FIGURE 1. Locality maps and a stratigraphic section at the locality. 2, restoration of the Kawachi Bay following Osaka City Cultural Properties Association (2008). 3, the columnar section at OMNH-QV4816 locality, which was modified from a boring survey report in 1965.

FIGURE 2. Skull, OMNH-QV4816 in dorsal view. 1, Restoration of the skull based on a photo, which was taken just before specimen was damaged by pulling up from the locality. 2, Line art was made from the photo. The outline of the skull is anteroposteriorly extended at the level of the antorbital process (arrow), result of a slide between the lose frontal and maxilla.

FIGURE 3. Maxilla, premaxilla and vomer, OMNH-QV4816. 1, left anterior part of maxilla and premaxilla. 2, left middle part of maxilla. 3, left preorbital region of maxilla. 4, right anterior part of maxilla. 5, right preorbital region of maxilla. 1-5, in dorsal view. 6, right anterior part of maxilla. 7, right preorbital region of maxilla. 8, left anterior part of maxilla and premaxilla. 9, left middle part of maxilla. 10, left preorbital region of maxilla. 6-10, in ventral view. 11 to 13, vomer. 11, in dorsal view. 12, in left lateral view. 13, in posterior view.

FIGURE 4. Frontals, OMNH-QV4816. 1, left in dorsal view. 2 and 3, right in dorsal view. 2, line art. 3, photo. 4 and 5, right in ventral view. 4, photo. 5, line art. 6. right in ventral view. 7 and 8, in right lateral view. 7, photo. 8, line art.

FIGURE 5. Posterior part of skull, OMNH-QV4816 in dorsal view. Top, photo. Bottom, line art.

FIGURE 6. Posterior part of skull, OMNH-QV4816 in ventral view. Top, photo. Bottom, line art.

FIGURE 7. Posterior part of skull, OMNH-QV4816 in anterior view. Top, photo. Bottom, line art.

FIGURE 8. Posterior part of skull, OMNH-QV4816 in posterior view. Top, photo. Bottom, line art.

FIGURE 9. Posterior part of skull, OMNH-QV4816 in right lateral view. Top, photo. Bottom, line art.

FIGURE 10. Map showing records of Balaenoptera edeni and B. brydei. 1, around Japan. 2, in the Seto Inland Sea including the Osaka Bay. See Table 2.