An attractive woman from New York was driving through a remote part of Arizona when her car broke down. An American Indian on horseback came along and offered her a ride to a nearby town. 

She climbed up behind him on the horse and they rode off. The ride was uneventful, except that every few minutes the Indian would let out a "Ye-e-e-e-ha-a-a-a" so loud that it echoed from the surrounding hills.

When they arrived in town, he let her off at the local service station, yelled one final "Ye-e-e-e ha-a-a-a!" and rode off. 

"What did you do to get that Indian so excited?" asked the service-station attendant. 

"Nothing. I merely sat behind him on the horse, put my arms around his waist and held onto the saddle horn so I wouldn't fall off," the woman answered.

"Lady," the attendant said, "Indians don't use saddles."