PLATE LIX. 



PAGE. 



Fig. 1. Ctenacanthus FORMOsus, Newb 53 



Xatural size, 

 la, 16, Ic. Transverse sections of spine. 

 Id, le. Surface markings. Eularued. 



Fig. 2. Ctenacanthus FURCiCAKiNATUs, Newb 54 



Base of spine. Natural size. 

 2a, 26. Transverse sections. 

 2c. Surface markings. Enlarged. 



Fig. 3. Ctenacanthus PAKvui.us, Newb 55 



Entire spine. Natural size. 



Fig. 4. Dermal Tubercles OF Ctenacanthus ? 54 



Found with fig. 2. 



Fig. 5. Listracanthus HYSTRix, N. and W 56 



A small specimen. Natural size. 



Fig. (i. Listracanthus HiLDRETHi, Newb 56 



, Summit of spine. Natural size. 



Fig 7. Orthocanthus GRACILIS, Newb..." 56 



A rather large specimen. Natural size. 



Fig. 8. Dinichthys Terrelli, Newb 28 



Supra-occipital plate, inside. Natural size. 



Fig. 5>. Dinichthys Hertzeri, Newb 28 



Supraroccipital plate, inside. Half natural size. 



Fig. 10. Supra-occipital and Dorsal Plates of Heterostius 14 



Inside, much reduced. After Pander. 



Fig. 11. Supra-occipital and Dorsal Plates of Asterolepis 14 



Inside, much reduced. After Pander. 



Fig. 12. Platyodus lineatus, Newb 58 



Crown surface of tooth. Natural size. 



Fig. 13. Ptyctodus calceolus, N. and W 59 



Side view. Natural size. 

 1 3a. Uppei' surface. Natural size. 

 Vib. Pi'ofile section. Natural size. 



