True. — The fossil cetacean, Dorudon serratus. 



PLATE 3. 



Dorudon serratus Gibbes. 



Fig. 1. Left half of mandible (broken at both ends). Lateral aspect. (Gibbes, 



1847, Plate 3, figure 1.) 

 Fig. 2. Portion of right ramus of mandible. 

 Figs. 3-5. Eibs. 



