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| Eggs 
      are obtained from hormone-stimulated female Xenopus laevis and fertilized in vitro following established lab procedures. Fertilized eggs are dejellied using 2% cysteine (pH 8.0) and reared at room temperature in 10% Holtfreter's solution. Larvae are staged according to the normal table of Nieuwkoop & Faber (1967). In Xenopus 
        laevis, cranial neural crest migration begins in the late neurula (stage 
        19).   Embryos are 
        placed in Petri dishes lined with 2% agar and   Small segments 
        of the cranial neural folds from host embryos are ablated   Care must be taken to remove the overlaying ectoderm. Grafts is held 
        in place initially with modeling clay and   Specimens can be viewed using a stereo dissecting microscope equipped with epifluorescence optics. | 
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