The small intestine, as mentioned in the description of other slides in this same set, is composed of the ileum, duodenum and jejunum. That being the case, why would the slide set containing the three identified parts of the dog small intestine also includes one labeled "dog small intestine"? Good question, but here is a better one:
Can you figure out, based on these pictures, which of the 3 sections this specimen came from?

This slide was purchased on Ebay and is part of 100 prepared slides " set B"