I'^dS No. 43 



V 



/ 9 6)3^0. 44 



/9o3No. 45 



/^6 3 No. 46 



/f^SNo. 47 



/^^^No. 48 

 /•^^i/No. 49 



/^^t/_No. 50 



Some Correlations of Leaves, l:)y Daniel Trembly Mac- 



Dougal. 

 Soil Temperatures and Vegetation, by Daniel Trembly 



MacDougal. 

 Studies in Plant Hybrids : The Spermatogenesis of 



Hybrid Peas, by William Austin Cannon. 

 Some Aspects of Desert Vegetation, by Daniel Trembly 



MacDougal. 

 Anatomy and Physiology of Baccharis genistelloides, by 



Elsie M. Kupfer. 

 Mutation in Plants, by Daniel Trembly MacDougal. 

 The Polyporaceae of North America — VI. The Genus 



Polyporus, by William Alphonso Murrill. 

 The Spines of Fouquieria, by Winifred J. Robinson. 



