Lyencephala

• (n. pl.) A group of Mammalia, including the marsupials and monotremes; -- so called because the corpus callosum is rudimentary.
Found on http://thinkexist.com/dictionary/meaning/lyencephala/

Lyencephala

Ly`en·ceph'a·la noun plural [ New Latin , from Greek ... to loose + ... the brain.] (Zoology) A group of Mammalia, including the marsupials and monotremes; -- so called because the corpus callosum is rudimentary.
Found on http://www.encyclo.co.uk/webster/L/72
No exact match found