[gutvol-d] Internet Archive PG collection

Hello all. I was browsing the Internet Archive texts and saw that they have a link to their own Project Gutenberg collection. When I followed it, they only listed 7,389 items. Why is this? There should be over 17,000, right? They are all available via ftp.archive.org I believe, so why aren't they listed on their web site? To see this, go to http://www.archive.org/ and go to texts. Select the Project Gutenberg link. Are things not being mirrored properly from the PG catalog?