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CHAPTER VII

A SYNOPTIC CLASSIFICATION OF THE REPTILIA

ANAPSIDA. Temporal region of skull roofed over, or secondarily emarginated, not perforated.
1. Cotylosauria. Skeleton primitive; two coracoids^[1]; at least eighteen dorsal vertebrae, their ribs not expanded.
  1. Seymouria. Most primitive; teeth conical, in single row; intertemporal and otic notch. Insectivorous. Lower Permian.
  2. Diadectosauria. Teeth heterodont, the posterior transversely molariform, crushing. Malacophagous. Lower Permian.
  3. Labidosauria. Teeth anisodont, in two or more rows posteriorly; no supratemporal; interparietal on posterior surface. Lower Permian.
  4. Limnoscelis. Teeth anisodont, conical, in single row; interparietal on dorsal surface. Tail long. Lower Permian.
  5. [Pantylosauria. Teeth blunt or pebble-like, in single rows in upper jaw and dentary, numerous on palate and coronoid; interparietals large on dorsal surface. Lower Permian.]
  6. Pariasauria. Teeth anisodont, the posterior flattened [compressed] and crenulate; an acromion. Middle and Upper Permian.
  7. Procolophonia. Incisors conical, posterior teeth transverse, crushing; no supratemporal; interparietal obsolete or absent. Triassic.
2. Eunotosauria. Skeleton primitive; two coracoids, ten dorsal vertebrae, their ribs expanded to meet on the dorsum, and a dermal layer of bony plates. Middle Permian.
3. Testudinata (Chelonia). Skeleton not primitive; a single coracoid; ten dorsal vertebrae, their ribs expanded to meet on the dorsum or a dermal layer of bony plates.
  1. Amphichelydia. No mesoplastra. Cervical vertebrae amphicoelous or concavo-convex, neck not retractile. Upper Triassic to Cretaceous.
  2. Pleurodira. Neck retracted laterally; pelvis united with plastron. Jurassic to Recent.
  3. Cryptodira. Neck retracted vertically; carapace with peripheral plates. Jurassic to Recent.
  4. Trionychoidea. Neck retracted vertically; no peripheral plates. River turtles. Cretaceous to Recent.

↑ [But see footnote on page 126.—Ed.]

[1] [But see footnote on page 126.—Ed.]

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