THE OPALIXID CILIATE INFUSORIANS. 191 



middle 0.05 mm., posterior 0.04 mm. ; diameter of micleus 0.003 mm. 

 to 0.004 mm. (dimensions of oval nuclei which se€m to be entering 



Fig. 159. — Opalina obtrigoxoidea maxima, from Bdfo halophilus, same individual 

 from which were taken the animals shown in figdeb 158. these two piguebs 

 together show the range of form and size in this one infection, x 117 

 diameters. 



on mitosis 0.0036 mm. by 0.0027 mm., 0.0045 mm. by 0.003 mm.) ; 

 eter of endospherule 0.002 mm. to 0.0022 mm. ; cilia line interv 

 terior 0.0018 mm. (second specimen 

 0.002 mm.), posterior 0.0028 mm. (the 

 second specimen 0.00375 mm.). 



This infection shows numerous broad 

 individuals and few, if any, so slender 

 as the usual O. ohtrigonoidea. The nu- 

 clei are small and mostly spherical, but 

 some are ellipsoidal, these seemingly 

 being about to enter upon mitosis. 



Opalina ohtrigonoidea lata^ United 

 States Xational Museum specimen Xo. 

 16564. 



Host. — Rana aesopus (Cope), one 

 very abundant infection, from United 

 States Xational Museum specimen 



diam- 

 al, an- 



FiG. 160. — Opalina obtrigonoidea 



LATA, FROM RANA ADROKA, X 117 

 DIAMETERS. 



No. 21703, 84 mm. lonff. 



from Crescent City, Florida, June 20, 1894; Henry G. Hubbard 

 collector. 



