O. G. Dely szerk.: Vertebrata Hungarica 7/1-2. (Budapest, 1965)

Tóth, J. ; Rácz, B.: A new method of marking fish with a plastic (PVC) opercular tag 1-8. o.

Description of the tag and the marking process The tag consists of a label stack between two plastic /PVC - polyvinychlorid/ plates, and a T-shaped suspending or fastening portion /fig.l/. 2 The label, reproduced by photographic means , will be coated with a thin celluloid layer, to protect it from accidental infiltration of water. The tag itself is made of 0.2 mm thick, colorless PVC foil /the so-called „gardener's foil"/, the two bits being glued together by cyclohexanone. The tag, of a given shape and size, is cut by a sharp tool from the foil. The affixing wing of the tag is thicker /shown by shade-lines in the Figure/, to prevent the loosening or falling out of the mark. The marking proper - the attaching of the tag - is made by a marking tweezers. Any flat pincers is suitable, but its ends should be filed sharp and straight. It is essential that the pincers be flat and its straight tip 5 mm wide. 2 The method of reproduction was elaborated by our colleague E.SÁRFY, for his own marking process, and he was kind enough to offer it also for our purposes. Por his generous help, we express our thanks also in this place. The method of reproduction is, in essence, as follows. The large size label is drawn with indian ink, showing also the name and address of the institution responsible for the marking, in our case the „Fishery Department, Gödöllő". A suitable place is left free for the serial number, indispensable for individual marking. After photographing it, copies are made in a size to allow the typing in of numbers in the place preserved for the serial number. Forty to fifty of such copies are glued on a sheet of cardboard equalling the size of a typewriter sheet, then the place of the serial number is cut out of eacb copy. We have now a lasting master model for reproduction, under which another sheet of paper, with typewritten serial numbers /placed and arranged according to the holes cut in the labels/, can be placed. The master model, with the serial numbers showing in the appropriate place in the labels, can now be photographed again, the typewritten sheet with other serial numbers /in increasing order/ changçd, and further photographs made. The copies can then be made according to the required size*