sentences:  Goodrich did not give them ranks, and treated them exactly as if they had phylogenetic definitions, using neither contents nor diagnostic characters to decide whether a given animal should belong to Theropsida, Sauropsida, or something else once its phylogenetic position was agreed upon.Goodrich also opined that the name Reptilia should be abandoned once the phylogeny of the reptiles would be better known.The principle that only clades should be formally named became popular in some circles in the second half of the 20th century.