Bring the wine to a boil in a medium saucepan. Add the mussels, cover and cook over high heat until they open, about 2 minutes. Using tongs, transfer the mussels to a bowl. Add the clams to the saucepan, cover and cook until they start to open. Transfer them to the bowl with the mussels. Pour the cooking liquid into a small glass measure, leaving behind any grit. Shell the mussels and clams and return them to the bowl.