  We describe automorphisms and derivations of the incidence coalgebra
$\text{Co}(X,F)$ of the partially ordered set $X$ over a field $F$. In this
case, the fact is significantly used that the dual algebra of the coalgebra
$\text{Co}(X,F)$ is isomorphic to the incidence algebra $I(X,F)$ of the
partially ordered set $X$ over the field $F$.
