122 THE NAUTILUS. 



in number 7^, are convex and separated by a deep suture. The 

 last whorl is a little longer than the spire, descending only at 

 its end. The apex is obtuse, first ascending then descending, 

 smooth, shining. The two embryonic whorls are sculptured 

 with irregular longitudinal wrinkles and numerous vpry fine 

 pores, which exi&t also in some of the following whorls. The 

 whorls of the spire are ornamented with feeble longitudinal ribs 

 which are somewhat irregular and sometimes bifid and with 

 numerous impressed spiral lines. The aperture is small, some- 

 what oblique, occupying one-third of the total length of the 

 shell. The peristome is sharp, simple, the columellar lip dilated 

 above, reflected, somewhat thickened and covering the umbilical 

 chink. The parietal callus is broad, white, and forms a straight 

 line connecting the outer lip with the columella, with which it 

 forms an obtuse angle. 



The length of the shell is 19.5, the diameter 7.3, the alt. of 

 the aperture 6.5, the diameter of the aperture 4 mm. 



The unique specimen, found at the Brazilian Island of Trin- 

 ity, is kept in the National Museum of Rio de Janeiro. The 

 species is dedicated to my distinguished colleague, Prof. Dr. 

 Bruno Lobo, Director of the National Museum of Natural His- 

 tory and Anthropology at Rio de Janeiro. 



House de Joinville, Est. de St. Catharine, Brazil, 

 20th of September, 1916. 



PLEUEOCERA SUBULARE LEA. 



BY CALVIN GOODRICH. 



Lea's Melania subularis^ came from the Niagara river. It is 

 a shell common to the waters of Lake Erie, especially the north- 

 ern and western shallows. A form, recognizable superficially as 

 different, occurs in the lake tributaries. These river shells, as 

 a rule, are lighter of structure, less polished and, whorl for 

 whorl, somewhat larger than lake shells. The percentage of 

 dark shells in the streams is, I would say offhand, lower than in 



jphUos. Trans. IV., p. 100; 1831. 



