A cloud with an arrow pointing down...what does it mean?

In my iTunes when I put "everything" to the cloud most of my music was transported to the cloud but some is marked with an arrow pointing down inside the iCloud symbol next to the songs... The songs also appear to be lighter in shading than others. What I don't know is what that symbol means? I know that the songs / albums should be in the cloud because some of them are Beatles songs.... so I know they are in the cloud ... Can anybody help me?