2 different styles for h4

Im having some trouble with my css. I have to use 2 different styles for a h4 tag. I have no trouble getting the first h4 displayed, though I cant seem to get the h4.green displayed. What am i doing wrong

My css :

#navigate h4{
font:11px verdana, arial, georgia, sans-serif;
}

#navigate h4.green {
font:48px verdana, arial, georgia, sans-serif;
}


my html:

<div id="navigate">
<h4>normal</h4>
### some html


<h4 class="green">green</h4>
### some html
</div>

It works fine for me.