GANODONTA (so named from the presence of bands of

See also:

• ENAMEL (formerly " amel," derived through the Fr. amail, emmll, esmail, from a Latin word smaltum, first found in a 9th-century life of Leo IV.)

enamel on the

See also:

• TEETH (O.E. Eel); plural of tooth, O.E. top)

teeth)  , a group of specialized North American Lower and Middle Eocene mammals of uncertain affinity . The group includes Hemiganus, Psittacotherium and Conoryctes from the Puerco, Calamodon and Hemiganus from the Wasatch, and Stylinodon from the Bridger Eocene . With the exception of Conoryctes, in which it is longer, the skull is short and suggests affinity to the sloths, as does what little is known of the limb-bones . The dentition, too, is of a type which might well be considered ancestral to that of the Edentata . For instance, the molars when first developed have tritubercular summits, but these soon become worn away, leaving tall columnar crowns, with a subcircular surface of dentine exposed at the summit of each . Moreover, while the earlier types have a comparatively full series of teeth, all of which are rooted and invested with enamel, in the later forms the incisors are lost, the cheek-teeth never develop roots but grow continuously throughout life . These and other features induced Dr J . L . Wortman to regard the Ganodonta as an ancestral suborder of Edentata; but this view is not accepted by Prof . W . B . Scott .

Teeth

provision-ally assigned to Calamodon have been obtained from the Lower Tertiary deposits of Switzerland . See J . L . Wortman, " The Ganodonta and their Relationship to the Edentata," Bull . Amer . Mus. vol. ix. p . 59 (1897); W . B . Scott, Mlammalia of the Santa Cruz Beds, Edentata," Rep . Princeton Exped. to Patagonia, vol. v . (1903-1904) . (R .