GREGORY: FISH SKULLS 



113 



iab 



( scaledone) 



po. ros 



po.ro:. 



civ 



^P'!^ • 



Palaeoniscusmacropomus.' 



p^P f)a. \ / 



pores- 



Cheirolepis trailli 



Fig. 12. Skull patterns of palsconiscids. 



A. Cheirolepis trailli, Devonian age. After Watson. 



B. Palaoniscus macropomus, Carboniferous age. After Traquair. 



C. Coccocephalus wildi, Carboniferous age. After Watson. 



In Cheirolepis the plate K seems to correspond with the part of the "spiracular ossicles" of PolypUrus. For the top view of 

 this skull see Fig. 8 A, p. 106. The primitive paired rostrals and median postrostrals are well developed. 



