I would agree it does suggest that they need dividing,this link will tell you how;

http://www.thegardenersalmanac.co.uk/Data/Iris-Bearded/Iris%20-%20Bearded.htm

I inherited a garden with a partially shaded bed crammed full of pale bearded iris (no idea what variety) that never came to very much, so, after the flowering season, I dug it out, divided all the rhizomes up into small bits and replanted them down the side of our very long drive in full sunshine. It's taken a couple of years, but this year, for the first time, we have the most beautiful display of flowers, all a lovely deep shade of purple. They are obviously much happier being spread out and uncrowded, and I shall do the same again in a couple of years.

Yes mine are in need of dividing and unfortunately I think a mouse has chewed one of the flower head stems and snapped it off - I know a mouse lives nearby. I have painted the rest of the stems with madras curry powder - that should give him/her a nasty surprise!

Could be a well-travelled mouse. He might love it!

We shall see. I'm not doing popadoms with it!!

Thanks, loving the mouse thing,we just have rabbits,like watership down on steroids

That's the first time I've laughed out loud today, Jenfren! We don't seem to have rabbits round here - maybe the hunters get them all, but we get great big, lollopy hares instead. Yummy!