994 MINNESOTA BOTANICAL STUDIES. 



from its original place of development, it seems more reason- 

 able to include the anchored bogs under the second category. 



Morasses are generally either peaty in structure or formed 

 of grasses and sedges. The peat morass, so far as my obser- 

 vations go, is not developed at Lake of the Woods as an along 

 shore formation though it occurs thus situated in some of the 

 smaller ponds of the back-country. I therefore judge that in 

 all probability such peat marginal formations will be found in 

 some of the secluded bays of the main lake. The peat shore 

 population as I first showed in a paper published in 1894 8 may 

 under certain special conditions give rise to the singular for- 

 mations named " Sphagnum atolls." None of these have been 

 seen in the Lake of the Woods region, although they may pos- 

 sibly occur, and have readily escaped observation. Where 

 morass is found as a shore formation on this lake it is gener- 

 ally of the gramineous or cyperaceous variety. 



Morass does not face exposed sheets of water, but is con- 

 fined to the narrower bays and coves where surf can not easily 

 be formed, for there is little wind, and upon shelving banks 

 rather than upon precipitous. As a consequence I have not 

 found the formation facing either the Grand Traverse or the 

 Little Traverse, but in such regions of the lake as the west 

 shore of Flag island, the east shore of Oak point and the sinuo- 

 sities of MacPherson's bay it is a conspicuous shore-type, and 

 may be classified generally into the two main groups of attached 

 morass and detached morass as indicated above. Of attached 

 morass two types are recognized, wet and dry. The former is 

 loose and spongy and will not bear one's weight upon it, the 

 second is firm and in its different varieties will always support 

 one walking upon it. The different types may be examined 

 seriatim. 



Wet morass. An example of this in Echo bay, near Rat 

 Portage, is shown in Plate LXXVI. Here it consists of two 

 well marked zones, an outer one of Scirpus and an inner one of 

 Salix. But these are by no means always the characteristic 

 types. As varieties of wet morass the following may be named. 



I. Gramineous morass. The characteristic plants are 

 grasses and the basis of the formation originates from the 

 interlocked, tangled rhizomes and roots of these plants. In 

 some cases Phragmites is the principal plant, in others Zizania, 

 in still others Panicularia, Of the three kinds that formed by 



8. MacMillan. On the occurrence of Sphagnum Atolls in Minnesota. Minn. Bot 

 Stud. 1: 2-13. 1694. 



