(A-D) Nuclei in the region of one gonad arm were visualized by fluorescence microscopy of DAPI-stained animals. Examples are shown of (A) wild type, (B) fhod-1(tm2363), (C) exc-6(gk386), and (D) fhod-1(tm2363);exc-6(gk386) animals. For all strains, abundant nuclei of immature germ cells populate the distal gonad arms (blue), condensed chromosomes are visible in oocyte nuclei (white arrows) in the proximal gonad arms (pink), and punctate sperm nuclei (white arrowheads) are present in the spermathecae (green) adjacent to the uterus (yellow). Unique for the double mutants, large DAPI-stained masses that are present in the proximal gonad or the uterus (red arrows) are likely the nuclei of endomitotic oocytes. Scale bars, 50 μm.