THE OPALTNID CILIATE IIcrFUSORIAiSrS. 127 



caca, Peru, July 31. 1908. R. E. Coker. collector, and one scant infec- 

 tion from La Paz, Brazil. 



Measurements of an ordinary individual. — Length of body 0.1 mm. ; 

 width of body 0.0663 mm. ; thickness of body 0.0237 mm. ; length of 

 nucleus 0.016 mm. : width of nucleus 0.012 mm. ; length of endo- 

 spherule, smallest 0.0016 mm., largest 0.025 mm.; width of endo- 

 spherule, smallest 0.001 mm., largest 0.001 mm. ; cilia line interval, 

 anterior 0.0022 mm., posterior 0.0031 mm. 



The slightly ellipsoidal nuclei were seen in several instances to 

 contain f9ur chromatin masses seeming to be macrochromosomes. 

 Numerous cysts and a number of very small individuals were seen 

 in the type infection, but nuclei in the more elongated conditions of 

 mitosis Avere not observed. 



ZELLERIEIXA OPISTHOCARYA, new species (fig. 94). 



ry^e.— United States National Museum Cat. No. 16492. 



Host. — Bufo eonifenis Cope, three very scant infections, two from 

 Nicaragua, one. the type infection, from United States National 

 Museum specimen No. 29976, 39 mm. long, from Costa Rica ; Burg- 

 dorf and Schild, collectors. 



Measurements: A^of a large individual; B, of a small form — 



Characteristic of this ver}' large Zelleriella is the position of its 

 nuclei, far back in the body. The nuclei are slightly ellipsoidal, but 

 the material is not sufficiently well preserved to allow study of their 

 internal condition. 



ZELLERIELLA OPISTHOCARYA [of BUFO MONXIAE] new species (7) flig. 95). 



A specimen of this form has been deposited with the United States 

 National Museum as Cat. No. 16491. 



Host. — Bufo 7nmixiae Cope, two scant infections, one, the type 

 infection, from United States National Museum specimen No. 11358, 



