Phenological Observations in Canada. 75 



Again, the tyro botanist is at a disadvantage, for he 

 does not know where to look for the rarer species, and 

 when he accidentally comes across them they may have 

 been in Hower for some time. It is very likely that the 

 average dates of the flowering of plants in IsTova Scotia in 

 the various counties may be slightly affected by this 

 source of error, the counties having the oldest and most 

 enthusiastic botanists appearing to be earlier in season. 

 This may account for the unexpectedly advanced position 

 of Pictou county in the table following. 



Then there is the accident of local land inclination or 

 shelter, for the warm intervals on the southern slope of 

 the hill is earlier than the northern slope. To estimate 

 these local effects, the schedules from each county in 

 ISTova Scotia from this year forward are to be classified 

 into localities : (1) on the coast, (2) low inlands, and (3) 

 highlands. 



And lastly, some individual plants are naturally earlier 

 than others even when in similar localities, and in the 

 same individual certain twigs and branches are earlier 

 than others. To check such peculiarities an attempt is 

 made to fix the date when the flowering of each species 

 may be said to be " becoming common." So that we have 

 the two series of observations for each individual, the 

 " first appearance " and the " becoming common." 



So much for the history of the work and the general 

 lines upon which it is being conducted. 



Assuming the observers to be symmetrically placed in 

 a country, to be competent and careful, and to put exactly 

 the same interpretation on what constitutes the " first 

 appearance " and " when becoming common," the averaging 

 of the various observations would give us phenological 

 norms for the comparison of a very important character 

 of the country with that of another, and more especially 

 for the comparison of one season with another in the same 

 country, which after a series of years would contribute to 



