28th June, 

 near the mouth of the creek draining Hemlock Lake; and in 1903, 

 25th May, Corallorhiza corallorhiza at Britannia. 



It was not the purpose ctf this paper to compare these two 

 seasons in detail with the preceding. I have also not dealt with 



