Opalina. 249 
somes in metazoan nuclei. It seems more probable that the equa- 
torial chromatin ring in O. satwrnalis is comparable to a chromatin 
nucleolus. It seems impossible that its division can be equivalent 
to the splitting of the chromosomes in Metazoa. I have not yet 
examined nuclei of O. saturnalis and cannot interpret the nuclear 
conditions in this species in comparison with those described for 
O. intestinalis and O. caudata. It may be that the equatorial band 
A (i) Bir C (1) D (15) 
fi i) y 
it y 
We Ra 
te F (17} G8) Hi1s) 
Text Fig. IV. Mitosis in O. saturnalis. After Licer & Dusoscg. The numbers 
in parentheses are their figure numbers. >< 1500 diameters. 
of chromatin in O. saturnalis is homologons with the irregular ring 
of chromatin in daughter nuclei of O. intestinalis and O. caudata 
formed by the fusion of the chromosomes, as described, preceeding 
the formation of the chromatin ribbon (spireme). In multinucleated 
species and in O. macronucleata (BrEzzENBERGER 1904) much of the 
chromatin often gathers in one or more large masses beneath the 
nuclear membrane (Figs. 99—101, Pl. XXI, and Text Fig. V, a). It 
‘is possible that these superficial chromatin masses correspond to the 
equatorial band in O. saturnalis. 
BezzeENsBeERGER has described for the binucleated O. macronucleata 
