510 MR. W. K. PARKER ON THE OSTEOLOGY OF THE KAGU. 
rowest part, and is much dilated at its base, which turns inwards and forwards. There 
are a deep “ quadrato-jugal cup,” a high and neatly finished semioval convex “ pterygoid 
condyle,” and two reniform convexo-concave condyles for the “articulare ;” the inner of 
these is the lesser, and has the “hilum” looking backwards; the outer has its concave 
margin looking forwards and inwards. 
The mandibles are typically Gruine, but there is a good Ardeine character even in 
them ; this is the long retral process between the mandibles (Pl. XCII. fig. 1a), growing 
backwards from the ankylosed symphysis'. Here, again, the Kagu and the Eurypyga 
correspond, whilst in the Psophia there is the merest rudiment of this part. The fore 
part of the dentaries is like the fore part of the intermaxillaries; further backwards 
(Pl. XCII. fig. 3a) the ramus is high, as in Anthropoides, and only lowers a little in 
front of the hinge, where it becomes thick also. The fore part of the “coronoid” and 
the hinder part of the ‘“splenial” is unankylosed; the “dentary,” also, has not coa- 
lesced with the combined “ angular” and “ surangular.” The fenestra which appears in 
the Psophia, between the forks of the dentary behind, is filled up; so is that which is 
seen in the Stanley Crane and the Eurypyga above the root of the “coronoid” and 
through the substance of the “surangular;” in this the Kagu agrees with the Grey 
Heron: there is a trace of this fenestra in Nycticorax. The convexo-concave condyles 
(Pl. XCII. fig. 1 @) conform exactly to those of the os quadratum, the concavities and 
convexities being reversed. The posterior face of the mandible is essentially Gruine, but 
most evidently Ardeine also; it is triangular, the upper and outer edge forming a right 
angle (Pl. XCII. fig. 42). 
The “internal angular process” is blunt, and perforated for the passage of air; the 
‘“ outer angular process” is rather sharp, and projects downwards as much as backwards. 
In the posterior face of the mandible the Kagu agrees with the typical Gruine, but 
makes some approach to the Ardeine; in the Ewrypyga the Ardeine characters prepon- 
derate, whilst the same part in the Psophia is about equal to that of the Kagu. 
The ceratohyals are lost in my specimen; I suppose that they were long, slender, 
and unossified. The basihyal (figs. 8 & 8q@) is rather long, slender, and well ossified ; 
the urohyal is small, slender, and scarcely ossified at all; and the thyrohyals are slender 
and feebly ossified. 
The sclerotal ring is ossified; but the bony plates are scarcely larger than in Psophia, 
with a much smaller eyeball. In Dicholophus, which has the eyeball but little larger 
than that of the Kagu, the sclerotals are twice as large and twice as strong, and the 
diameter of the ring is but little short of an inch (113 lines) from edge to edge. In the 
Kagu this diameter is 2 lines less; and in it the sclerotals turn forwards very little at 
their inner edge; in Dicholophus this Owl-character is very strongly developed. 
The vertebre vary as to number in the Kagu and its relatives, as follows :— 
‘ Tn this character the Herons and Pelecanine birds agree; in the Cormorant and Gannet this process is 
well developed. 
