A female dog tick (Dermacentor variabilis) after removal has a piece of tissue attached to its proboscis.
Well, the good news was, I found out my dog’s flea and tick treatment was effective against dog ticks; the bad news was I found it was effective. Pulled maybe ten, maybe a dozen of the suckers off her? Most died after attachment. Insidious creatures, but interesting photo subjects if you ask me. (Black and white version below.)
A female dog tick (Dermacentor variabilis) after removal has a piece of tissue attached to its proboscis. (Black and white version.)
BugPhoto.net 
“Insidious creatures” is a good term for them. It kind of looks like a flattened out walnut with legs.
Now that is one seriously good macro!