The Collaborative International Dictionary of English v.0.48:

Basommatophora \Ba*som`ma*toph"o*ra\
   (b[.a]*s[o^]m`m[.a]*t[o^]f"[-o]*r[.a]), n. pl. [NL., fr. Gr.
   ba`sis base + 'o`mma eye + fe`rein to bear.] (Zool.)
   A group of Pulmonifera having the eyes at the base of the
   tentacles, including the common pond snails.
   [1913 Webster]