释义 |
Definition of gerontic in English: geronticadjective dʒɛˈrɒntɪkjəˈrän(t)ik Relating to old age, elderly people, or senescent animals or plants. Example sentencesExamples - The gerontic whorl of gastropod genera of the subfamily Mitchelliinae is twisted both outwards and backwards, but not upwards as in members of the subfamily Scoliostomatinae.
- These differences are not taken to be sufficient to merit recognition of a new species as they may be the result of ecophenotypic variations or gerontic developments in A. gigas.
- Rapid growth of the inner and basal parts of the apertural margin during their late shell ontogeny caused twisting of the gerontic whorl both outwards and backwards.
- In summary, examples of deviation from regular tight coiling during late shell stages and the development of a free gerontic whorl may be found in all known Cambrian-Devonian gastropod subclasses.
- A gerontic specimen, more than 8 mm wide, shows the development of high, elevated, bladelike accessory septa.
- A permesothyrid foramen is commonly associated with globular, gerontic forms within a single species population.
- Scattered undulose presepiments, disrupting as many as ten major septa, present in some adult and all gerontic specimens.
- The increasingly low relief of the anterior border with a narrow curvature of the anterior border furrow close to the anterior branches of the facial suture is certainly a gerontic feature.
- Specimens of Titanoplina were originally thought to be gerontic representatives of Proplina sibeliusi.
- None of the morphotypes are identical to the forms of A. concentricus and A. tamurai, especially because the latter species has a posterior radial groove and irregular ribs in gerontic individuals.
- However, this physical process cannot result in the simplification of septal folding in gerontic conchs.
- The gerontic aperture is narrowly elongated in species of Eoscoliostoma, but rather circular in Scoliostoma species.
- A few large specimens were known in 1986, however, these were thought to represent gerontic individuals.
- The feature has been considered to be a gerontic characteristic and of no systematic importance.
- This interpretation is also indirectly supported by the close stratigraphic occurrence (Early and Middle Devonian) of these gastropod genera having such an unusual gerontic aperture.
- The new species has also established that the strong revolving internal rib of Endoptygma is not a gerontic character.
Origin Late 19th century: from Greek gerōn, geront- 'old man' + -ic. Definition of gerontic in US English: geronticadjectivejəˈrän(t)ik Relating to old age, elderly people, or senescent animals or plants. Example sentencesExamples - Rapid growth of the inner and basal parts of the apertural margin during their late shell ontogeny caused twisting of the gerontic whorl both outwards and backwards.
- This interpretation is also indirectly supported by the close stratigraphic occurrence (Early and Middle Devonian) of these gastropod genera having such an unusual gerontic aperture.
- The increasingly low relief of the anterior border with a narrow curvature of the anterior border furrow close to the anterior branches of the facial suture is certainly a gerontic feature.
- The feature has been considered to be a gerontic characteristic and of no systematic importance.
- Specimens of Titanoplina were originally thought to be gerontic representatives of Proplina sibeliusi.
- In summary, examples of deviation from regular tight coiling during late shell stages and the development of a free gerontic whorl may be found in all known Cambrian-Devonian gastropod subclasses.
- A gerontic specimen, more than 8 mm wide, shows the development of high, elevated, bladelike accessory septa.
- The gerontic aperture is narrowly elongated in species of Eoscoliostoma, but rather circular in Scoliostoma species.
- A few large specimens were known in 1986, however, these were thought to represent gerontic individuals.
- These differences are not taken to be sufficient to merit recognition of a new species as they may be the result of ecophenotypic variations or gerontic developments in A. gigas.
- The new species has also established that the strong revolving internal rib of Endoptygma is not a gerontic character.
- The gerontic whorl of gastropod genera of the subfamily Mitchelliinae is twisted both outwards and backwards, but not upwards as in members of the subfamily Scoliostomatinae.
- However, this physical process cannot result in the simplification of septal folding in gerontic conchs.
- A permesothyrid foramen is commonly associated with globular, gerontic forms within a single species population.
- Scattered undulose presepiments, disrupting as many as ten major septa, present in some adult and all gerontic specimens.
- None of the morphotypes are identical to the forms of A. concentricus and A. tamurai, especially because the latter species has a posterior radial groove and irregular ribs in gerontic individuals.
Origin Late 19th century: from Greek gerōn, geront- ‘old man’ + -ic. |