DEVONIAN ANIMALS. 



337 



Dinichthys (Fig. 423) and Titanichthys were similarly plated on head 

 and body. Others, however, such as the Osteolepis (Fig. 432), the 



Fig. 432.— Osteolepis (after Nicholson). 



Holoptychius (Fig. 431), Diplachanthus (Fig. 434), etc., had more fish- 

 like forms, and were covered with movable ganoid scales, either rhom- 

 boidal or imbricated. 



Fig. 436. 



Figs. 433-436.— Devonian Fishes— Lepidoganoids : 433. Glyptolemus Kinairdii (after Nicholson). 

 434. Diplacanthus gracilis (after Nicholson). Placoids : 435. Ctenacanthus vetustus, Spine re- 

 duced (after Newberry). 436. Machaeracanthus major, Spine reduced (after Newberry). 



Perhaps the most extraordinary and certainly the largest of all 

 Devonian fishes belong to the family of Dinichthys. The peculiar 

 structure of jaws and teeth is shown in Fig. 423, taken from Newberry. 

 Almost equally remarkable is another Ohio fish described by Dr. New- 

 berry, the singular teeth of which are shown in Figs. 425 and 426. 

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