Continuity mistake: When Jerry slips a photograph of Tom placing the chicken under Spike's arm in the cake, he inserts it with the printed side up. When Tom lifts up the cake, the photograph is now completely blank.
Continuity mistake: When we see a close up of the photo that Jerry has taken, look at the rug that Spike is lying on. You can see that it is completely different to the one when Jerry was taking a photo of Tom putting a chicken under Spike's arm earlier in the short.
Continuity mistake: When Joan is doing some sewing on her yellow dress, you can see that the ball of wool in the sewing basket next to her has nothing in it. But when Jerry puts one of the photographs inside the dress, two knitting needles have appeared. The needles then disappear in the next shot.
Continuity mistake: When Jerry hides one of the photographs inside the dress that Joan is making, you can see that the pair of scissors in Joan's sewing basket has a blue handle, but in the next shot it is now coloured red.
Continuity mistake: When Jerry shows Spike the photo of Tom being kicked out of the house, Spike is seen holding it with both hands, but when we the photo in the next shot, there is now only one hand on it.
Continuity mistake: When Tom is placing a chicken under Spike's arm, Jerry takes a photo and you can see a trail of fake paw marks. When Jerry emerges from the dark room with copies of the photo, he takes one copy from the pile and has a look at it, but the picture shows no paw marks at all.