Thursday Night Nielsen Ratings: GRIMM Airs, PRIVATE PRACTICE & GREYS Have a Bye Week, SECRET CIRCLE & VAMPIRE DIARIES Repeat

Here's a look at the preliminary Nielsen ratings for Thursday, December 8, 2011:

- GRIMM made a special appearance with a 1.6 Adults 18-49 rating on about 4.1 million viewers.

- THE VAMPIRE DIARIES and THE SECRET CIRCLE repeated.

- GREY'S ANATOMY and PRIVATE PRACTICE had a bye week.