POLYTELIS. 
and Pyrrhulopsis ; that is to say, to the Australasian forms described 
under the group Palceornithince. . . With the exception of Melopsittacus 
the whole group of Australian Parrots united under the name Platycercince 
agree, so far as I have examined them ... in several distinctive characters. 
The Australian genera Polytelis , Aprosmictus, and Pyrrhulopsis (and I expect 
Ptistes also) agree so perfectly in cranial characters with the Platycercince , 
that I do not doubt for a moment the necessity of removing them from the 
Palceornithince and uniting them with the other Australian genera.” 
With this evidence from the skeletal structure as to the affinities of the 
species and with the recognition of the presence of the furcula to contrast with 
it, I have separated these large species with family rank, a course which cannot 
be otherwise than adopted. 
It will be noticed that D’Arcy Thompson calls Pyrrhulopsis an Australian 
genus but this is not accurate. It is confined to the Fiji Islands and is so 
very closely related to the Australian Alisterus, that the type species of the 
latter was at its discovery considered a colour variety of the Fijian bird. 
The distribution of this family is very interesting from a phylogenetic 
view point, as it indicates that these species came from the north into Australia 
and that probably they are later immigrants than the Platycercine species 
though derived from the same stock. If we admit a southern origin for any 
Parrots we get the remnants in the genera Strigops, Pezoporus, Geopsittacus 
and Melopsittacus. The last seems so have recently evolved in a predatory 
manner, ousting the weaker forms which had more slowly evolved and become 
staid and unable to resist the more vigorous new comer. The small Neophema 
species have become almost extinct, but the larger species Platycercus are proof 
against the small Melopsittacus. While the Platycercus were developing in 
Australia another branch had pushed north into New Guinea and the Moluccas. 
The environmental stresses in these northern climes compelled th.e 
retention of the furcula, whereas the lesser stress of Australia allowed its dis- 
appearance. When this change had been completed the Northerners returned 
with the other migrants pushing southwards and travelled down the East of 
Australia and also along the North, reaching to the West, through the interior, 
but never penetrating into Tasmania. Pyrrhulopsis travelled eastwards to 
the limit of the continental area, surviving in Fiji. In this case there is slight 
superficial difference and with this appear small osteological differences while 
the coloration has undergone little change. This would suggest that coloration 
is a valuable item in this group and a factor that can be recognised in the 
genesis of groups. 
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