Myledaphus bipartus, Cope, 1876

Lambe L. M., 1902, New genera and species from the Belly River Series (mid-Cretaceous), Geological Survey of Canada Contributions to Canadian Palaeontology 3, pp. 25-81 : 28-29

Myledaphus bipartus , Cope.

Plate XIX, figs. 1 and 2 .

Myledaphus bipartitus . Cope. 1876. Proc. Acad. Nat. Sci. Philadel., p. 260.

This species is represented by many teeth found separate in all cases. Their variation in size is considerable, the smallest measuring about 225 mm. on the longer diameter of the crown, whilst the largest collected has a diameter of 9 mm. in the same direction. The proportions of the majority of the specimens are nearly constant. Measurements taken from an average sized tooth almost coincide with those given by the author of the species in his original description. In the majority of the specimens the crown is irregularly striated in a direction at right angles to and on both sides of the line dividing it into halves although generally one half has fewer striations than the other. The crowns of some of the teeth are smoother than those of others, a dift'erence due probably to age.

Measurements of an average sized tooth.
M.
Length of tooth	0055
Long diameter of crown	0062
Short " "	0045
Length of root	0030
Long diameter of root	0042
Short " "	0030

Belly River series, Eed Deer river, 1898 and 1901.

Dr. Gr. M. Dawson collected a number of specimens on Belly river, N.W.T. (Nos. 40 and 41), in 1881, and Mr. Weston specimens in Irvine coulee, near Irvine station on the line of the C.P.E., in 1888.

Cope, in describing this g-euiis, was doubtful as to its affinities, biit states " that the form of the root recalls the Elasmobranchii, and that of the crown some of the rays. The types he recorded as from the Fort Union beds of Montana.

Figures

PLATE XIX. Fig. 1. Myledaphus bipartitus, Cope, pavement tooth, face of crown; enlarged four times. Page 28. Fig. 2. Side view of same tooth. g, crown; f, face of crown; r, root. Fig. 3. Lepidotus occidentalis, Leidy, outer surface of scale natural size. Page 29. Fig, 4. Monoclonius dawsoni, Lambe, lcft scapula and coracoid, internal view. (Provisionally associated with M. dawsoni); onefourth natural size. Page 60 Fig. 5. Monoclonius dawsoni, predentary bone, lateral view. (Provisionally associated with M. dawsoni); natural size. Page 63. Fig. 6. The same, viewed from above. s scapula; c coracoid; a, suture between scapula and coracoid; g, glenoid cavity; b, upper,, border d, anterior end; e, groove for dentary.