A NKW GENUS OF KNGYSTOMATID.E — FRY. 



105 



pterygoid. Ventrally it forms the large mass of the suspensorium 

 anterior to the pterygoid. Anteriorly it is fused with the short 

 stout quadratomaxilla. 



The quadratomaxilla or quadratojugal (qm), is short and stout, 

 more so than in Chaperina fusca, and forms an oblique suture 

 with the maxilla anteriorly, and is continuous with the quadrate 

 posteriorly. It is compressed and bears a ventral and dorsal 

 ridge which are continuous with the same ridges of the maxilla. 



The maxilla (nix.) is very compressed and ribbon-like 

 posteriorly, but strengthens towards its junction with the 

 pterygoid. At this junction is given off on the inner side, the 

 palatine lamina (PI. ix., fig. 2, p.L). This plate is well developed 

 and is widest at its union with the same lamina of the pre- 

 maxilla. The maxilla is produced ventrally along its whole 

 length into a sharp, biting edge, while above, towards its anterior 

 end, is developed an incurving crest, which attains its greatest 

 height at a level with the hinder margin of the nasals. From 

 this point it slants forward, decreasing in size, to a blunt tip, 

 which overlies the posterior edge of the premaxilla. 



The premaxillai (PI. ix., fig. 2, pmx.) are moderately developed. 

 The inner edge of the left lies slightly inside that of the right, and 

 the palatine lamina lies under the inner edge. This shingling of 

 the bones is continued 

 still further, for both 

 premaxi 11a laminae 

 underlie the same 

 elements of the 

 maxilla?. Each bears a 

 sharp biting edge vent- 

 rally, which is flush with 

 that of the maxilla. 

 The nasal process is 

 given off dorsally, and 

 runs upwards and 

 bends angularly out- 

 wards, reaching almost 

 to the nostril, 



Fig. 40. A. Columella. B. Auditory opening, 

 tympanic membrane removed. C. Vomer, 

 dorsal and lateral view. 



The vomers (fig. 40 c) are small twisted bones which lie 

 between the anterior process of the ethmoid (a.p.e.) and the 

 terminal portion of the palatine lamina of the maxilla. Owing 

 to the condition of the cartilage of the nasal floor, these bones 

 were removed and cannot be figured in situ. 



