Jquery :: Use Each To Get Html Of Ul And Append It To Div?

im trying to look into a div and find each instance of a ul in that div and get all the li elements into a variable then remove the ul's and append the new ul with li from variable. here is what i have so far:

Code:

//var ulla = ' ';
jQuery("ul").each(function() {
var ulla = jQuery(this).html();
});

[Code]....

im trying to get all of the li elements from all ul elements and store them so I can remove all the multiple ul elements and make one ul and put all the li elements inside this new single ul. I keep trying variations of this with different selectors and forms of each and i cant get anything into that ulla variable, i get undefined when loading the page for ulla with code above.