L^^o-v*'*- ^ c '- 



" m ^ ^s\ . - < 1 i, * < 



f".':-.-"?^:.-' * >> .H-V3- 



5cm. 



-500ft,- 



i 



FIG. 366. Zonation about a pond 



I, pond ; II, bog zone ; III, swampy thicket zone ; IV, incomplete zone in arid soil 

 of a sand pit; V, dry meadow zone; VI, dry woodland zone ; o, floating mass 

 of Eriocaidon ; b, deepest area in pond, six to ten feet; c, association of tall 

 rushes (J-uncus milltaris) ; d, birch woodland (Betula populifolia) ; WE, line 

 intersecting formations of west side of pond; SN, line intersecting forma- 

 tions of north end of pond 



476 



