In the galleries folder, there is a subfolder for each gallery type.
in each gallery type folder there is an admin/design.xml file that setts the description..
so for example in the galleries/ribbon_lightbox_powerstore/admin/design.xml file, the referance to power store is in the description tag:
<description>Scrolling ribbon of 8 images with tooltips and a lightbox effect. Designed to work on a PowerStore product detail page.</description>