Electronic Journal of Differential Equations, Vol. 2001(2001), No. 32, pp. 1-19. Title: Cauchy problem for derivors in finite dimension Authors: Jean-Francois Couchouron (Univ. de Metz, France) Claude Dellacherie (Univ. de Rouen, France) Michel Grandcolas (Univ. de Metz, France) Abstract: In this paper we study the uniqueness of solutions to ordinary differential equations which fail to satisfy both accretivity condition and the uniqueness condition of Nagumo, Osgood and Kamke. The evolution systems considered here are governed by a continuous operators $A$ defined on $\mathbb{R}^N$ such that $A$ is a derivor; i.e., $-A$ is quasi-monotone with respect to $(\mathbb{R}^{+})^N$. Submitted December 4, 2000. Published May 8, 2001. Math Subject Classifications: 34A12, 34A40, 34A45, 34D05. Key Words: derivor; quasimonotone operator; accretive operator; Cauchy problem; uniqueness condition.