THE OPALINID CILIATE INFUSOKIANS. 



47 



to four times as thick (figs. 22, A, and 23). They must have 10 to 15 

 times the bulk of the slender forms. These swollen individuals prob- 

 ably belong to the species P. nutti and are probably comparable to the 



Flo. iJ2A. — Protoopalixa ndtti, large individuals, apparently abnormal ; X 460 



DIAMETERS. 



greatly enlarged individuals of P. caudata sometimes found. These 

 large individuals of P. nutti resemble the slender individuals in hav- 

 ing a thick ectosarc and in having the perinuclear vacuoles well de- 



FiG. 23. — Pkotoopalina ndtti, stocky form. The nuclei of this and other stocky 

 individuals seem abnormal. x 4g0 diameters. the anterior end is to the 

 left. 



veloped. The cilia are apparently of the same length. Though 

 the body is so stocky, some individuals show slight but definite indi- 

 cation of a posterior point which, as in the slender forms, is not 

 sharp but rounded at the tip. 



