[jQuery] getting code from/between

Hi,

I would like get get/copy code between html tags, like this:
<fieldset>
<legend>some...</legend>
<label id="n1">some input</label>
<label id="n2">some next input</label>
<label id="n3">next input</label>
</fieldset>

I want set to variable code from </legend> to <label id="n3">
(between)
How do this?