Introduction.Let xt{t), Xt(0)=0, 0< (k = l, , n) be elements of n independent Wiener spaces.Let x(t) be an element of the product space of the n independent Wiener spaces.Throughout the paper we shall assume V(t, x) to be a Borel measurable function of t and the n-dimensional vector x=(xi, , xn) that is bounded in every finite Euclidean sphere of the (t, x) space, 0=< oo.These assumptions will not be restated in the rest of the paper.We shall often assume that V(t, x) satisfies additional regularity conditions specified later on in the paper. Let(1.1) y(t) = f V(r,x(r))dr. J oWe wish to relate the study of the Markov process(1.2) (x(t),y(t))to the study of certain differential and integral equations.Such a study is of interest for the following reasons.We obtain information about Markov processes of type (1.2).For certain choices of the function V(t, x), the study yields interesting information about the problem of the absorbing barrier in diffusion theory.Moreover, if we look at the problem from a different point of view, we obtain a general method of getting limit theorems of a certain type [2] (2).Consider the distribution function (1.3) a(a;t) = Pr {y(t) ^ a}.Let 5m=(G2), , G), where G?\ G?\ (k = l, , n) are independent, normally distributed random variables with mean 0 and variance 1.The distribution function of 1 z r(l, _+ m k/mt \m m112is the same as that of