THE TUFTED POCHARD. 283 
But in the younger birds all these distinctions do not always 
hold good. Young Scaup often have a white chin, and very 
little, a mere speckling, of white at the base of the upper 
mandible ; and the young Tufted Ducks at times have the irides 
nearly white or brownish white, and have white about the face. 
The youngest specimens, however, of the Tufted Pochard that 
I have seen, have always exhibited the crest which characterizes 
the species, short no doubt, but of the peculiar linear feathers, 
so greatly developed in the old adult males; and this is the 
best practical diagnosis of doubtful birds of this species, 
though there are other differences in shape and colour of 
bills, &c. 
The White-eye and Scaup can be separated, J believe (but 
am not positive) at any age, by the colour of the irides, 
and certainly by the shape of the bills, which, age for age and 
sex for sex, are longer and broader in the Scaup, and less 
spatulate, ze, more of the same breadth throughout and 
less compressed or pinched in towards the base, than those of 
the White-eye. 
TRUE POCHARDS of the same types as some of those above 
dealt with occur throughout the world. The Canvas-back from 
North America I have already noticed, and there are other 
species from South America, South Africa, Australia and 
New Zealand. 
