ORTMANN : TERTIARY INVERTEBRATES. 91 



1860, p. 906, pi. 67, f. 22-25); it differs considerably from our species in 

 size, shape and sculpture, the latter consisting of fine, sharp and nodulose 

 ribs. C. aldrichi Dall (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, flattish, equal, but not 

 geminate ribs. In the sculpture of the shell, C. tceniata Dall (ibid., p. 631, 

 pi. 25, f. i), 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. dancim' 

 is intermediate in sculpture between the Eocene C. aldrichi, and the 

 Pliocene C. tceniata, approaching in form more the former. 



Fam. LIMOPSID^E Dall. 



Gen. LIMOPSIS Sassi. 

 29. LIMOPSIS INSOLITA (Sowerby). 



PI. XXV, Fig. 6. 



1846 Trigonoccelia 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. i. 

 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 ^- i ns - 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. Umbones 

 not much prominent. Area triangular, high, with a triangular depression 

 in the middle below the apex, bordered by sharp margins. Hinge 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, ho\v- 



