502 MR. W. K. PARKER ON THE OSTEOLOGY OF THE KAGU. 
called “ turbinal” 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. y. p. 157), should reappear in the Bird as enormously developed as the premaxillary, 
and that thus I had an explanation of those quasi-turbinal 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 occurred 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, mnus 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 /ess 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 Psophia and the Sun-Bittern, and calling this 
group the “ Psophiine,” 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 ‘‘ Grall,” the Night-Heron’s skull and 
