TABLE OF CONTENTS 



PAGE 



Development of Pluteus admirabilis and Turbaria Jur- 



furacea (with plates I-V and eight figures) - - Leva B. Walker 1 



Development of root systems under dune conditions. 

 Contributions from the Hull Botanical Labora- 

 tory 250 (with seventeen figures) - - - - W.G. Waterman 22 



Some Phyllachoras from Porto Rico (with plates VI- 



VIII) - - - - - F. L. Stevens and Nora Dal by 54 



Apparatus for the study of photosynthesis and 



respiration (with one figure) . - - W. J. V. Osterhout 60 



A sporangiophoric Lepidophyte from the Carbon- 

 iferous (with plates IX-XI) - - . _ 



Intersexes in Plantago lanceolata (with plates XII, 

 XIII) 



Sexuality in Cunninghamella - - - - - 



Phytogeography of the eastern Mountain Front in 

 Colorado. I. Physical geography and distribu- 

 tion of vegetation. Contributions from the Hull 

 Botanical Laboratory 251 (with seventeen fig- 

 ures) ■ - - - Arthur G. Vestal 153 



On nitrification. III. The isolation and description 



of the nitrite ferment (with plate XIV) - - Augusta Bonazzi 194 



PolyxyHc stem of Cycas media. Contributions from 

 the Hull Botanical Laboratory 252 (with eleven 

 figures) - - Ward L.Miller 208 



A parasite of the tree fern {Cyathea) (with plates XV, 



XVI) F. L. Stevens and Nora Dalby 222 



Anatomy of Lycopodiuni reflexum (with five figures) - /. Ben Hill 226 



Origin and development of the pycnidium (with 



plates XVII-XXII) ------ F. E. Kempton 233 



'Ecology oi Tilia americana. I. Comparative studies 

 of the foUar transpiring power. Contributions 

 from the Hull Botanical Laboratory 253 (with 

 thirteen figures) James E. Cribbs 262 



