It is shown that compressible cylindrical ends in compact foliated 3-manifolds spiral onto toral leaves.
Mathematics Subject Classifications (2000). 57R30, 57M99. In this paper M is a closed orientable three-dimensional manifold equipped with an orientable foliation F of dimension two. If the boundary NM of M is not empty, we always assume the components of NM are leaves of the foliation, and all foliations and maps considered are assumed to be at least of class C 2 .Understanding the asymptotic behavior of a leaf is a difficult problem in its full generality. Many authors have studied the limit set of ends in foliated manifolds and have tried to generalize Poincaré-Bendixson theorem (see for example [1,7]. Cantwell and Conlon have proven a theorem similar to Theorem 3 below for totally proper ends in a codimension one foliation [1] as well as for isolated planar ends of proper leaves with nonexponential growth (see Corollary 3.4 of [2]). More precisely they proved that totally proper leaves spiral on leaves at lower level (see Section 6 in [1]). Nishimori [6] has studied the asymptotic behavior of isolated ends whose limit set is a compact leaf. Hector [5] has classified foliations for which all leaves are cylinders, furnishing us with models where cylindrical ends appear.The aim of the present work is to generalize the main theorem of [3] by removing assumptions essential to its proof there. Moreover, the main assumptions of [1,2,7], namely that the leaves are either totally proper or of nonexponential growth, are replaced by a purely topological condition which makes the type of ends completely analogous to the type of orbits in dimension 2. More concretely, the main result of this work is the following (see Theorem 3 below): Every cylindrical and compressible end of a leaf L of F accumulates onto a toral leaf, provided that L = R 2 .