Cloud Creations

On my way to work there was an intriguing and aesthetically pleasing cloud formation sweeping across the sky. Mottled, a bit like fish scales, or closely clustered cells. Stretching out to look like a collection of cotton balls. I'm sure there is a name for it, anybody know what it is?

This super-quick snap was the best I could grab unfort as I was heading into the building at work. Really I saw the best of it whilst on route to work, but it seemed rather irresponsible to try snapping cloud pics while I was bombing it up the motorway... ;)