THE OPALINID CIIJATE INFUSORIANS. 231 



Measurements: A^of a hroad individual; B, of a narrower form — 



Measurements. 



Length of body 



Width of body 



Thickness of body: 



Anterior 



Middle 



Posterior 



Diameter of nucleus 0. 0065- 



Diameter of endospherule 



Cilia line interval: 



Anterior 



Posterior 



0.235 

 .137 



.018 

 .0185 

 .016 

 0. 0062- . 008 



.0031 

 . 00337 



These infections present Opalinas of two shapes in the same host. 

 The broader forms are often greater in width than in length. Like 

 the form arvalis they are thinnest in front, though the difference i3 

 but slight. The narrower individuals are truncated behind and ir- 

 regular in contour, and, like 0. ranarum form truncata are thinnest 

 near this posterior edge. The very broad individuals in these infec- 

 tions are so characteristic that they deserve the forma name lata; 

 the narrower individuals seem to be the form truncata. 



Fig. 205.— Opalina raxardm smithi, X 117 diameters. The cili.\ted figure shows 



AN INDIVIDOAI, IN LONGITUDINAL FISSION. 



OPALINA RANARUM SMITHI, new subspecies. 



Type.— United States National Museum Cat. No. 16607. 



Eost.—Bufo smithi Stejneger, two infections, frou Kochi, Japan, 

 May, 1903; H. M. Smith collector. The type infection is from 

 United States National Museum specimen No. 31947, 64 mm. long. 



