Toucasia carinata orientalis Nagao
1932. Toucasia carinata var. orientalis Nagao, p. 511, text-figs.-1933b. Toucasia carinata var. orientalis Nagao: Nagao, p. 164, pl. 21, figs. 1, 2, pl. 22, figs. 1-5.-1964. Toucasia carinata orientalis Nagao: Saito, p. 320, pl, 47, figs. 8, 9.
Type. —Syntype (GMH nos. 5707, 5776, 5779, 5781, 5782, 5784) from the lower course of the Sorachi, between Ponmoshiri and Shimanoshita, Ishikari Prov., Hokkaido.
Age and distribution. —Aptian. Lower Yezo group ("Orbitolina limestone") in Sorachi area.

Praecaprotina yaegashii (Yehara) [Pl. 10, Fig. 11]
1920. Horiopleura Yaegashii Yehara, p. 41, pl. 1, figs. 1-3, pl. 2, figs. 1-3.-1926. Praecaprotina yaegashii (Yehara): Yabe and Nagao, p. 21, pl. 7, figs. 1-10.-1934. Praecaprotina yaegashii (Yehara): Nagao, p. 226.-1964. Praecaprotina yaegashii (Yehara): Saito, p. 320, pl. 47, figs. 10-12.
Type. —Syntype (IGPS not registered) from Moshi, Iwaizumi, and Hiraiga, Tanohata, Iwate Pref.
Age and distribution. —Aptian. Miyako group (Tanohata and Hiraiga formations) in Omoto and Tanohata areas.

Explanation of Plate 10 Fig. 1. Izumicardia parva Ichikawa and Maeda: type-species of genus Izumicardia. Holotype (OCU MM286), rubber cast from right external mould, × 2. Loc. Mikumayama, Sumoto (Campanian, Izumi group). Reproduced from Ichikawa and Maeda, 1963, pl. 9, fig. Id. Fig. 2. The same species. Topotype (OCU MM291), rubber cast from right internal mould, × 2. Loc. ditto. Reproduced from Ichikawa and Maeda, 1963, pl. 9, fig. 7a. Fig. 3. Clisocolus (Crenocolus) crenulatus Ichikawa and Maeda: type-species of subgenus Crenocolus. Holotype (OMM F1025), right valve, ×1. Loc. Azenotani, Izumi mountains (Campanian, Izumi group). Reproduced from Ichikawa and Maeda, 1966, pl. 7, figs. 1a-c. 3a: external view, 3b: internal view, 3c: upper view. Fig. 4. Izumia trapezoidalis Ichikawa and Maeda; type-species of genus Izumia, Topotype (OCU MM276), clay cast from left internal mould, × 3. Loc. Mikumayama, Sumoto (Campanian, Izumi group). Reproduced from Ichikawa and Maeda, 1963, pl. 10, fig. 8b. Fig. 5. The same species. Holotype (OCU MM262), right internal mould, × 2. Loc. ditto. Reproduced from Ichikawa and Maeda, 1963, pl. 10, fig. 1a. × Fig. 6. The same species. Topotype (OCU MM337), clay cast from right internal mould, × 3. Loc. ditto. Reproduced from Ichikawa and Maeda, 1963, pl. 10, fig. 7b. Fig. 7. Eoursivivas matsumotoi (Hase): type-species of genus Eoursivivas. Right internal mould (GF K63050), × 2. Loc. Sakayori-agaru, Yatsushiro (Neocomian, Kawaguchi formation). Reproduced from Ota, 1964, pl. 21, fig. 1. Fig. 8. The same species. Left internal mould (GF K63061), ×1.8. Loc. ditto. Reproduced from Ota, 1964, pl. 21, fig. 3. Fig. 9. Pulsidis nagatoensis Ota: type-species of genus Pulsidis, Holotype (GF Y6301), right internal mould, × 2.5. Loc. Yoshimo, Shimonoseki (Neocomian, Yoshimo formation). Fig. 10. Nipponicorbula mifunensis Ota: type-species of genus Nipponicorbula. Paratype (GF M63002), right valve, × 3. Loc. Asanoyabu, Kamimasuki (Cenomanian or Turonian, Mifune group). Reproduced from Ota, 1964, pl. 21, fig. 19. Fig. 11. Praecaprotina yaegashii (Yehara): type-species of genus Praecaprotina. Syntype (IGPS not registered), bivalved specimen, ×1. Loc. Moshi, Iwaizumi (Aptian, Miyako group). Reproduced from Yabe and Nagao, 1926, pl. 7, fig. 1.

Pachytraga japonica Okubo and Matsushima
1959. Pachytraga japonica Okubo and Matsushima, p. 2, text-figs. 1-7.
Type. —Holotype (Dept. of Geology, Shinshu Univ., not registered) from Toyama, Nagano Pref.
Age and distribution. —Lower Cretaceous (precisely unknown). "Shimantogawa group" of Shirane belt in Shirane area.

Caprina uwajimensis Shikama and Tanabe
1970. Caprina uwajimensis Shikama and Tanabe, p. 53, pl. 6, fig. 1, pl. 7, figs. 1, 2.
Type. —Holotype (GYU M-17) from Mt Kushima island, Uwajima, Ehime Pref.
Age and distribution. —Santonian. Uwajima group (Makinoyama formation) in Uwajima area.