[Comparative morphological study of the prothallial development in Asplenium species].

This study concerns the comparative development of gametophytes of nine Asplenium species. Some of them are diploïd, others tetraploid. They were studied on a cytogenetic point of view by british workers who found parental relationships between these species. The morphological analysis of the gametophytic development permits to determine the definite stages on which the tetraploïd species like to the supposed diploid parents. The inherited morphological characteristics are also described, for instance: formation of the prothallial plate, form of the marginal hairs. This qualitative analysis of the gametophytic development is not sufficient to confirm the supposed parental relationships. Therefore, precisions are given by the results of the quantitative analysis of the prothallial development and the study of the vascularization of the young sporophytes; these results will be soon published.