PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. 62. 
/'. At least five of the molars in each upper jaw with anterior and pos- 
terior cutting edges serrated by well-defined accessory cusps. 
Molar crown high, ornamented with coarse striae (France). 
Squalodon typicus, new species [=Squalodon grateloupii Authors]. 
Jf?. Less than five of the molars in each upper jaw serrated by well- 
defined accessory cusps on both cutting edges. Roots of some of 
the molars long, and in some instances there is an indication of a 
thin isthmus which is, however, short. 
g'. Molar crown high, slightly incurved toward apex. Molars not 
constricted below enamel crown. Enamel surface of premolars 
ridged or fluted. 
h'. Accessory cusps present on both cutting edges of posterior 
molars, though not prominent. Premolars with elongate conic 
crowns, slightly compressed, forming an obtuse angle with 
root; enamel surface of crown fluted. Roots of some of the 
premolars united by a thin isthmus for a considerable portion 
of their length. Roots of incisors lodged entirely in the 
premaxillaries; roots of canines lodged in maxillae 
9 j bey 
Dental formula: 7. a, (o¥ gp pot m. ed 
3-3 1-1 4-4 6-6 
i!. Width of rostrum at base, 140-144 mm.; width of rostrum at 
anterior extremities of maxillae, 60mm. Length of rostrum 
in advance of maxillary notch slightly less than twice 
length of cranium posterior to notch. Orbital apophysis 
of supraorbital process of frontal rounded. Frontals forming 
a narrow band across the vertex of skull, conspicuously 
overlapped by ascending processes of maxillae. Mesorostral 
channel open. Nasals rudimentary. Ascending processes 
of premaxillae extending slightly posteriad to external 
narial openings, the distance equivalent to less than an- 
terior breadth of exposed surface of frontals on vertex. 
Supraoccipital wide, somewhat more than one-half greatest 
width of skull across squamosals, and forming a shallow 
‘‘W”’ shaped outline superiorly (France). 
Squalodon bariensis bariensis. 
(Italy) Squalodon bariensis bellunensis. 
?, Rostrum relatively wider at base. Frontals forming a wider 
band across the vertex of the skull. Supraoccipital appar- 
ently wider, rounded superiorly and not forming a ‘‘W”’ 
shaped outline (Italy)..... Squalodon bariensis latirostris. 
D?. No accessory cusps on anterior cutting edges of molars (so far as known). 
d'. Molars not provided with sawlike cutting surfaces on either cutting edge. 
e'. Roots of molars divergent at base, not united by a thin isthmus. 
J’. Anterior and posterior cutting edges of premolars distinctly sawlike. 
Incisors ornamented with coarse longitudinal striae or fluted. 
Roots of molars long, curving posteriorly and approximately 
equally distant from each other throughout their length; the roots 
are longer than maximum breadth of crown and the posterior 
roots of some of the molars equal more than twice the height of 
crown. Accessory cusps on posterior cutting edges of molars well 
developed. 
3-3 = 1-1 5-5 - 
Dental formula: 7.—; c. —; pm. —-; m. palit Het 
3-3 1-1 4-4 ?-6-+ 
Squalodon antverpiensis. 
