PILSBRY: non-marine MOLLUSCA of PATAGONIA. 527 



6.7, aperture 6.7 mm.; whorls 5. One from near the Sierra Ventana is 

 similar. 



In a pool near the Sierra Oveja the shells are similar, but darker colored, 

 more olive. The apices are eroded. 



Lymn/GA diaphana inelegans subsp. nov. 



(Plate XLVI, Figs, i, 2, 4-6). 



The shell is narrowly rimate, short and wide, the last whovl dispropor- 

 tionately large, inflated, with sculpture of rather coarse growth-wrinkles 

 and more or less malleation. The spire is small, shortly conic. Aper- 

 ture very ample. Columella very indistinctly or not folded, narrow, 

 nearly straight in the middle, its edge narrowly reflexed, expanding in 

 the axial region. The specimens figured measure : 



Length 16, diam. 10.5, length of aperture 10.8 mm.; whorls 5. 

 " 16 " 9.3 " " 9-7 " " 43/4 . 



16 " 10 " •' 9.4 " " 5. 



15 " 10 " " 9.7 " " ^y^. 



15.3 " 9 " "9 " " 5- 



Spring on the Rio Chico, 25 miles above the Sierra Oveja (figs, i, 2, 

 4, 6). Small stream, 35 miles above Sierra Oveja (fig. 5). 



The specimens from the second locality mentioned are more regular in 

 contour. Up to a length of 15^^ to 16 mm. the surface shows no mallea- 

 tion, and at that size the shells of this lot reach maturity. The lip 

 expands slightly and a very thin, white, submarginal callus strengthens it. 

 In one individual growth has proceeded beyond this stage, the part added 

 being strongly malleated. This shell (PI. XLVI, fig. 5) measures, length 

 17, diam. 10, length of aperture 9.8 mm.; whorls 5. 



In two of the four lots from "springs on the Rio Chico, 25 miles above 

 Sierra Oveja," there are some dwarf individuals. One measures, length 

 10, diam. 6, aperture 6.5 mm.; whorls 4J4 . In another lot, all the shells 

 are similarly dwarfed. 



In the Rio Chico, 50 miles above Sierra Oveja, a similar dwarf shell 

 was taken. 



In and near drying pools on a high divide near the base of the Andes, 

 50 miles north of the Rio Chico, elevation 2400 ft., the shells are very 

 fragile, pale, dull buff, with strongly developed, low, wave-like costation 



