218 University of Kansas Geological Survey. 



PLATE XXIV. — Fig. 1, right pterygoid of Platecarpus coryphaeus, from be- 

 low: fig. 2, premaxilla of same, from below; fig. 3, the same, from above; 

 fig. 4, postorbitofrontal of same, from within ; fig. 5, left jugal of same, from 

 without; fig. 6, sternum of Clidastes velox Marsh, after Marsh; fig. 7, left 

 quadrate of same, from without. 



PLATE XXV. — Fig. 1, left maxilla of Platecarpus coryphceus, from without; 

 fig. 2, the same, from within ; fig. 3, prefrontal of same ; figs. 4, 5, trans- 

 verse bones of same; fig. 6, posterior part of mandible of Baptosaurus 

 onchognathus, after Merriam. 



PLATE XXVI. — Platecarpus coryphaeus. Fig. 1, parietal, from above; fig. 

 2, frontal, from above; fig. 3. frontal, from below; fig. 4, left prosquamosal, 

 from without. 



PLATE XXVII. — Upper figure, posterior view of skull of Platecarpus cory- 

 phceus; fig. 1, radius of Clidastes ivestii, la, ulna ; fig. 2, radius of C. tor- 

 tor, 2a, ulna of same ; figs. 3, 4, radii of C. velox; 3a, 4a, ulnse of same. 



PLATE XXVIIL— Fig. 1, quadrate of Clidastes velox, from within ; fig. 2, the 

 same, from without ; fig. 3, the same, from in front ; fig. 4, the same, from 

 behind; fig. 5, pterygoid tooth of Platecarpus coryphaeus, enlarged; fig. 

 6, mandibular tooth of Clidastes tortor, enlarged; fig. 7, mandibular tooth 

 of Platecarpus coryphaeus, enlarged; fig. 8, radius of Platecarpus cory- 

 phaeus. 



PLATE XXIX. — -Fig. 1, mandibular tooth of Tylosaurus proriger, from within, 

 showing socket of successional tooth, enlarged ; fig. 2, posterior cervical 

 vertebra of Clidastes tortor, from behind, showing zygantrum; fig. 3, 

 sclerotic plates of Platecarpus coryphaeus, enlarged; fig. 4, anterior end 

 of vomer of Platecarpus coryphozus, from without, enlarged; fig. 5, un- 

 determined bone of Platecarpus coryphaeus, enlarged. 



PLATE XXX. — Brachysaurus overtoni. Fig. 1, mandibular tooth, natural 

 size; fig. 2, frontal bone, from above; fig. 3, left quadrate, from within; 

 fig. 4, posterior cervical vertebra, from behind; 4a, the same from below; 

 fig. 5, median caudal vertebra, from behind; fig. 6, humerus; fig. 7, unde- 

 termined paddle bone. Except fig. 1, one-half natural size. 



PLATE XXXI. — Figs. 1, 2, 3, hyoid bone of Platecarpus, natural size, after 

 Marsh: figs. 4, 5, pygal vertebra of Platecarpus coryphceus, from behind 

 and from the side ; fig. 6, coracoid and scapula of Clidastes velox, from 

 behind; fig. 8, part of hind paddle of Mosasaurus lemoinii, after Dollo, 

 much reduced. Other figures one-half natural size. 



PLATE XXXII. — Left figure, part of left paddle of Mosasasurus horridus, 

 one-third natural size: h, humerus; R, radius; U, ulna: I, first meta- 

 carpal ; right figure, right quadrate of Mosasaurus horridus, from within, 

 two-thirds natural size. 



PLATE XXXIII. — Incomplete left front paddle of Clidastes velox: C, cora- 

 coid; *S', scapula: Mm, humerus; I, first digit; V, fifth digit. 



