▁ver r illi ▁( V an ▁Name , ▁ 1 9 1 2 ) ▁ ▁Mol g ula ▁ver ru c if era ▁Ritter ▁& ▁F ors yth , ▁ 1 9 1 7 ▁ ▁Mol g ula ▁x en op hora ▁O ka , ▁ 1 9 1 4 ▁ ▁References ▁ ▁Further ▁reading ▁▁ ▁How son , ▁C . ▁M .; ▁Pic ton , ▁B . ▁E . ▁( Ed .) ▁( 1 9 9 7 ). ▁The ▁species ▁directory ▁of ▁the ▁marine ▁fa una ▁and ▁fl ora ▁of ▁the ▁British ▁Is les ▁and ▁surrounding ▁se as . ▁Ul ster ▁Museum ▁Public ation , ▁ 2 7 6 . ▁The ▁Ul ster ▁Museum : ▁B elf ast , ▁UK . ▁. ▁vi , ▁ 5 0 8 ▁(+ ▁cd - rom ) ▁pp . ▁ ▁Mon ni ot , ▁C . ▁( 2 0 0 1 ). ▁As cid ia ce a ▁& ▁Sor ber ace a , ▁in : ▁Cost ello , ▁M . ▁J . ▁et ▁al . ▁( Ed .) ▁( 2 0 0 1 ). ▁European ▁register ▁of ▁marine ▁species : ▁a ▁check - list ▁of ▁the ▁marine ▁species ▁in ▁Europe ▁and ▁a ▁bibli ography ▁of ▁gu ides ▁to ▁their ▁identification . ▁Collection ▁Pat r imo ines ▁Nature ls , ▁ 5 0 : ▁pp .   3 5 2 – 3 5 5 ▁ ▁San am yan , ▁K . ▁( 2 0 0 7 ). ▁Database ▁of ▁ext ant ▁As cid ia ce a .