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Show 1899.] CRANIAL OSTEOLOGY OF THE PARROTS. 39 scarce a perceptible interruption on to the upper border of the squamosal. In Nymphicus, the inner head of the quadrate is ill-defined ; in Platycercus it is separate but very small: in both the shaft is slender, the anterior process very small, and the pterygoid condyle scarcely separate from the mandibular. Fig. 40. Melopsittacus undulatus. In Melopsittacus we have a complete orbit, and furthermore a bridge of bone crosses the temporal fossa, uniting the postfrontal process to the squamosal, precisely as in the Cockatoos, though leaving a proportionately small fenestra. The characters of the base of the squamosal region, of the base of the skull, of the intraorbital vacuity, and of the mandible resemble those of the other Platycer-cmce. The quadrate is very like that of Nymphicus. In the hyoid of Melopsittacus, by the way, the parahyal processes form an arch, meeting together above the basihyal, precisely as Dr. Mivart has shown in the case of the Lories. RECAPITULATION. From the foregoing facts it seems to me easy to draw certain interesting conclusions, though many questions are still left imperfectly answered. In the first place, the isolation of Nestor is very evident. The whole character of the squamosal and auditory region of the skull is unique, and unapproached in any other Parrot. The great size of the intraorbital vacuity and of the mandibular fenestra, the shape of the quadrate, as well as the more obvious peculiarities in the shape of the beak and mandible, all distinguish the skull at a glance. There is no osteological ground for allying Nestor with the Lories as in Dr. Gadow's scheme, any more than with Psittacus and Ara as in Garrod's. Its right to constitute a separate family as instituted by Salvadori seems perfectly clear, and indeed Prof. Newton (Diet, of Birds, p. 629) has already remarked that Salvadori's view "is fully justified by a cursory examination of its osteology." Though less striking at a glance, the cranial peculiarities of Stringops are certainly no less important. I am inclined to attach high importance to the characters of the quadrate bone, in which, as I have shown above, the short thick shaft, the large broad anterior process, the great ridge bearing the jugal cup, and the position of the pterygoid condyle, widely separate from the mandibular articular surface, are all unique among the Parrots, in all the |
