this website exists no more:
http://www.biology.ucsc.edu/classes/bio161l/NUDI/dcolumbi.html
http://www.seaslugforum.net/showall/dotocfcolu
http://www.medslugs.de/E/Pac-NE/Doto_columbiana/Selection.htm
http://www.nudipixel.net/species/doto_columbiana/