422 BULLETIN 120, "UNITED STATES NATIONAL MUSEUM. 



Indies. Their Cepedeas are from Central America or western Brazil. 

 Their narrow Opalinas are from North and Central America, except 

 for the one species, ohtHgona, which has spread to Asia and Europe 

 and three (four?) derived and closely related species in Asia and 

 Abyssinia ( ?). The Hylidae are resistant to infection by Zelleriella, 

 for but three of the many species of Hyla examined are known to 

 have adopted these parasites, though the latter are abundant in the 

 habitat of the Hylas. They are known to carry Protoopalina only in 

 Australia, though they may be in contact in South America with a 

 species of Protoopalina closely related to the species which live in the 

 Australian Phdas. Also Hyla arborea^ of temperate Asia and Europe, 

 has come into contact with another species o'f Protoopalina similar to 

 one of the species found in an Australian Hyla. Some of the Central 

 American and North American Hylas live in the same region with 

 the genus Scaphiopus whose species bear the more highly evolved 

 members of the genus Protoopalina. The characteristic parasites of 

 the Hj^lidae are the Opalinae angustae. These are wholly Central 

 American and North American, except for the one migrant species 

 in Asia and Europe. America, especially tropical America, shows 

 the greatest development of the Hylidae, for it is here onl}^ that 

 most of the genera of the family are found, all but one of the genera 

 of Hylids being known from tropical America and only four of 

 these having any representatives outside this area. The only genus 

 of Hylid not found in tropical America is the eastern North Ameri- 

 can Acris. 



The Leptodactylidae bear Protoopalinas and Zelleriellas, but not 

 any of the multinucleated species. The Australian genera Limno- 

 dynastes and Uperoleia bear Protoopalina acuta., P. dorsalis^ P. 

 peronii, and P. " intefitinalis " which are archaic species. The Pata- 

 gonian Eleutherodactylus leptopus bears the closely similar Pro- 

 toopalina diplocarya. The Ecuadortan Tehnatohius jelsJdi bears 

 the quite distinct Protoopalina longinucleata. The long, slender 

 Protoopalina tenuis is found in the Australian genera CHnia and 

 Uperoleia. The Australian genus Limnodynastes and the tropical 

 American genera Eleutherodactylus., Leptodactylus^ Paludicola., and , 

 Telmatohius harbor Zelleriellae all so similar that species demarca- 

 tions in some cases are not easy to determine. The Leptodactylids 

 have not come much into contact with the multinucleated Opalinidae. 

 In America they are a tropical and south temperate family, while the 

 multinucleated Opalinidae, especially the Opalinas, are more north- 

 ern, but both Cepedea and Opalina are present in the more northern 

 parts of the habitat of the Leptodactylidae. Five Hylidae in Central 

 America harbor Opalinae., while three harbor Cepedeae. One Hyla 

 in Paraguay and one in northern Brazil carry Cepedea. We have 



