Scleral tattooing including blindness, of the procedure and warns that it should not be performed without a professional. Scleral tattooing is still a new body modification, and potential longterm effects have therefore still not manifested themselves. In 2009 the Oklahoma Senate passed Senate Bill 844, filed by Oklahoma Senator Cliff Branan and supported by the Oklahoma Academy of Ophthalmology, to make it illegal to tattoo the sclera of the eye. Scleral tattooing Scleral tattooing is the practice of tattooing the sclera, or white part of the human eye. The dye is not injected into the tissue, but between two layers of the
Arthropod eye curved surface. Later designs used graduating lens sizes. The third eye morphology of trilobites, called the abathochroal, was found only within the Eodiscina. This morphology consisted of up to 70 much smaller lenses. The cornea separated each lens, and the sclera on each lens terminated on top of each cornea. The eye morphology of trilobites is useful for determining their mode of life, and can function as palaeoenvironmental indicators. The horseshoe crab has traditionally been used in investigations into the eye, because it has relatively large ommatidia with large nerve fibres (making them easy to experiment on). It also falls