LAND SNAILS. 153 
The Chrysalis Snails, or Pupe, are so named 
from the fancied resemblance of their shells to 
an insect in the second stage of its metamor- 
phism—that is, to a chrysalid ; also to dolls or 
puppets. 
The shell is cylindrical or oblong, with many 
narrow whorls, minutely umbilicated; the aper- 
ture is oval or lunate, generally toothed within ; 
the peristome is incomplete, thickened, and re- 
flected. 
The Pupe are widely distributed on the globe ; 
the majority of them inhabit South-eastern 
Hurope. Four species are indigenous to this 
country and, excepting LP. secale, are found fos- 
silized in the Newer Tertiaries of the East of 
Eneland. Pupa is the most ancient genus of 
the land mollusca, the earliest known species of 
which is P. vetusta, of the Coal-measures of 
Nova Scotia. Two species are extinct in the 
Upper Eocene of the Isle of Wight. The species 
now inhabiting Britain may be characterized as 
follows :— 
1. re tooth, or edentulous tte tee nee ee 
Aperture with Many teeth picshi he. tred. . aaeyere ove 
Tooth in the upper angle of the outer oan umbilicata 
Peristome with external rib, tooth central,—P. muscorum 
3 Shell ventricose, shining, 5-toothed ... P. anglica 
Shell cylindrical, dull, 8-toothed ... ... ... P. secale 
Pura umBiLicaAta—(the Umbilicated Chrysalis 
