28 THE NAUTILUS. 



Length 9.8, diam. 2.9 mm. 



El Abra, State of San Luis Potosi, Mexico, collected by A. A. 

 Hinkley. 



This species is well characterized by the freely descending last 

 whorl, the " neck " being much longer than in any other member of 

 the typical subgenus of Holospira. The four internal laminae are 

 well developed, and situated somewhat lower than in H. yoldfussi. 

 Eight specimens were taken, part of them immature. 



ZONITOIDES PENTAGYRA n. Sp. PI. Ill, figs. 6, 7, 8. 



The shell is slightly larger than Z. minuscula, umbilicate, the 

 width of the umbilicus contained between 4 and 4| times in that of 

 the shell; thin, whitish in the dead specimens seen, similar in color 

 to Z. minuscula. Surface glossy, marked with very weak growth- 

 lines, and with very faint fine spiral striae on the base, more distinct 

 in immature shells. 



Spire quite convex. Whorls 5, narrow and very slowly increasing, 

 convex, the last well rounded peripherally. Aperture somewhat 

 oblique, quite small, and narrowly lunate. Peristome simple as usual. 



Alt. 1.4, diam. 2.7 mm. 



Tampico, in river drift, with Z. minuscula and Z. singleyana and 

 various Pupillidce, etc. Type no. 93796 A. N. S. P., from Mr. 

 Hinkley's collection. 



This species is readily distinguished from the two associated forms 

 of Zonitoides by the closely coiled whorls and the small, narrowly 

 lunate aperture. It has some resemblance to Pycnogyra bercndti, of 

 the region of Vera Cruz. It is comparatively rare in the river 

 debris, while Z. minuscula and singleyana occur in copious quantity. 



SPIRAXIS TAMPICOENSIS Pilsbry. PI. Ill, fig. 5. 



Drift debris at Tampico. This very slender shell has been de- 

 scribed in the current number of the Manual of Gonclioloyy, p. 24. 



CECILIOIDES (C^ECILIANOPSIS) JOD n. sp. 



The shell is iniperforate, very minute, oblong, slowly tapering to 

 an obtuse summit, whitish (probably clear corneous when living), 

 smooth and glossy. Whorls 4, slightly convex. Aperture less 

 than half the total length, piriform, shaped like that of Euglandina, 

 the outer lip arcuate, thin, columella very concave, covered with a 

 thin callous film, distinctly truncate at the base. Length 2.1, 

 diam. 1 mm. 



