. Carnegie Institution of Washington publication. r. 15 A REVISION OF THE COTYLOSAURIA OF NORTH AMERICA Original description of type: "The teeth are more completely molar in their character than the species already described (£. alatui), being in the unworn con- dition as broad across the crown as the latter is high. In the transverse direction the crowns are two and a half times as long as wide. The extremities are rounded, and there is a median cusp extending across the crown; on each side of the cusp, the face of the crown is slightly concave. The enamel is strongly but finely wrinkled
. Carnegie Institution of Washington publication. r. 15 A REVISION OF THE COTYLOSAURIA OF NORTH AMERICA Original description of type: "The teeth are more completely molar in their character than the species already described (£. alatui), being in the unworn con- dition as broad across the crown as the latter is high. In the transverse direction the crowns are two and a half times as long as wide. The extremities are rounded, and there is a median cusp extending across the crown; on each side of the cusp, the face of the crown is slightly concave. The enamel is strongly but finely wrinkled. The series terminate abruptly in a tooth of half the transverse extent of the penultimate. Length of space occupied by the penultimate and ante-penultimate teeth M. .021; length of base of the penultimate .010; width of do. .024; elevation of crown, least .006; do. at cusp, .009. "This species is larger than those heretofore de- scribed, and the teeth are adapted for crushing harder Fig. 1.—Two maxillary teeth of D'*&«" u0A[es having perhaps a use like those of Placodus or molaris. XI. Type No. 4347 Am. Mus. UUUICS '""' 6 F K . „ Pycnodus. It is called D. molaris. Original description of paratype ("Proceedings American Philosophical Soci- ety," l880, p. 47): . , . , , c -, "The molar teeth are wider in this species than in any species of the family yet known The internal and external extremities of the crown are about equally wide and equally elevated, and there is a low median cusp. A portion of the grinding surface, both internal and external to the cusp, is horizontal; the surface of this portion is wrinkled. The last molar is smaller than the others The inner border of the maxillary bones forms a curved ridge on each side of the palate, which is separated by a groove from the vomer. The latter forms a median keel at the an- terior portion of the palate, where it supports two rows of small conica teeth. 1 he palatines have their
Size: 1729px × 1444px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
