It gained an even wider following with help from T-shirts, hats and other merchandise bearing a picture of Mr. Douglas’s pet dog, the aptly named Black Dog, for whom the restaurant was named.

The logo for his tavern on Martha’s Vineyard transformed a black Labrador-boxer mix into an international emblem for summertime. By Remy Tumin Robert Douglas, who built the Black Dog Tavern on ...

It gained an even wider following with help from T-shirts, hats, and other merchandise bearing a picture of Mr. Douglas’s pet dog, the aptly named Black Dog, for whom the restaurant was named.