240 UPPER, OR FLINTY CHALK. 



have borne some resemblance to the Miigil ; but its dentated maxillae, not 

 to mention other obvious differences, distinguish it from the recent in- 

 dividuals of that genus. 



The structure and situation of the anterior dorsal fin, and the re- 

 ticulated scabrous surface of the body, is similar to what is observed in 

 some species o£ JBalistes; but the fossil before us, does not present the 

 slightest analogy in any other respect, to that tribe of fishes. 



The specimen figured by Cuvier, and described by BlainviUe, under 

 thenameof ^mi'a ig?iota*, possesses many characters in common with the 

 fossil before us. It consists of the skeleton of a fish, attached to a block 

 of gypsum. It is twelve inches long, and four inches high ; the head being 

 equal to one-third of the length. It has two dorsal fins occupying the 

 same relative situation with those of the Sussex fossil ; the ventral fins 

 also correspond; the lower jaw is furnished with many small pointed 

 teeth, and the tail is rounded. But the angular form of the head in A. ? 

 Lewesiensis: the spinous rays of the anterior dorsal fin, and the scabrous 

 structure of the scales, separate it most decidedly from the A. ignota of 

 the French naturalists. 



Tab. xxxvii. A portion of the body of Amia? Lewesiensis. 



a. The anterior dorsal fin. 



b. The posterior dorsal fin. 



c. One of the ventral fins. 



The whole surface is covered with scales in an excellent state of pre- 

 servation. 



Tab. xxxviii. A specimen imbedded in chalk, the scales being almost 

 entirely removed. 



a. The lower margin of the orbit. 



b. The maxiUae, with two teeth in the upper jaw. In 



another example the teeth are preserved in both jaws. 



c. The impression of one of the opercula branchialia. 



d. One of the ventral fins. 



e. The air bladder. 



* Nouveau Diet. d'Hist. Nat. Tom. xxviii. Art. Ichthyolites, p. 69. 



