chap, xin.] THE AUSTRALIAN REGION. 397 



while a much smaller number are confined to the East and 

 South-East, or to the North. 



Among the fresh-water turtles of the family Chelydidse 

 there are three peculiar genera — Chelodina, Chelemys, and Mseya, 

 all from Australia. 



Amphibia. — No tailed amphibians are known from the whole 

 region, but no less than eleven of the families of tail-less Batra- 

 chians (toads and frogs) are known to inhabit some part or 

 other of it. A peculiar family (Xenorhinidae), consisting of 

 a single species, is found in New Guinea; the true toads 

 (Bufonidse) are only represented by a single species of a pecu- 

 liar genus in Australia, and by a Bufo in Celebes. Nine of the 

 families are represented in Australia itself, and the following 

 genera are peculiar to it : — Pseudophryne (Phryniscidae), Pachy- 

 batrachus, and Chelydobatrachus (Engystomydae) ; Helioporus 

 (Alytidae) ; Pelodyras and Chirodyras (Pelodryadae) ; Notaden 

 (Bufonidse). 



Fresh-water Fish. — There is only one peculiar family of fresh- * 

 water fishes in this region — the Gadopsidre — represented by a 

 single genus and species. The other species of Australia belong 

 to the families Trachinidge, Atherinidae, Mugillidae, Siluridse, 

 Homalopterae, Haplochitonidae, Galaxidae, Osteoglossidae, Sym- 

 branchidae, and Sirenoidei ; most of the genera being peculiar. 

 The large and widely-distributed families, Cyprinodontidaa and 

 Cyprinidae, are absent. The most remarkable fish is the recently 

 discovered Ceratodus, allied to the Lepidosiren of Tropical 

 America, and Protopterus of Tropical Africa, the three species 

 constituting the Sub-class Dipnoi, remains of which have been 

 found fossil in the Triassic formation. 



Summary of Australian Vertebrata. — In order to complete 

 our general sketch of Australian zoology, and to afford materials 

 for comparison with other regions, we will here summarize the 

 distribution of Vertebrata in the entire Australian region, as 

 given in detail in the tables at the end of this chapter. When 

 an undoubted Oriental family or genus extends to Celebes only 

 we do not count it as belonging to the Australian region, that 

 island being so very anomalous and intermediate in character. 



