Continuity mistake: When Pinocchio is locked up in the cage of Stromboli, Jiminy goes inside the cage lock, and he hangs his coat and hat on the outside of the lock. In the next shot, they have disappeared.
Other mistake: In the intro to the Pastoral Symphony, the narrator identifies the deity who cloaks the world with Night to be Morpheus, who is the Greek god of sleep and dreams. However, the character in the animation is fairly obviously female, with long hair, eye shadow, and lipstick. My theory is that the character was intended by the art team to be Nyx, the Greek goddess of Night. Night would be a more likely candidate to be making it nighttime across the world, while Morpheus would be more likely to put people to sleep or send them dreams.
Suggested correction: Without further evidence/proof, this theory remains just that. A theory.
Continuity mistake: Once Spunky is kidnapped and Hunky takes off chasing the truck, you see the truck going along the road passing just some grass and one large rock on its left side. Once Hunky catches up to the truck, it cuts to a side view close up of him and Spunky's head sticking out the back, and suddenly the truck is passing a very large rock that was not there in the previous shot. The rock is taller than the truck, so it would have shown. And then it's very obvious the background is then looped as the same huge rock passes the truck every few seconds repeatedly. (00:01:35)
Continuity mistake: When Porky is searching for his contract in the waste-paper basket in Leon Schlesinger's office, he leaves some paper on the floor. But when Leon tells him to go back to work, we cut to Porky and the paper has gone.
Continuity mistake: After Mickey hides Pluto in his suitcase in Burbank, Mickey picks up his cane and runs to the train, then when Mickey actually jumps onto the train caboose he's only carrying his suitcase, he does not have his cane, nor does he have Pluto's suitcase (which had been filled with bones) with him. The cane reappears on the train later, and at the end Pluto's suitcase mysteriously reappears when Pete throws it at the duo in Pomona.
Continuity mistake: When Elmer thinks he's going mad, we see a close-up of the book "How to Photograph Wild Life" and you can see there is damage to the front cover and the spine. But when the rabbit throws the book at Elmer at the end of the cartoon, there is now no damage to the book at all.
Continuity mistake: When Elmer thinks he has captured Bugs in his trap, there is a sign by the trap that reads "Carrots." In the next shot, the sign has gone.
Continuity mistake: After the mouse is revived by water from Jasper, he goes up to the cat and you can see that the mouse's left hand is under Jasper's mouth, but in the next shot his hand is now near the whisker area.
Continuity mistake: When Papa Bear is drinking from the hot water tap after eating the hot porridge, the tap handle changes position between shots.
Continuity mistake: At the beginning of the cartoon, you can see the front of Donald Duck's kayak has nothing on it. But after he is soaked by a waterfall, a lever appears out of nowhere. The lever disappears in the next shot, but when he arrives at the campsite, it is back again.