BLACK COCKATOO. 
If these figures be averaged we would get Tasmanian average 371 mm., 
Victorian average 389 mm., Kangaroo Island 382 mm.. New South Wales 
average 420 mm., and King Island average 379 mm. 
It should be noted that one Victorian bird measures 428 mm. in the wing, 
and belongs to the New South Wales form. Unfortunately this particular 
specimen has no definite locality, but it almost certainly came from North 
Victoria. 
It will be at once seen that the averages do not agree with the facts as 
represented by the figures, yet this method of working was carried out in 
connection with Moluccan birds by Stresemann, and it is very easy to see the 
fallacy of it. Many American workers have also utilised this erroneous 
method, and having employed much paper and written detailed descriptions 
of the birds their fallacious conclusions have been ranked as valid until an 
independent worker checked them with other material. 
