From: Miguel Carrasquer
Message: 31948
Date: 2004-04-16
>Miguel:The difference is that vowel + m# never lengthens, so
>> What we find is an ins.pl. in *-o:ys, which _could_ mean
>> that the "plural" *-s _did_ have a lengthening effect,
>
>Well then, we could say that *m has a lengthening effect
>in the thematic gen.plural too.