COLLINGE: BURROWING HABITS OF CERTAIN MOLLUSCS. fag 
Hyalina glabra Stud. Mr. Rhodes records two specimens with 
preceding species. I have met with it at a depth of about five 
inches, never deeper. 
Hyalina nitidula Drap. I have not as yet met with this species 
below the surface. Rimmer states that ‘it is a timid species, 
and often buries itself in the earth.’ 
Hyalina crystallina Miill. Under very heavy stones I have on 
many Occasions in the summer met with this shell; the greatest 
depth the stones were imbedded was six inches. 
Helix pomatia L. Most authors regard this species as only 
burrowing an inch or two and only when hybernating. 
neues Bags ae siee Mill. This well-known species can hardly be 
d to burrow at all; during the time of depositing the eggs, 
shee scoop out a hole two or three inches deep. I have taken 
young specimens in winter at a depth of four inches. The 
absurd properties attributed to molluscs reach their climax when 
such authorities as Bouchard-Chantereaux and Dr. Buckland 
tell us that this species scoops out by some means or other holes 
in limestone rocks, in which they hybernate. Some authors are 
of opinion that the rock is worn away by an acid secretion, 
others by the action of the shell and some by the rasping of the 
mandible. That they hybernate in such places I admit, but they 
are in no way responsible for the excavation. 
Helix rufescens Penn. Frequently met with at a depth of from 
four to six inches and during hybernation in the hollows of 
decaying trees. I have on one occasion met with this species 
in the burrows of earthworms some six inches below the surface. 
It is possible that they had been dragged in by the earthworms, 
but hardly likely as they seldom, I believe, take in other than 
vegetable matter 
Helix hispida L. Found with the preceding species in burrows. 
of earthworms. 
Helix rotundata Miill. Burrows from four to five inches. 
Found in both summer and winter. Very often found in earth- 
worm burrows. 
Helix rupestris Drap. Generally beneath growths of moss, etc., 
on old walls, four and five inches in thickness. - 
Bulimus obscurus Miill. Occasionally taken at _— varying 
from four to six inches. 
epee * “es Drap. Generally with preceding species. 
March 189 18 
