Untitled

$('.span3')
[<div id="68" class="span3">…</div>,<div id="67" class="span3">…</div>,<div id="66" class="span3">…</div>,<div id="64" class="span3">…</div>,<div id="63" class="span3">…</div>,<div id="62" class="span3">…</div>,<div id="61" class="span3">…</div>,<div id="60" class="span3">…</div>,<div id="59" class="span3">…</div>,<div id="58" class="span3">…</div>,<div id="57" class="span3">…</div>,<div id="55" class="span3">…</div>,<div id="54" class="span3">…</div>,<div id="21" class="span3">…</div>,<div id="20" class="span3">…</div>,<div id="19" class="span3">…</div>,<div id="14" class="span3">…</div>]
$('.span3:not(#68)').first()
[<div id="67" class="span3">…</div>]
$('#68').remove();
$('.span3:not(#68)').first().addClass('first')
[<div id="67" class="span3 first">…</div>]
$('.span3')
[<div id="67" class="span3 first">…</div>,<div id="66" class="span3">…</div>,<div id="64" class="span3">…</div>,<div id="63" class="span3">…</div>,<div id="62" class="span3">…</div>,<div id="61" class="span3">…</div>,<div id="60" class="span3">…</div>,<div id="59" class="span3">…</div>,<div id="58" class="span3">…</div>,<div id="57" class="span3">…</div>,<div id="55" class="span3">…</div>,<div id="54" class="span3">…</div>,<div id="21" class="span3">…</div>,<div id="20" class="span3">…</div>,<div id="19" class="span3">…</div>,<div id="14" class="span3">…</div>]
After callback:
$('.span3')
[<div id="66" class="span3">…</div>,<div id="64" class="span3">…</div>,<div id="63" class="span3">…</div>,<div id="62" class="span3">…</div>,<div id="61" class="span3">…</div>,<div id="60" class="span3">…</div>,<div id="59" class="span3">…</div>,<div id="58" class="span3">…</div>,<div id="57" class="span3">…</div>,<div id="55" class="span3">…</div>,<div id="54" class="span3">…</div>,<div id="21" class="span3">…</div>,<div id="20" class="span3">…</div>,<div id="19" class="span3">…</div>,<div id="14" class="span3">…</div>]