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		After fixing and staining all samples with fluorescent 5C7 at the two-day old stage, the archenterons and vegetal plates could only be observed in control embryos. The other samples showed no archenteron or vegetal plates staining. Several small clumps of fluorescent staining could be observed, however they were free floating and not located where the archenteron or vegetal plate should be. Figure 3. A. Control Lytechinus variegatus at 5 days after fertilization. B. Fluorescent staining of control embryo from image A. The archenteron and vegetal plate are both visible. C. L. variegatus embryo from sample 2, which was UV irradiated just prior to fertilization. D. Fluorescent staining of same embryo from image C. No archenteron or vegetal plate visible. E. L. variegatus embryo from sample 3, which was UV irradiated 10 minutes post-fertilization. F. Fluorescent staining of same embryo from image E. No archenteron or vegetal plate visible. G. L. variegatus embryo from sample 4, which was UV irradiated 30 minutes post-fertilization. H. Fluorescent staining of same embryo from image G. No archenteron or vegetal plate visible.