OCR Text |
Show 1895.] LORIUS FLAVOPALLIATUS AND PSITTACUS ERITHACUS. 367 The lateral margins of the triangle of the beak, thus viewed, are very slightly convex in both species. But a great difference exists with respect to the nares. These are relatively larger, occupy a much larger portion of the dorsum of the prosopium, and are much more closely approximated than in P. erithacus. The distance from the cranio-facial articulation to a line joining the most preaxial parts of the margins of the nares is quite half the antero-posterior extent of the prosopium thus viewed, instead of less than half ; while the internasal lamella, instead of about equalling the diameter of each nostril from within outwards, is less than a third of it. Fig. 3. Dorsal aspect of skull of Lorius flavopalliatus. I. Lachrymal, constituting the preorbital prominence. po. Postorbital process. A large foramen exists in the middle of the dorsal lamella, separating each of the nares from the cranio-facial articulation, and just behind the outer part of the hinder margin of each nostril. These foramina I do not find in P. erithacus. In the latter species, in the relatively broad lamella separating the two nares, there is a depressed area in the form of two grooves which run backwards-from a point in the middle of a line joining transversely the antero-posterior middle points of the dorsal margin of tbe nares-to the postaxial dorsal margin of the prosopium. From between these two lateral grooves, another groove runs forwards along the middle of the dorsum of the beak, nearly to an imaginary line which would connect the anterior margins of the two depressed areas in front of the two nares or further forwards. The groove then bifurcates, its two branches diverging at an angle of about 12°, and running forwards towards the ventral margin of the beak, but stopping short of it by a distance about equal to the diameter of each nostril, and each ending in a foramen which leads into the substance of the bone, |