animal bat black bulgaria caucasus circa collection colony communication correspondence down drawing emarginatus equinum ferrum ferrumequinum georgia greater horseshoe mail mammal mark nature nocturnal old paper philately picture pipistrellus portrait post postage postal postmark retro rhinolophus send stamp upside vintage wild wildlife background brown cave caveman closeup dark ear Eared ecosystem face flying fruit fur hanging hibernation isolated largest limestone long long-eared membranes night premolar rock scary sedentary sleeping Underground upside-down wing