Double Spathe Calla palustris

[Brian Cook]

I found a Calla palustris growing on my property that has two spathes
instead of the usual (to me at least) one. I was wondering how common
an occurrence this is and if this trait is likely to be passed on via
the seeds? In a conversation about this with a local friend, it was
suggested that it may be simply an enviornmental response and that
next year it may be back to normal, (I hope not!) any thoughts on
this?

The spathes were opposite, mounted just slightly above each other and
held horizontally at almost 90 degrees to the spadix. The second one
is smaller by about 1/3 but otherwise similar in appearance. This is
the only bloom like it in small clump of otherwise normal ones.

I am hoping some of you may be able to provide some input on this.
Aroids are a fairly new interest for me so it is hard to know what
constitutes something that is "different and interesting" or is simply
a case of  "oh that old thing, I just composted 75 of em last week". 

Thank you
Brian Cook