Abstract
Thirteen enzymatic systems have been explored using electrophoretic techniques in eighteen permanentin vitro lines or clones ofDrosophila melanogaster embryonic cells. Significant differences have been observed and the isozymic patterns seem to constitute reliable markers for the characterization of the different lines. Moreover, interesting comparisons are possible with the data previously collected by several groups on the tissue-specific or stage-specific isozymic patterns inDrosophila. This study may give us some clues about the functional differentiation, underin vitro conditions, of the established lines ofDrosophila cells, and perhaps furnish some information on their tissue origin.