Parallelism between the ontogenetic and the phyletic vital force, 687.
This is true of both branches of evolution, individual and phyletic.
In this case there is therefore no necessity for assuming a phyletic vital force.
This phyletic line retained the larval characters and breeding call of the prototype.
The tissue-soul (histopsyche): third stage of phyletic psychogenesis.
The frogs in this phyletic line retained the moderate size of the prototype and did not develop additional dermal bone.
Three stages in the life of the species, representing three phyletic stages of the genus.
The Agalychnis phyletic line has one kind of specialization for an arboreal existence.
From these data alone, we may venture to infer the occurrence of four chief stages in the phyletic development of the genus.
In nearly all phyletic or class descriptions the word "symmetry" occurs, and its exact meaning must be understood.