MapActivity:

public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.weather_map_layout);

      mapView = (MapView) findViewById(R.id.myMapView);

      Bundle extras = getIntent().getExtras();

      float lat = extras.getFloat("latitude");
      float longi = extras.getFloat("longitude");
....


ListActivity:

....

protected void onListItemClick(ListView l, View v, final int position, long id) {

        super.onListItemClick(l, v, position, id);
        Intent newIntent = new Intent(ListarLocaisActivity.this, MapaActivity.class);

        Place coordenadas=listAdapter.getItem(position);
        double lat = coordenadas.getLatitude();
        double longi = coordenadas.getLongitude();

        newIntent.putExtra("latitude", lat);
        newIntent.putExtra("longitude",longi);

        startActivity(newIntent);
        }