392 Annals of the Carnegie Museum. 



The Driftwood Habitat. 



The region included in this habitat is the eastern shore of Misery- 

 Bay, extending from the U. S. North Pier to the mouth of Niagara 

 Pond. The shore is here fronted by an old line of wooden piers which 

 serve to some extent to protect the shore from the force of the 

 waves. The sandy bottom slopes gradually from the shore, at least in- 

 side the line of piers, and the westerly winds have piled here much 

 driftwood and floating rubbish of all sorts. 



The sand-plain extends almost to the water's edge along the southern 

 two-thirds of this shore, but along the northern third the Prunus forest 

 formation has occupied the corresponding area. With the decay of 

 the driftwood much organic matter is mixed with the sand, which is 

 continually being blown over from the sand-plain, and the result is a 

 dark -colored sandy loam with a very high huniic content. The struc- 

 ture of the vegetation along this shore is essentially as follows : 



{a) Potamogeton Formation. 

 (/^) Typha-Scirpus Formation. 

 (^) Sagittaria-Alisma Formation, 



(^/) Salix-discolor-lucida Formation (or the Cladium-Calamagrostis 

 Formation). 



There is comparatively little of the Potamogeton formation inside 

 of the old piles along shore, the water being for the most part quite 

 shallow, and the Scirpus-Typha formation taking up most of the area. 

 There is some indication of a change towards the Phrag?tiites-Typha 

 formation as the entrance to Niagara Pond is approached — some Zizania 

 making its appearance, but most of the zone is clearly to be referred 

 to the same formation which is to be seen in the nearby ponds and 

 lagoons, there being, however, more 7ypha. The habitat of this 

 formation is probably very little affected by the accumulation of humus 

 from the decay of the driftwood, and the protection afforded from the 

 active surf by the line of old piles makes the habitat very similar to 

 that of the recently formed ponds and lagoons along the northeastern 

 extremity of the peninsula. 



The Sagittaria-AlisDia Formation. 

 The character of this formation is chiefly determined by the ac- 

 cumulation of humus derived from the driftwood. The plants com- 

 posing this formation consist of species usually associated with rich 

 alluvial deposits of mud, the composition of the formation being essen- 

 tially as follows : 



