122 



BULLETIX 120, UNITED STATES NATIONAL, MUSEUM. 



diameter of resting nucleus 0.0108 mm.; cilia line interval, anterior 

 0.00183 mm., posterior 0.00375 mm. 



This is a very broad Zelleriella Avith nuclei much smaller than in 

 Z. macronucleata or Z. antUliensis. One finds an occasional daugh- 

 ter cell with narrower form and a well-defined posterior curved point. 

 In one such individual there were three very small nuclei (fig. 87, a), 

 apparently an abnormal conditions which might conceivably arise 

 in one of several ways not worth discussing without further data. 



ZELLERIELLA MICROCARYA, new species. 



Type. — United States National Museum Cat. No. 16485. 



Tlost. — Bufo lemur Cope, two abundant infections, in United States 



a c 



Fig. S8. — Zellekiblla miceocauya, X 460 diameters : o akd c show anteriorly 

 A portion of the linfs op insertion of cilia ; b is a daughter cell. 



National Museum specimens No. 27149 (the type infection) and No. 

 27150, each 73 mm. long, from Porto Kico, April 4, 1908; L. Stej- 

 neger, collector. 



Measurements of an ordinary individual. — Length of body 0.109 

 mm. ; width of body 0.074 mm. ; thickness of body 0.02 mm. ; diameter 

 of nucleus 0.00987 mm. ; diameter of endospherule 0.0015 mm. ; cilia 

 line interval, anterior 0.0017 mm., posterior 0.004 mm. 



This Zelleriella is of different form from Z. hufoxena. It is nar- 

 rower and is evenly rounded posteriorly except in the case of the 

 daughter cells from longitudinal fission, which in both species are 

 wedge-shaped with a round-pointed posterior end. Like Z. hufoxena 

 it has very small nuclei. Its nuclei are the smallest known among the 

 binucleated Opalinids, being but little larger than the largest nuclei 

 among the multinucleated species, as for example, Opalina cincta. 



