58 BULLETIN 120, UNITED STATES NATIONAL MUSEUM. 



little beyond the anaphase, but still shows apparently six macro- 

 chromosomes somewhat irregularly arranged, evidently beginning 

 to pass into the metaphase condition. The form of the body is 

 shown in the figure. Its enlongated slender form suggests the 

 name given. 



PROTOOPALINA TENUIS (Raff). 



Opalina tenuis Kaff (1912). 



Hosts. — Crinia signifera Girard, two individuals from Australia, 



reported by Eaff, and two individuals from Australia, in the United 



States National Museum, Nos. 26411 (19 mm. long), and 26412 



(16 mjii. long), scant infection, both hosts collected by J. D. Ogilby ; 



a ^ c d 



Fig. 33. — Protoopalina tenuis. (After Raff.) 



also Vperoleia marrrwrata Gray [HyperoUus marmoratus Rapp], 

 from Narbethong, Australia, reported by Raff. 

 Raff's description in full, is as follows : 



Opalina tenuis, new species. This binucleated form was found in the large 

 intestine of two specimens of the brown froglet, Crinia signifera, one coming 

 from Narbethong, near Healesville, the other from Mentone, for both of which 

 my thanks are due to Miss O. B. Davies, B. Sc. I have also found it in another 

 small frog from Narbethong, which I take to be Hyperolia mannorata [Vpero- 

 leia marmorata Gray]. They were present in very large, numbers, and meas- 

 ured on an average 530m long and 36,1* broad. They present a very attenuated 

 or drawn-out appearance, and exhibit the usual corkscrewlike motion. The 

 cilia are very long and of much the same length all over the body, but at the 

 anterior end they are much more numerous and thickly arranged. The an- 

 terior nucleus is situated very near the front end of the body, while the 

 posterior one lies in about the middle of its length, or slightly in the posterior 

 half. In the younger and shorter forms the position of the anterior nucleus 

 varies, the individual represented in Fig. [33, o] having it situated further 

 down the body than is usual in the larger forms. This individual measured 

 215m in length. The smallest forms measured lOO/x in length. 0. tenuis oc- 



