Fig. 2
Head development of Russian sturgeon (Acipenser gueldenstaedtii). AI rudiment of 1st pair of visceral arches, AV auditory vesicle, BR, brain rudiment, CuD duct of Cuvier, E eye, ER eye rudiment, HG hatching gland, L loop formed by the anterior part of the pronephric duct, Mc mesencephalon, MyC myelencephalon cavity, NF neural fold, NG neural groove, NP neural plate, OS olfactory sac, Pc prosencephalon, PD pronephric duct, Rc rhombencephalon