  An algebra $\mathbf A = \langle A, \to, 0 \rangle$, where $\to$ is binary and
$0$ is a constant, is called an implication zroupoid ($\mathcal I$-zroupoid,
for short) if $\mathbf A$ satisfies the identities: (I): $(x \to y) \to z
\approx ((z' \to x) \to (y \to z)')'$, and (I$_{0}$): $ 0'' \approx 0$, where
$x' : = x \to 0$. An implication zroupoid is symmetric if it satisfies the
identities: $x'' \approx x$ and $(x \to y')' \approx (y \to x')'$. An identity
is of Bol-Moufang type if it contains only one binary operation symbol, one of
its three variables occurs twice on each side, each of the other two variables
occurs once on each side, and the variables occur in the same (alphabetical)
order on both sides of the identity. In this paper we make a systematic
analysis of all $ 60$ identities of Bol-Moufang type in the variety $\mathcal
S$ of symmetric $\mathcal I$-zroupoids. We show that $47$ of the subvarieties
of $\mathcal S$, defined by the identities of Bol-Moufang type are equal to the
variety $\mathcal{SL}$ of $\lor$-semilattices with the least element $0$ and,
one of the others is equal to $\mathcal S$. Of the remaining 12, there are only
$3$ distinct ones. We also give an explicit description of the poset of the
(distinct) subvarieties of $\mathcal S$ of Bol-Moufang type.
