  Let $G_n$ denote either the group $SO(2n+1, F)$, $Sp(2n, F)$, or $GSpin(2n+1,
F)$ over a non-archimedean local field of characteristic different than two. We
determine all composition factors of degenerate principal series of $G_n$,
using methods based on the Aubert involution and known results on irreducible
subquotiens of the generalized principal series of particular type.
