122 SPECIMENS OF CETACEA. 



No. 3. Teeth I ^. Mandible, length of, 15^ inches, 



symphysis If inch. 

 Shetland. 



5. Skull, with mandible ; length 19 inches, breadth 12^ 



inches. Length of beak from maxillary notch 10 

 inches ; breadth at base 7| inches ; characters resemble 



No. 3. Teeth ^ ^, Mandible 15 J inches, symphysis 

 o o 



2 1 inches. 



Shetland. 



6. Tympano-periotic bones, pair of, fused (A and B). 



Tympanic length 1| inch, breadth | inch, height f 

 inch ; outer surface with two convexities separated 

 by a shallow depression, the posterior being longer 

 than the anterior ; lip-like process very short on outer 

 surface. Inner surface J inch in height for three- 

 (|uarters of length, then rapidly sloping to Eustachian 

 orifice. Bilobed ; outer lobe smooth, rounded, promi- 

 nent ; inner small, flattened, pointed, cleft deep ; inner 

 lobe continuous with ridge bounding inferior surface 

 internally, whilst externally this surface blends with 

 outer surface ; cavity opens by wide mouth close to 

 anterior end of inferior surface. Periotic length 1| 

 inch, breadth | inch ; meatus large ; tympanic surface 

 of articulation concave, deeply striated. The series 

 of bones, A to L, were from the six Shetland skulls ; 

 ossicles present. Tympanic figured below. 



7. Tympano-periotic bones, pair of, fused (C and D). 



Tympanic length If inch, breadth f inch; periotic 

 length If inch. 



8. Tympano-periotic bones, articulated (E and F). Tympanic 



length 1| inch, breadth | inch; periotic length 1^ 

 inch ; tympanic ossicles present. 



