2O2 PATAGONIAN EXPEDITIONS I PALAEONTOLOGY. 



or subacute nodes. In the upper part of the whorls, in the region of the 

 nodes, the spiral ribs (8 to 10 of them) are fine and subequal ; in the lower 

 part, below the nodes, are, on the last whorl, 5 to 6 stronger ribs, alter- 

 nating with finer ones, followed by about 5 finer ones in the lowermost 

 part of this whorl. 



Height of largest complete individual : 56 mm, diameter, 35 mm ; a 

 fragment has a diameter of 40 mm. 



Remarks: V. Ihering does not mention the finer ribs on the lowermost 

 part of the last whorl, which are not shown in casts. Well-preserved 

 specimens of medium size agree completely with Philippi's figure of 5". 

 chilensis, having the nodes more conical and subacute, and thus I was led 

 to believe that S. ameghinoi and chilensis are identical. But v. Ihering 

 writes to me, that the true 5. chilensis has 19 very fine spiral threads in 

 the region of the nodes. If that is the case, it is impossible to unite 

 these two species. 



Record of specimens: Mouth of Santa Cruz River, 43 sp.; San Julian, 

 Oven Point, i sp.; 30 miles north of Upper Rio Chalia, 4 sp.; Lake 

 Pueyrredon, base of Tertiary, 5 sp.; Lake Pueyrredon, 600' above base, i sp. 



Distribution: La Cueva and Santa Cruz, Suprapatagonian and Pata- 

 gonian beds (v. Ih.). In 1899 (p. 37) v. Ihering doubts the occurrence of 

 this species in the "Patagonian" beds. 



Affinities: S. chilensis Phil, is the representative of this species in the 

 Navidad beds of Chili (Matanzas and Navidad). 



i32a. STRUTHIOLARIA AMEGHINOI VAR. MULTINODOSA var. nov. 



PL XXXIII, Fig. ii 6 . 



Not so high, more globular. Whorls convex, hardly angulated, nodes 

 18-19, more elongated and distinctly costiform. Only 4 to 5 stronger 

 ribs on the lower part of the last whorl, without intermediate finer ones, 

 followed by about 5 finer ribs on the lowermost part of this whorl. 



Height, 32 mm, diameter, 21 mm; another: height, 41 mm, diam- 

 eter, 27 mm. 



Remarks: I first believed that this was v. Ihering's S. ornata var. dense- 

 striata (1897, P- 2 9 r > textfig. 15) ; but after having sent a specimen to v. 

 Ihering he informs me that it is not his S. densestriata, the latter being 

 merely a S. ornata without the two larger spiral ribs. 



