FIGURE 14. Mellopegma indecorum (Missarzhevsky in Rozanov et al., 1969) from the early Cambrian of Siberia. 1-6, SMNH Mo167615, locality indicated as middle Lena River, but without number; possibly M303/2), same specimen as in Missarzhevsky (1989; Plate VI, fig. 11), but with other side shown here. 5-6, detailed views showing possible traces of laminar shell microstructure. Arrows show possible imprints of crystal tablets. 7-9, SMNH Mo167616, locality 183e. 10-12, SMNH Mo167617, locality 183e. 13-16, SMNH Mo167618, locality M303/2. 17-20, SMNH Mo167619, locality M303/2. Scale bars 1-4, 10-14, 17-20, 200 µm; 5-6, 5 µm; 7-9, 15-16, 100 µm.