Vi CONTENTS 
SHULL, GEORGE Harrison. The duplication of a leaf-lobe factor 
in@enhe shepiterd.s-pUEse j.'s. e.0e Ja ee eee eee eee 427 
SINNOTT, EDMUND W. Isolation and specific change.......... 444 
SmitH, Erwin F. .The relations of crown-gall to other over- 
SLOWENS tm plants. 2+. ea ee ee ee 448 
Srone, GEORGE =, Contact stimulation. =... .9 40.) eee 454 
Strout, A. B. Duplication and cohesion in the main axis in 
CLEMOT UI TMV OUS 7s bys «RAR oe Se 480 
TayLor, NorMAN. A quantitative study of Raunkiaer’s growth- 
forms as illustrated by the 400 commonest species of Long 
slamel IN eVect i eer erent Gn ba ie ee 486 
TRELEASE, WILLIAM... Dhe-ancient oaks) ot America. .2 2 oeeer 492 
TRruE, RopNEy H., and HArvey, R. B. The absorption of cal- 
cium: salts by«squasi, seed linc, ar deter ie: ate 502 
WHITE, ORLAND E. Inheritance studies on castor beans....... 51 
