NF stage 4 (8-cell)

^ http://purl.obolibrary.org/obo/XAO_1000014

Nieuwkoop and Faber stage 4, corresponding to an embryo of age 2 hr 15 min at 22-24 Celsius and having the following external morphological criteria: Advanced eight cell stage. Dorsal micro- and macromeres usually smaller than ventral ones; dorsal micromeres less pigmented than ventral ones. Length: 1.4 - 1.5 mm. [ https://www.worldcat.org/search?q=bn%3A0815318960 ]

Synonyms: 8-cell stage