140 ROYAL SOCIETY OF CANADA 



insect, and as one walks over the bogs there is no rising of insects about 

 his feet, as is the case in lields at the same season. The bogs always seem 

 larger than they are, and objects seen on them seem smaller than they 

 ou"-ht for the distance. They at all times conve}' an impression of lone- 

 liness, not \inpleasant, and recalling the feelings inspired by the desert. 



3. The Ecological Characteristics of the Vegetation of the 



Raised Bogs. 



The features which the flowering plants of the bogs have in common 

 are as follows : 



1. Northern range. 



2. Xerophilous sti'ucture. 



3. Depauperation in size. 



4. Late unfolding of leaves and flowers. 



5. Great extent of under-moss parts. 



The northern range of the species growing in great peat bogs is very 

 well known and understood, and its causes have already been briefly 

 referred to. In New Brunswick, the presence of these northern forms 

 has been investigated by Matthew (14a) and Fowler (G), though not 

 especially as to their occurrence in the bogs. 



The xerophilous, or water-saving, chai-acter shows itself in three 

 ways : 1st. In the groups which comprise them ; nearly all of the flowering 

 plants of the bogs belong to the three families, Ericacea\ Coniferte and 

 Cyperacew, all of them families of marked xerophilous tendencies. 2nd. 

 In the depauperation, though not as the chief cause of this. 3rd. In the 

 tendency to condensed form, leathery texture, infolded leaves, Avhich the 

 plants on the high bog show in comparison with the same species otf the 

 bog. The ecological significance of xerophily in bog plants has been 

 most satisfactorily shown by Goebel (11) and Kihlman (12) ; it lies 

 primarily in the fact that when the temperature of the soil is reduced 

 below a certain point, which may be considerably above freezing, the 

 roots are unable to take up moisture, and unless provision is made to pre- 

 vent too great evaporation, the plant may die of thirst though immersed 

 in water. This low temperature must often bo reached in these cold 



bogs. 



The very marked depauperation ot the flowering i)lants alfects all 

 parts of their structure. Trees 20 or 30 years old are under a toot in 

 heio-ht and less than a half inch in diameter, and shrubs are but 6 inches 

 high and bear but few leaves, branches, flower-clusters and flowers ; and 

 all are much smaller than the normal ones ort' the bog. One cause of 

 depauperation has been mentioned — xerophily ; but this alone is not 

 suflicient to explain the facts, for on flatter bogs the same species are 

 always larger. It cannot be coldness of the water retarding growth, as 



