This paper investigates
the behavior of limit cycles of a planar dynamical system which has been
perturbed transversally. In particular, it is shown that if C is a limit cycle
of the unperturbed dynamical system, then there are limit cycles of the
perturbed dynamical systems arbitrarily close to C. Also, if C is an exterior
Iimit cycle of the unperturbed dynamical system, then there is an outer
neighborhood of C which consists solely of cycles of the perlurbed dynamical
systems.