Vinca

I had this with my Monarda one year. Fascinating isn't it!

Oh I hadn't seen that, strange or is it supposed to do that. :O)

There is a term for t, which I was told at the time of the Monarda...but I can't remember it.

in Primula I think its called 'Hose in hose'. 'Elizabethan style of Hosiery I think.

One of my roses used to do this, during the summer of 2012. i posted a photo and Noseypotter posted a comment saying that it was the rootstock coming through...

this is another flower bud so not a root stock.

Yes that was what my rose was doing, sending up a new bud through middle of the flower, i didn't quite understand his comment either but have just tried to google this phenomenon and came across another reference about a rose reverting back to it's rootstock , strange.
http://www.rose-gardening-made-easy.com/rose-buds-within-a-rose.html