In 1972 I found for the first time the brown or "fawn" colored form of
Cepaea nemoralis in the growth where the railway tracks  pass through the
Surrey beachfront community of Crescent Beach, south of Vancouver, British
Columbia.
 I did not know what I was finding at first, not knowing that a brown form
of this species even existed. I had not seen the brown color form before,
either in Canada or in my native Denmark where my interest in shells began
and where C. nemoralis is very common. It was only after searching the area
for several times that I found the first yellow striped specimen and I then
knew what it was that I was finding there. In later years I found the brown
form in other areas of Surrey and have found it and the other color forms
and varieties in my own garden in Richmond.
 Predation by birds and animals is deffinitely instrumental in which color
forms are dominant in a particular colony. The brown form in Crescent Beach
was difficult to detect while the brighter colors stood out. In 1976 I
found a "bird anvil" at this location with about 38 broken C. nemoralis in
a pile beside a bottle. One quarter of the shells were yellow striped and
the rest of them were the brown color form. Rats are the chief predators of
C. nemoralis in Richmond where I live, I have found broken shells in rats
nests a number of times.
George Holm
Richmond, B.C. Canada



>>Also, there have been studies regarding the various color forms of Cepaea
>>nemoralis, concerning what relationship shell color and pattern may have
>>to the environment...are certain color forms more abundant in some
>>habitats and less so in others. (Does anyone have the references that I
>>am referring to?? I just remember being told about them in evolution
>>class.) <
>Studies on a variably patterned land snail, I think Cepaea, showed that
>the variable shell patterns worked to confuse visual predators such as
>birds.  If a bird finds a solid bright yellow shell and starts to look for
>more like it, he may overlook duller shells with stripes.  Any one pattern
>that becomes more common attracts the attention of predators, whereupon it
>becomes rarer.
>
>    Dr. David Campbell
>    Old Seashells
>    University of Alabama
>    Biodiversity & Systematics
>    Dept. Biological Sciences
>    Box 870345
>    Tuscaloosa, AL  35487 USA
>    [log in to unmask]
>
>That is Uncle Joe, taken in the masonic regalia of a Grand Exalted
>Periwinkle of the Mystic Order of Whelks-P.G. Wodehouse, Romance at
>Droigate Spa