THE DEVONIAN FISHES OF MISSOURI 63 



Isolated bones from the Upper Devonian at Louisiana, not 

 identified with any species. Collection of Mr. Rowley. 



External Occipital of Dinichthys: (Plate III, fig. 5.) 

 This bone differs from that of D. rowleyi in being smaller, having 

 a less prominent prong, a shallower socket, and in widening 

 toward the front instead of being widest at the back. 



Occipital of Dinichthys: (Plate I, fig. 3.) This bone 

 is slightly larger than the occipital of D. rowleyi, the upper 

 surface is smooth, and the lower surface is marked by a deep 

 depression in the middle near the back end. It is wider than 

 D. rowleyi in proportion to its length. 



Fin Rays of Dinichthys: (Plate III, figs. 2 and 6.) The 

 ray shown in figure two is oval in cross section, 15 mm. in longer 

 diameter and 12 mm. in shorter diameter at the larger end. 

 The ray shown in figure 6 is preserved almost entire. 



Postero-Dorso-Lateral of Dinichthys: This bone is 15 

 cm. long along the outer edge and its greatest width is 8 cm. 

 It seems to present no peculiarities worthy of note and the 

 writer was not able to place it with any species. 



Several fragments probably belong to Titanichthys though 

 they are massive for that genus. The most complete bone is 

 shown in plate I II, figure 7. The figure is about two-thirds 

 natural size. 



CHIMAEROIDEI 



Ptyctodus ferox Eastman 

 (Plate IV, figs. 3 and 4) 



1898. Ptyctodus ferox Eastman, Amer. Nat., 32, p. 480, text- 

 figs. 35-40. 



1899. Ptyctodus ferox Eastman, Jour. Geol., 7, p. 282. 



1906. Ptyctodus sp. Dean, Carnegie Inst. Wash., Pub. no. 32, 

 p. 139, text-fig. 126. 



1907. Ptyctodus ferox Eastman, Mem. N. Y. State Mus.,10, 

 p. 72. 



1908. Ptyctodus ferox Eastman, la. Geol. Surv., 18, pp. 135- 

 137, text-figs. 20-22. 



