Spider are apparently absent. In some species, the exocuticle of the legs and prosoma is modified by a tanning process, resulting in brown coloration. Bilins are found, for example, in "Micrommata virescens", resulting in its green color. Guanine is responsible for the white markings of the European garden spider "Araneus diadematus". It is in many species accumulated in specialized cells called guanocytes. In genera such as "Tetragnatha", "Leucauge", "Argyrodes" or "Theridiosoma", guanine creates their silvery appearance. While guanine is originally an end-product of protein metabolism, its excretion can be blocked in spiders, leading to an increase in its storage. Structural colors
The Perfumed Garden and amusement. According to the introduction of Colville's English translation, Muḥammad ibn Muḥammad al-Nafzawi probably wrote "The Perfumed Garden" sometime during the twelfth century. Sheikh Nefzawi, full name Abu Abdullah Muhammad ben Umar Nafzawi, was born among the Berber Nefzawa tribe in the south of present-day Tunisia. He compiled at the request of the Hafsid ruler of Tunis, Abū Fāris ʿAbd al-ʿAzīz al-Mutawakkil, the present work. The reputation acquired by this work in the Arab world was similar to that of the "Arabian Nights". "The Perfumed Garden" first became widely known in the English-speaking world through a translation from the