46 THE NAUTILUS. 



though when the soft parts and operculum come to hand it is quite 

 possible that the Mexican snails may prove to be generically distinct 

 from the Dalmatian. They differ chiefly by wanting a swelling be- 

 hind the expanded lip, and for this reason I erect for them the sub- 

 genus Emmericiella, type E. novimundi. 



The Oriental group Tricula Benson, with a few Indian and 

 Philippine species, resembles Emmericiella, but the inner lip is 

 straightened, making the aperture narrow and piriform. 



Emmericia (Emmericiella) novimundi q. sp. PL 5, figs. 9, 10. 



The shell is imperforate but openly rimate, rather solid, ovate- 

 conic, smooth and glossy. Tlie spire is straightly conic, apex obtuse, 

 the tip being depressed. Wliorls 4^, convex, separated by rather 

 deep sutures ; last whorl well rounded, ascending to the aperture. 

 The aperture is oblong, vertical, or has the basal lip a little ad- 

 vanced. Peristome continuous, well expanded, thickened on the 

 face and within ; the outer lip is just perceptibly retracted near the 

 upper insertion ; basal margin well rounded ; columella concave, 

 thick. Parietal callus heavy, adnate, but with distinct edge in fully 

 adult shells, spreading forward in front of the aperture. Length 3.1, 

 diam. 1.9 mm.; longest axis of aperture, including peristome 1.65 

 mm. (fig. 10). 



Bank of Choy River near the cave, State of San Luis Potosi. 



The specimens are bleached ; color in life unknown. These are 

 two perfect examples of the same size. "With these are associated 

 several decidedly larger shells, in which the apex is broken, prob- 

 ably one whorl being lost. One of these — figured in profile, fig. 9 — 

 measures, length 3.5, aperture 1.9 mm., 4 whorls remaining. 



Emmericia (Emmericiella) longa n. sp. PI. 5, figs. 11, 12. 



The shell resembles E. novimundi but is more shortly rimate, of a 

 turrited shape, with 5^ more convex whorls. Aperture is more 

 produced forward below, and the parietal callus spreads forward less. 

 The outer and basal margins are well expanded. Length 4.1, diam. 

 2, longest axis of aperture including lip 1.6 mm. 



Two complete and one broken specimen, found with the preceding 

 species. 



The new subgenus Emmericiella is proposed for American 

 Emmericiae, in which there is no wave or ridge behind the lip-ex- 

 pansion, and the columellar margin of the aperture is built forward 



