The number of described species of spiders is very high, over 30,000, and in principle, with the exception of a few groups (Uloboridae and Holoarchaeidae) which have no venom glands, all spiders must be considered as venomous. However, the World Health Organization 1 listed only four genera as responsible for severe human poisoning: Latrodectus, Loxosceles and Phoneutria (infraorder Araneomorphae) and Atrax (infraorder Mygalomorphae). A number of cases of spiderbites are described in the literature, involving different species. Maretic and Lebez 2 discussed the problem of the bites of Lycosa tarentula, considered for a long time to cause a necrosis of human skin. Levi and Spielman 3 related five probable cases of poisoning by Chiracanthium mildei, a spider living inside houses in the vicinity of Boston, U.S.