ORTMANN : TERTIARY INVERTEBRATES. 215 



Affinities: This is the first true Murex known from the Patagonian 

 beds, and, indeed, the first that is referable without doubt to this genus 

 from any South American Tertiary deposits, and it belongs in the sub- 

 genus Phyllonotus Montf. Species of this type are hardly found before 

 Miocene times, but are quite abundant in Miocene, Pliocene, and Recent 

 beds. I cannot compare it with any known form, none having a particu- 

 larly close affinity to it, but on the whole it has a Neogene character. 



Gen. TROPHON Montf. 

 145. TROPHON PATAGONICUS (Sowerby). 



PI. XXXIV, Fig. 7"-". 



1846 Fusus patagoniciis Sowerby, in: Darwin, Geol. Observ. S. Amer., 



p. 259, pi. 4, f. 60. 

 1897 Trophon lac^niat^^s var. santacruzensis v. Ihering, in: Rev. Mus. 



Paul., v. 2, p. 294, pi. 3, f. 4. 

 1897 T. patag. v. Ihering, ibid., p. 296. 



1899 T. p. v. Ihering, in: N. Jahrb. Miner., etc., v. 2, p. 31. 



1900 T. p. Ortmann, in: Amer. Journ. Sci., v. 10, p. 380. 



Shell ovato-oblong, with lamelliform varices. Whorls angulated, upper 

 part, near the suture, flat, varices not extending upon this flat part, or 

 only represented by growth-lines. Number of varices from 8 16, on the 

 last whorl sometimes quite crowded, on the upper whorls more or less 

 distant, elevated, and produced, on the angulation, into acuminate, often 

 recurved lobes. Mouth subcircular or subovate, canal about as long as 

 the mouth or a little shorter, umbilicus larger or smaller. Whole surface 

 of shell, except upper flat part, with spiral striae, which are more or less 

 distinct, often entirely obliterated. 



Measurements (not quite complete individual) : Height, 72 mm, diame- 

 ter (varices included) 60 mm ; another one, with the upper end gone : 

 Height, 82 mm, diameter, 75 mm ; of a complete individual : Height, 63 

 mm, diameter, 38 mm. 



Remarks: v. Ihering's T. laciniatus var. santacruzensis differs, at the 

 first glance, considerably from Sowerby's T. patagonicus: nevertheless, 

 both are connected by numerous intermediate forms, so that it is impos- 



