DESCRIPTION OF TWO SQUALODONTS RECENTLY DIS- 
COVERED IN THE CALVERT CLIFFS, MARYLAND; 
AND NOTES ON THE SHARK-TOOTHED CETACEANS. 
By Remineron KeE.Lioae, 
Of the Bureau of Biological Survey, United States Department of Agriculture. 
INTRODUCTION. 
When the study of paleontology was less advanced than it is at 
present, any announcement of the discovery of prehistoric animals 
unlike the living indigenous fauna was usually received with some 
suspicion. In spite of this distrust, many attempts were made by the 
early writers to explain the presence of fossil remains of marine 
mammals in strata above the sea level or at some distance from the 
seashore. In one of these treatises‘ is found what is, apparently, 
the first notice of the occurrence of fossil remains referable to shark- 
toothed cetaceans. The author of this work figures a fragment of a 
mandible, obtained from the tufa of Malta, which possesses three 
serrate double-rooted molar teeth. 
Squalodonts as such were first brought to the attention of paleon- 
tologists in 1840, by J. P.S. Grateloup, ?a French naturalist primarily 
interested in marine invertebrates. In the original description of 
Squalodon, Grateloup held the view that this rostral fragment from 
Leognan, France, belonged to some large saurian related to Jguanodon. 
Following the anouncement of this discovery, Von Meyer * called at- 
tention to the teeth of this fossil, and concluded that the specimen was 
referable to some flesh-eating cetacean. A year later, Grateloup‘ 
concurred in this opinion. One other specimen should be mentioned in 
this connection, but, unfortunately, its relationships are quite uncer- 
tain. This specimen consists of a single tooth which was thought to 
bear resemblance to some pinniped by Von Meyer ® and named Pachy- 
odon mirabilis. Although this name has two years’ priority over that 
of Grateloup’s it should not be revived in this sense until the tooth is 
1Scilla, A., La Vana Specvlazione distingannata dal Senso, Naples, p. 123, pl. 12, fig.1, 1670; idem 
De Corporibus Marinis Lapidescentibus quae defossa Reperiuntur, Rome, p. 54, pl. 12, fig. 1, 1759. 
*Grateloup, J. P.S., Actes Soc. Linn. de Bordeaux, vol. 11 for 1839, No. 56, p. 346, 1840. 
3 Meyer, H. von, Neues Jahrbuch fiir Mineralogie, Stuttgart, pp. 587-588, 1840. 
4Grateloup, J. P.S., Idem., pp. 567-568, 1841. 
5Meyer, H. von, Idem., p. 414, 1848. 
No. 2462—PROCEEDINGS OF THE U. S. NATIONAL MUSEUM, VOL. 62, ART. 6. 
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