Ancestrally sentence example
- The atrophy and total disappearance of ancestrally well-marked somites fre FIG.
- Lankester (2) was the first to suggest that (as is actually the fact in the Nauplius larva of the Crustacea) the prae-oral somites or prosthomeres and their appendages were ancestrally postoral, but have become prae-oral " by adaptational shifting of the oral aperture."
- It is commonly assumed that the Trachylinae are forms which have lost the alternation of generations possessed by them ancestrally, through secondary simplification of the life-cycle.
- If it is assumed that all these genera bore gonophores ancestrally, then medusa of similar type must have been evolved quite inde pendently in a great number of cases.