Bay seniors and their grandkids are reminded to check the Academy of Sciences costume policy before getting dressed for their SuperNatural Halloween. You don’t want to alarm the cockroaches, tarantulas and snakes available for petting. But you will receive discounts for wearing an unthreatening costume. For the less fearless there are pumpkin carving demonstrations and magic shows. This Friday and Saturday afternoon til 5pm, leaving time to spare for trick or treating. If you find one day a year of this sort of macabre activity insufficient you sound like a candidate for the Bay Area Tarantula Society.