These thickened tracts of ectoderm in Peripatus and a few other forms can be clearly seen to surround the blastopore.
Ectoblast: the outer wall of a cell; the ectoderm or epiblast.
Farther up, within the velar area, the rudiments of the cerebral nerve-ganglion ng are seen separating from the ectoderm.
Metablastic: relating to the ecto- or meta-blast or ectoderm.
D, E, F, a thickening of the ectoderm on the distal side of the bud forms an entocodon (Gc).
The outer is the Ectoderm and the inner is the Endoderm or Hypoblast.
Amongst other structures which arise from the important layer of ectoderm are the teeth.
The medusoids have a muscular velum of ectoderm and mesogloea only.
The gonads, whether formed in the polyp or the medusa, are developed in the ectoderm.
It has been shown that these asulcar filaments are derived from the ectoderm, the remainder from the endoderm.
ectoderm 1861, from ecto- + derm.