Newberry — On a new Devonian Fish, 



185 



marked peculiarity in the anatomical structure relates to the form 

 and texture of the jaws and teeth, best understood by the annexed 

 figures. 



Fip. 1. Anterior aspect of head of Dinichthys Herzeri, one-eighth nat. size. 



Fig. 2. Mandible of Dinichthys Herzeri, one-eighth nat. size. 



The head terminated anteriorly and above in two great incisors, 

 representing the premaxillarj'-, behind which on either side are 

 the maxillaries, broad, flattened, dense bones, along the lower 

 edge of which is set one row of small robust teeth, formed by the 

 consolidation and prolongation of the jaw-tissue. The mandibles are 

 over two feet long by six inches deep, laterally flattened and very 

 massive. The anterior extremity was turned up in a huge triangular 

 tooth composed of dense ivory-like tissue, which locked in with 

 the divergent incisors of the upper jaw. Behind this, in some 

 specimens, is another triangular summit, and posterior to it a 

 row of small teeth, corresponding with those of the maxillaries. 

 Such was the power of this tremendous dental apparatus, that the 

 bodies of our largest living fishes would be instantly pierced and 

 crushed by it, if exposed to its action. Behind the head are large 

 thick plates, one of them corresponding to the os medium dorsi of 

 the Heterosteus of Pander, and being at least of equal size. These 

 bones occur exclusively in concretions. 



VOL. V. — NO. XLIVJ. 



13 



