http://www.seaslugforum.net/showall/philauri
http://slugsite.us/bow/nudwk127.htm
http://www.seaslugforum.net/showall/philunk
http://www.calacademy.org/research/people/things/philin.htm
http://www.medslugs.de/E/Pac-SW/Philine_auriformis/Selection.htm