French Gender (Confusing!) PARADOX

 Final -e is known to be French female marker for nouns referring to 

• human beings : ami m. boyfriend > amie f. girlfriend , 
• animals: lion m. > lionne f., 

and for adjective agreement :  

• un grand sac m. a big bag >  une grande avenue f. a big avenue. 

Nevertheless, when it comes to nouns other than the ones referring to human beings, this is not that simple.  

Thought it is perfectly fair to say: 

"feminine nouns end with an -e in French", as more than 7 feminine nouns out of 10 do so, 

the other way around cannot be stated: 

"final -e is NOT the marker of feminine gender in French", as we find as many masculine nouns bearing a final -e than feminine nouns.  

This paradox gets everyone confused... 

There is a clear gender to form relationship : 

feminine gender means greater chance to find a final -e than any other endings.

Where as the opposite (form to gender relationship) is not exactly true : 

nouns ending with an -e are not clearly more likely to be feminine.

From Mauvais Genre : Gender of French Nouns