UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



ZOOLOGY 



Vol. 16, No. 15, pp. 185-240, 58 figures in text March 16, 1916 



THE KINETONUCLEUS OP FLAGELLATES AND 

 THE BINUCLEAR THEORY OF HARTMANN 



BY 



OLIVE SWEZY 



CONTENTS 



PAGE 



A. Introduetion _ 185 



B. Historieal 187 



C. The oriler Binucleata 189 



I. The binuelear theory 190 



11. Critical discussion of the Binucleata 194 



1. The Haemoflagellata 195 



2. The Haemosporidia 201 



D. The parabasal body as a specialized structure 206 



I. Phylogenetic development 206 



1. First line — Haemoflagellata 209 



2. Second line — Bodonidae-Trichonymphidae 215 



II. Function and behavior 227 



III. Nuclear value not established by evidence 230 



IV. Use as a basis for classification not critically defensible 232 



E. Summary 234 



F. Literature cited 236 



INTRODUCTION 



The iiuieli discussed question of binuclearity among the Flagellata 

 has unfortunately depended for its answer upon the conditions found 

 among the smallest members of that group, which because of their 

 small size present peculiar difficulties to the investigator. Added to 

 the very great difficulty of working with organisms so near the limits 

 of microscopical vision, is the fact that, at the present time, no critical 

 stain for chromatin and chromatin alone has been found. 



All members of the so-called Binucleata are parasitic flagellates, 

 and in that fact lies another danger which has not been fully enough 

 appreciated. Parasitic forms, and this is especially true of those 



