THE OPALIXID CILIATE INFUSORIANS. 



59 



curred along with O. intesthialis in Hyperolia marmorata, but in Crinia sig- 

 nifera it was the only species of Opalinu present. 



As noted above, I have had for study two infections of Protoo- 

 palina tenuis from Australian Crinia signifera. The measurements 

 of a full-sized individual are: — Length of body 0.2-1- mm= (too 

 much coiled to measure accurately) ; width of body 0.011 mm. ; 

 length of nucleus, first specimen 0.018 mm., second specimen 0.0195 

 mm., third specimen 0.024 mm. ; width of nucleus, first specimen 



I 



Fig. 34. — Pbotoopalina tenuis : a, an ordinary individual ; I), an anterior daughter 



CELL AFTER TRANSVERSE FISSION. X 460 DIAMETERS. 



0.0068 mm., second specimen 0.00975 mm., third specimen 0.012 

 mm. ; diameter of endospherule 0.002 mm. ; cilia line interval, anterior 

 0.0015 mm., posterior 0.00333 mm. 



The nuclei in most individuals are ellipsoidal and in almost a 

 reticulate condition with about 16 small chromatin masses. This 

 is not enough to determine that the number of massive chromosomes 

 is eight, but it indicates the probability of that number. In a few 

 instances nuclei apparently more spheriodal were seen, but the bodies 

 of these animals were much coiled and contorted and it may be 

 that the nuclei were seen partly in polar view. In one instance, only, 



