ABSTRACT
FMM, Fossa Magna Museum; TMNH, Togakushi Museum of Natural History; GM, Geological Museum; UMUT, University Museum, the University of Tokyo.
Linthia nipponica Yoshiwara, 1899 (Figs. 1.1-1.4) Material. 39 specimens: TUM No. 5188, 8112, and 78350, UMUT CE18683-90, one specimen from TMNH, eight specimens from Kanazawa University, and 12 specimens collected in this study. All these specimens were used for biometric analysis. Description (see also Yoshiwara 1899, Nisiyama 1968). Tests range from 33 mm to 74 mm in length and from 16 mm to 35 mm in height. Test widths are almost as large as test lengths. The test is rounded-cordiform and gently arched aborally. Posterior extremity of the test is truncated vertically. The widest portion is located approximately at the middle of test length and the tallest point is subcenral, immediately behind the apical disc. The frontal notch is distinct but shallow and about 17 mm wide and 1.5 mm deep for a specimen with 62 mm test length (Figs. 1.1-1.4.).
