502 ME. W. K. PAEKEE ON THE OSTEOLOGY OF THE KAGU. 



called " tuibinal " was, in reality, one of the maxillary series, it seemed to me perfectly 

 possible that this bone, which I proposed to call the " prevomer " (see Zool. Trans. 

 vol. V. p. 157), should reappear in the Bird as enormously developed as the premaxillary, 

 and that thus I had an explanation of those quasi-turhiiial outgrowths which make the 

 maxillary of the Bird so unlike that of a Mammal. 



Thus it appeared that the true maxillary was only exceptionally present in the Bird, 

 and that the huge prevomerine splint not only retained its reptilian character but also 

 grew largely into tracts which were left open to it by the abortion of the " maxilla 

 proper." 



Nothing occiu-red to disturb this view until the end of the year 1865, when Professor 

 Huxley very forcibly put it to me that the bird's great maxilla does actually correspond 

 to that of the mammal, minus its outer alveolar plate ; this view is given in my paper 

 on the Ostrich's skull (Phil. Trans. 1866, pp. 113, 114). If that view were the true 

 one, then the so-called "turbinal" of the Snake and the Lizard might also be referred 

 to the same category. Frequently returning to this subject, being severely criticised 

 by Professor Huxley for using the term " prevomer," and receiving new ideas upon the 

 subject from fresh research, I have at last determined to alter my nomenclature. I 

 give up the obnoxious term " prevomer," and propose to call the pseudo-turbinal splint 

 the " septo-maxillary"; the small additional maxillary of certain birds may be called the 

 '• postmaxillary "; and the great upper jaw-bone of the bird will retain its old name — 

 the " maxillary." Nevertheless it is less than the maxillary of the Mammal, its outer 

 alveolar plate being aborted by the premaxillary ; and more, for it oftentimes has the 

 attributes of the "septo-maxillary" added to its own, although in the Bird merely as a 

 region, not as a distinct osseous piece. I have traced, as I think, the septo-maxillary 

 through a large series of Ovipara, from the Ganoid fish to the Lizard ; I am quite pre- 

 pared to see it continuous with the maxillary of the bird, which has many splint-bones 

 single that are double in the Lizard. A few other changes will be spoken of in the 

 course of my description ; but the maxillary series has presented the greatest difficulty, 

 and needed to be put plain at once ; for my determination of the so-called " turbinals " 

 of the Lizard to belong to the maxillary splint-system, and the discovery of the attri- 

 butes of these bones in the maxillaries of the bird, have caused no little difficulty in the 

 nomenclature of those parts. 



I have already ventured to classify the Kagu (see ' Shoulder-girdle and Sternum,' 

 p. 158), putting it into a family with the Psojtliia and the Sun-Bittern, and calling this 

 group the " Psophiina?," with the qualification, however, that each of the three types 

 deserves to be placed at the head of a distinct subfamily. These Psophiine types are 

 essentially Cranes, but they are very aberrant. 



Notwithstanding the essential relationship of these three " Geranomorphs," the first 

 view of their skulls would not suggest so near an affinity. If the Kagu's skull be 

 placed in the midst of a series of skulls of the " Gralla?," the Night-Heron's skull and 



