THE BIEDS OF AUSTRALIA. 
In the Monograph of the Petrels the family Puffinidce Procellariidce) 
is divided into two subfamilies— and Puhnarince, and in the former 
the genus Pterodroma (there called (Estrelata) is included. The apparent 
diagnostic characters used for separating Pterodroma and Puffinus are so slight, 
that it would seem reasonable to accept their close relationship. As a matter 
of fact, the members of the genus Pterodroma furnish a splendid example of 
convergence, as they prove essentially to be true Fulmars. They will con- 
stitute one of the most remarkable instances of the value of the study of young 
birds — a study which has been too long neglected by working ornithologists. 
As I have already pointed out, the nasal tubes in the genus Puffinus are developed 
independently on the sides of the culmen, and as the bird grows older the culmen- 
ridge becomes flattened, until the nostrils appear to lie on the top of the culmen 
Pterodroma.* Puffinus.* 
with a thick septum between. In the adult stage the bill of Pterodroma closely 
resembles that of Puffinus ^ but in the juvenile the nasal tubes are seen to already 
he on the culmen, and to be contained in a tube separated by a septum. In this 
matter they agree with Fulmarus and their much nearer alliance to that genus 
than to Puffinus cannot be denied. I concluded that there was no subfamily 
distinction available among the members of this family, judging from the 
adults, and certainly not that made use of by Godman in the Monograph of 
the Petrels. From further investigation it would seem that Puffinus is obviously 
well differentiated from Pterodroma and Fulmarus, and that it is probable 
Procellaria should be associated with Puffinus, while the other genera included 
in the Monograph in the subfamily Puffininoe should be attached to Pterodroma 
and Fulmarus. The members of the genus Pterodroma are known by the 
presence of their short stout bills which are always black, and by the coloration 
of their legs and feet. In the wholly-dark species these are wholly black, but 
in some cases these have light-coloured legs with only the outer half of the toes 
and webs dark ; this is the rule in all the other members of the genus. It is a 
remarkable fact that the general appearance of these birds has caused the recog- 
nition of a genus which at the present time seems well-constituted and compact, 
* The drawings of the downy young are made from specimens about the same age. 
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