248 



WETZEL AND RICH 



TABLE 1 



RATES OF NET PRIMARY PRODUCTION OF PHYTOPLANKTON, 

 EPIPHYTIC ALGAE, AND MACROPHYTES, LAWRENCE LAKE, MICH. 



INCREASING FERTILITY 



Fig. 2 Relative primary productivity of emergent and submersed macrophytic 

 flora, attached and eulittoral (tychophytoplankton) algae, and phytoplankton 

 in lake ecosystems of increasing fertility. 



