70 Proceedings of the Ohio State Academy of Science. 



tallest of which is 30 inches, and a clump of Decodon 

 verticillatus at the water's edge. Back from the margin, 

 the shruhs Alnus and Rhus, become more frequent, the 

 Typha being confined to the more open water of the 

 pools. There is a scattering growth of marsh herbs as Comarum 

 palustre, Triadenum virginicum ; Bidens tricosperma and B. 

 discoidea at the base of the shrubs and on the stalks of the Typha, 

 Impatiens biflora, Viola blanda often in the shallow water, Cicuta 

 bulbifera and Dryopteris thelypteris. There is an entire absence 

 of a sedge zone, the sedges being confined to one small clump of 

 Carex interior. 



A well defined stratification or layering is represented by the 

 following species : / ' 



1. Rhus vernix-Alnus rugosa rising to a 'height of 12-15 

 feet. IMany of these are in a half dead condition and there is 

 also much dead timber. 



2. Typha latifolia, thrifty plants in fruit and 6-7 feet tall. 



3. Rosa Carolina, a few shrubs at a height of 4-5 feet. 

 Rumex brittanica. Hibiscus moscheutos, all at maturity as tall 

 as the Rosa. 



4. Low shrubs from 2-4 feet tall, Cephalanthus occidentalis, 

 Decodon verticillatus, Solanum dulcamara. 



5. Herbs. The height which these herbs attain varies of 

 course with the season, at maturity they are from 1-2 feet tall. 

 Comarum palustre, Bidens tricosperma, B. discoidea, Impatiens 

 biflora, Carex interior, Triadenum virginicum, Cicuta bulbifera, 

 Peltandra virginica and Roripa americana. 



6. Ground cover. A'iola blanda, Aulocomnium palustre, 

 Sphagnum acutifolium, S. cymbi folium and seedling Acer and 

 Rhus which are abundant near the outer portion of the zone. 



HL Bog-thicket association: This covers a belt 18 feet 

 wide on the western and 20 feet on the eastern border. The 

 water level is high, the surface a succession of hummocks sepa- 

 rated by a labyrinth of small irregular waterways with an average 

 depth of 3 inches. The zone is characterized by a Rhus-Alnus 

 society, with Rhus vernix and Alnus rugosa the dominant species. 



