OENCS PLYCTOLOPHUS. 
143 
The next primary division is that of the Cocka- 
toos, or subfamily Plyctolophina, Vigors, represent- 
ing the Kasorial Order, in the circle of the Psittacid®. 
It contains, besides the true Cockatoos, distinguished 
by their white or light coloured plumage, the vari- 
ous black or dark coloured birds belonging to the 
genus Calyptorynchus, Vigors, which we here desig- 
nate Geringores, a name given to some of the species 
by the natives of New Holland, in which interesting 
country they are chiefly met with. The birds of 
this division are among the largest of the Parrot 
tribe, and most of them, in a greater or less degree, 
are crested. The bill in the Geringore group, though 
short, and nearly concealed by the projecting fea- 
thers of the face, is remarkable for its strength and 
depth at the base. In addition to seeds, they are 
said to feed upon the roots of bulbous plants. In 
disposition, the birds of this subfamily are generally 
wilder and less tractable than many of the other 
groups of the Psittacid®. They breed in the holes 
of decayed trees, and their eggs are seldom more 
than two in number. The first group we have to 
notice is that of the genus Plyctolophus, Vieillot, 
of which the characters are: — Bill deep at the 
case, greatly arched and strong, the upper mandible 
forming nearly the fourth part of a circle, the tip 
