/ong, leading doubtless to the sphagnum bog. Their destruc- 

 tion will be largely due to detritus washed from above. 



A small pond in the Northwest basin, situated at the base of 

 heavily wooded slopes, and receiving some residuum, is now 

 Hearing its temporary climax. Its life history will be com- 

 paratively short, leading to a small natural meadow. The 

 shores are now bordered with a fast encroaching meadow, and 

 similar islands almost spanning the pond make its future very 

 evident. Upon the islands spruces have already appeared. In 

 this meadow society grow Scirpus ccespitosus, Carex rigida 

 Bigelovii, Aster radula. Aster umb elicit us, Lyco podium inun- 

 datum, and many other less prominent forms. 



(b) The Sphagnum Bog Society. In the great basin, near 

 the outlet of Lower Basin pond, is located a small sphagnum 

 bog. In a deep morainic depression, and isolated from the receipt 

 of much detritus, its life history has doubtless been of great 

 length. With the exception of a few open spots (Fig. 9) the 

 once rocky shored pond is completely captured by sphagnum 

 and its associated forms. By a study of these open places we 

 are able in a measure to interpret the past order of succession, 

 for we have here in miniature what presumably took place in 

 the bog as a whole. The Sphagnum advances from the edge, 

 dying down below. As it grows above it continually opens the 

 way for further encroachment. The opening is finally spanned 

 and a soil is formed. Upon this Scheuchzeria palustris appears, 

 even before the substratum reaches the surface. As the 

 soil reaches the surface Drosera rotundifolia and D. longifolia 

 come in. As the Sphagnum continues its growth and the con- 

 dition becomes drier Sarracenia pur pur ea appears. 'Associated 

 with it are Vaccinium oxycoccus and Smilacina trifolia. With 

 still drier conditions Eriophorum gracile, Carex trisperma, and 

 the characteristic Carex paucinorum become constituents of the 

 bog flora. The heaths next appear.- Cassandra calyculata, 

 Kalmia angustifolia, Kalmia glauca, and Ledum lati folium are 

 abundant, occurring in the order named. With these, Pyrus 

 arbuti folia and Viburnum cassinoides are common. Other 

 forms whose place in this succession was undeterminable but 

 which are very significant are Hmpetrum nigrum, Vaccinium 

 uliginosum, and V. Vitis-Idaea. 



43 



