INTRODUCTION. 7 



which have nearer relations in Australia or Tasmania than in any 

 other part of the world, and which we may suppose came to New 

 Zealand from the west. The Australian element in New Zealand 

 does not include any species connected with the ancient typical 

 Australian fauna, but is entirely made up of forms belonging to 

 the Malayan element in the Australian fauna which overran 

 Australia and Polynesia at a comparatively late date. 



We have, therefore, two possible explanations of our Australian 

 connection. Either (i) the ancestors of our animals crossed the 

 Tasman sea and so came to us from the west, or (2) the relation- 

 ship may be due to two branches of northern immigrants from 

 New Guinea, one taking the line to Australia, the other to New 

 Zealand. The first group forms the true Australian element, 

 while the second group ought properly to be placed with the 

 Malayan element ; but it is not always easy to say from which 

 direction the ancestors of our animals came. For example, the 

 marine spider, Uliodon maritima, was first found in New Zealand 

 and then in New South Wales, and was of course considered as 

 belonging to the Australian element, but it has lately been found 

 in New Caledonia. 



I should select as examples of the Australian element the 

 bat, Chalinolobus morio ; and among birds, Zosterops ccerulescens, 

 Hcematopus unite/or, and Spatula rhynchotis ; several marine 

 fishes, e.g., Arripis and Latris ; the land-shell, Laoma ; some 

 marine mollusca, like Megatebtnus ; some crabs, such as Parami- 

 thrax, Nectocarcinus, and Gzius truncatus. The fresh - water 

 isopod, Phreatoicus, and two or three land isopods ; beetles like 

 Pyronota, Adelium, Chrosis, and others ; several moths, and 

 perhaps the Land Planarians. Diporochceta, an earthworm from 

 the Chatham Islands, may perhaps be added, although it is far 

 more probable that these worms came to us by land from the 

 north. There are also several species of Myriapods common to 

 New Zealand and Australia or Tasmania, but these are easily 

 conveyed in fruit, and may be late introductions. 



When we consider that Tasmania and the South Island of 

 New Zealand are in the region of strong westerly winds, and that 

 gales are constantly traversing the Tasman Sea, we should expect 

 to find the Australian element much stronger than it really is. 



The Antarctic Element. These are the animals whose ancestors 

 we suppose came to New Zealand from the south or east, as we 

 find that their relations are confined to southern latitudes. It 



