ORTMANN : TERTIARY INVERTEBRATES. 
91 
i860, p. 906, pi. 67, f. 22-25); ^ differs considerably from our species in 
size, shape and sculpture, the latter consisting of fine, sharp and nodulose 
ribs. C. aldrichi Dali (1898, p. 630, pi. 32, f. 19), from the Eocene of 
Alabama approaches our species more closely in size and shape and also 
in sculpture, which consists, in C. aldrichi, of fine, flatfish, equal, but not 
geminate ribs. In the sculpture of the shell, C. tceniata Dali (ibid., p. 631, 
pi. 25, f. 1), from the Pliocene of Florida and Carolina, is still more closely 
allied to our form, showing geminate, and even quadripartite ribs ; the 
shape, however, of C. tceniata is different. Thus, it seems that C. darwini 
is intermediate in sculpture between the Eocene C. aldrichi , and the 
Pliocene C. tceniata , approaching in form more the former. 
Fam. LIM OPS I DEE Dali. 
Gen. LIMOPSIS Sassi. 
29. Limopsis insolita (Sowerby). 
PI. XXV, Fig. 6. 
1846 Trigonocoelia ins. Sowerby, in: Darwin, Geol. Observ. S. Amer., p. 
252, pi. 2, f. 20, 21. 
1864 Limopsis ins. Zittel, in: Novara Exp., p. 48, pi. 13, f. 1. 
1873 L. i. Hutton, Cat. Tert. Moll. Ech., New Zealand, p. 28. 
1886 L. i. Tate, in: Tr. R. Soc., South Australia, vol. 8, p. 134. 
1887 L. araucana Philippi, Tert. Quart. Verst. Chiles, p. 191, pi. 46, f. 4 (juv.). 
1897 L. ins. v. Ihering, in: Rev. Mus. Paul., vol. 2, p. 234. 
1899 L. i. v. Ihering, in: N. Jahrb. Min. Geol. Pal., vol. 2, p. 14. 
Shell suboval, very oblique, thick, convex. External surface, in well 
preserved specimens, with very fine radiating striae (fine grooves separated 
by flat intervals), and with distinct concentric lines of growth. Lhnbones 
not much prominent. Area triangular, high, with a triangular depression 
in the middle below the apex, bordered by sharp margins. Flinge teeth 
forming a curved line, anterior and posterior ones larger, median ones 
smaller. 
Height, 26 mm ; length, 25 mm. 
Remarks: The external surface of the shell is finely striated, a char- 
acter in which L. araucana is said to differ. Sowerby and Zittel, how- 
