Dinichthys pustulosus Eastm. 



(.See plates 2 and 5) 

 Page 130 



Dorsal aspect of moderate sized head shield, showing cranial sutures, 

 sensory canals and other features very distinctly. The median 

 occipital plate is removable, showing conformation of visceral surface. 

 X ^ 



Lower part of the Cedar Valley limestone (Middle Devonic) ; near 



Rock Island, 111. Collected by A. S. Tiffany 



Original in Museum of Comparative Zoology, Cambridge, Mass, 



ii8 



