38 On the Geographical Relations of the New-Zealand Fauna. 



we have positive evidence that our ishinds can even now be 

 colonized from Australia by many kinds of bu-ds, although 

 1400 miles distant. It would also appear that this transfer 

 of birds to Xew Zealand took place sufficiently long ago to 

 allow of changes of generic value having taken place, while 

 the Chatham and Auckland Islands have been isolated from 

 New Zealand for a time sufficient only for changes of specific 

 value. 



Reptilia. 



The Reptiles of New Zealand are not numerous. We 

 possess about eight species of lizards, four of which belong to 

 widely spread genera of tlie family Scincidee ; but the species 

 are all endemic. Three others belong to the Geckotidge, and 

 form a genus {Naultinus) which is found nowhere else. Of 

 these, one {X. pacificns) is said to be found in some of the 

 Pacific islands ; but the other two are peculiar to New Zealand. 

 Our eighth species, the curious tuatara [Sphenodon inLnctatum) ^ 

 which is now found only on a few rocky islets in the Bay of 

 Plenty and near Toiy Channel in Cook's Strait, is placed by 

 Dr. Giinther in a separate order from all other lizards on 

 account of the affinity that it shows to the crocodiles. This 

 remarkable form has no copulatory organs, and has micinate 

 processes on its ribs like birds. It has also nearly twice as 

 many abdominal as true ribs, which protect the abdomen when 

 being dragged along the gi-ound, for, as in the crocodile, the 

 hind legs are too weak to support the hinder parts of the body ; 

 Dr. Giinther also suggests that they may use these ribs for loco- 

 motion as snakes do. It is also remarkable that this animal, 

 which lives in holes and only comes out during warm weather, 

 should have the dorsal crest that is so characteristic of tree- 

 lizards. 



I omit all reference to Norhea ? isolata^ supposed to come 

 from White Island in the Bay of Plenty, because its true 

 locality is not sufficiently well established ; if, however, 

 another specimen should be obtained, it would be most im- 

 portant evidence in the present discussion. 



But one species of lizard is found on the Chatham Islands, 

 which is very variable, but which I consider to belong to the 

 species Mocoa zelandica ; it is, however, larger, and shows 

 some slight ditferences in the shape of its cephalic shields. 



A ringed sea-snake, probably Platurus scutatus of Australia 

 and Polynesia, is sometimes washed alive on to our coasts as 

 far south as the mouth of the river Waikato, but it is not yet 

 ascertained whether it is an inhabitant of om- seas. A peculiar 

 variety of Pelamis hicolor^ which as yet has not been found in 

 any other locality, has also been taken on our shores. 



