arch i blast (arkiblast)

[ IMG:content-1080.png:[blocks in formation] parablast. Wilhelm His. (b) A name given archiepiscopate (ärki-ē-pis'kō-pāt), n. [ arch i- blastulæ (-lē). [NL., άρχι- , chief, + NL. blastula .] In embryol ., a hollow and usually globular vesicle, the walls of which consist of a single layer of similar cells, and which by in- vagina tion develops an arch i gastrula. Yelk-division is complete and regular, and gives rise to a vesicular morula ( arch i blastula of Haeckel), each cell of which is provided with a flagellate cilium. Huxley, Anat. Invert., p. 553.