The links will take you to the AKC Breed Standards page for both breeds. The first picture is a Cardigan with the colourings we see most often (above).
The Cardigan can also be a blue merle colour. I think the GTB dog listed below likely has a bit of Cardigan in him (along with JRT). Again, this is a guess as I don't really know what breeds the dog is being a shelter adoption, but we can always put forth our opinions!
I saw a few blue merle Cardigans in the herding trial I went to a few weeks ago (very interesting stuff, I might add).