ON’ THE MORPHOEROGY OF CERTAIN. \OF* THE 
BONES OF £BE CHEEK AND TSNOUT OF 
AUNETAS ‘CALLA: 
EDWARD PHELPS ALLIS, Jr. 
Tue bones it is my purpose here to consider are, in Sage- 
mehl’s nomenclature (Nos. 35, 36), the preoperculum, the post- 
frontal, the infraorbital and antorbital chains of bones, the 
prefrontal, the nasal, the vomer, and the maxillary bones. The 
infraorbital bones are the two postorbitals, the two suborbitals, 
and the lachrymal. The antorbital bones are the antorbital and 
the median ethmoid. The maxillary bones are the maxillary, 
the premaxillary, the septomaxillary, and the supramaxillary. 
The supramaxillary of this nomenclature is the jugal of both 
Bridge’s descriptions and my own (Nos. 7, 3). The prefrontal 
is the lateral ethmoid or ectethmoid of most English writers, 
and is the preorbital ossification of all my figures, though often, 
in my descriptions, called by me, as by Sagemehl, the prefrontal. 
Of these several bones, the preorbital ossification and septo- 
maxillary are cartilage bones, or so-called primary ossifications ; 
that is, they are developed in direct relation to, and replace 
parts of the chondrocranium. Whether they are, in Amia, of 
endochondral or perichondral origin I have not yet attempted 
to investigate. 
The remaining bones are all dermal bones, or so-called sec- 
ondary ossifications, but they belong, by origin, to two some- 
what different categories. 
The maxillary, premaxillary, and vomer all bear teeth, and 
hence belong, beyond question, to those bones that are devel- 
oped in direct or indirect connection with the teeth of the 
animal. The supramaxillary bears no teeth, but its homologue 
in teleosts is considered by Sagemehl as phylogenetically 
derived from teeth-bearing plates similar to and continuous 
with those that, according to him, fuse to form the maxillary 
(No: 36; p: TOR). 
