OPALINID CILIATE INFUSORIANS METCALF 471 



nuclei are reported and tadpoles naturally infected would probably 

 show parasites of different ages, the older of which would be multi- 

 nucleate if the adults were Cepedea or Opalina. 



PROTOOPALINA [CAPENSIS, new species] 



Host: Heleophryne regis Hewitt. 



Through the Idndness of Dr. E. V. Cowdry I obtained two speci- 

 ments of this very rare and extremely interesting little frog, collected 

 by Dr. John E. Kex at Eastford, Krupna, Cape Province, South 

 Africa. They were preserved in formalin and after some weeks were 

 transferred to alcohol, not a satisfactory method of preservation, since 

 formalin allows deterioration of the opalinids. One frog, 44 mm. long, 

 now deposited in the U. S. National Museum as No. 67842, con- 

 tained numerous Protoopalinas, slenderly pointed behind and belong- 

 ing evidently to what I have described as the most archaic subgeneric 

 group of this most primitive genus. The other frog showed no 

 opalinids. 



Heleophryne was regarded by Hewitt as a leptodactylid, and such 

 it appears to be from its external appearance and its arciferous 

 shoulder girdle. But the leptodactylids are a family of southern 

 South American origin, which colonized Australasia, entering by way 

 of Antarctica. They are unknown in Africa except for Heleophryne, 

 which is represented there by only two species. Is Heleophryne a 

 true leptodactylid and, if so, how did it get from Patagonia to Africa? 

 In South America and Australasia the characteristic opalinid of the 

 Leptodactylidae is Zelleriella. If Heleophryne in South Africa carried 

 Zelleriella, an opalinid that was evolved in South America in the 

 Leptodactylidae and was carried wherever the Leptodactylidae have 

 spread, it would cUnch the evidence for the leptodactylid nature of 

 Heleophryne and its origin from South American ancestors. It was 

 this consideration that led Professor Cowdry to undertake to get for 

 me specimens of Heleophryne. 



Zelleriella was not found, but rather a species of a more archaic 

 group, representative of which are found in Patagonian and Australasian 

 leptodactylids, in Papuan Hylas, and in tropical African Pipidae 

 (Xenopodinae), and so the question of the origin and relationships of 

 Heleophryne is still open. Its parasite is consistent with Heleophryne's 

 origin from a South American leptodactyhd but does not clinch this 

 hypothesis as finding Zelleriella would have done. If such was the 

 origin of Heleophryne, the spread from Patagonia to Africa was later 

 than the origin of leptodactylids in Patagonia, and this was later 

 than the separation of Australasia from Asia in the early Cretaceous 

 period, probably considerably later. Interpretation of Heleophryne 

 as a leptodactyhd indicates connection between South America and 

 Africa at least as late as the middle Cretaceous period. 



