The largesizeandrapiddevelopmentofamphibianembryoshasfacilitatedground-breakingdiscoveries
in developmentalbiology.Here,wedescribetheembryogenesisoftheBudgett'sfrog(Lepidobatrachus
laevis), anunusualspecieswitheggsthatareovertwicethediameteroflaboratory Xenopus, andembryos
that cantoleratehighertemperaturestodevelopintoatadpolefourtimesmorerapidly