ORTMANN I TERTIARY INVERTEBRATES. 21J 



Record of specimens : Mouth of Santa Cruz River, 13 sp.; San Julian, 

 Oven Point, 21 sp.; San Julian, Darwin Station, 5 sp.; 30 miles north of 

 upper Rio Chalia, i sp.; Lake Pueyrredon, base of Tertiary, 4 sp.; Lake 

 Pueyrredon, 600' above base, I sp. 



Distribution: San Julian (Sow., see Darwin, 1846, p. 112); Santa Cruz, 

 La Cueva, and Jegua quemada, Patagonian beds (v. Ih.). 



Affinities: This species is apparently the ancestral form of both, T. 

 laciniatus, which is found in the Cape Fairweather beds, and is also 

 recent, and T. geversianus, which is recent. 



The genus Trophon, according to Zittel (1885, p. 278) is a character- 

 istic Tertiary genus, and hardly found before Oligocene times. The 

 present species has no closely allied forms in deposits of the northern 

 hemisphere. 



146. TROPHON LACINIATUS Martyn. 



PI. XXXIV, Fig. 8-". 



1847 Fusus /. Reeve, Conch. Icon., v. 4, pi. 4, f. 14. 



1878 Trophon I. Kuester & Kobelt, in : Martini & Chemnitz, System. 



Conch.-Cabin., v. 3, pars 2, p. 280, pi. 72, f. 6, 7. 

 1880 T. /. Tryon, Man. Conch., v. 2, p. 143, pi. 31, f. 330. 

 1897 T, 1. Pilsbry, in : Pr. Acad. Philad., p. 329. 



Shell ovato-oblong, with lamelliform varices ; whorls more or less 

 angulated, upper part, near the suture, flat, narrow, crossed by the varices. 

 Varices quite numerous, elevated into ear-like lobes on the angulation. 

 Mouth suboval, canal moderately long, umbilicus larger or smaller. 

 Surface of shell, between the varices, without spiral sculpture. 



Height (not quite complete), 62 mm, diameter, 36 (varices 'included) ; 

 height (not quite complete), 72 mm, diameter, 38 mm. 



Remarks : The ear-like lobes in this Cape Fairweather fossil are larger, 

 but less acuminate than in the recent form, but I do not think that this 

 warrants the creation of a new species, especially if we take into consid- 

 eration the enormous variability of the recent form. 



Record of specimens : Cape Fairweather, 16 sp. 



Distribution: Known living from the Straits of Magellan and Pata- 

 gonia. 



