Che Botanical Gazette 
A Montbly Fournal Embracing all Departments of Botanical Science 
4 d ay JoHN M. CouLTER and CHARLES R. BARNES, with the “ae eee of other members of the 
q botanical staff of the University of Chi 
Issued December 18, 1909 
XLVIII CONTENTS FOR DECEMBER 1909 No. 6 
ON SPINULOSUM. ConTRIBUTIONS FROM THE saga BOTANICAL LABORATORY 131 ne 
_ SEVEN FIGURES). Charles]. Chamberlain ~ 
3 INFLUENCE OF GRAVITY ON. THE DIRECTION C OF este. OF aassea ak oe 
| (WITH THIRTEEN FiGuRES). Stella G. Streeter - 
E WILLIAMSONIAS OF THE MIXTECA ALTA (WITH TEN FIGURES). G. R. Wieland - 427 
| IN ay BIBER seers Senkie FIVE ee Hf, E. Merwin and Howard 
4 © = = pe - 442 
EFER ARTICLES 
CONCAVITY OF LEAVES AND ILLUMINATION pres ONE ee Joseph Y. Bergen - 459 
3 ROEZL AND THE TYPE OF WASHINGTONIA. S. &. Parish Site - - - 462 
| Loncevity or SeEeps. Alfred J: Meer cn sace gate Seis oe ee 
| REjoinpER. William Crocker - - - - - Be ee tie Rees eek 
RRENT LITERATURE 
» MINOR NOTICE eh in ert 2 te Mat octal ene Tee al aetna eer 
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