1. Mrs. Long

2. Mr. Morris
3. Sir William & Lady Lucas
4. Mrs. Long's nieces family (let's call them the Shorts)
5. Miss King
6. Mr. Robinson
7. Col. Forster
8. The Phillips
9. Miss Watson
10. The Clarkes
11. Mr. Jones
12 Harriet & Pen Harrington These 2 seem to be friendly with Lydia and Mrs. Forster, so I imagine they are relatively young ladies. -- Chapter 39

In Chapter 39, we also learn a few of the officers name -- Chamberlayne and Pratt.