PLATE I. 



Sium ciciilue/oliuiii (jiiit-l. A jar <il secdIiiiKS, piioto^^raplied at llie University 

 of Chicago, Octolier lo, 1903, by Ur. W. J. G. Land ; spring-growtii of an old 

 plant, piiotograpried at Lockport, ill., May 16, 1903, by W. E. Praeger ; and a 

 flowering-stem piiotograplied at South Cliicago, September 22, 1903. 



