ABT. 8 SOUTH AMERICAN GASTROPODS — MARSHALL O 



CHILINA NEUQUENENSIS, new species 



Plate 1, Figure 5 



Shell rather thin, slender, very elongate, turreted. Spire one-half 

 the length of the whole shell, sharply acuminate. Whorls about 

 6.5 (nuclear whorl lost). Early portion of shell normal but a 

 marked ridge begins to develop upon the upper portion of the whorl, 

 which on the later whorls becomes almost a carina, forming a slop- 

 ing shoulder. Suture well marked, slightly crenulate. Axial sculp- 

 ture consisting of numerous, irregular growth riblets, with longer 

 rest periods more strongly marked. Spiral sculpture of two impressed 

 lines near the suture, several revolving riblets on the lower part 

 and faint indications of spiral striae. The crossings of the spiral 

 riblets by the axial sculpture give a malleated appearance to the 

 lower portion of the body whorl. Ground color olive-yellowish with 

 zigzag flashings of reddish on the upper whorls, two bands of arrow- 

 head markings of the same color, and three like-colored plain bands 

 on the body whorl. Aperture very long and narrow, its outer wall 

 perpendicular, outer lip broken off but evidentlj^^ simple. Columella 

 arcuate, rather broad, white, with a prominent entering oblique fold 

 near its middle portion. Parietal wall with a thin, white callus. 

 Color of interior pinkish overlaid with a thin deposit of white, the 

 exterior banding and arrow markings showing through. 



Type.—T\\Q type (U.S.N.M. No. 414168) measures: Length, 37 

 mm; diameter, 18 mm; length of aperture, about 18 mm. It was 

 collected in December, 1926, in " Las Lagunas," Province of Neuquen, 

 Argentina, by Senor JVIendez, of Santiago, Chile, and was presented 

 by D. S. Bullock, of Angol, Chile. As the Province of Neuquen is 

 on the east side of the Andes, this would be in the Atlantic drainage. 



When received, the specimen was completely encrusted, except the 

 aperture, with a thick deposit of iron, through which no hint of the 

 colors could be seen and which to a large degree concealed the form 

 of the shell. Oxalic acid quickly removed the iron, revealing a good 

 specimen except for the lost nucleus and broken outer lip. 



Remarks. — The nearest relative is CMlhia oldroydae Marshall, 

 which occurs in Lake Fetalafquen, Province of Chubut, not very far 

 south of Neuquen. C. oldroydae is a much larger, more inflated 

 shell than C. 7i£uquenemw. The former, as shown in figures with 

 the original description, varies from bulimoid form to a turreted 

 form on one side and to a nearly globose form on the other side. 

 The two species may have had a common ancestry, or G. neuquenen- 

 sis may be a subspecies of C. oldroydae or an extreme development 

 of the turreted form of the latter. In slenderness, O. nevquenensis 

 vies with C. ficeglensw E. A. Smith for first place, but in other 

 respects the two species are not closely related. 



