504 MR. W. K. PARKER ON THE OSTEOLOGY OF THE KAGU, 
separated by a notch anteriorly (Pl. XCII. fig. 3). The under surface of the superorbital 
plate of the frontal forms one continuous plate of bone with the alisphenoid, which 
has no fenestra, and which has completely coalesced with all the surrounding bones 
(Pl. XCII. figs. 2 & 3)’. 
The Kagu approaches both the Herons and the Rails in the structure of the inter- 
orbital septum; for the orbito-presphenoid (Pl. XCII. fig. 5) is feeble and oblique; but 
it is feebler and more obiique than in either of those types, the posterior process of the 
perpendicular ethmoid and the alar part of the anterior sphenoid being very feeble at 
their junction. This leads towards Eurypyga, which has complete abortion of the 
connecting bar, as in Himantopus and Phalacrocorax. 'Two small fenestree are seen 
on each side of the feeble four-winged orbito-sphenoid; below, the presphenoid is a 
minute separately ossified spur (fig. 3). As in the Stanley Crane, and unlike that in the 
Night-Heron and Rail, the great ethmo-basisphenoidal bar, bounding the interorbital 
space below, is very deep (fig. 5), and thickens as it approaches the parasphenoidal 
beam. The cleft between the orbital and the nasal septum is incomplete (fig. 5), and 
the latter is partly ossified, as in the Ardeine: it is much deeper than in Gralle 
generally. There are three septal ossifications—two upper (the small one foremost), and 
one lower; this lower bony plate answers to the antero-inferior bone of the Rapacious 
bird—that which sends out the vestibular bars to join the maxillary on each side. The 
nasal septum, like the alz nasi, only occupies the hinder half of the bony nasal opening ; 
the rest is filled up by fibrous tissue. The septum nasi is alate below, and each semilan- 
ceolate cartilaginous wing is attached to the septal process of the maxillo-palatine plate. 
The prefrontal region (Pl. XCII. fig. 3) is only partly ossified, the antorbital plate 
being cartilaginous above and externally, and the perpendicular ethmoid sending very 
little bony matter into the upper ale. ‘The aliseptal region (inferior turbinal and its 
root) and the alinasal are quite soft in the adult; the alinasal flaps are obliquely oblong, 
lie low down, bulge but little, and only reach halfway along the bony nasal opening ; 
the anterior nostril is a low-lying valvular shit. 
As the bony nostrils are extremely open, the body of the premaxillary only reaches 
one-third of the way to the angle of the bone. ‘The nasal processes (Pl. XCII. fig. 1) 
are completely fused, as in the Cranes, the Psophia, the Eurypyga, and the Rail, but 
they keep very distinct from the nasals. The nasal process is strong, flat, even some- 
what concave at the middle of the bone, and is very unlike what is seen in the related 
types. Below (fig. 2) there is seen to be a degree of filling-in by bony matter that 
approaches what we find in the true Herons, and the fusion of the parts is complete. 
‘This narrow, gently concave anterior part of the bony palate is composed of the inner 
part of the dentary plates and the palatine bars of the premaxillaries. Joined to them are 
‘ I must refer the reader to the plates accompanying my paper on the Gallinaceous and Struthious skulls for 
the lettering of especial parts, with this proviso, namely, that p.v. (prevomer) should be read as mx. (maxillary), 
and mx. as pt.mx. (postmaxillary). 
