The quartic differential systems with a non-degenerate monodromic critical point and non-degenerate infinity are considered. We showthat in this family the maximal multiplicity of the line at infinity is seven. Modulo the affine transformation and time rescaling the classes of systems with the line of infinity of multiplicity two, three, . . . , seven are determined. In the cases when the quartic systems have the line at infinity of maximal multiplicity the problem of the center is solved.

ˆIn aceast˘a lucrare sunt examinate sistemele diferent¸iale cuartice cu un punct critic monodromic nedegenerat s¸i infinitul nedegenerat. Se arat˘a c˘a ˆın aceast˘a familie de sisteme multiplicitatea maximal˘a a dreptei de la infinit este egal˘a cu s¸apte. Cu exactitatea unei transform˘ari afine de coordonate s¸i rescalarea timpului sunt determinate clasele de sisteme cu dreapta de la infinit de multiplicitatea doi, trei, . . . , s¸apte. ˆIn cazurile cˆand sistemele cuartice au linia de la infinit de multiplicitate maximal˘a problema centrului este rezolvat˘a.