part of part of in taxon Chondrichthyes Dipnomorpha orbit of skull scleral ossicle scleral ossicle The function of these elements is to support the eye from within the sclera; scleral ossicles play an additional important role during accommodation in terrestrial vertebrates (Lemmrich, 1931; Walls, 1942; King and McLelland, 1984). A bony plate around the eyes, are situated at the corneal-scleral limbus. They do not articulate with other elements of the skull. Typically, the scleral ossicles overlap the rim of a cup of scleral cartilage that supports the eyeball. Situated near the equator of the eye and may slightly overlap the rim of scleral cartilage. sclerotic ossicle The distribution of scleral ossicles and scleral cartilage among verte- brate taxa is not the same. Some taxa (e.g., birds) have both elements; some only have one element (e.g., crocodiles only have a scleral cartilage); while others (e.g., snakes) have neither element (Walls, 1942) number of ossicles making up the sclerotic ring as well as the shape of both the individual plates and the sclerotic ring is variable among tetrapod taxa.... It is therefore extremely likely that scleral skeletal elements (ossicles and cartilage) of all rep- tiles (including birds) are homologous (but cannot be assumed for reptiles and teleosts) sclerotic bone SCTID:45632000 UBERON:0010290 scleral skeletal element facial skeleton