Lateral views of normally developed embryos (A, B) and dorsolateral view of a bicephalic embryo (C). Inset in C – details of limb morphology. Note differentiated eye primordia in A and B with an evenly pigmented retina and centrally located lens primordia. dpo – days post oviposition, st – stylopodium, z – zeugopodium, au – autopodium, mes – mesencephalon, of – optical fissure, asterisk – limb, h – heart, t – tail, AER - apical ectodermal ridge.