ORTMANN : TERTIARY INVERTEBRATES. 243 



Height, 19 mm; diameter, ca. 9 mm (apex gone). Height, 17 mm; 

 diameter, ca. 9 mm (larger part of apex gone). 



Remarks: The spiral sculpture is in most of our specimens quite indis- 

 tinct, worn off, only in one of them, a small one, it is well preserved. It 

 consists of a number of spiral cords, which, toward the canal, become finer. 

 The upper plait of the columella is stronger and longer than the lower 

 one, the latter being in one case so indistinct as to be hardly perceptible. 



Record of specimens : Mouth of the Santa Cruz River, 4 sp. 



Affinities: The genus Borsonia is quite characteristic of Eocene 

 deposits, being very rare in the Neogene. Our species agrees in shape, 

 size, and sculpture very closely with the European Oligocene species : B. 

 dehicii Nyst (see Speyer, 1867, p. 205, pi. 23, f. 34). This agreement is 

 so close that it is hard to point out a difference ; but it seems that the 

 spiral sculpture in B. dehicii is a little different, the cords being finer, 

 with smaller ones intercalated. Among the Eocene species of the Paris 

 basin, there is none that comes so near our species, although the differ- 

 ences between the species are not very marked. 



Fam. ACTA^ONIDAI d'Orb. 



Gen. ACTION Montf. 

 170. ACT/EON CHILENSIS Philippi. 



PI. XXXVII, Fig. 5 ' 6 . 



1887 A. c. Philippi, Tert. & Quart. Verst. Chiles, p. in, pi. 13, f. 16. 

 1899 A. c. Ortmann, in: Amer. Jour. Sci., v. 8, p. 431. 



Shell ovate, rather broad ; spire short, conical, about y^ of the length 

 of the shell ; whorls 5^ , convex, the upper ones much broader than high 

 (3 to 4 times as broad as high) ; suture distinct. Whole surface covered 

 with fine spiral furrows, which are punctate, subequal, and separated by 

 broad, flat intervals, crossed by extremely fine lines of growth. Mouth 

 elongate-ovate, columella with a fold below. 



Height, 8.5 mm; diameter, 5 mm; Philippi gives: Height, 10 mm; 

 diameter, 6.5 mm. 



Remarks: Philippi's enlarged figure appears more swollen than the 

 outline sketch in natural size ; the latter corresponds completely to our 



