CELL STUDIES.^ 

 L SPINDLE FORMATION IN AGAVE. 



BY W. J. V. OSTERHOUT, 



Assistant Professor of Botany in the Unwersity of California. 



CONTENTS. 



Plates XXV-XXVIII. 



I. Introduction and Technique. 



II. Spindle Formation in Agave. 



Progenetic Stage. 

 Genetic Stage — 

 Stellar Stage — 

 Fascicular Stage 

 Bipolar Stage 



First Mitosis: ^^"^^^ 



261 



262 



265 



266 



266 



Second Mitosis: 



Introduction 



Progenetic Stage. 



Genetic Stage 



Stellar Stage 



267 



268 



268 



269 



Fascicular Stage ^7o 



Bipolar Stage ^^^ 



General Considerations ^7i 



274 



276 



278 



Summary 



Literature Cited 



Explanation of Plates. 



I. Introduction and Technique. 



Under this title I propose to publish the results of a 

 series of investigations bearing on various cell questions. 

 The especial attention which has been devoted to technique 

 in these investigations makes it desirable to refer at the 



1 Contributions from the Botanical Laboratories of the University of California. 



[ 255 ] April 30. 1902. 



