proganosauria

from The Century Dictionary.

• A group of extinct reptiles, of small or moderate size and aquatic habits, distantly related to the existing Hatteria. The skull is long, the teeth are slender, the vertebræ are expanded above and perforated for the notochord, and the pectoral and pelvic girdles are plate-like. The known genera are Mesosaurus and Stereosternum, from the Permian.