INTRODUCTION. 5 



(Geotria) breeds in the fresh water, but the young go down to the sea 

 and reascend the rivers, while immature, in the spring, remaining 

 there to breed. Prototroctes breeds in fresh water, and probably 

 never goes to sea. The other species of Galaxias and Eleotris 

 remain in fresh water all their lives. 



The stationary portion forms the bulk of the fauna; and it 

 may be divided into a small aboriginal element, including species 

 which have no near relatives elsewhere, and larger Malayan, 

 Australian, and Antarctic elements, as well as several other smaller 

 ones. In many cases, however, it is hard to say in which group 

 a species should be placed, for its relations are so widely scattered. 

 Taking a broad view of the whole fauna, however, it may be said 

 that the terrestrial portion is chiefly of Malayan origin, but with 

 rather strong Palaearctic and Neo-tropical connections. The 

 fresh-water fishes and Crustacea are chiefly Australian and South 

 American, while the relations of the fresh-water mollusca are not 

 known to me. The marine fauna is chiefly Australian and 

 Antarctic. 



I will give a short account of each of these different ele- 

 ments. 



The Aboriginal Element. Includes the Short-tailed Bat 

 (Mystacops), the Tuatara (Sphenodon), and the Kiwi (Apteryx). 

 To which may be added the following birds : Glaucopis, Hetera- 

 locha, Turnagra, Xenicus, Stringops, and Nestor. Also the land 

 mollusk Carthea ; and the following among the insects : Onisci- 

 gaster, Orectognathes, Paradetis, Notoreas, Palccomicra, Mneo- 

 archtca, Arctoneura, Casa, Paradoxa, Opifex, Tinemyia, Frandator, 

 Ostenia, Exsul, Brounia, Camiarus, Epistranus, Cyphotelus, 

 Alema, Peneticus, Aphilon, Lore/us, Astetholes, Gastrosarus, and 

 others. It is not necessary to assume that all these aboriginals 

 date their arrival in New Zealand at the same time, for some may 

 have become modified more rapidly than others. But most of 

 them appear to belong to old forms, and probably they were 

 among the first comers. 



7 he Malayan and Melanesian Element. This embraces nearly 

 the whole of our land fauna, and a considerable portion of the 

 marine fauna as well. I should define it as including all those 

 species which have their nearest relatives in New Caledonia, New 

 Guinea, or the Malay Archipelago; and whose ancestors, pre- 

 sumably, came to New Zealand from the north. It includes all 

 the land birds except those just mentioned, and Zosterops all 



