198 MEMOIRS OF THE CARNEGIE MUSEUM. 
CHAPTER I. THE CHALICOTHEROIDEA. 
Order UNGULATA Ray. 
Suborder PERISSODACTYLA Owen. 
Superfamily CHALICOTHEROIDEA Gill (1872). 
(Chalicotherodea Osborn (1898).) 
Principal Characters—Dentition buno-selenodont; upper incisors unknown; lower incisors 
three, or wanting; upper canines wanting; lower canines one, or wanting; premolars in all genera 
so far discovered reduced to three in both jaws; molars three in both jaws; premolar-molar series 
rapidly increasing in size backwards, especially in the upper jaw; long diastema between premolars 
and canines or incisors, as in Equus; skull ranging from brachycephalic to dolichocephalic in the 
various genera; auditory bulle remarkably developed; orbit open posteriorly; supra-orbital with a 
foramen as in Hquus, but even more developed; premaxillaries slender; horizontal ramus of man- 
dible narrowing anteriorly, ascending ramus broad and high. Cervical vertebre so far as known 
having, as in the Hqwide, a prominent keel on the ventral face of the centra, but even more strongly 
developed than in the latter family. Pelvis, so far as known, elongated, recalling that of the 
Artiodactyla. Third trochanter of the femur either present or absent. The relative length of the 
fore and hind limbs in some genera subequal, in other genera the hind limbs relatively much shorter 
than the fore limbs. Distal face of astragalus articulating with the navicular and cuboid, or with 
the navicular only. Distal extremities of the metapodials on the anterior face having a smooth 
convex surface for the articulation of the phalanges, on the posterior face provided with a strong 
median keel separating the sesamoidal facets. First and second phalanges, especially of the second 
digit of the fore foot frequently codssifying in adult specimens. Terminal phalanges deeply bifid. 
For nearly a century paleontologists have been more or less acquainted with 
the fragmentary remains of a group of curious extinct mammals, which were 
first found in the Tertiary of Germany and France, later in Greece, and with 
the progress of exploration in the Tertiary formations of Asia and North 
America. The first account of a portion of one of these animals was from the pen 
of the illustrious French naturalist, Baron Georges Cuvier, who in his ‘‘ Recherches 
sur les Ossemens Fossiles,” Vol. V, pp. 198-195 (1825), gives a description of the 
cast of a bifid claw-like bone, which had been sent to him by Herr Schleiermacher, 
the librarian and private secretary of the Grand Duke of Hesse, the original having 
been found at Eppelsheim. With pronounced firmness of conviction Baron Cuvier 
announced that this bone undoubtedly belonged to an Edentate, which, according 
to the analogies of recent forms, must have been “un pangolin gigantesque.”’ 
“Cet Onguéal n’a d’analogues dans la nature que ceux des pangolins, et d’aprés 
toutes les lois de coexistence it est impossible de douter que les rapports les plus 
marqués de |’animal qui le portoit n’étaient été avec ce genre de quadrupédes.” 
