AWN 
SE 
to N Ounf WN HE 
N QDMA WD 
2 aa 
INDEX OF PLATES. 559 
PLATE 20. 
. Baéna emilie. Carapace of type. X04. No.1925 A. M.N. H. 
. Baéna emilie. Plastron of type. 0.4. 
PLATE 21. 
. Eubaéna cephalica. Skull forming type, upper aspect. * 1. No. 2110 Yale Univ. coll 
. Eubaéna cephalica. Same skull, lower aspect. % TI. 
. Chisternon hebraicum, Skull, upper aspect. * 1. No. 5961 A. M.N.H. 
. Chisternon hebraicum. Same skull, lower aspect. X 1. 
PLATE 22. 
Chisternon undatum. Carapace. 0.34. No. 3932 A. M.N. H. 
PLATE 23. 
_ Chisternon hebraicum. Skull, right side. x 1. No. 5961 A. M.N.H. 
. Bothremys cooki. Skull of type, lower surface. 08. Type in Rutgers College, N. J 
. Bothremys cooki. Lower jaw of type. X08. 
. Osteopygis chelydrinus. Seventh peripheral of type. 0.75. No. 1131 A. M.N.H. 
. Osteopygis chelydrinus. Same bone, inner surface. 0.75. 
. Osteopygis chelydrinus. Second left peripheral of type, outer surface. X 0.75. 
. Osteopygis chelydrinus. Same peripheral, inner surface. 0.75. 
PLATE 24. 
Thescelus insiliens. Carapace of type. * 4%. No.1108 A. M.N. H. 
PLATE 25. 
Thescelus insiliens. Plastron of type. X %. No. 1ro8A.M.N.H. 
PLATE 26. 
. Osteopygis gibbi. Rim of carapace of type, seen from below. * 0.23. Type in Yale 
Drawing furnished by U.S. Geol. Surv. 
. Osteopygis erosus. Sixth to tenth peripherals. * 0.27. No. 1130 A. M.N.H. 
. Osteopygis borealis. Seventh to eleventh peripherals. 0.27. No. 1132 A. M. N. KR. 
PLATE 27. 
. Osteopygis gibbi. Carapace of type. * %->. Type in Yale Univ. coll. 
. Osteopygis gibbi. Plastron of type. xX % +. 
PLATE 28. 
. Osteopygis chelydrinus. Third peripheral of type, outer surface. X 0.75. No. 113% 
A.M.N. H. 
. Osteopygis chelydrinus. Same peripheral, inner surface. * 0.75. 
. Osteopygis chelydrinus. Lower jaw, upper surface. 0.75. Part of type. 
. Osteopygis chelydrinus. Same jaw, right side. * 0.75. 
. Lytoloma angusta. Lower jaw accompanying type peripheral. x 0.6. No. 1133 A. M.N.H. 
. Lytoloma angusta. Peripheral forming type. * 0.6. No. 1133 A.M.N.H. 
. Lytoloma wielandi. Upper surface of front of skull, forming type. 08. Yale Univ. 
coll. Drawing from U.S. Geol. Surv. 
. Lytoloma wielandi. Same specimen, lower surface. * 0.8. 
PLATE 20. 
. Lytoloma wielandi. Type fragment of skull, seen from behind. 0.8. 
. Rhetechelys platyops. Skull forming type, upper surface. 0.4. Type in coll. Phila 
Acad. 
_ Rhetechelys platyops. Same skull, inferior surface. X 0.4. 
