DEVELOPMENT OF THE SKULL IN THE BATRACHIA. 
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steep maxillary (figs. 1 and 3, n.,mx.), the bone swells out to finish the front of the orbit; 
these bones are blunt over the wide snout, which lies beyond them; their antero- 
external edge is straight. 
The palatine processes of the premaxillary (fig. 2, px.) grow well inwards near the 
mid-line; on the right side the outer angle forms a separate bone (px'.). 
The nasal processes (fig. 3, px.) are thick “uprights,” propping up the snout, and 
padded with the first labial (u.P.) ; together, these bones occupy a large part of the 
fore face. 
The maxillaries (mx.) are high rough slabs ; their lower margin is gently concave, 
and along it and along the dentary edge of the premaxillaries (fig. 3) there is a row of 
sharp denticles growing from the epidermic sheath ; these atavistic memorials of teeth 
might easily be mistaken for the organs they so closely imitate. The upper margin 
of the maxillary is sinuous ; it rises four times, in front, under the nasal, where the 
pterygoid joins it, and as it binds upon the quadrato-jugal. The palatine margin 
(fig. 2, mx.) is well developed, and of equal breadth up to the fore edge of the cavity 
for the temporal muscle ; the bone then lessens into a sharp curved style, which binds 
the quadrato-jugal up to the hinge—nearly. The latter bone (q.j.) is a flat style, and 
is continuous with the bony half of the quadrate (q.). In front, over the joining of 
the premaxillary and maxillary, there is a semi-circular septo-maxillary (fig. 3, s.mx.) 
obliquely set on to the latter, and raising it nearly to the height of the bone in front 
(' n.px .). Behind this part there is a fenestra between the nasal pouch (fig. 3) and the 
concave edge of the maxillary. 
The squamosal ( sq.) is quite Batrachian, but it is exorbitantly large ; it is a roughly 
cruciform bone, with a sigmoid stem, and a large over-lying temporal plate, which is 
lozenge-shaped (fig. 1). This oblique plate is thick in front, and unites by suture with 
the postorbital projection of the roof bone (fp.) ; the scooped part lies like a scale on 
the parotic region. The postorbital process of this bone looks downwards, it is blunt 
and short; it only reaches half-way to the jugal crest; the pre-opercular portion is 
long, curved backwards, and carinate inside where it binds upon the quadrate. 
The parasphenoid (figs. 2, 3, pa.s.) is only half as long as the basis cranii; and is 
very peculiar. The fore part, for a fourth of its length, is a narrow style ; then the 
bone widens at once, and is notched on both sides. The hind part is triangular, and 
the side bars are oblong and widest behind, and articulate by a toothed suture to the 
pterygoids (peg.). 
The vomers (fig. 2, v.) stand, behind, against the huge palatines; they are sub- 
crescentic shells of moderate size, and are separated by a space more than equal to their 
own width. There is only a _pre-narial snag ; on the left side this is a distinct bone 
like the distinct palatine ossicle detached from the premaxillary on the right side (px'_.). 
In comparing this type of skull with the “ norma,” a good proportion of the dis¬ 
crepances will be seen to be divergences, also, from the typical Bufonine skull, such as 
that of B. vulgaris, or the larger skull of B. pantherinus. 
