ORTMANN : TERTIARY INVERTEBRATES. 197 



1897 T. Patag. v..Ihering, in : Rev. Mus. Paul., v. 2, p. 287 (after Sowerby), 

 1899 T. patag. v. Ihering, in: N. Jahrb. Miner., etc., v. 2, p. 26. 



Shell elongated, forming an angle of about 17 to 24. Suture simple, 

 not in a furrow. Whorls flat, with a number of finer or stronger striae, 

 three of which are usually stronger and granulate. 



Height, 28 mm (not complete); diameter, u mm; height, 38 mm (not 

 complete); diameter, 14 mm. 



Remarks: This species resembles T. ambulacrum in its more rapidly 

 increasing whorls, but is distinguished at once by the lack of a sutural 

 depression. The three larger revolving ribs are less pronounced, and in 

 well preserved individuals they show distinct granulations, which are inde- 

 pendent of the lines of growth. 



There is no doubt that the form mentioned by v. Ihering in 1899 under 

 the name of T. patagonica agrees with our individuals ; but there is some 

 doubt whether it is really T. patagonica of Sowerby, since the figure 

 given by the latter shows a distinct sutural furrow. But in this respect 

 the figure does not correspond to Sowerby's diagnosis, which says: 

 "sutura indistincta." Perhaps as v. Ihering suggests this figure is 

 not accurate. 



I have not the slightest doubt that Philippi's T. darwini belongs here, 

 since diagnosis as well as figure correspond closely, with the exception 

 that granulations are not mentioned : but their apparent lack may be due 

 to fossilization, as is the case in most of our specimens. 



Young fragments are hard to distinguish from T. ambulacrum, since in 

 young ones of the latter species the suture is much less deep than in older 

 ones. 



Record of specimens : Mouth of Santa Cruz River, 6 sp. ; Paso del Rio 

 Santa Cruz, i sp. ; San Julian, Oven Point, 1 1 sp. ; 30 miles north of 

 upper Rio Chalia, 2 sp. 



Distribution: Port Desire (Sow.), Santa Cruz (Roch. & Mab., v. Ih.), 

 Navidad beds of Chili: Navidad (Sow., Phil.), Lota, Tubul, Lebu 

 (Phil.). 



Philippi erroneously says that Darwin found this species at Puerto del 

 Hambre (Port Famine). 



Affinities: T. chipolana Dall (1892, p. 312, pi. 22, f. 24), from the 

 Miocene of Florida seems to be closely allied in form and sculpture, but 

 the sculpture seems to be more complex and more strongly developed. 



