593 



Polypodiaceae 



1. Aspidiiim Thelypteris (L.) Sw. 



Mostly in the swamp meadow and outer parts of the reed 

 swamp; fairly frequent. 



2. Onoclea scnsibilis L. 



In the swamp meadow and reed swamp; rather rare. 



Bqnisetaceae 



3. Bqidsctum arvense L. . ; - 



In the meadow; frequent. / 



Typhaceae 



4. Typha latifolia L. 



In the reed swamp; abundant. 



Sparganiaceae 



5. Sparganium eurycarpum Engelm. 



In the reed swamp ; \tvy abundant, in many places almost 

 choking up the streams and ditches. In late summer, 191 1, after 

 the water in Skokie Stream had fairly well disappeared, great 

 quantities of young aerial shoots were put forth by this species 

 where it occurred upon the stream bed. When these shoots flow- 

 ered and fruited, they manifested a striking appearance, in that 

 they were yellowish green in color, — ^not dark green, as was the 

 species elsewhere (cf. Harshberger, '04, p. 136). 



Najadaceae 



6. Potainogeton sp. 



Potamogeton material was found in 191 1 in several of the 

 deeper places in Skokie Stream from the county line (Brae- 

 side) road as far north as to Lake Forest. This was not in fruit, 

 but appeared on careful comparison with herbarium specimens 

 to be P. zosterifoliiis. 



Alismaccae 



7. Sagiftaria latifolia Willd. 



Very common in the reed swamp and frequent in the swamp 

 meadow. Occasionally, detached stem-tubers from this species 

 were found being carried along slowly in Skokie Stream, indi- 

 cating that Sagittaria may at times migrate considerable dis- 

 tances in a purely vegetative way. 



