Figure 7
Presumptive streams of amniogenic somatopleural cell movement forming the amnion and entering the embryonic body. Schemas indicate a dorsal view of amnion-forming embryos. Red arrows indicate direction of the ventrad movement to close the pericardial cavity; blue arrows indicate direction of the dorsad movement to close the amnion. Asterisks in (d,e) indicate the edge of the pericardial fold. aip, anterior intestinal portal; am, amnion; amu, amniotic umbilicus; fl, forelimb; hl, hindlimb; ht, heart tube; opv, optic vesicle; otv, otic vesicle; sac, sero-amniotic connection.
