The development of the pretectal cell masses of the American water snake (Natrix sipedon).
D000818:Animals; D017812:Colubridae; D004622:Embryo, Mammalian; D004625:Embryo, Nonmammalian; D008636:Mesencephalon / Q000033:anatomy & histology*; D066250:Pretectal Region; D012911:Snakes; D014481:United States
EMBRYO; MESENCEPHALON/anatomy and histology; SNAKES