100 



that of tilt' inesophytic woods on tlie hike shore spoken of alvove. ami the 

 vegetation represents a higher type of niesophytie soeiety. 



In the evolution of the swamp of Turkey Lake, the first vegetation is 

 of water iilanTs. These are followed by bulrushes or sedges, and next 

 come shiubs and trees, in some eases those noted above, but in others 

 C'assandi'a calycidata wliich is followed by the tamarack (I.arix Am ri- 

 cana). Tliese swamps are destined to becmne forests, while in the ease 

 of the lake like Lake Cahimet. near Chicago, 111., the destiny of which 



Fig. 4. View of a portion of the beach in Cherry Creek Embayment. The slope is 

 gentle, rising from the low channel of the creek on the right to over 20 feet on the left. The 

 soil is very boggy and most of the bogs are associated with mineral springs. Rows of wil- 

 lows in the right center, with sycamores and oaks on left The rich nature of the soil is 

 apparent in the heavy herl>aceous vesfctation. Semi-fossili/ed l)ivalve shells were found 

 here. 



is the prairie, the liulrush stage is followed by gi-asses. It is suggested 

 by IM. Cowles tliat this ditterence in the ultimate development of the 

 swanip may be due to the depth of the kettle and consetiuently the depth 

 of the muck, the forest type being found by him to liave originated from 

 deep kettles and the prairie type from shallow ones. The muck in the 

 swamps ypoken of above is dee]) and their destiny is evidently forest, as 

 has been pointed out. but there is very little evidence of the Cassandra 

 and the Tamarack stages. There are a few tamarack swamps in the 



