Expression of the wingless gene in the embryo of the millipede Glomeris marginata. Shown is the localisation of wingless transcripts via in situ hybridisation. The ventral wingless expression is located just anterior to the position of the engrailed stripe (see Fig 6). Dorsally, no wingless transcripts are detected. The asterisks mark the dorsal metameric units, which are the lateral plates of Dohle . The location of the future ventral (v) and dorsal (d) tissue is marked, see also figure 6. (A and B): embryo at stage 4, (C and D): embryo at stage 4.1 (staging see [4,6]). Panel A and C show the bright field micrograph of the in situ hybridisation staining; panel B and D show the epifluorescence image of the embryo in A and C, respectively, in which the nuclear DAPI staining becomes bright, and the in situ hybridisation staining appears dark due to quenching of the fluorescence. Abbreviations: d: dorsal; v: ventral; lb: labrum; an: antennal segment; pmd: pre-mandibular segment; md: mandibular segment; mx: maxillary segment; p: post-maxillary segment; 1–6: ventral leg bearing segment 1–6, s: stomadeum.