no 



ILLINOIS BIOLOGICAL MONOGRAPHS 



[110 



EXPLANATION OF PLATE 



Fig. 3. — Model of chondrocranium of 32 mm. Amiurus, dorsal view. On the right side only 

 cartilage parts are shown, on the left the bones as well, cartilage being stippled to con- 

 trast with the bones. 



Fig. 4. — Same, ventral view, cartilage only on left side, cartilage and bone on right of drawing. 



