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the Canadian Life Zone. The chief components of the Canadian 

 forest found here are: Tsuga canadensis, Pinus resinosa, Picea 

 rubra, Abies balsamea, Betula lutea, Amelanchier oligocarpa, 

 Pyrus americana, Primus pennsylvanica, Acer spicatum, A. 

 pennsylvanicum, Viburnum alnifolium, and Sambucus racemosa; 

 while on the forest floor may be found Clintonia borealis, Strep- 

 topus roseus, Maianthemum canadense, Trillium undulatum, 

 Chrysosplenium americanum, Oxalis acetosella, Cornus canaden- 

 sis, Chiogenes hispidula, Linnaea borealis americana, and many 

 others. Even the following Hudsonian species occur on exposed, 

 wind-swept summits: Betula papyrifera, Ribes prostratum, Ru- 

 bus strigosus, Potentilla tridentata, Aralia hispida, etc. 



Here and there throughout the higher mountains, where the 

 drainage is impeded due to resistant masses of conglomerate or 

 other sandstone, are formed topographic features known locally 

 as "glades," which resemble in a striking manner the bogs of 

 farther north. In these glades may be found species of Sphag- 

 num, Cladonia, etc., as well as such vascular plants as Aspidium 

 simulatum, Larix laricina, Car ex trisperma, Pogonia ophioglos- 

 soides, Calopogon piilchellum, Alnus incana, Coptis trifolia, 

 Drosera rotundifolia, Geum rivale, Vaccinium oxycoccos, V. mac- 

 rocarpon, and Menyanthes trifoliata. 



A number of species have apparently first appeared in the 

 southern Appalachians as a result of evolution from some other 

 types, and persist in the higher elevations, not as portions of the 

 Canadian flora surrounding them, but as peculiar Appalachian 

 forms. Among such are Car ex Fraseri, Melanthium parviflorum, 

 Stenanthium gramineum , Listera Smallii, Thalictrum clavatum, 

 Cimicifuga americana, Aconitum vaccarum, A . uncinatum, Traut- 

 vetteria carolinensis, Magnolia Fraseri, Dicentra eximia, Parnas- 

 sia grandifolia, P. asarifolia, Boykinia aconitifolia,Saxifraga mic- 

 ranthidifolia, Pachistima Canbyi, Euphorbia Darlingtonii, Men- 

 ziesia pilosa, Rhododendron catawbiense, Vaccinium erythrocar- 

 pon, and Phlox stolonifera. 



In addition to the above-mentioned deciduous and ever- 

 green forest types, there occurs a third type of plant association, 

 covering many square miles in a narrow strip along the eastern 

 border, to which Steele (7) has given the name Shale-Bar- 

 rens. This is characterized (10) by a sparse, scrubby growth of 

 Pinus virginiana, P. pungens, Quercus ilicifolia, Kalmia lati- 



