Indigenous Flora and Changes of Climate. 
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increasing severity of the seasons had been forcing the south- 
western migrations. But, if our climate is or has been grow- 
ing milder, we should expect to find the New England flora 
advancing, and northern forms receding before it. Though 
the matter is by no means so simple as this, there are certain 
facts which seem to show that the latter is nearest to the true 
state of the case. 
One ground for this opinion is found in the widely separated 
stations and scattered growth of plants of a northern range. 
Of a list of about one hundred and forty species that are more 
abundant elsewhere than within our province, nearly one 
hundred are of distinctly northern or northwestern distribu- 
tion. Such a large majority seems to prove that the causes, 
whatever they are, which hinder such scattered plants from 
growing abundantly here are acting most strongly upon those 
of a northern range. 
What at first appears as an objection to the argument is 
the fact that there are twelve southern species in this list of 
scarce plants. They are as follows: 
Lecliea minor, 
Sporgularia rubra, 
Ilex verticillata, 
Gaylussacia dumosa, 
Fraximis pul)esceus, 
Li mnan t h em u m 1 acu n os u m , 
Polygonum bydropipcroides, 
P. arifolium, 
Xyris flexuosa, var. pusilla, 
Cy perns esculentus (= phymatodes), 
Scirpus atrovirens, 
8. Clintonii. 
Add to these Eleocharis Robbinsii, found in one locality in 
New Brunswick, and not yet reported in Maine, and we 
liave a list of thirteen scattered southern forms. But it will be 
found that all but one of them are plants growing in water or 
in wet places, and just such as could be most easily carried 
by arpiatic birds; and it may be argued that their seeds were 
brought here as plentifully at earlier times when birds of 
passage would have been as abundant as at present, and that 
a higher summer temperature is only now beginning to admit 
of their growth. 
The continued existence of an isolated group of northwestern 
plants in the St. John valley is evidence that our climate has 
not since glacial times been very much warmer than at present; 
