The Actress - S4-E22
Continuity mistake: Little Joe falls in love with Julia Grant, an aspiring actress who, with her son, is staying at the Ponderosa for several days. After she learns she has landed an acting job in San Francisco, she and her son leave the Ponderosa. As they ride off in their horse-drawn wagon, Joe is standing next to Ben and Hoss and he is waving goodbye with his right hand. In the following long shot, Joe has both hands on his hips and is staring at the ground.
Continuity mistake: In the Ponderosa home, Arturo Diaz, a Mexican freedom fighter, is shot by a renegade pistolero. Diaz falls on his back and Ben Cartwright rushes to his side. Diaz says "Adios" and then dies, with his head turned to the left. After a brief close-up of Ben, Diaz's head is now turned to the right.
Saga of Whizzer McGee - S4-E30
Continuity mistake: When Whizzer is pouring coins from a robbery into the hands of Melissa, she is wearing gloves in camera shots taken from one angle, but have bare hands in shots taken from another angle. This mistake is repeated 8 times.