THE OPALINID CILIATE INFUSOEIANS. 



33 



The general significance of this peculiar mitotic condition -will be 

 discussed later in this paper. 



Awerinzew's description of his animals is not illustrated and 

 measurements are not given. It is therefore not possible to make 

 satisfactory taxonomic comparisons with other species. It is, how- 

 ever, evidently a distinct species, having its nucleus characteristically 

 in an earlier mitotic condition than is the case in Protoopalina 

 diflocarija which seems to be the species whose nuclei most 

 resemble those of P. primordialis. 



PROTOOPALINA DIPLOCARYA, new species. 



Type.— {Jnit^d States National Museum Cat. No. 16428. 

 Bost.—EleutherodacUjlus leptopus (Bell). Cat. No. 15125 of the 

 collections of the United States National Museum; from Mayne 



Fig. 11. — Protoopalina diplocakya ; an optical, longitudinal section. X 460 



DIAMBTERS. 



Harbor, Patagonia, collected February 5, 1877; length of individual 

 host, 22 millimeters. 



But one specimen of the host was available. This had already been 

 dissected. In its rectum was found an abundant infection of well- 

 preserved Protoopalinas. 



Measurements of an ordinary individual. — Length of body 

 0.217 mm. ; greatest width of body 0.0413 mm. ; thiclmess of body at 

 same level 0.038 mm.; diameter of nucleus 0.013 mm.; diameter of 

 endoplasmic spherules 0.002 mm.; width of average interval be- 

 tween the lines of cilia, at the anterior end of the body 0.00125 mm., 

 near the posterior end of the body 0.0035 mm. 



The lance form of the body and th^ very long cilia are shown in 

 figure 11. The whole body is clothed with cilia except the acuminate, 

 often spinelike, posterior tip, which is naked. The cilia are three times 

 more numerous over the anterior quarter of the body, a fact not 

 shown in the figure. The ectosarc is quite thick and is more coarsely 

 alveolated than the endosarc, a fact not shown in the figure. There 



