art. 16. TWO SQUALODONTS FROM MARYLAND—KELLOGG. 19 
The other mandible mentioned by Pedroni* is less complete and 
belongs to the left side. An account of this specimen can be found 
under Squalodon bordae. The outlines of this mandible are quite 
unlike any squalodont thus far described, though at least one writer 
has recently held that it represents a valid species. 
There is a third mandible® which should be mentioned in this 
connection. It was formerly in the private collection of Delfortrie 
and was obtained at Leognan, France. The angle and the condyle 
are well preserved. The coronoid is damaged on the posterior mar- 
gin, and two serrate teeth are present in the ramus. No question 
has ever been raised regarding the relegation of this mandible to the 
squalodonts. It can hardly belong to the same specific form as 
either of the above mentioned mandibles from Leognan. The thin- 
ness of the horizontal ramus, the restriction of the symphysis to the 
inferior portion of the ramus, and the general appearance of the 
mandible as a whole suggest a distinct species. 
A fourth specimen found in the “grés marin” at Leognan, France, 
and consisting of a nearly complete left mandible that possesses five 
serrate molar teeth was referred to Squalodon grateloupr™ by Delfortrie. 
The illustration accompanying Delfortrie’s article shows that the an- 
terior edges of the second, third, and fourth two-rooted molariform 
teeth are provided with sawlike cutting surfaces and that the fifth 
and sixth are serrated by accessory cusps on both anterior and pos- 
terior edges. An alveolus for a seventh two-rooted tooth is present 
and is separated by an interval of 8 mm. from the alveolus for the 
sixth tooth. The mandible, as preserved, is 750 mm. in length and 
conforms in general proportions to that of Squalodon calvertensis. 
The horizontal ramus is deeper than that of the Maryland Squalodont. 
Delfortrie remarks that this mandible appears to have belonged to a 
Squalodon of larger size than those previously discovered at Leognan. 
As the situation now stands the rostral fragment described by 
Grateloup remains without a valid name unless it can be shown 
that Squalodon bordae represents the same species. In view of the 
absence of an associated jaw and skull from the sandstone formation 
at Leognan, France, and the fact that at least two and possibly three 
types of squalodont mandibles are known from the Leognan deposits, 
it is advisable to propose the name, Squalodon typicus, new species, 
for the rostral fragment described by Grateloup as Squalodon. The 
allocation of the mandibles will best await future discoveries. 
81 Pedroni, P. M., jr., Actes Soc. Linn. Bordeaux, vol. 14, pp. 107-109, 1845; Gervais, P., Zool. et 
Paléont. franc, Paris, ed. 1, vol. 1, p. 153, pl. 41, fig. 8 [reversed] 1848-1852. 
82 Fischer. P., Actes Soc. Linn, de Bordeaux, vol. 27, livr. 1, pp. 12-16, pl. 2, figs. 3a, 3b, 3c, 3d, 1869; 
Van Beneden, P.J., and Gervais, P., Ostéographie des Cétacés vivants et fossiles, Paris, p, 446, pl. 28, 
figs. 4, 4a, 1880. 
88 Delfortrie, E., Actes Soc. Linn. de Bordeaux, vol. 27, livr. 2, pp. 133-136, pl. 5, 1869. 
