THE OPALINID CILIATE IXFUSORIANS. 



205 



0.0048 mm. to 0.006 mm. ; diameter of endospherule 0.0015 mm. ; cilia 

 line interval, anterior 0.00158 mm., posterior 0.005 mm. 



These Opalinae grade into 0. virguloidea from other hosts and 

 can not be distinguished from them. 



Opalina virguloidea^ United States National Museum No. 16547. 



Host. — Hyla regilla Baird and Girard, one abundant infection, 

 from United States National Museum specimen No. 52321, 27 mm. 

 long, from Los Angeles County, California ; E. J. Brown, collector. 



Fig. 174. — Opalina virguloidea^ fbom Hyla begilla, X 117 diambtbbs. 



Measurements of two ordinary individuals- 



Measurements. 



Length of body 0. 29 



Width of body .077 



Thickness of body: 



Anterior 



Posterior 



Diameter of nucleus 0055-. 007 



Width and thickness of disk -shaped endospherule. . . 002 X • 001 



Second spherule 0025 X • 00125 



Cilia line interval: 



Anterior 



Middle 



Posterior 



tntn, 

 0.3 

 .111 



.018 

 .0205 

 0. 0053-. 0057 

 .00175 X .00125 



. 00195 



.0032 



.0035 



This infection in Hxjla regilla, from southern California, as com- 

 pared with infections in Hyla eximia from Mexico, gives quite a 

 different impression. The diversity of form is greater in the Cali- 

 fornia infections. Very few individuals show the exaggerated 

 comma-shape seen in almost all individuals of the Mexican infec- 

 tions. There are numerous slender individuals. But the measure- 

 ments of the California and the Mexican specimens agree, and those 

 of the California individuals which are comma-shaped agree closely 

 with the Mexican type. I am not attempting to distinguish the Call- 



