ORTMANN I TERTIARY INVERTEBRATES. 185 



New Zealand : Pareora beds = Miocene (Zitt, Hutt). 



Affinities: The living C. fornicata L. (see Ball, 1889, pi. 50, f. 23, 24) 

 from the Atlantic coast of North America and the West Indies is very 

 closely allied, and its range in time begins in the Miocene. The Pata- 

 gonian fossil, however, is much larger, generally more elongate, more 

 solid and thicker, and especially the apical margin is more thickened. 



I cannot distinguish the Patagonian fossil from C. prcerupta Conrad 

 (1849, P- 7 2 7 pl- 1 9< f- 9. Io ) from the Miocene of Astoria, Oregon, which, 

 according to Gabb (1869, p. 81) is identical with C. princeps Conrad 

 (1856, p. 326, pl. 6, f. 52) from Subrecent beds of St. Barbara, California 

 (also living). And, further, Gabb identifies this species with Crypta gran- 

 dis Middendorf (1849, P- IOI pl- IZ f- 8-10) from Bering Sea. If all 

 these should really prove to be forms of one and the same species, the 

 range would be in the northern Pacific also from Miocene to Recent 

 times, and give to the Patagonian beds a distinctly Neogene age. 



1 1 6. CREPIDULA DILATATA Lamarck. 



Pl. XXXII, Fig. ii. 



1843 C. d. d'Orbigny, in: Voy. Amer. Merid., v. 5, p. 465, pl. 58, f. 6. 

 1859 C. d. Reeve, Conch. Icon., v. n, pl. i, f. 3. 



1886 C. d, Tryon (pro parte), Man. Conch., v. 8, p. 127, pl. 37, f. 

 3i 32- 



Shell rather thick, broadly ovate or irregularly circular, depressed ; sur- 

 face smooth except for growth-lines. Apex obliquely curved, marginal. 

 Diaphragm slightly concave, hardly reaching to the middle of the shell, 

 its margin sinuate. 



Measurements (of a cast) : Length, 20 mm; width, 18 mm; height, 

 6.5 mm. 



Remarks: This species differs at once from the foregoing in the broader 

 and almost circular outline. All our individuals are casts and compar- 

 atively small, and it seems that the shell was not as thick as that of C. 

 gregaria. Tryon (1. c., p. 127) unites with this species the C. grandis of 

 Middendorf (see above) from the North Pacific, but all the figures pub- 

 lished of the latter are more elongate, so that I believe it comes nearer 

 to C. gregaria. 



Record of specimens : Cape Fairweather ; 5 casts. 



