198 
RIENHARDT ON 
In the facial part (“ the beak”), the resemblance to the killers is, perhaps, somewhat less 
striking ; for this part is shorter than the remaining part the skull, contrary to what is the case in 
Fig. 2. 
those crania of killers which 1 have examined; it is moreover very broad, and obtusely rounded in 
front, and is also distinguished by tapering very slightly and very uniformly in a forward direction, 
so that it is not much narrower even in the middle than in the place where it is broadest farther 
behind, and these characters seem to become continually more distinct as the animal advances 
in age; at least we have found that the cranium of the Asnses dolphin, evidently an extremely old 
individual, was the one of the three having the shortest and broadest beak. One thing, how¬ 
ever, produces a most conspicuous difference between our dolphin and the Orcas, we mean the 
different breadth of the intermaxillaries ; for when we add the fissure between them filled with 
the cartilage of the primordial vomer, then these bones occupy about two thirds of the whole 
breadth of the beak in our crassidens, while in the Orcas they are much narrower than the 
superior maxillaries. In this respect we find unquestionably a likeness with the ca’ing-whales, in 
which the intermaxillaries, as is w r ell known, are also, and even in a still higher degree, remarkable 
for their breadth ; but beyond this no further resemblance is to be found with these in the struc¬ 
ture of the beak. In the ca’ing-whales, far more than in our dolphins, the unusual size 
of the intermaxillaries is produced at the expense of the superior maxillaries, and it is not 
strange that the latter have a diminished share in the breadth of the beak, as the feeble set of 
teeth of these animals only requires small and shallow sockets. Behind the short row r of 
teeth, the alveolar margin is further gradually twisted in such a way as to have an edge turned 
outwards, and this exterior margin of the superior maxillaries is not placed on a level with the 
intermaxillaries behind, but a little above them, by which means the surface of the beak be¬ 
comes somewhat concave in this place. It is true that the intermaxillaries of Cuvier’s Delp/unm 
