  A hole is an induced cycle of length at least 4. Let $\l\ge 2$ be a positive
integer, let ${\cal G}_l$ denote the family of graphs which have girth $2\l+1$
and have no holes of odd length at least $2\l+3$, and let $G\in {\cal G}_{\l}$.
For a vertex $u\in V(G)$ and a nonempty set $S\subseteq V(G)$, let $d(u,
S)=\min\{d(u, v):v\in S\}$, and let $L_i(S)=\{u\in V(G) \mbox{ and } d(u,
S)=i\}$ for any integer $i\ge 0$. We show that if $G[S]$ is connected and
$G[L_i(S)]$ is bipartite for each $i\in\{1, \ldots, \lfloor{\l\over
2}\rfloor\}$, then $G[L_i(S)]$ is bipartite for each $i>0$, and consequently
$\chi(G)\le 4$, where $G[S]$ denotes the subgraph induced by $S$. Let
$\theta^-$ be the graph obtained from the Petersen graph by deleting three
vertices which induce a path, let $\theta^+$ be the graph obtained from the
Petersen graph by deleting two adjacent vertices, and let $\theta$ be the graph
obtained from $\theta^+$ by removing an edge incident with two vertices of
degree 3. For a graph $G\in{\cal G}_2$, we show that if $G$ is 3-connected and
has no unstable 3-cutset then $G$ must induce either $\theta$ or $\theta^-$ but
does not induce $\theta^+$. As corollaries, $\chi(G)\le 3$ for every graph $G$
of ${\cal G}_2$ that induces neither $\theta$ nor $\theta^-$, and minimal
non-3-colorable graphs of ${\cal G}_2$ induce no $\theta^+$.
