Some modern lizards run this way on occasion, especially if they are in a hurry.
But the bodies of lizards are too long and their limbs too small and slender for this to be the usual mode of progress, as it seems to have been among the Dinosaurs.
ANIMALS OF THE AGE OF REPTILES.
LAND REPTILES.
DINOSAURS corresponding to the larger quadrupeds or land mammals of today.
CROCODILES, LIZARDS AND TURTLES still surviving.
SEA REPTILES.
PLESIOSAURS } corresponding to whales, dolphins, seals, ICHTHYOSAURS } etc., or sea-mammals of today.
MOSASAURS } FLYING REPTILES OR PTEROSAURS.
BIRDS WITH TEETH (scarce and little known).
PRIMITIVE MAMMALS of minute size (scarce and little known).
FISHES and INVERTEBRATES many of them of extinct races, all more or less different from modern kinds.
Fishes, large and small, were common in the seas and rivers of the Age of Reptiles but all of them were more or less different from modern kinds, and many belonged to ancient races now rare or extinct.
The lower animals or Invertebrates were also different from those of today, although some would not be very noticeably so at first glance.
Among molluscs, the Ammonites, related to the modern Pearly Nautilus, are an example of a race very numerous and varied during all the periods of the Reptilian Era, but disappearing at its close, leaving only a few collateral descendants in the squids, cuttlefish and nautili of the modern seas.

The Brachiopods were another group of molluscs, or rather molluscoids for they were not true molluscs, less abundant even then than in previous ages and now surviving only in a few rare and little known types such as the lamp-shell (_Terebratulina_).
_Insects._ The Insect life of the earlier part of the Age of Reptiles was notable for the absence of all the higher groups and orders, especially those adapted to feed on flowers.

There were no butterflies or moths, no bees or wasps or ants although there were plenty of dragonflies, cockroaches, bugs and beetles.

But in the latter part of this era, all these higher orders appeared along with the flowering plants and trees.
_Plants._ The vegetation in the early part of the era was very different both from the gloomy forests of the more ancient Coal Era and from that which prevails today.

Cycads, ferns and fern-like plants, coniferous trees, especially related to the modern _Araucaria_ or Norfolk Island Pine, Ginkgos still surviving in China, and huge equisetae or horsetail rushes, still surviving in South American swamps and with dwarfed relatives throughout the world, were the dominant plant types of that era.