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great dorso-lateral muscles of the trunk. This bone is flat above like a scale, and from its 

 superficial position might be classed with the dermal skeleton : the strong temporal muscle is 

 attached to the two surfaces divided by the ridge on its inferior part : it is moveable up and 

 down upon its anterior ligamentous union. In its relative position and functions it combines 

 the characters of postfrontal and mastoid ; and, since the basilar elements of these cranial 

 vertebrae are confluent, and their spinal elements also form one piece, we may here have an 

 example of a similar confluence of the parapophyses of two distinct vertebrae. 



The midfrontal constitutes the anterior part of the epicranial bone, which is connected 

 with the postfrontals and the cartilage perforated by the olfactory nerves and representing 

 the prefrontals. 



A more remarkable and less easily determinable bone is that triangular horizontal plate, 

 the broad posterior base of which is attached by a ligament to the midfrontal, to the post- 

 frontal, and to the prefrontal processes of the palato-maxillary arch ; whilst the apex forms 

 the anterior extremity of the cranium, and supports at its under part two vertical sharp- 

 pointed teeth. According to the analogy of the cranial structure of the Mureenidee, in which 

 the intermaxillaries are absent, and the nasal bone dentigerous, this bone should be the 

 nasal. It is moveable, up and down, upon its basal joint. 



Each ramus of the lower jaw is composed of an articular and a dentary piece, the latter 

 anchylosed together at the symphysis, and completing the inverted tympano-mandibular arch. 

 The articular piece is a simple slender plate, strengthening the outer part of the articular 

 concavity of the jaw, and closing the outer groove of the dentary, along which it is continued 

 forwards to near the symphysis, where it ends in a point. The articular trochlea is formed 

 by a persistent cartilage, which penetrates the cavity in the dentary, escapes from the fore- 

 part of the groove on the outer surface of the dentary, and joins its fellow, in a small cartila- 

 ginous mass, which fills the hollow in front of the symphysis. The dentary piece sends up 

 a strong coronoid process, and has the notched and trenchant dentinal plate anchylosed to it, 

 corresponding with that of the maxillary arch, and playing upon the posterior surface of the 

 edge of that arch. 



The triangular prefronto-vomerine cartilage closes the anterior and under part of the cranial 

 cavity, and supports the origins of the olfactory nerves, which perforate it in their passage to 

 the cartilaginous nasal capsules. Behind the tympanic pedicle is the preopercular bone, 

 elongated, pointed at both ends, trihedral, with the outer surface concave : its lower two-thirds 

 is attached by ligament to the mandibular or tympanic pedicle. Behind and below this is 

 the interopercular, which is an inequilateral triangular bone closely attached by ligament to 

 the expanded cranial end of the hyoidean arch. 



Only a single ceratohyal is ossified on each side : they complete the arch by a ligamentous 

 junction of their lower extremities, having no intervening basihyal : their upper expanded 

 ends are suspended by a short ligamentous mass to the cartilage immediately behind the 

 tympanic pedicle. 



The capsules of the organs of sense are of nearly equal size ; the eye is the smallest, the 

 nose the largest. The acoustic capsules are principally buried in the lateral cartilages of the 

 skull ; but one of the otolithes protrudes through a moderately wide hole into the cranial 

 cavity. The eye-ball occupies the space between the pre- and post-frontals above, and the 



