The button-shaped seals are of considerable interest to the student of comparative archaeology, and they are certainly not Upper Egyptian in their origin. The earlier forms have, moreover, no affinity to the Mycenaean series of designs, and, as Mr. Petrie[105] has remarked, the spirals, butterfly, cuttlefish and other characteristic types are absent. On the other hand, they have several links which connect them to the Greek Island and Cretan class of seals, and also to some found in Italy, from which we may perhaps infer that they are of common origin.[106] An almost exact reproduction of some of these steatite buttons in clay actually occurs in the Italian _terramare_, and in the Ligurian cave deposits of neolithic and æneolithic periods. Mr. A. Evans writes, “The clay stamp from the _terramare_ of Montale in the Modenese, represented in fig. 52, the top of which is now broken, was probably once perforated, is not only analogous in form but bears a simple geometrical design almost identical with that on an early steatite button-seal from Knossos.”[107] [Illustration: Fig. 52.] [Sidenote: Material.] Specimens of button-seals have been found in gold, amethyst, carnelian, lapis lazuli, black steatite, steatite glazed blue or green, ivory, bone, and blue or green glazed pottery. The hemi-cylinders are only as yet known in steatite glazed blue or green. 3. SCARAB-SHAPED SEALS. [Sidenote: Scarab-shaped seals.] By far the commonest form of Egyptian seal was that cut in the shape of the scarabaeus beetle, hence its name, “Scarab” or “Scarabaeus,” from the Greek name of the insect, [Greek: skarabos] or [Greek: skarabeios] (Latin scarabaeus).[108] The beetle is represented standing on an elliptical base, on which is engraved in intaglio a hieroglyphic inscription or ornamental pattern. The seals of this class range in size from a fifth of an inch in length to four or even five inches, but the commonest size is about three-quarters of an inch, by half-an-inch broad and a quarter of an inch high. They are nearly always pierced longitudinally with a hole, the size of which is usually just sufficient to receive a thread or thin wire. [Sidenote: How used.] When the scarab-seal was used for sealing, it was simply pressed upon the clay destined to receive the impression, just as a signet is used at the present day. A large number of clay-sealings from scarabs have been found in different localities in Egypt, and bear witness to the manner in which this class of seal was used. [Sidenote: How mounted.] [Illustration: Fig. 53.]