220 University of Kansas Geological Survey. 



PLATE XLVI. — Left humerus of Platecarpus coryphceus, from below ; fig. 2, 

 distal end of same ; fig. 3, the same, from above ; fig. 4, proximal end of 

 same ; s, scapula of Tylosaurus dyspelor, from without ; e, coracoid of 

 same, from without; s, right scapula of T. dyspelor, from without; c, 

 coracoid of same. 



PLATE XLVII. — Left-hand figure, frontal bone of Clydastes tortor, from 

 above ; right-hand figure, right pelvic bones of Platecarpus simm.us, after 

 Marsh, from without : a, ilium ; b, ischium ; c, pubis ; d, femur. 



PLATE XLVIII. — Coracoid and front paddle of T. proriger, as imbedded in the 

 chalk, the left-hand figure, outlines of the bones as determined from the 

 two sides of the slab. 



PLATE XLIX. — Left pelvic bones of T. proriger, as imbedded in the same slab 

 as the preceding ; the lower right element is the pubis ; the left, the ischium. 



PLATE L. — Hind paddle of Tylosaurus proriger, in matrix: /, femur; /', 

 fibula; t, tibia; fa, tarsal; me, metatarsal; Vm, fifth metatarsal. 



PLATE LI. — Platecarpus coryphceus, in matrix: fig. 1, right humerus, from 

 below; fig. 2, left coracoid, from without ; fig. 3, right scapula, from within ; 

 fig. 4, left humerus, from above ; fig. 5, carpal ; fig. 6, radius ; fig. 7, 

 cervical hypapophysis ; figs. 8, 9, cervical ribs; figs. 10, 11, 12, thoracic 

 ribs; fig. 13, cartilage. 



PLATE LII. — Platecarpus coryphaeus: fig. 1, left humerus, from below; 

 fig. 2, ulna; fig. 3, right lateral piece of atlas, from within. 



PLATE LIII. — Fig. 1, thirty-eighth vertebra of Clidastes ivestii, from behind; 

 fig. 2, the same, from below. 



PLATE LIV. — Pygal vertebras, from behind : fig. 1, Tylosaurus sp., from Fort 

 Pierre; figs. 2, 3, Platecarpus coryphceus; fig. 4, Clidastes tortor; fig. 

 5, anterior caudal vertebra of same. 



PLATE LV. — Bones of Tylosaurus proriger, in matrix: fig. 1, radius; fig. 2, 

 humerus; fig. 3, coracoid; fig. 4, cartilage. 



PLATE LVL— Figs. 1, 2, 4, femora of Platecarpus coryphaius ; fig. 3, radius; 

 fig. 5, radius, carpus, and part of metacarpus, showing exostosial growth. 



PLATE LVIL— Figs. 1, 2, radii of Platecarpus sp.?; fig. 3, tibia of Clidastes 

 sp.; fig. 4, tibia of Platecarpus coryphaeus; fig. 5, fibula of same; fig. 6, 

 metatarsal of same; fig. 7, fifth metatarsal of same; figs. 8, 9, 10, tarsals 

 of same. 



PLATE LVIIL— Figs. 1. 2, 3, radii of Platecarpus coryphceus; figs. 4, 5, 6, 

 ulna? of same : fig. 7, radial carpal of same ; fig. 8, ulnar carpal of same ; 

 figs. 9, 10, distal carpals of same. 



PLATE LIX. — Tylosaurus dyspelor: fig. 1, humerus; fig. 2, radius; fig. 3, 

 ulna ; figs. 4-8, metacarpals and phalanges. 



