38 THE NAUTILUS. 



slightly exceeding one-third the length of shell, ovate, the outer lip 

 strongly arcuate above, columellar margin flattened above; per- 

 istorae continuous, the adnate parietal portion longer than in 1'. 

 /apidaria. Alt. 6, diam. o-5 mm. 



Black Falls, above Flormce, Alabama (A. A. Hinkley, 1894). 



The species is somewhat intermediate between P. lapiduria and P. 

 cincinnatiensis, but more like the former, from which, however, it is 

 very easily distinguished on comparison. The form is stouter, the 

 aperture larger, the outer lip more strongly curved above, and the 

 color duskier. The apex is somewhat eroded in all of the well 

 grown specimens. The dentition is similar in general characters to 

 that of P. lapidaria. 



I am indebted to Mr. Bryant Walker for the specimens, which 

 were collected by Mr. Hinkley. Upon inquiry, my correspondent 

 quotes as follows from Mr. Hinkley's letter: " Most of the distance 

 from Florence to the last lock of the canal there is a steep rocky 

 bank ; a few rods from the water of the river over this bank and out 

 of it are several small streams and springs of clear water. The 

 species under consideration was seen at most of these small streams 

 but was not numerous except at the two falls from which they were 

 taken. Three forms of Goniobasis were taken from the same streams. 

 Now, while the Goniobasis were in the water, the others were not. 

 They were taken from moss and decaying vegetation but were kept 

 damp by the spray of the falls or by the dripping water under the 

 rock back of the falls and the saturated moss. As I made a hurried 

 trip the day I collected these shells, they were not examined closely, 

 but I took it for granted they were feeding iu the decaying vegeta- 

 tion. None of them were found beyond the reach of the spray but 

 still they might have been hidden under the rubbish." 



From this the new species appears, as Mr. Walker remarks, to be 

 clearly Pomatiopsine in habits. In choosing a specific term for the 

 form, I have acted upon the suggestion of Mr. Walker that the name 

 of one of our best collectors be associated with this interesting 

 species. 



THE WEIGHT AND SIZE OF "SHELLS. 



BY REV. HENRY W. WINKLEY. 



With the assistance of Mr. D. E. Owen, teacher of Physics in 

 Thornton Academy, the writer has weighed a few species of minute 

 shells. The results are given as follows : 



