Fig. 4

Embryonic and juvenile shells of some early Mississippian tainoceratids from Belgium. aVestinautilus sulciferus (Phillips, 1836), a 3360 (type of Koninck 1878, pl. 31, fig. 7), lateral view. bVestinautilus konincki (Orbigny, 1850), a3350 (type of Koninck 1878, pl. 30, fig. 1), lateral view. cVestinautilus cariniferusi (Sowerby, 1824), a3347 (type of Koninck 1878, pl. 28, fig. 5), lateral view. Arrow indicates end of the embryonic shell. Scale bar 1 cm