432 Evolution and Distribution of Fishes 



Before attempting any decision we may first try to secure 

 collateral evidence. The next — though a small — family to 

 the Galaxidae is the Aplochitonidae, and both of these ex- 

 hibit decided affinity with the Esocidae, the Cyprinodon- 

 tidae, Amblyopsidae, and Percopsidae that are freshwater, 

 also the Enchodontidae — an extinct marine cretaceous fami- 

 ly, — the Scopelidae, and two other smaller highly modified 

 marine families. The geographical distribution of the 

 Aplochitonidae is as arresting as is that of the Galaxidae. 

 For of the two included genera Aplochiton {Haplochiton 

 of some systematists) is made up of two species found in S. 

 Chile, Tierra del Fuego and the Falkland Islands, while 

 Prototroctes has one species In N. Zealand, one in S. 

 Australia, and one In Queensland. 



So the much discussed question of a possible geologic 

 connection between Patagonia, N. Zealand, Tasmania and 

 Australia, possibly also the Cape of Good Hope, Is present- 

 ed. We need not here review all of the alternative sugges- 

 tions made. But before treating of the above two families, 

 and of facts both from the botanical and the zoological 

 sides that may greatly aid in reaching a correct decision, 

 we may give attention to the Symbranchldae and Amphi- 

 pnoidae. 



One genus Chilohranchiis Includes a species native to 

 Tasmania, and another to N. W. Australia. Symbranchus 

 Includes a species that extends from Mexico to the rivers 

 of S. Brazil. Now at first sight such might favor the form- 

 er existence of a wide southern bridge from eastern S. 

 America to Tasmania. But the distribution of the remain- 

 der causes the Symbranchldae to resemble, and the allied 

 Amphipnoidae to fall In with, other large groups whose 

 past geologic expansion we have already considered. For 

 two species of Symbranchus extend from the Hoogly to the 

 East Indian Archipelago, the single species of Amphipnous 

 inhabits the rivers and brakish w'aters of India and Burmah; 

 while Monopteriis extends from Malaya to S. China and 

 Japan. 



A quite natural and continuous interpretation here 

 would be that both families evolved either In eastern Brazil 

 or In Africa, and In the former case migrated eastward 



