626 PEOCEEDINGS OF THE ACADEMY OF [DeC, 



layer extending for nearly a quarter turn beyond the mouth and 

 heavily thickened at the umbilical region. 



Greatest diam. 5.5, least diam. 4.75, alt. 4.5 mm. 



About forty, specimens of this very pretty species were taken 

 under dead leaves near the limestone quarries at Ceara-Mirim. 

 About a quarter were living and seemed to be astivating. A single 

 specimen of the same species ''from the State of Ceara" was sent 

 by Mr. Rocha. The species may be distinguished by its small size, 

 thin texture, and coarse spiral sculpture, and it is not related to any 

 described species. It is named for Dr. C. A. Scherer, of the Medical 

 Corps of the Madeira-Mamore R. R., who was our host at Camp 39 

 and who aided us greatly in our hunt for zoological material. 

 Helioina guajarana n. sp. Pl. XXI, fig. 3. 



Shell rather thin, imperforate, subglobose, with straight sides; 

 epidermis thin, color light yellow throughout, slightly shining; apex 

 rather acute, slightly mammillate; nepionic 1| whorls suggestive 

 of Drymmis, but with the pits placed irregularly, though somewhat 

 on spiral lines; post-nepionic whorls everywhere marked by micro- 

 scopically distinct, very strongly retractive growth lines which are 

 sharply decussated by equally protractive, fasciculated, incised 

 lines, which divide and anastomose irregularly, the growth lines 

 becoming more nearly vertical as they pass the periphery and 

 approach the umbilical region, while the incised lines become more 

 nearly spiral and less distinct. Whorls 4|, slightly convex; periphery 

 of the last whorl scarcely angulate except over the first quarter turn, 

 not descending in front; sutures distinct. Aperture subelliptical, 

 subhorizontal; peristome rather evenly rounded, thickened and 

 expanded moderately, joining the columellar base with a distinct 

 angulation; columella short, nearly vertical, spreading above into 

 the broad, thin callus which covers the slightly convex parietal wall. 



Greatest diam. 6.5, least diam. 5.25, alt. 5.75 mm. 



One living and two dead specimens of this species were taken near 

 the Guajara-Assu Falls. The species is somewhat related to the 

 larger H. bourguignatiana Ancey, but is differently colored and has a 

 less marked angle at the junction of the columella and basal lip. 

 Helicina laterculus n. ep. Pi. xxi, figs. 4, 5. 



Shell globose-depressed, rather thin, of a dull red color, smooth 

 .except for faint growth-lines. Spire low-conoidal; whorls 4^, very 

 slightly convex, the last rounded peripherally. Aperture small; 

 outer lip thin, a little expanding, and very narrowly reflected. Colu- 



