yup half bloods and pure bloods have been slytherins, so i'd bet a pure muggle has slipped through the cracks especially if he/she was especially talented or evil ;)  "You have talent and a thirst to prove yourself, slytherin can help you." (the hat to Harry)<br/><br/>Salazar himself would certainly not approve... but there is no test we know of or that has been written that would make it obvious your heritage. :)<br/><br/>If he doesnt work, then Vinny may find himself the victim of vicous canids or something along those lines ;)