274: DR. W. G. IMDEWOOD ON THE 



below the pro-otic boues is a rbomboidal patch of teeth, which 

 terminates anteriorly Ib a sharp point, and posteriorly in a blunt 

 point. The teeth increase in size from before backward, and the 

 teeth which occur at the hind end of the series are the largest 

 which the fish possesses. On each side of this patch of teeth 

 the parasphenoid is produced into a stout peg, which slopes 

 slightly forward and downward, and articulates with the ento- 

 pterygoid in the same manner as in the Osteoglossidse. There 

 are no wings of the parasphenoid ascending towards the post- 

 frontal and alisphenoid; the eye-muscle canal does not open 

 posteriorly. 



On each side of the hinder part of the base of the cranium is 

 an inflated bulla of very thin bone, through which may be seen a 

 large otolith. The bulla is formed by the pro-otic, basioccipital, 

 and exoccipital bones. A subtemporal depression, having more 

 the form of a groove running antero-posteriorly than of a fossa,, 

 is situated above the level of this bulla, and below the posterior 

 part of the articular facet for the reception of the head of the 

 hyomandibular. There is no auditory fenestra, and there are no 

 diverticula of the swim-bladder contained within the skull. A 

 half-centrum is fused with the exoccipital and basioccipital 

 bones, and the suture between it and the exoccipitals remains 

 visible. The anterior vertebrae are normal, and there are no 

 Weberian ossicles. The posterior temporal depressiou is not 

 roofed over. A separate opisthotic seems to be wanting. Owing 

 to the great breadth of the orbital region of the cranium, the 

 two alisphenoids are set at a considerable distance apart, and the 

 orbitosphenoid has the form of a widely open U, the right and 

 left parts of which are nearly severed. There is no basisphenoid- 



The preopercular is a bone of normal size ; it has a short 

 horizontal limb, the extremity of which nearly touches the back 

 of the mandible. There is no interopercular. The circumorbital 

 bones are missing from the skull under consideration ; but it 

 may be noted that Peters has figured two large postorbital plates^ 

 Avhich extend nearly to the edge of the preopercular, and 

 Boulenger writes (Z. c. p. 120) : " La joue est cuirassee par deux 

 grands sous-orbitaires." 



The maxilla is long ; its anterior extremity projects in advance 

 of the premaxilla, its posterior end is close behind the level of 

 the quadrate-mandibular articulation. The lower edge of the 

 maxilla is toothed from end to end, the teeth being arranged in 



