The Collaborative International Dictionary of English v.0.48:

Phenogamian \Phen`o*ga"mi*an\, Phenogamic \Phen`o*gam"ic\,
Phenogamous \Phe*nog"a*mous\, a.
   Same as Ph[ae]nogamian, Ph[ae]nogamic, etc.
   [1913 Webster]