32 



pharyngeal plate, and of the two superior pharyngeal plates is well shown in 

 this specimen. The inferior plate is supported by the two confluent basi- 

 branchial bones of the last branchial arch : the superior plates are supported 

 by the pharyngobranchial pieces of the three posterior branchial arches. 



Hunterian. 



116. The skull of a large Parrot-fish (Scarus), with the integuments remaining on 



the right side. The numbers indicate the names of the bones according to 

 Table I. 



The suspension of the maxillary arch through the medium of the palatine from the pre- 

 frontal is well shown, and the correspondence of the articulation between the maxillary and 

 the premaxillary with that between the articular and dentary pieces of the lower jaw, is very 

 close and illustrative of their serial homology. The pretympanic and hypotympanic bones 

 are of great breadth. The borders of the premaxillary and dentary pieces are paved with 

 hard enameled denticles, so placed that they oppose each other by their sides instead of by 

 their summits. 



This specimen was formerly preserved in the museum of the Royal Society ; 

 and is figured in " WilluglMi de Historia Piscium, Joannes Raius, 1686, tab. 

 X. ii : Ingentis cujusdam piscis Indici caput, an e'Turdorum genere ? e M. 

 S. R." Mm. Brit. 



117. The right halves of the maxillary and mandibular arches, with a portion of the 

 tympanic pedicle of the same side of a large species of Scarus. The consti- 

 tuent bones are indicated by the numbers affixed to them according to 

 Table I. Hunterian. 



118. The bones of the head of a small species of Scarus. 



The anterior expansion of the vomer, and the lateral processes of the basioccipital and basi- 

 sphenoid, which form the articular cavities for the superior pharyngeals, are worthy of notice 

 in this specimen ; as also the depression above the nasal and fore-part of the frontal bones, 

 upon which the long nasal processes of the premaxillary bones play backwards and forwards 

 in the protractile and retractile movements of the jaws. 



Hunterian. 



119. The premaxillary, premandibular, and pharyngeal bones and teeth of a small 



Parrot-fish, of that section of the genus in which there are no lateral out- 

 standing pointed premaxillary teeth. Hunterian. 



