WHITE-THROATED SHAG. 
Are the adults with intermixed black and white under-surface the result 
of a cross between a black-bellied bird and melanoleucus ? Not of necessity 
I should think. 
Of the M. brevirostris in the British Museum there are three immature in 
the all-brown plumage, more or less glossed, and one like them with the chin 
white ; another with the chin white and the under-surface showing lighter; 
still another, immature in a further stage, has the under-surface of a pepper 
and salt colour. 
Then eight adults, with the chin and throat only white, all the rest being 
black ; another adult with the under-part of the neck white and the under¬ 
surface of the body with black feathers sprinkled through the white. 
Another albinistic form, as well as the under-surface, has most of the upper- 
surface, white ; the middle of the wing has a white patch, as most of the wing- 
coverts are white. 
The type of Plialacrocorax finschii Sharpe, Voy Erebus and Terror App., 
pt. xxn. (4 of birds), p. 34, April, 1876, New Zealand, has the entire under¬ 
surface white ; a narrow band of black running down the sides of the body, 
immediately below the wing ; upper-surface black, as is also a narrow band on 
the upper-surface of the neck ; forehead white ; a patch of white on the wing- 
owing to some of the wing-coverts being white, also a few white feathers amongst 
the scapulars, and is, I consider, a melanoleucus form of brevirostris . 
Thus we have a series connecting the specimens with the uncler-surface white, 
with the all-black bird with a white chin. 
Falla considers this to be a sub-species of melanoleucus and, as it is dimorphic, 
white-headed birds mate with the dark form and all connecting links of 
plumage are procurable. 
144 
