382 George E. NicJwls, 



rubrotinctits, Carex canescens disjuncta, C. crinita, C. paupercula 

 irrigua, Juncus filiformis, Slum cicutacfolmm and Galium 

 palustre. Considerable patches have been preempted by Myrica 

 Gale, while Sphagnum imbricatum is locally abundant. From a 

 superficial study it would appear that at the present time the 

 fresh swamp, presumably as a result of the comparatively recent 

 complete cutting off of MacDonald Pond from the sea and the 

 consequently decreased salinity of the water, is gradually 

 encroaching on a former brackish marsh whose vegetation over 

 most of the swamp is now represented only by scattered relicts. 

 But, as a matter of fact, the situation is much more complicated. 

 This is merely suggested here, without attempt at explanation, 

 by the facts (i) that while there are no living trees in the 

 swamp there are numerous dead spruces, and {2) that a sample 

 of the peat taken near the margin of the central pond showed 

 abundant sphagnum remains at a depth of twelve feet below the 

 surface. 



Another interesting transitional series, in this case from salt 

 pond to boggy swamp, was observed along the shores of North 

 Pond, Aspy Bay. Here, starting from low water mark and 

 proceeding inland, within a distance horizontally of scarcely a 

 hundred feet one passes through the following associations : (a) 

 Sparitina glabra alterniflora and Spergularia canadensis; (b) 

 Spartina patens; (c) Juncus balticus littoralis, Agrostis alba 

 maritima, and Ranunculus Cymbalaria; (d) Scirpus occidentalis; 

 (e) various species of Carex, Alnits incana, Myrica Gale, 

 Vacciniitm macrocarpon, Chrysophynum stellatum, etc. ; (/) 

 boggy swamp with Carex trisperma, Rynchospora alba, Sarra- 

 ccnia, Drosera rotimdifolia, Vaccinium Oxycoccus, Chamae- 

 daphne. Ledum, various Sphagna, etc. Area a-c are below 

 mean high tide level, area d is partly above and partly below, 

 area e is barely out of reach of ordinary high tides, and area 

 / extends down to within less than a foot (vertically) of mean 

 high water mark. 



In discussing the occurrence along the shore of Cold Spring 

 Harbor of non-halophytic vascular plants, in places where the 

 soil is often covered by salt water, sometimes for as much as 

 tliree or four hours daily, Johnson ('15, p. no, etc) explains 

 the situation somewhat as follows. The ground in such places is 

 usually springy, and the soil is saturated with fresh water, the 



