160 BULLETIN 120, UNITED STATES NATIONAL MUSEUM. 



Measurements. — Length of body 0.252 mm.; width of body 0.072 

 mm.; diameter of micleus 0.00775 mm.; diameter of endospherule 

 0.00225 mm. ; cilia line interval, anterior 0.00223 mm., middle 0.0036 

 mm., posterior 0.004 mm. 



This is a good-sized Cepedea shaped like a rather stocky C. 

 dimidiata. Its spherical nuclei are very large and its endospherules 

 also are large and spheroidal. Although this is a scant infection, 

 the few individuals found are of so distinct a sort that one does 

 not hesitate to assign them to a distinct species. 



CEPEDEA MEXICANA, new species. 



Ty^e.— United States National Museum Cat. No. 16502. 



Host. — Rana pipiens Schreber, one infection, from United States 

 National Museum specimen No. 3295, 72 mm. long, from Charco 

 Escondino, Matamoros, Tamaulipas, Mexico, March, 1853; Couch, 

 collector. 



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



Measurements. A \B 



mm. 



Length of body 0.217 



Width of body .06 



igth of nucleus j 'J^^^ 



Width of nucleus { '^^^7 



Cilia line interval: 



Anterior 



Posterior 



These Ceijedeas, after 65 years in the rectum of the preserved frog, 

 are in fair condition for study, though internal details of structure 



are not well seen. The body 

 form is shown in the figure. 

 The nuclei are distinctly 

 ellipsoidal, in many cases 

 being twice as long as broad. 



FlO. 128. CEPBDEA MEXICANA, X 460 DIAMETERS, rm t •.! .1 • i 



i hey lie with their long axes 

 in general parallel, or nearly parallel with the major axis of the 

 body. The cilia are short. The rather slender form of the body, 

 and especially the very small ellipsoidal nuclei are distinguishing 

 characters of this small Cepedea. 



CEPEDEA FORMOSAE, new species. 



Type. — United States National Museum Cat. No. 16523. 

 Host. — Bufo melanostictus Schneider, three infections ; one, scant, 

 from United States National Museum specimen No. 37511, from 



