246 PATAGONIAN EXPEDITIONS I PAL/EONTOLOGY. 



Distribution : Navidad, Matanzas, Tubul and Lebu, associated with 

 Pyrula hombroniana, said to be from the Navidad beds (Phil.). Re- 

 corded also from the Cretaceous of Tumbez. Moericke (1896, p. 394) 

 questions this fact. 



Affinities : Among the numerous Tertiary species of Btilla, it is hard 

 to point out a particular one to which this one shows the closest affinities. 

 It seems to me that B. striatissima Deshayes (1864, p. 636, pi. 38, f. 

 20-22), from the Eocene of the Paris basin might be compared with B. 

 remondi, although the form of B. striatissima is slightly shorter, the mouth 

 a little more produced upward and the spiral sculpture much finer. An- 

 other species that might be compared is B. conoidea (Deshayes, p. 622, 

 pi. 39, f. 24-26), from the Oligocene of Europe, but the latter is a little 

 more inflated and less cylindrical and the apex is less distinctly excavated. 



173. BULLA PATAGONICA V. Ihering. 

 PI. XXXVII, Fig. 8-'. 



1897 B. p. v. Ihering, in: Rev. Mus. Paul., v. 2, p. 271, textfig. 8. 



Shell subcylindrical, a little narrowed above. Apex deeply umbilicated, 

 funnel-shaped with a blunt edge ; whorls hidden. Surface with spiral 

 striae in the lower part of the shell ; the striae are wanting in the upper 

 part. Mouth elongate, narrow above, very slightly produced upward, di- 

 lated below the middle. No fold on the columella. 



Height, 12 mm, diameter, 6 mm; another one: Height 10 mm, di- 

 ameter, 4.5 mm. V. Ihering gives : Height, 1 1 mm, diameter, 5.5 mm. 



Remarks : This species is closely allied to the preceding in general 

 form, although it seems to be a little shorter (rel. of H. : D. = 2 : i or 

 2.2:1). The chief difference is the development of the spiral lines, 

 which are distinct only in the lower half or one-third of the last whorl. 

 In most individuals there is no trace of the spiral lines in the upper part, 

 but in some of them, especially young ones, there is a slight indication of 

 these lines, but they are always much less distinct than in the lower part. 



Sometimes there are a few of these lines (1-3), more distinct from one 

 another, near the upper extremity. The striae (impressed lines) are more 

 remote from one another than in B. remondi. 



Record of specimens: Mouth of Santa Cruz River, 109 sp; Arroyo Gio, 

 2 casts. 



