[Periodically striated structures in the subcommissural organ of Clemmys caspica leprosa (Chelonia, Testudinidae) (author's transl)].

On a study of the most rostral part of the optic tectum of Clemmys caspica leprosa a periodically striated structure was detected at the subcommissural organ (SCO). It has been made a detailed analysis about its topographical relationship with vessels and with hypendyma, and also about its own periodical pattern of structure. This finding was also considered on a comparative point of view, keeping in mind the previous observations by some authors upon the rat's SCO and other related findings outside the central nervous system. Finally a functional interpretation is discussed.