PSEUDORCA CRASS I DENS. 
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great broad-nosed dolphins having only a feeble, or defective set of teeth, whereas the form of 
the lower jaw of our cramdens and the killers is called forth and necessitated by powerful 
and large teeth. It is further a consequence of the size of the teeth, that the dental row, just as 
in the killers, occupies the larger half of the whole length of the jaw, although the teeth are 
hardly so numerous as in the ca’ing-whale, in which the dental row (even before a single tooth 
has as yet fallen out) does not occupy more than a third of the jaw; and finally, and partly for 
the same reason, the difference between the greatest height of the jaw behind and its smallest 
height close to the symphysis, is not so considerable as in the ca’ing-whale, and the symphysis 
itself is comparatively longer than in the latter species ; but in these two respects also 
our dolphin bears a close resemblance to the killer. The considerable size of the teeth (com¬ 
paratively speaking, scarcely smaller than those of the killers) has already been briefly alluded 
to, we must now give a more minute description of them. They are slightly curved in an 
inward direction, and placed in deep sockets, which both in the upper and in the lower jaw are 
completely separated from each other through their whole extent, whereas the sockets of the 
teeth of the killers are most frequently only imperfectly separated. Only between the two 
hindmost sockets the partition may sometimes disappear, and the cavities may thus become 
more or less completely coalesced. In the lower jaw, the foremost socket approaches the point of 
the jaw as much as possible; but such is not the case in the upper jaw, as the intermaxillaries 
project in front of it, though only very slightly. The roots of the teeth seem to close 
much faster than in the majority of the killers; at least the roots are still perfectly open in 
the teeth of several crania of a species of large killer from the seas round the Faroe Islands, 
which belonged to animals middle-aged, at least, rather than to young ones; whereas the 
teeth even of the Refsnaes individual of the species here described have their roots perfectly 
pointed, and it is only in the largest teeth that an insignificant aperture is left in the points of 
the roots leading into rather a narrow internal cavity. In the upper jaw, the teeth increase in 
size progressively backwards up to the last tooth, w r hich becomes suddenly again con¬ 
siderably smaller than the preceding one; in the lower jaw, the foremost tooth is also very small, 
scarcely half as large as the second one; then the teeth uniformly increase in size up to the 
seventh or eighth, which are of about the same size; the ninth is again a little smaller, and the 
hindmost again less than half the size of this one. The teeth are almost of the same size in 
both jaws ; the largest are two and a half inches in circumference just above the alveoli, and 
have a length of about three inches, of which the enamelled crown occupies about one third. 
The number of the teeth is subject to individual differences; Mobius 1 states that the number of 
the teeth of the individual caught in the harbour of Kiel, is twenty in either jaw, ten on 
either side, and Professor Behn has confirmed this statement in a letter to the author of this 
memoir. But this number we do not find repeated in any of the individuals stranded on the 
Danish coasts, nor do the latter quite agree with one another as to the number of their teeth. 
Thus, the individual stranded at Middelfart has nine teeth on either side of either jaw, the 
total number being smaller by four than in the Kiel dolphin, and there is not the slightest trace 
of its having had more teeth at an earlier period of its life. In the Asnses specimen, the teeth 
had fallen out, and only one or two were found lying on the beach, where the body was landed ; 
but by the quite uninjured sockets we may ascertain w r ith perfect certainty, that this individual. 
1 1. c. page 3. 
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