Page:The Geologist, volume 5.djvu/130

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106
THE GEOLOGIST.

"The Squalodon and the Zeuglodon evidently resemble each other in the singular conformation of their dental system. But what is the degree of their affinity? To what family do they belong? Or do they form a type completely lost? and, in the case of an affirmative, what place ought to be assigned to them?

"These questions, and many others, wait for solution; and it will be readily conceived what high value is attached to the discovery of some bones of the Squalodon in the Crag of Antwerp.

"We are fortunately now in possession of many important portions of the head, the extremity of the upper maxillary, the intermaxillary with its teeth, the posterior part of the palate, many fragments of the inferior maxillary, and other parts of the skeleton.

"Lastly, to make out every possible part of these precious relics, the Government has, at the request of the Academy, commissioned me to visit the principal Museums of Germany and Austria; and we hope shortly to produce a work containing a reply to these different questions. The museum which most interested us in our last journey is the Vaterländisches Museum of Lintz, which contains the most precious remains of the Squalodon that are known. They were deposited there by M. Ehrlich. Thanks to the intelligent and active care of that able naturalist, this Museum contains, moreover, other fossils of high interest from the basin of Lintz.

"We have found there two much-broken portions of the cranium of the Squalodon: knowing before the base of the palate, and possessing fragments of the jaws with the teeth, and moreover the upper maxillary, it was not difficult for us to reconstruct the head of this aquatic carnivore. The dental system of these animals is equally well known to us now, even to the principal differences the species present between each other,—at most only a doubt remains on the subject of one of the molars.

"We will say a word on its characters.

"The cranium is greatly depressed; the parietals form a part of the cephalic box, and the frontal bones extend regularly forward and over the side, without being folded back (refoulés) by the nasal cavities, as in the true cetacea. The zyomatic arches are large, but incomplete. The teeth are of three kinds, but put on only two different forms; the incisors and the premolars are like the canines; six incisors are implanted in the bone of that name, and of these six incisors the two middle ones are directed forwards in the direction of the axis of the body, not like the sword of the narwhal, but more like the great incisors of the shrew-mouse. The canines are succeeded by five simple premolars, regularly spaced; then seven true molars with two fangs and a compressed and crenulated crown (chiefly on the hinder edge) complete this singular dental system.

"We have been able to convince ourselves, also, from the tolerably perfect head of the Squalodon at Lintz, that, contrary to our anticipations, the nasal holes are directed from back to front, and differed in this respect from the existing blowing-whales. In the latter we know the cavity of the nostrils rises straight up, or even slightly backwards, and that it is this direction which permits their spouting perpendicularly their columns of water, or rather of vapour, from their nostrils. If we wished to figure the Squalodon as the dolphins are commonly represented, it should be drawn ejecting columns of vapour obliquely forwards, and not upwards. We endeavoured to profit, also, by our sojourn in Germany, in learning what were the other inhabitants of the sea which nurtured the Squalodon, in order to compare it with our Crag Sea. There is in the same Museum at Lintz a cranium of the highest interest in this comparative study. All the posterior portion is tolerably complete. It approaches closely by its size