Page. 



8 connecticut geol. and nat. hist. survey. 



Figures in Text. 



i. Cephalaspis murchisoni Egerton. Lower Old Red Sand- 

 stone ; Herefordshire. ( After A. S. Woodward) . 14 



2. Outlines of Acanthodian Fishes. A, Climatius scutiger 



Egerton. B, Mesacanthus mitchelli (Egerton). C, 

 Acanthodes sulcatus Agassiz. D, Acanthodes gracilis 

 Roemer . . . . . . .15 



3. Cladoselache fyleri Newberry. Cleveland shales (Upper 



Devonian); near Cleveland, Ohio. (After Bashford 

 Dean) ....... 16 



4. Dipterus vale?iciennesi Sedgwick and Murchison. Lower 



Old Red Sandstone ; Scotland. (After R. H. Traquair) 17 



5. Catopterus redfieldi Egerton. Trias ; Durham, Connecticut. 



Reproduction of Newberry's original drawing of dorso- 

 lateral aspect of the head ..... 54 



6. Catopterus redfieldi Egerton. Trias; Durham, Connecticut. 



Reproduction of Newberry's original drawing show- 

 ing under side of the head . . . .54 



7. Comparative diagrams showing types of cranial structure. 



1, Rhabdokpis. 2, Nematoptychius. 3, Rhadinichthys. 



4, Palceoniscus. 5, Se??iionotus . . . -59 



8. Semionotus agassizii (W. C. Redfield). Trias; Sunderland, 



Massachusetts. X£ . . . . .62 



