A street urchin misunderstands, or pretends to misunderstand, the intentions of a woman talking to her dog and acts as if she were talking to him.
The full caption reads as follows:
Young lady. “Is it hungry, then? Come along, little darling, it shall have its dinner.”
Street-sweeper (overhearing and misapplying). “Here y’ are miss! Right you are! I jest am!
[Ah, but it was Fido she was speaking to!]