Hα emission (from GOLDMine) of NGC 4189 (top row) and NGC 4298 (bottom row) with overplotted ¹²CO(1–0) (left column), 250 μm emission (middle column), and HI surface mass density (right column). The contours of ¹²CO(1–0) line are 4.2, 6.9, 9.6, 12.3, 15, and 17.7 M_⊙ pc^-2 for NGC 4189 and 0.5, 8.8, 17.1, 25.4, 33.7, 42, and 50.3 M_⊙ pc^-2 for NGC 4298. The 250 μm contours are at 0.23, 0.28, 0.31, 0.36, 0.42, 0.48, 0.56, and 0.65 Jy beam^-1 for NGC 4189 and 0.2, 0.3, 0.41, 0.63, 0.84, and 1.06 Jy beam^-1 for NGC 4298. The HI surface mass density contours are at 4.8, 7.2, 10, 12.4, 14.8, and 17.2 M_⊙ pc^-2 for NGC 4189, and at 4.3, 5.2, 6, 7, 8, 9.1, 10.6 M_⊙ pc^-2 for NGC 4298. The beam size of each observations is shown in the bottom left of each panel.