116 ZOOLOGICAL EXERCISES, 
and Dasornis and Gastornis of the eocene period in Europe, appear to be 
intermediate between the Dinornithide and the Casuaride. 
Carinatz. Cervical vertebree without trans- 
verse process ; sternum with a keel, and usually 
five centres of ossification, one of which is 
median in the keel; scapula forming an acute 
or slightly obtuse angle with the coracoid ; 
vomer small; barbs of the feathers usually 
with barbules. : 
There are twelve orders: 
Passeres. Toes three in front and one be- 
hind, at the same level ; hind claw as long or 
longer than the middle claw; greater wing 
coverts not more than half the length of the 
secondaries ; tail of twelve feathers ; posterior 
border of sternum, with a single notch on each 
side ; oil gland naked. 
Picarie. Toes various; the tarsal envelope 
never entire behind ; hind claw not longer than 
middle claw; greater wing coverts more than 
half the length of the secondaries ; tail usually 
of ten feathers; posterior border of the ster- 
num entire, or doubly notched on each side. 
faptores. Bill hooked, with a naked cere; 
toes three in front, and one behind, with 
powerful claws, which are more or less 
retractile ; furculum strong. 
Psittacit. Bill hooked, with a sometimes 
feathered cere; toes two in front and two 
behind; upper mandible articulated to the 
skull; posterior border of sternum entire, or 
simply fenestrated ; furculum weak. 
