Ligation of developing embryos of Drosophila melanogaster was performed at three different stages of nuclear multiplication and at the cellular blastoderm stage. Egg fragments of variable sizes are able to continue development up to the hatching stage. Partial embryos differentiate larval structures, anterior fragments forming larval head and posterior fragments larval abdominal structures. These fragments differentiate a variable number of the twelve larval cuticular bands formed by intact embryos. We found that ligation at cellular blastoderm can lead to anterior and posterior fragments which differentiate together all the twelve bands, indicating that at this stage the embryo develops these patterns in a mosaic fashion. Ligation of younger embryos prevents the differentiation of some intermediate larval cuticular bands, while the terminal ones are consistently differentiated. The number and position of the deleted bands is correlated with the time and position of ligation. This indicates that the mosaic pattern present in the egg at blastoderm is not fully formed at earlier stages in development.