50 



BULLETIJT 120, UNITED STATES NATIONAL. MUSEUM. 



chromosomes. Its posterior, spine-like process is large and is 

 curved. The species seems sharply distinct, but it would be desir- 

 able to compare very fully numerous infections of this species and of 

 P. orientalis^ to be entirely sure that it does not intergrade with the 

 latter species as the broad caudata grades into the attenuate form. 



Fio. 25. — Protoopalina macrocaudata ; a, in the ordinary condition. X 460 diame- 

 ters ; h, IN AN anaphase of mitosis, X 1,000 diameters. 



PROTOOPALINA STEVENSONI, new name. 



This species was described, but not named, by Stevenson (1911). 



Host. — Bufo regularis, from Khartoum, Sudan. 



The measuremeiits taken froin Stevenson'' s figure of the largest 

 individual are as follows. — Length of body 0.08 mm. ; width of body 

 O.OG mm.; length of nucleus 0.013 mm.; width of nucleus 0.0077 mm. 



