PLATE 3 



EXPLANATION OF FIGURES 



5 Ventral surface of the cranium (Pomolobus pseudoharengus). On the 

 right half of the figure the cartilage canal is shown; the ventral segment of the 

 prootic osseous capsule (AOC) has been cut away to expose the septum and 

 opening of the canal for the precoelomic diverticulum. X 5.4. 



6 The cerebral surface of the prootic bone (Pomolobus pseudoharengus). 

 X 6. 



7 The ventral surface of the middle of the skull (Pomolobus pseudoharengus). 

 X 5. 



8 Medial surface of the lateral half of the cranmm, showing the relations of 

 the lateral cartilage plate, the perilabyrinthine canals, the nerves, and the eye- 

 muscle canal (Pomolobus pseudoharengus). X 5. 



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