Indusium: the case made by an insect larva: a membranous layer of the embryo of Locustidae below the serosa.
serosa: the outer membrane that envelops the forming embryo, the amnion and the remainder of the egg.
Ventral plate: a thickening of the blastoderm of an egg from which the embryo, but not the amnion or serosa is formed.
serosa se·ro·sa (sĭ-rō'sə, -zə)
n. pl. se·ro·sas or se·ro·sae (-sē, -zē)
See serous membrane.
The chorion of a bird or reptile embryo.