EXPLANATION OF PLATE XL. 



Portheiis molossus, one-half natural size, from the type-specimen (See Plate xxxis). 

 Fiii. 1. Mandibular ramus, from the iuner side. 



2. Palatine bone, with malleolar body, from above ; 2 a, from the outer side. 



3. Sclerotic ossifications from the outer side ; 3 a, from iuner side. 



4. ? Hyomandibular from the outer side ; 4 a, from the inner side. 



5. Quadrate bone, including the symplectic. 



6. Preiiperculum. 



7. ? luteroperculum. 

 Figs. 8-9. Uncertain bone 



