In this paper are analysed the elytrae of a new species of the genus Oontelus and, for comparation, of Chalepus sanguinicollis ab. axilaris with a view to explain the origin of the transparent membrane of the perforations of the elytrae. The membrane is formed by the two epicuticulae of the uper~ and underside of the elytra, the two membranes adhere together closely by means of a adhesive mass. The thickness of the membrane of Oontelus mounts to 0,34~0,36 micron, that of Chalepus to 4~4,3 micra. This two described cases represent a typical for the law of the continuation of the cuticula on the ectodermal parts os insects whose formation, corresponding to the basical plan of construction of the body, does not allow any interruption.