3i6 Proceedings. 



[abstract.] 



The author gave a short review of recent investigations on Rhizobia, 

 especially those of Hellriegel and Frank. Attention vy^as called to the ex- 

 isting controversies. It was suggested that there may be more than one 

 species of Rhisohkim leguniinsorarum notwithstanding the opposing views 

 of Frank and others who maintain that this is a single species. The fol- 

 lowing new species were described : Rhicobitim mutabilis, R. curvum, R. 

 Frankii var's, major and minor, R. nodosum, R. dubiiim. These were 

 placed in a new family, Mycodomatiae under Schizomycetes. R. mutabilis 

 is probably the most common among the Lcguminosae and above all others 

 has the power of assimilating free nitrogen from the air. Two plates ac- 

 companied the paper. 



''The sources of some of the constituents of Minnesota soils. '^ 

 Professor C. W. Hall. 



Dr. Charles N. Hewitt then read the paper of the evening- in 

 the form of a report of the section of Sanitary Science. Subject : 

 "Twenty years in the Public Health service of Minnesota." 



[The following papers are not arranged in chronological or- 

 der, as are those of Bulletins i and 2 of this volume, since at the 

 time of going to press several papers were in the hands of authors 

 for final revision. — Editor.! 



