Scanning electron microscope image of Strongylocentrotus drobachiensus [sea urchin] gastrula. This is a higher magnification image of CIL39765. The embryo was split open to reveal a nice cross-section
N = sample size. Lm, labrum; Lb-sg1, first segment of labium; Lb-sg2, second segment of labium; Lb-sg3, third segment of labium; Lb-sg4, fourth segment of labium; Lb-sg5, fifth segment of labium; Md,
