EXPLANATION OF PLATE IV. 



Halicore dugong, Gmelin, sp. 



Fig. 1. Portion of a rib showing cuts and chipping of the surface. 



, 2. Largest rib-portion with traces of numerous cuts contiguous 

 to the concave edge 



„ 3. Third rib-portion similar to fig. 1. 



(The figures are seven-tenths the natural size). 



