LAND SNAILS. 
153 
The Chrysalis Snails, or Pupae, 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 Pupce are widely distributed on the globe ; 
the majority of them inhabit South-eastern 
Europe. Four species are indigenous to this 
country and, excepting P. secale, are found fos¬ 
silized in the Newer Tertiaries of the East of 
England. 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 
j ( One tooth, or edentulous .. . 2 
\ Aperture with many teeth . .. 3 
2 ( Tooth in the upper angle of the outer lip,— P. umbilicata 
l Peristome with external rib, tooth central,—P. muscorum 
^ ( Shell yentricose, shining, 5-toothed ... P. anglica 
\ Shell cylindrical, dull, 8-toothed ... P. secale 
Pupa umbilicata — -{the Umbilicated Chrysalis 
