Conducted 3 experiments with a total of 62 male and 14 female Long-Evans rats to examine the adequacy of odor trails of rats receiving reinforcement as cues for discrimination learning in a T maze. After considerable training, Ss learned to select the arm entered by a previously reinforced S at better than chance levels when a paper floor was used and changed between each pair of Ss. A permanent wooden floor failed to produce any evidence of learning. If the number of Ss providing the odor trail was increased from 1-6, Ss showed improved discrimination performance after 105 trials on wooden floors. It is concluded that the odor trails of previously reinforced rats provide a weak cue, but one sufficient to influence discrimination performance. (21 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved)