In 1915, Hearst International Film Service was started to produce cartoons based on popular King Features comic strips. Among them were Krazy Kat, and like the Mutt and Jeff cartoons mentioned last week, the creators of the strips got all the credit!
Specifically mentioned in Leonard Maltin's book was "Krazy Kat and Ignatz Mouse - At The Circus," and here it is!
If you've ever read the original Krazy Kat comic strips, you can see how it didn't adapt very well to cartoons.
The Katzenjammer Kids were a more successful adaptation, as you can see from the cartoon below!
There were other King Features adaptations done at this time, but I haven't had any luck finding any of them to share here!