FAUNA AND FLORA OF NEW ZEALAND. 15 
are cosmopolitan. Of a South American element we see no 
trace except it be in Nestor, which may be distantly related to 
the Macaws although still more nearly to the Brush-tongued 
Parrots of Australia and Polynesia. The Merganser of the 
Auckland Islands may represent the North Temperate element. 
The affinities of Zurnagra are still doubtful. I pointed out in 
1872* that our land birds had been derived from the north, and 
Mr. Wallace has subsequently, but quite independently, arrived 
at the same conclusion. While, however, Mr. Wallace thinks 
that the birds migrated along a land communication with 
Northern Australia in the cretaceous period, I was, and still am, 
of opinion that the fragmentary nature of our avifauna shews 
that the land was not continuous but was interrupted by an arm 
of the sea between New Caledonia and the main land, and further 
that this communication took place in the eocene and not in the 
cretaceous period. The remarkable fact that both our cuckoos 
migrate annually to New Zealand from Australia or Polynesia 
indicates, as I explained in my former paper, a much more 
recent northern extension of New Zealand, and this agrees with 
the evidence given by the flora of the Kermadec Islands. Mr. 
Wallace refuses to believe that these birds migrate, and thinks 
that they retire to some unexplored parts of the islands in the 
winter, but unfortunately he gives no hint as to where these un- 
explored parts are situated. 
Our lizards show an Australian element in J/ocoa and Hinulia, 
but the genus Wazltimus is endemic and belongs to a group of 
geckos found in Abyssinia, India, the Indian Archipelago, Aus- 
tralia and Chili. Sphenodon belongs to New Zealand only. Our 
single species of frog has decided South American affinities. 
Of the fresh-water fishes “/eotris is an Indian Archipelago 
and Australian genus, but as it is also found in Mexico and the 
West Indies it may possibly indicatea South American element, 
Galaxias, Cheimarrichthys (an endemic genus allied to Aphrites) 
Prototroctes,and the Lampreys are Antarctic; while the Eels are 
Australian or Polynesian. The marine fishes are a southward 
extension of the Indo-Pacific fauna, with a strong Antarctic 
element in Sovichthys, Notothenia, Thersites, Gonorhynchus, 
Callorhynchus, and perhaps in Genypterus and others. 
The land molluscan fauna appears to consist of Australian, 
Polynesian, and South American elements; the latter being 
marked by TZornatellina, Amphidoxa, Cyclotus, and perhaps 
Strobila. There is no Antarctic element. In my paper on the 
“Geographical Relations of the New Zealand Fauna” I stated 
that our fresh-water shells shewed a Polynesian affinity distinct 
from the Australian ; but in this I was mistaken, owing to my 
want of knowledge of the Australian fauna. It now appears 
that most of the genera are also Australian, but J/elanopsis is 
Polynesian, and Potamopyrgus is said to occur in South America . 
The affinities of our fresh-water limpet (Lata) are not known 
* Trans, N, Z, Institute, Vol. V,, pp. 251 and 252, 
