ORTMANN : TERTIARY INVERTEBRATES. 
201 
Fam. S TR OMB ID RE d’Orb. 
Gen. STRUTHIOLARIA Lmck. 
1 3 1 . Struthiolaria hatcheri Ortmann. 
PL XXXIII, Fig. io a - 6 . 
1899 S. h. Ortmann, in: Amer. Journ. Sci., v. 8, p. 431. 
Shell ovato-pyramidal, spire scalariform. Whorls with revolving ribs, 
which number 20 to 22 on the last whorl, and are all equal in size and 
distance from each other. Upper part of the whorls oblique, not canalic- 
ulate, rendered subangular by a series of 10-11 blunt, conical, subcosti- 
form nodes. Of the spiral ribs, about 5 or 6 are in the region of the 
nodes, the rest (14-15) are below the nodes, on the lower part of the 
whorls. 
Measurements: Height, 22 mm, diameter, 13 mm; another: height, 
21 mm, diameter, 14 mm. But it grows a little larger, as is shown by 
a fragment that is 16 mm in diameter. 
Remarks : This species differs from all the other South American spe- 
cies of the genus in the spiral ribs, which are of uniform size, in the upper 
part as well as in the lower part of the whorls. In all the following spe- 
cies there are at least a few ribs on the lower part of the last whorl, 
which are distinctly and considerably stronger than those on the upper 
part. Also the small number of nodes, and the suture, which is not 
canaliculate, serve to distinguish this species. 
Record of specimens : Punta Arenas, horizon II (lower Magellanian), 8 sp. 
132. Struthiolaria ameghinoi v. Ihering. 
PI. XXXIII, Fig. ii°. 
1897 S. ameghinoi v. Ihering, in: Rev. Mus. Paul, v. 2, p. 289, textf. 14. 
1900 S. chilensis Ortmann, in: Amer. Journ. Sci., v. 10, p. 380 (non S. 
chilensis Phil., 1887). 
Shell ovato-pyramidal, spire scalariform. Whorls spirally ribbed, on the 
last whorl about 20 to 25 ribs, which are very unequal. Upper part of 
whorls oblique near the suture, not canaliculated, angulated, angulation 
formed by a series of 12 to 16, rarely up to 18, costiform, conical, blunt 
