326 
Mr. P. R. Lowe on Birds collected 
grows among the boulders amidst which they were breeding. 
The nests on this island were raised some little way off 
the ground, and rested, as a rule, on the centre of a thick 
tussock of loug grass or on some low spreading shrub. 
We found none until we had reached an altitude of about 
three or four hundred feet, and the birds chose ground of 
the roughest and rockiest description, so that they were 
partly hidden among boulders, long grass, and cactus. 
Only one egg appears to be laid. The young bird when 
hatched is naked. The parent birds were astonishingly 
tame and confiding. 
The commonest form of plumage which we noticed was 
that in which the head, neck, nape, and back were all black, 
relieved by a beautiful greenish-purple sheen, the throat 
and thorax being white. Next came a form in which the head, 
neck, nape, and breast were entirely white; while infinitely the 
rarest variety was that in which the head and neck were 
black, but the throat exhibited the conspicuous and remark¬ 
able red gular pouch. The first stage consists apparently of 
both young males and females, the next of older females, 
and the last of old males. I saw all three varieties 
incubating. 
So far as I have been able to observe, it is only the fully 
adult male that exhibits the extraordinary balloon-shaped 
pouch, which it can distend at will. I, however, noticed 
some birds, apparently not fully -adult males, with orange 
gular sacs, and some, apparently still younger males, with 
the white throat and breast, mottled and streaked with 
black, in a stage antecedent to the perfectly fully-adult male. 
These appeared to have no distens ; ble gular sac, or at any 
rate it was not apparent. The fully-adult males were very 
shy, and I could not get near enough to take photographs of 
the few I found sitting on nests. As we reached the top of 
the island (650 ft.), some of these old males were soaring 
against the strong trade-wind just above our heads. The 
vivid red, almost translucent, and distended pouch waggled 
about in the breeze in a somewhat ludicrous way. It 
appears to have a constricted and elongated neck, which 
