Genus— A MAURODEYAS. 
Amaurodryas Gould, Handb. Birds Austr., 
Vol. I., p. 286 (Sept. ?) Dec. 1865. 
Type (by monotypy) : . . . . Muscicapa vittata Quoy & Gaimard. 
Gould’s separative characters read : “ The well known Dusky Robin of 
Tasmania differs in several particulars from the true Petroicce, not only in 
colour, but in the stouter and more robust or thicker form of the bill ; its 
eggs are also very different from those of the Petroicce. The sexes are alike 
in colouring.” 
The plain colouring, large size and stout bill are diagnostic. As suggested 
in connection with the preceding, a critical examination of the osteology of 
this species from young to adult in comparison with that of other “ Petroicce ” 
might lead to an improvement in our knowledge of these peculiar Australian 
forms. The present species shows the speckled young of the others, but in 
this case though a larger size is noted, only a plain plumage in the adult has 
been attained. It is absolutely confined to Tasmania and the islands of Bass 
Straits, and appears to be represented on the mainland by the very distinct 
genus Melanodryas. Under that genus I have discussed this fact. 
In this genus, as is usual with sedentary island forms, though the size 
is increased, the wing has become more rounded, the first primary being half 
the length of the second, the second equal to the seventh, and neither 
much shorter than the intervening four, which are subequal and longest. The 
bill is long, narrowly triangular, the tip decurved, though bill all flattened, 
and the nostrils semi-operculate. The rictal bristles are strong. The feet 
comparatively longer and stouter than in the preceding, which otherwise 
agrees in size. 
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