THE OPALINID CELIATE INFUSORIAISTS. 



223 



Rana esculauta, Linnaeus, rare, perhaps temporary infection; Tri- 

 turus alpestris (Laurent!), very rare. 



Ofdlina ranarum, United States National Museum No. 16593. 

 Host. — Rana teniporaria from Wiirzburg, Germany, May 7, 1907; 

 M. M. Metcalf, collector. 



Fig. 197. — Opalina raxakum^ from Rana te.mporaria : a, \ group of animals, showing 



RANGE OF FORM AND SIZE, X 117 DIAMETERS ; 5, A NUCLEUS X 4,100 DIAMETERS.' 



The central body in h, conventionally shaded, is the nucleolus. Two, or per- 

 haps THREE, OF THE DRAWINGS IN C SHOW INDIVIDUALS WITH IRREGULAR CONTOUR 

 AT THE POSTERIOR END OF THE BODY, INDICATING THAT THEY ARE ANTERIOR DAUGHTER 

 CELLS WHICH HAVE RECENTLY COME FROM TRANSVERSE FISSION. 



MeasureTnents: A, of alarge individv/il; 5, of a Tnedium-sized 

 indi/vidiuil,' 6', of a small, narrow individual — 



