this website exists no more:
http://www.biology.ucsc.edu/classes/bio161l/NUDI/dsubramo.html
http://www.seaslugforum.net/factsheet.cfm?base=dendsubr
http://slugsite.us/bow2007/nudwk557.htm
http://www.medslugs.de/E/Pac-NE/Dendronotus_subramosus.htm