VoI 'i 924 IV ' J FALLA, Breeding of Buller's Shearwater. 
41 
offered very little resistance when removed from the egg. As we 
spent the remainder of the day examining typical burrows on 
the main northern island, the results of our observations generally 
will be best noted under the following heads:— 
Situation of Burrozvs .—Quite a wide range of burrowing sites 
had been chosen. While a few were found half a mile inland 
under roots of trees, the majority were in the cliffs and sloping 
seaward faces. In one place the flat cliff top, two hundred feet 
above the sea, consisting of sandy soil held together by a matted 
rush-like growth, was undermined with burrows opening from 
the top and running underground in all directions. Most of 
them were separate and averaged 3 feet 6 inches in length, but 
in some cases one tunnel was found to branch off inside into 
two nests. Elsewhere there was a number of short “runs” with 
two entrances, and in one of these a female bird was taken, but 
no egg found. 
/ he Nest. I his was placed, not at the extreme end of the 
burrow, but a short distance from it, leaving beyond a chamber 
large enough to enable the bird to turn round. A larger 
quantity of nesting material than is usual with most Shear¬ 
waters was used. Most of the nests contained two oy three 
handfuls of twigs, broken root fibres, and dead leaves. 
.~E,ach nest contained a single white egg, more or less 
stained by contact with the bird’s feet. Those examined varied 
somewhat in shape and size, but the majority were ovoid, tapering 
lather finely at the narrow end. The surface is smooth, some¬ 
times with a barely perceptible gloss, and is minutely and sparsely 
pitted. All these characters, however, appear to be variable both 
in presence and in intensity. Measurements of a series follow, the 
numbers referring to Plate: 
Egg No. 1. 65.0 mm. by 43.5 mm. 
2. 68.0 mm. by 43.6 mm. 
3. 61.5 mm. by 43.6 mm. 
4. 63.1 mm. by 41.5 mm. 
5. 66.0 mm. by 43.5 mm. 
6. 63.0 mm. by 41.5 mm. 
Incubation was well advanced, and each of the six eggs, 
representing several different localities on the island, contained 
an embryo at practically the same stage of development. In 
one nest, however, two eggs were found; one of these contained 
an embryo chick, and the other was quite fresh. 
Habits of the Bird .—Prior to this last visit to the Poor Knights 
the writer has had several opportunities of observing Buller’s 
Shearwater at sea between Auckland and North Cape. They 
are easily distinguishable both when on the wing and at rest, as 
their greater size separates them from the other white-breasted 
species found on this coast. The mode of flight varies with the 
weather. In a stiff breeze the birds appear to best advantage, 
sweeping in half-circles, and skimming the wave-tops, resembling 
