this information does not advance us one 
step towards clearing up the long contested 
point. It has long been known that males 
in the plumage of Mergus castor, or 
Dun Diver have been proved by dissection} 
and we have before been told that they pos- 
sessed a tracheal labyrinth similar to that 
of M^gus Merganser, or Goosander; but 
we should have been glad to have been 
informed whether in the trachea itself 
there had been one or two enlargements ; 
for otherwise we gain no additional 
knowledge/* 
He then gives a description (from Wil- 
lughby and others) of the trachea of the 
Goosander, and continues thus: " These 
appears to be incontestable facts of the 
trachea of the Goosander possessing two 
enlargements; now, as no naturalist has 
yet described such an appearance in any 
Merganser of different plumage, we are 
yet in the dark as to the immature male of 
this species, as well as the female." 
Such were the reasons given by an author 
of the first respectability, and whose opi- 
nions will deservedly continue to have a 
