Dorothy and the Scarecrow in Oz is a lost adaptation of Dorothy and the Wizard in Oz made by the Selig Polyscope Company which also had elements from The Wonderful Wizard of Oz. The film might have been about 15 minutes long as the reel length was listed at 1,000 feet.
From a description in Views and Film Index, it was released on April 14th, 1910 with its plot being:
Dorothy and the Scarecrow are now in the Emerald City. They have become friendly with the Wizard, and together with the Woodman, the Cowardly Lion, and several new creations equally delightful, they journey through Oz -- the earthquake -- and into the glass city. The Scarecrow is elated to think he is going to get his brains at last and be like other men are; the Tin-Woodman is bent upon getting a heart, and the cowardly lion pleads with the great Oz for courage. All these are granted by his Highness. Dorothy picks the princess. -- The Dangerous Mangaboos. -- Into the black pit, and out again. We then see Jim, the cab horse, and myriads of pleasant surprises that hold and fascinate.
It is known from IMDb that Marcia Moore played Dorothy in this adaptation along with The Land of Oz (1910). The rest of the cast is unknown as at least 10 people appear in the only image.