1895.] LORIUS FLAVOPALLIATUS AND PSITTACtTS ERITHACITS. 377 



The dorsal aspect of the cranium (see fig. 3, p. 367) shows, in 

 both species, a surface which is convex both antero-posteriorly and 

 transversely. It is, however, much flattened between the orbits. 

 In L. flavopalliatus there is a slight though marked depression 

 in the hinder part of the interorbital region, which is hardly to te 

 detected in P. erithacus, while in the latter species there may be 

 a median longitudinal depression in the parietal region which does 

 not exist in L. flavopalliatus. In both the dorsal surface of the 

 cranium may be said to be bounded by ten margins. 



The first or preaxial margin is that which adjoins the pro- 

 sopium, and is on the whole very slightly concave. 



The second and third margins (the two preorbital margins) each 

 proceed outwards and postaxiad from one, outer end of the first 

 (prosopiad) margin to the preorbital prominence of the same side, 

 and each is about half as long as is the lateral margins of the pro- 

 sopium. The two preorbital mai'gins diverge postaxiad at an angle 

 of about 95° in L. flavopalliatus and of about 80° in P. erithacus. 



The fourth and fifth margins form the anterior part of each 

 orbital margin (each anterior orbital margin), while the sixth and 

 seventh margins of the dorsum of the cranium constitute the 

 posterior part of each orbital margin (each posterior orbital margin). 

 The anterior and posterior orbital margins meet at a marked angle of 

 about 120°, the apex of which is a little in front of the middle of 

 each orbit's margin. In P. erithacus they run into each other in a 

 curve with only a faint indication of an angle of about 140°, and 

 this is at approximately the middle of each total orbital margin. 



An axial groove, rather wide and shallow, runs along each side 

 of the dorsum of the cranium within the orbital margin, the two 

 grooves being separated by the moderate transverse convexity of 

 the interorbital region. There is a sei-ies of foramina in each 

 groove, which is more marked in P. erithacus than in L. flavo- 

 palliatus. 



The eighth and ninth margins of the cranial dorsum (the two 

 temporal margins) extend from the postorbital prominence to the 

 outer end of the lambdoidal ridge of either side. Each pi'esents a 

 sigmoid curvature, concave behind the postorbital prominence and 

 then convex in the squamosal region, external to which the supra- 

 meatal process, the posterior end of the zygomatic process of the 

 quadrate, and the hinder end of the zygoma may appear. 



The tenth, or occipital, margin presents in both species a gentle 

 convex curvature with a small median concavity. 



The ventral aspect of the cranium exhibits, in both species, a 

 roughly quadrilateral outline, the smallest margin of which is pre- 

 axial and corresponds with the postaxial margin of the prosopium. 

 The lateral sides are the longest and coincide with the zygomata 

 (z) and quadrates (q), while the hinder margin is convex and 

 formed by the occiput. The palatines (p) extend forwards much 

 beyond its anterior m.argin, and each preorbital prominence projects 

 outwards beyond the preaxial third of the zygoma. 



In the middle of the anterior part of the hasis cranii is a rather 

 elongate space, bounded in front by the postaxial margin of the 



