Butterfly Pavilion’s spiders are back Saturday-Oct. 31. Most visitors to Westminster’s Butterfly Pavilion know of the lovable (er, mostly) mascot Rosie the Tarantula. But if she’s not enough for you, check out the Sept. 21-Oct. 31 return of “Spiders Around the World.” The limited-time programming leads up to Halloween with a stunning diversity of spiders sprinkled throughout the facility. No, they’re not all in captivity.