36 ILLINOIS BIOLOGICAL MONOGRAPHS [206 



EXPLANATION OF PLATE 



I 

 Fig. 3. Prepoercul^r of Scorpianichthys marmoratus. Two-thirds natural size. 

 Fig. 4. Preopercular of Ophidon elongatus. Two-thirdds natural size. 

 Fig. 5. Lateral view of skull of Scorpianichthys marmoratus. Two-thirds natural 



size. 

 Fig. 6. Lattral view of skull of Ophidon elongatus. Two-thirds natural size. 



