, 



XLhc Botanical <Sa3ette 



B /fcontblE journal Bmbracing all Departments of ^Botanical Science 



Edited by John M. Coulter and Charles R. Barnes, with the assistance of other members of the 



botanical staff of the University of Chicago. 



-i 



Issued January 29, 1909 





I 



Vol. XLVII CONTENTS FOR JANUARY J 909 No. \ 



, ON TRIPLE HYBRIDS. Hugo de Fries - 



PERIODICITY IN SPIROGYRA. W. F. Copeland 



ON THE POLLEN OF MICROCACHRYS TETRAGONA (with plates i and ii). Robert 



Boyd Thomson ---- r - --------- 



A VEGETATIVE MUTANT, AND THE PRINCIPLE OF HOMOEOSIS IN PLANTS. 



Contributions from the Ames Botanical Laboratory No. 9 (with nineteen fig- 

 ures). Robert Greenleaf Leavitt 



BRIEFER ARTICLES 



Longevity of Seeds. William Crocker 



* 



Respiration Calorimeter. George /. Peirce - - - -• - - 

 Crataegus in Colorado. Francis Ramaley - 



CURRENT LITER A TURE 



1 



9 



26 



30 



68 

 71 



72 



BOOK REVIEWS ----- 



THE VEGETATION OF CHILE. THE PENDULATION THEORY 



74 



MINOR NOTICES 

 NOTES FOR STUDENTS 



75 





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