NEW ZEALAND BROAD-BILLED PRION. 
a certain amount of white on the inner webs and dark shaft-streaks ; the long 
scapulars blackish tipped with white ; middle tail-feathers blue-grey like the back, 
with broad black tips which become obsolete on the outer feathers, the colour of which 
is paler ; the feathers of the crown are black subterminally ; base of forehead and lores 
whitish, like the supercihary streak ; throat, breast, abdomen and sides of body white 
hke the axillaries and under wing -coverts ; under tail-coverts white at base, the long 
ones blackish at the tips, the short coverts blue-grey like the lower flanks ; “ Upper 
bill, pale bluish-grey, shading into black at the base and on the nostrils, the central 
part of thecrdmen also black and the terminal part or point of the upper bill yellow. 
Mandible pale blue, with a black line along the centre of each side, and the tip black ; 
iris dark brown, legs and toes pale blue ; webs, flesh pink, with the free borders grey.” 
(Wilson.) Total length 300 mm. ; culmen (exp.) 33, wing 209, tail 104, tarsus, 33, 
width of bill 20. 
Adult female. Similar to the adult male. 
Nestling. “ The young taken out of the nest on the 20th November are clothed entirely 
with a dense covering of dark smoky grey, lightest on the neck and under-surface ; 
pectinations of the upper mandible undeveloped ; the bill measures from gape to point 
1 inch, greatest width only 4 lines ” (Potts). 
Nest. “ At the end of a straight burrow, which dips sHghtly for eighteen to twenty -four 
inches. Or in the cavities of the cliffs on the sea-shore ” (Travers). 
Egg. Clutch, one; pure white, glossless and minutely pitted; axis 48.5, diameter 35 
(Chatham Islands). 
Breeding-season. September (Travers, Chatham Islands). 
Erom Mr. Travers’s notes* I gather that both sexes take part in the incuba- 
tion, during which time they are not easily disturbed, simply pecking at the hand 
when the egg is being taken, but remaining on the nest after its removal. 
When taken from the burrows in the day-time and liberated, they fly away 
with a wavy uncertain flight as if blinded by the sudden light. When the egg 
is laid in the crevice of the cliffs, it is placed on the bare rock, but when laid 
in the burrow a few leaves are placed under it. 
Dr. Wilsonf gives a most interesting account of the formation of the 
“ pouch,” in the lower mandible of this bird. “We obtained one or two 
specimens on the ‘ Discovery,’ and were much interested to And that the 
floor of the mouth was very extensile, enabling it to take up a much larger 
quantity of water and small crustaceans than would otherwise be possible. 
If the lower bill of a dried skin is examined the loose blue [in life] skin between 
the rami of the lower jaw will be found dry and folded to form a hard level 
floor to the mouth. But if the tip of the little Anger is inserted into the mouth 
of a freshly killed specimen, it wiU be found that the neatly folded skin' can be 
quite easily distended into the form of a bag, or sack, something like that of the 
pehcan, which is obviously of use to a bird that has developed lameUse on the 
upper bill which act like the baleen plates of a whale. The tongue is bright, 
* Trans. New Zealand Inst. 1872, Vol. V., p. 220, 1873. 
f Nat. Antarct. Exp., Aves., p. 104, 1907. 
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