442 Capt. F. W. Hutton on the Origin of the 
quently, but quite independently, arrived at the same conclu- 
sion. 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 shows that the land 
was not continuous, but was interrupted by an arm of the 
sea between New Caledonia and the mainland, 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 Ker- 
madeec 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 unexplored parts are situated. 
Our lizards show an Australian element in Mocoa and 
Hinulia; but the genus Nauléinus is endemic and belongs to a 
group of geckos found in Abyssinia, India, the Indian arehi- 
pelago, Australia, and Chih. Sphenodon belongs to New 
Zealand only. Our single species of frog has decided South- 
American affinities. 
Of the freshwater fishes Hleotris is an Indian-archipelago 
and Australian genus, but as it is also found in Mexico and 
the West Indies it may possibly indicate a South-American 
element ; Galaxias, Chetmarrichthys (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 Bovichthys, Notothenia, 
Thersites, Gonorhynchus, Callorhynchus,and perhaps in Geny- 
pterus and others. 
The land molluscan fauna appears to consist of Australian, 
Polynesian, and South-American elements, the latter being 
marked by Zornatellina, 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 the freshwater shells showed 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 
Melanopsis is Polynesian, and Potamopyrgus is said to occur 
in South America, The affinities of our freshwater limpet 
(Latia) are not known. The marine Mollusca are, like the 
