vi] DISTRIBUTION OF SELECTED GROUPS 95 



Galaxiidae, a small freshwater family of trout- 

 and pike-like appearance. Galaxias, the main genus, 

 has become famous as one of the earliest and chief 

 supports of the former connexion of Australia with 

 South America. The same species, G. attemtatns, 

 inhabits the streams of New Zealand, Tasmania, 

 South Australia, the Falklands, South Patagonia and 

 Chile ; others occur at the southern end of America, 

 in Southern Australia, New Zealand and neighbouring 

 islands, and one at the Cape. One species (Chatham 

 islands), is said to be marine. The existence of a 

 species at the Cape would prove rather too much 

 for connexion vid Arctica, but, although it is not 

 impossible that these fishes are the remains of a 

 family which inhabited the southern shores of the 



V 



Great Gondwanaland, it is scarcely credible that 

 a species like G. attenuatns should have survived 

 since at least the Eocene. 



AMPHIBIANS. 



Amphibians cannot endure saltwater, nor can 

 they spread across deserts. Most abundant in the 

 tropics, they decrease rapidly towards the arctic 

 circle, their northern limit following roughly the 

 58th parallel in Eurasia and the 50th in America. 



The tailed amphibians, Urodela, are essentially 

 holarctic, with three main centres, European, Eastern 



