Origin and Evolution of Angiosperms , 1976. Contemporary Botanical Thought, p. 97, 1961. Journal of Geological Education , May 1988, p.143. The absence of such ancestral forms leaves many problems of the amphibian-reptilian transition unanswered. Instead of gradual change, fossils of each intermediate species appear fully distinct, persist unchanged, and then become extinct.
Transitional forms are unknown.
Natural History November 1983, p. 77.