THE BIRDS OF AUSTRALIA. 
1789) ; this is based solely upon the Black-billed Tropic Bird of Latham, 
Syn. III., 2, p. 619, n. 2, which is thus described : “ This is in size 
smaller than any of the former ; length nineteen inches and a half. Bill 
three inches long, greatly compressed on the sides, and black ; the plumage 
on the upper part of the body and wings interruptedly striated black and 
white ; before the eye a large crescent of black ; behind it a streak of the 
same ; the fore-head and all the under-parts of the body pure white ; the 
quiUs and tail marked as the upper-parts, but the ends of the first white, 
and most of the feathers of the last marked with dusky black at the tips ; 
sides over the thighs striated black and white ; legs black. This was found 
at Turtle and Palmerston Islands, in the South Seas, and is in the possession 
of Sir Joseph Banks.” 
Under the next species, the Red-tailed Tropic Bird, Latham wrote 
(p. 621) : “ This species of Tropic Bird has been met with in several places 
of the South Seas ; very common at Palmerston and Turtle IslandsP 
This fixes the identity of Phoeton melanorJiynchos Gmelin as P. ruhricauda 
Boddaert, and P. mihereus Linne are apparently antagonistic and are never 
found together in the same breeding locality. Consequently P. melanorhynchos 
refers absolutely to the immature of P. ruhricauda. The name is older and 
would supersede P. novoehollandioe unless it were referable to another 
subspecies. We have no series from Turtle or Palmerston Islands, but 
specimens from the Society Islands, the nearest locality geographically, do 
not show the rosy red of the Kermadec birds and consequently the name, 
hke Pelecanus palmerstoni previously treated of, must be regarded as 
referring to an undefined subspecies until series are procured. 
It will have been noticed that Rothschild treated Laysan birds as 
typical P. ruhricauda^ and wrote of the Mauritius specimens as : “ These 
birds belong therefore clearly to the typical P. ruhricauda."*^ 
As a matter of fact, Mauritius is the type locality of P. ruhricauda^ and 
all comparisons must be based upon that fact. 
In the Austral Avian Record^ Vol. I., p. 88, 1912, I separated Phcethon 
ruhricauda westralis, subsp. nov., as differing from P. r. ruhricauda in its 
longer wing ; it also agreed in size with my specimens of P. r. eruhescens 
{novcehollandioe), but differed in lacking the depth of rose coloration apparent 
in those birds. My birds came from Rottnest Island, West Australia ; I 
would associate with them the Christmas Island (Indian Ocean) birds, as they 
fairly agree with the series available. 
My own criticism of the British Museum specimens shows that the bill 
of the Mauritius bird is practically the same as that of the Kermadec form, 
though the wing is noticeably shorter. 
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