"vestigial." YourDictionary, n.d. Web. 14 January 2019. <https://www.yourdictionary.com/vestigial>.
vestigial. (n.d.). Retrieved January 14th, 2019, from https://www.yourdictionary.com/vestigial
Relating to a body part that has become small and lost its use because of evolutionary change. Whales, for example, have small bones located in the muscles of their body walls that are vestigial bones of hips and hind limbs.
Heider bryonic membranes are vestigial or entirely wanting.
In some Psocidae the wings are in a vestigial state, and the fully winged species rarely if ever fly.
In the Malacostraca it is absent in the adult, or persists only in a vestigial condition, as in some Decapoda and Schizopoda.
17, C, a); he suggests they may represent vestigial structures pointing back to some ancestral form beyond the limits of the present group. The Gnetales probably had a separate origin from the other Gymnosperms; they carry us nearer to the Angiosperms, but we have as yet no satisfactory evidence that they represent a stage in the direct line of Angiospermic evolution.