32 PATAGONIAN EXPEDITIONS : PALEONTOLOGY. 



LUNATIA PUEYRRYDONENSIS. 

 PI. VI, Fig. 12. 



Shell of moderate size, broadly subovate, consisting of about four rap- 

 idly increasing convex whorls ; suture impressed, bordered by a narrow, 

 flattened shoulder; aperture subovate, narrow above, broadly rounded 

 below; callus of the inner lip rather narrow and thin, slightly reflected 

 over the narrow umbilicus below ; surface marked by numerous distinct, 

 crowded lines of growth. 



Height, 33 mm.; greatest breadth, 34 mm.; height of aperture, 28 mm.; 

 breadth of same, 1 8 mm. 



This species is easily distinguished from the preceding by its stouter 

 form, shouldered whorls and different sculpture. 



It is possible that these two species may prove to be synonyms of 

 European forms, but in the absence of actual specimens for comparison I 

 consider it safer to treat them as distinct species, rather than to attempt 

 to identify such simple forms by descriptions and figures only, especially 

 when the associated faunas are different. 



Locality and position. Represented by a single specimen from the 

 Ammonite (Belgrano) beds at mouth of canon four miles east of Lake 

 Pueyrrydon. 



APORRHAIS PROTUBERATUS sp. nov. 



PL VI, Figs. 13-15. 



Shell of medium size, rather stout, consisting of six or seven convex 

 whorls, of which the last on approaching the aperture becomes carinate 

 above the middle and flattened below, the carina extending in a curve to 

 the upper extremity of the wing ; aperture rather narrow and elongate ; 

 outer lip prolonged upward beyond the preceding whorl and produced in 

 a broad, very thick, subquadrate wing, whose outer margin is broadly 

 rounded below and extended above in a short blunt process ; inner lip 

 with a heavy callus that forms a subspherical protuberance just above the 

 anterior canal and extends in a thinner deposit over a large part of the 

 spire ; anterior canal short, broad and nearly straight, with a slight notch 

 or emargination at the extremity ; posterior canal not distinctly developed, 

 but apparently represented by the callus extending up the spire ; surface 



