Current Literature. 71 



Minnesota Trees and Shrubs: An Illustrated Manual of th£ 

 Native and Cultivated Woody Plants of the Staie. By F. E. 

 Clements, C. O Rosendahl, F. K. Butters. Report of the Botan- 

 ical Survey, IX. University of Minnesota, Minneapolis, Minn. 

 1912. Pp. 314. 



The present book is the ninth volume in the botanical series of 

 the publications' of the Geological and Natural History Survey 

 of the State, issued irregularly during the last twenty years. The 

 creditable standard of excellence which characterized the preced- 

 ing volumes is maintained in this issue. 



The text deals with 300 species and varieties belonging to 100 

 genera, arranged after the Besseyan sequence of families. It is 

 profusely illustrated, nearly all the species being figured. An in- 

 troduction of some twenty pages deals with the use of keys, 

 questions of nomenclature and phylogeny, and a brief discussion 

 of the vegetable types. This is followed by a key to the genera, 

 based on leaf and twig characters, and a flower key to the families. 

 In addition, a species key is given in connection with each genus. 

 The descriptive portion is very full, and notes are given as to 

 distribution, ornamental use, character and uses of wood, and 

 meaning of the scientific names. A generous glossary completes 

 the book. 



The paper, typography and binding are excellent. 



J. H. W. 



Nitrogenous Soil Constituents and their Bearing on Soil Fer- 

 tility. By Oswald Schreiner and J. J. Skinner. Bulletin 87, 

 Bureau of Soils, Dept. of Agriculture. Washington, D. C. 

 1912. Pp. 1-84. 



Progress of the U. S. Bureau of Soils in the study of organic 

 materials in the soil has been noted from time to time in this 

 journal (F. Q., Vol. IX, p. 99). Thirty-five such compounds 

 have now been isolated. Of these, thirteen are organic acids, 

 nine organic basic compounds, three carbo-hydrates, two alde- 

 hydes, two alcohols, one each hydro-carbon, glyceride, ester, sul- 

 phur compound, phosphorus compound and acid hydride. The 

 present bulletin, however, is concerned only with those organic 

 compounds containing nitrogen. Most of these are decompo- 



