ILLUSTRATIONS. 



PLATES. 



PAGE. 



1. Views along Mazon Creek, Illinois 12 



2. Drawing of type specimen of Micrerpeton caudatum Moodie, from the Coal Measures of Mazon Creek. . 52 



3. Specimens of Eumicrerpeton parvum, Erpetobrachium mazonensis, Erierpeton branchialis, Mazonerpeton 



longicaudatum, and Amphibamus grandiceps 58 



4. (i and 2) Vertebrae of Spondylerpeton spinatum Moodie. (3) Type specimen of Mazonerpeton costatum 



Moodie. (4) Type skeleton of Cephalerpeton ventriarmatum Moodie. (5 and 6) The halves of the 



nodule containing a practically complete skeleton of Amphibamus grandiceps Cope 60 



5. (i) A reconstruction of the Coal Measures branchiosaurian, Eumicrerpeton parvum Moodie, a small 



primitive salamander 64 



(2) A restoration of the branchiosaurian, Mazonerpeton, based on two specimens 64 



6. Dendrerpeton acadianum Owen. Mandibles, parts of anterior extremities, humerus, etc 68 



7. Hylerpeton dawsoni Owen. Mandible, teeth, rib, and bones of anterior extremity. Bones of pelvis and 



posterior limb and bony scales 72 



8. Fritschia curtidentata Dawson. Bones of skull and anterior extremity, bony rods of belly, of pelvis, and 



posterior extremity 76 



9. Hylonomus lyelli Dawson. (i) maxillas and skull bones; (10) sternal bones; (2) mandible; (3) humerus, 



ribs, and vertebras; (4) posterior limb; (5) pelvis; (6) caudal vertebras 78 



10. Hylonomus latidens Dawson. Skull, portion of skeleton, foot, scapular, and sternal bones, humerus and 



rib, believed to belong to this species. Erect tree, Coal formation, of Nova Scotia 80 



11. Hylerpeton longidentatum Dawson. Mandible and other bones. Erect tree, Coal formation 82 



12. Smilerpeton aciedentatum Dawson. Mandible, portions of skull, scales, and various bones. Erect tree, 



Coal formation 82 



13. Dendrerpeton oweni Dawson. Skull, mandible, and bones of anterior limbs, posterior limb, pelvis, and 



bony scales 100 



14. (i and 2) Amphibamus grandiceps Cope, from the Mazon Creek shales 106 



(3) Sauropleura (Colosteus) scutellata Newberry, from the Linton Coal Measures, the first known of the 



Ohio Coal Measures Amphibia; at first ascribed by Newberry to the fishes, but later correctly identi- 

 fied by Cope 1 06 



(4) Type of Diceratosaurus (Ccraterpeton) punctolineatus Cope, from the Linton Coal Measures 106 



15. (i) Dorsum of skull of Diceratosaurus punctolineatus (Cope), from the Coal Measures of Lint<m, ( >hi<>. . 1 14 



(2) Ventral surface of skull of Diccratnsaurus punctolineatus (Cope), from the Coal Measures of Linton . . 114 



(3) Pectoral girdle of Dieeratosaurus punctolineatus (Cope), from the Coal Measures of Linton 114 



(4) Cervical or anterior dorsal vertebra of Diceratosaurus punctolineatus (Cope), from the Linton Coal 

 Measures 114 



iff. (i) Type specimen of Diceratosaurus punctolineatus Cope 1 16 



(2) Skull of Sauropleura longidentata Moodie, from the Coal Measures of Linton, Ohio 116 



(3) Mandible of Sauropleura longidentata Moodie, from the Coal Measures of Linton, Ohio 1 16 



(4) Type specimen of Sauropleura enchodus Cope, from the Coal Measures of Linton, Ohio 1 16 



(5) Additional specimen of Diceratosaurus punctolineatus Cope, from the Coal Measures of Linton, Ohio. 116 



17. Type of Saurerpeton lathithorax Cope 126 



18. (i) Type of Erpetosaurus sculptilis Moodie, from the Cannelton Shales of Pennsylvania 132 



(2) Skeletal elements of Eryops sp. indet., from the Pittsburgh Red Shale at Pitcairn 132 



(3) Amphibian footprints, Dromopus aduncus Branson, from the Mississippian shales of Giles County, 

 Virginia 132 



(4) Type of Thinopus antiquus Marsh, amphibian footprint from the Devonian of Pennsylvania 132 



19. Type of Ctenerpeton alveolatum Cope, from the Coal Measures of Ohio 134 



20. (i) Skull of Erpetosaurus minutus Moodie, from the Cannelton slates of Pennsylvania 134 



(2) Skull and anterior part of body of Ptyonius pectinatus Cope, from the Coal Measures of Linton 134 



(3) Skeleton of Eosauravus copei Williston, from the Coal Measures of Linton. "The oldest known reptile 

 from North America" and closely related structurally to the Microsauria 134 



(4) Part of ventral scutellation and ribs of Sauropleura digitata Cope, from the Coal Measures of Linton . 134 



viii 



