Something Evil at Arcosanti

Some form of evil bug has colonized Arcosanti in the last month or so. Back in June I could sleep at night with my door open, and only worry about live or freshly-killed "presents" from my cats. Now if I leave the door open at night I wake up with welts like this one: I never even feel these creatures bite me, I only know they've been after me when their bites swell up and start to itch like mad. Luckily the swelling goes down by morning, but it takes a little while to get back to sleep after such a rude awakening. I guess I'll have to be extra careful about forcing the door fully shut until these monsters die off.