332 J. H. POWERS AND CLAUDE MITCHELL. 



EXPLANATION OF PLATE I. 



Parameciiim multiinicronucleata. 



FIG. i. Conjugation near the three-hour stage, showing micronuclei in pairs 

 or in division. 



FIG. 2. Conjugation at about seventeen hours. Macronucleus already broken 

 into band-like portions. Micronuclei visible in part, in pairs or single. 



FIG. 3. Section of typical P. miiltimicronucleata, an unusual number of the 

 micronuclei chancing to lie in one plane. 



