Let $F$ be a $C^3$ diffeomorphism on a Banach space $B$ . $F$ has a
homoclinic tube asymptotic to an invariant manifold. Around the
homoclinic tube, Bernoulli shift dynamics of submanifolds is
established through a shadowing lemma. This work removes an
uncheckable condition of Silnikov (1968). Also, the result of Silnikov does not imply
Bernoulli shift dynamics of a single map, but rather only provides a
labeling of all invariant tubes around the homoclinic tube. The
work of Silnikov was done in ${\mathbb R}^n$ and the current
work is done in a Banach space.