The morphology of the pineal region in teleosts / Robert J. Terry.

  • Terry, Robert J. (Robert James), 1871-1966.
Date:
[1910]
Catalogue details

Licence: In copyright

Credit: The morphology of the pineal region in teleosts / Robert J. Terry. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Fig. 18. Transver.se section through the pineal region of an adult Opsanus. W.U.C., series no. 13, section no. 517. X 21. Velum Transversum. The appearance of the median lobe of the velum is much the same as that of the 19 mm. larva. The cov- ering epithelium consists of a single layer of long club-shaped cells, grouped into prominent tufts. The larger free end of the cell is often irregular, fringed or lacerated, sometimes rounded and regular. Neither cilia nor cuticulae are present, but long shreds of some substance extend from the ends of the cells into the ven- tricle there to become continuous with a coagulum which is al- ways found close about the velum. In the coagulum are rounded bodies and masses which are stained like the clubbed ends of the cells. The nucleus is located near the free end of the cell and, between it and the base, granules are sometimes to be seen which stain deeply. The epithelium rests upon a rather thick reticular membrane, separating it from numerous underlying blood-vessels.