I've noticed that when you click on a `<select>` [element in Twitter Bootstrap](http://twitter.github.com/bootstrap/base-css.html#forms), the options that pop up have unstyled fonts. 

Default element, with Helvetica text: 

![enter image description here](https://i.stack.imgur.com/ytopn.png)

Unstyled element, with Arial(?) text:

![enter image description here](https://i.stack.imgur.com/mZxmX.png)

Is there any way to style what appears when you click on a `<select>` element, or does this depend on the browser?

It's not very noticeable in base Bootstrap, but I'm using a different (serif) font, and it jars badly.