Histological images of the eye of a ball python ( Python regius ). Transversal histological section through the medial portion of the whole eye (A) and spectacle (B) stained with hematoxylin and eosin. Cornea (C), inner epithelium (IE), iris (I), lens (L), outer epithelium (OE), periocular scale (POS), retina (R), spectacle (S), stroma (STR), sub-spectacular space (SSS), and spectacular transition zone (TZ). Scale bar in (A) is 1 mm and 100 μm in (B). Histological image in (A) is from  and reprinted with permission from John Wiley and Sons.