Things will get a little batty in Old Sacramento Saturday when Trail Mix and a wildlife rescue group team up to educate people about bats. Corky Quirk, founder of Northern California Bats, will bring live, wild bats to help dispel some of the myths about these nocturnal creatures. She will also teach people about the benefits and habits of the mysterious winged mammals in a presentation from 1-3 p.m. at Trail Mix, a store selling outdoor merchandise for kids and parents at 116B I St., across from the California State Railroad Museum. Thousands of bats roost in the nooks and crannies of the city. In summer, a colony of 150,000 to 200,000 bats live under the Yolo Causeway and may be seen f