ORTMANN I TERTIARY INVERTEBRATES. 199 



1885 V. i. Zittel, Handb. Palaeont, v. 2, p. 212, textf. 285. 

 1900 V. cf. i. Ortmann, in: Amer. Journ. Sci., v. 10, p. 379. 



Shell generally gregarious, tubular, subquadrate, closely and regularly 

 spiral in the young state, with the whorls in close contact. The extrem- 

 ity suddenly reflected, straightened and free. Aperture subcircular. 

 Surface transversely rugose and often with longitudinal ribs. 



Diameter of tubes in our specimens : 2 mm. 



Remarks: Our specimens are not well preserved and only fragmentary, 

 but they agree in general form closely with the figure given by Hoernes. 

 Longitudinal ribs are present at the suture, where the whorls touch each 

 other, and further, there seems to be a single rib in the middle of the 

 whorls, but this rib is visible only on the uppermost whorl of the figured 

 specimen. In size (diameter), our specimens agree best with Wood's 

 figure 8a, and differ considerably from that of the Italian Pliocene form 

 figured by Zittel. 



Record of specimens : Shell Gap, Rio Chico, upper horizon : i sp.; Lake 

 Pueyrredon, 600' above base : i sp. 



Distribution: V. intortus is found in Oligocene, Miocene, and Pliocene 

 deposits of Europe. 



Affinities: Our specimens agree best in the surface characters with the 

 Central-European Miocene form figured by Hoernes, in size with the 

 English Pliocene form figured by Wood, while the Italian Pliocene form 

 is larger, and has more, and more distinct longitudinal ribs. According 

 to Moerch's diagnoses, it would correspond best to the French Miocene 

 form of this species. There remains, however, some doubt, whether we 

 really have to deal here with this European species, but the material at 

 hand is too incomplete to decide this question. 



129. VERMETUS (?) INCERTUS sp. nov. 



PI. XXXII, Fig. 2. 



Tubes fragmentary, elongate-cylindrical, very slightly and irregularly 

 curved, almost straight. Walls thick. Outer surface transversely rugose, 

 in one specimen indistinctly flattened on one side. 



Diameter of tube : 58 mm. 



Remarks: There is considerable doubt whether these tubes belong at 

 all to Vermetus, and I cannot find any described species, with which to 



