. potentialities. They were free of the water. They could venture over the face of the earth and continue their kind in regions where the less efficient amphibians could not survive. Thus was born a mighty race. The earliest reptiles were very much like their amphibian ancestors. In fact, some of the most primitive reptiles were so very am- phibian-like that there has been a great deal of argument as to whether these basic rep- tiles might not more properly be regarded as advanced amphibians. So it goes. The more we know about the classification of animals, the less distinct become the lines o
. potentialities. They were free of the water. They could venture over the face of the earth and continue their kind in regions where the less efficient amphibians could not survive. Thus was born a mighty race. The earliest reptiles were very much like their amphibian ancestors. In fact, some of the most primitive reptiles were so very am- phibian-like that there has been a great deal of argument as to whether these basic rep- tiles might not more properly be regarded as advanced amphibians. So it goes. The more we know about the classification of animals, the less distinct become the lines of demarcation separating one form from another or one group from another. In other words, we find the intermediate stages which prove the validity of evolution. Certainly there could hardly be an ani- mal more exactly intermediate in its anatomical features between the amphibi- ans and the reptiles than the Permian genus, Seymouria (see-MOOR-e-ya), from the rocks known as the red beds of Texas. This animal approximates structurally the stem for all reptilian life; it is the "grand- father ; The reptiles may be classified in a broad, general way on the basis of skull design, as follows: a. Anapsida (an-APS-i-da) Skull roof solid, without any openings be- hind the eye. b. Synapsida (sine-APS-i-da) Skull roof perforated by a lower opening behind the eye bounded above by the postorbital and squamosal bones, c. Parapsida (par-APS-i-da) Skull roof perforated by an upper opening behind the eye, bounded below by the post- 48
Size: 1957px × 2554px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookpublishernewyork, booksubjectreptilesfossil
