428 Proceedings Portland Society Natural History 



marsh only by the extreme halophytic conditions which pre- 

 vail there. 



V. COMPARISONS WITH OTHER REGIONS 



The vegetation of the Penobscot Bay region of the Maine 

 coast shows a marked resemblance to that of other locali- 

 ties within the Canadian transition zone of the Transition 

 Forest region, for which data are available. Unfortunately 

 comparatively little ecological work has been done in this 

 area and almost none so far as the succession of vegetation 

 is concerned. Some idea of the nature of the climax forest 

 can be gained from the publications of foresters, but these 

 are primarily economic in character and do not consider at 

 all the dynamics of the vegetation. The most valuable 

 works in this connection are those of Chittenden (3), Fer- 

 now (7, 8), Frothingham (9), Hawley and Hawes (11), 

 Macoun (17) and Murphy (20). Papers of an ecological 

 nature which deal with the area, in addition to those previ- 

 ously referred to, include those by Ganong (10), Howe 

 (16), Moore (18, 19), and Transeau (29). The most 

 striking feature brought out by these papers is the similari- 

 ty in the climax forests of the several regions described. 

 Whether it be the Maritime Provinces, northern New Eng- 

 land, the Adirondack Mountains of New York, or the Pe- 

 nobscot Bay region of Maine, the climax association-type 

 is a mixed coniferous deciduous forest with sugar maple, 

 beech, hemlock, yellow birch, spruce and balsam fir the pre- 

 dominant trees. This is the culminating type of vegetation 

 on areas of optimum drainage, deep loose soils and moderate 

 slopes. 



Not only does the Penobscot Bay region agree in its cli- 

 max forest — the regional climax association-type — with the 

 rest of the larger area of which it is a part but also in re- 

 spect to the various physiographic climaces which occur. 

 The development of the spruce-fir forest on the thin soils 

 of the islands and the outer portions of the mainland is sim- 



