[jQuery] Can I select and/or ?

[rolfsf]

I've got a table in which I've set up some column groups.
<colgroup class="location">
    <col></col>
</colgroup>
<colgroup class="year">
    <col class="this"></col>
    <col class="that"></col>
    <col class="that"></col>
    <col class="that"></col>
</colgroup>
<colgroup class="year">
    <col class="this"></col>
    <col class="that"></col>
    <col class="that"></col>
    <col class="that"></col>
</colgroup>
...

Ideally, I'd like to be able to toggle the visibility of the <col
class="that"> - can I select them as cols in jquery, or do I need to
get at them via the rows?

Thanks!