NOTES ON THE FLORA OP HAMILTON. 289 



greatest degree of cold correctly, I should liave little hesitation in say- 

 ing that I thought that the one or the other, or both, were unreliable. 

 As the case stands, I can only wait for further light on the subject. 



The meteorological relations above indicated are of course strictly 

 true only of the towns of Hamilton and Belleville, but they may be 

 accepted as approximately correct for the country surrounding each 

 place, and it becomes interesting to inquire whether there are differ- 

 ences in the floras of the two- places corresponding to the differences 

 in climate. Unfortunately, as the list of Hamilton plants is far from 

 complete, it is impossible to investigate this subject thoroughly, for 

 we cannot feel certain that plants reported from Belleville may not 

 hereafter be reported from Hamilton. We may venture to conclude, 

 however, that more northei'n plants will be found at Belleville than 

 at Hamilton, and that if any southern plants occur at the former that 

 do not occur at the latter place, they will be such as flower in spring, 

 and are favoured by the^ superior warmth of the Belleville May and 

 June. They will probably not be trees or shrubs, as the greater cold 

 of the Belleville winter wovild be likely to kill them. 



Imperfect as the appended list of Hamilton plants is, I find on 

 examination that it contains ninety -four species and varieties that are 

 not reported from Belleville and its vicinity. Among these there are 

 eight unimportant varieties and twenty naturalized plants. Deducting 

 the naturalized plants and also fourteen native plants that do not grow 

 in the Hamilton Valley, we have a remainder of sixty plants that 

 are probably favoured by the climatic conditions of that valley, and 

 these conditions must, from the nature of the valley, be very nearly 

 the same throughout. Of these sixty plants, by far the largest num- 

 ber flower, as might be expected, in summer and fall, when the mean 

 temperature is above that of Belleville. The months of July, August 

 and September are at Hamilton, on the average, between 1^° and 2° 

 warmer than the corresponding months at Belleville, as is shown by the 

 subjoined table. But eighteen of the sixty flower in May and June, 

 when the weather is colder at Hamilton than at BellevUle. To what 

 is the phenomenon of their occuiTence to be attiibuted'? On examina- 

 tion, eleven of the eighteen prove to be trees or ahrubs whose flower- 

 buds woiild be liable to be injured by severe winter cold, and which 

 the comparatively mild winter of Hamilton permits to flourish. For 

 the occurrence of the remaining seven, I can give no climatic reasons. 

 It would be interesting to know what influence the Great Lakes, 



