THE CLIMAX FOREST AND ITS PREDECESSOR 217 



larger shells. P. multilineata and P. prof undo, are marked with 

 revolving brown bands and are the only ones so marked: the 

 former has no umbilicus; the latter, a very wide one. P. albo- 

 labris has the umbilicus completely covered, P. pennsylvanica, 



FIG. 286 FIG. 287 



FIGS. 286, 287: Fig. 286. Under side of head end of common mole, Scalopus 

 aquaticus; Fig. 287. White-footed deer mouse, Peromycus leucopus, and imprint 

 of fore and hind foot, reduced one-half. 



nearly covered, P. thyroides about half-covered. The latter is 

 distinctly striate with fine ridges. P. clausa is similar but 

 unstriate, and the shell is high as compared with that of 



P. thyroides. 



The Pyramidulas do not 

 have the reflected lip. 

 Their shells are quite flat 

 and coarsely striate. P. per- 

 spectives and striatella are 

 small. The former, .5 inch 

 in diameter, reddish in 

 color, has six and one-half 



FIG. 288. The common slug, Agriollmax whorls. The latter, .25 



campestris. mc h j n diameter, is brown 



in color and has only four whorls. P. solitaria has three 

 spiral brown bands, while P. alternata is marked with alternate 

 patches of dark and light. The Omphalinas have paper-thin 

 polished shells. O. fuliginosa is mahogany brown with a pearly 

 aperture. O. friabilis is similar, but the shell is still thinner. 

 Zonitoides arboreus is small, only .12 inch in diameter. The shell 



