Cirino et al.:   Laboratory culture of Ciona

Figure 7. Early embryonic stages of C. intestinalis. The characteristic outer follicle cells rest on the egg membrane, making it float (A). The first cleavage occurs within 1 h (B, C) . The next cell divisions take place every 20-30 min on average (4-cell stages in D). Scale, 200 µm. See the timetable of development in Fig. 19.